Rendu-Osler-Weber Disease with High Pulmonary Hypertension and Interstitial Lung Disease

A 64-year-old female with a family history of hereditary hemorrhagic telangiectasia (HHT) was hospitalized due to complaints of dyspnea during light physical exertion and leg edema. HHT was diagnosed at 20 y.o., recurrent nasal bleeding started at age 52, bleedings severity was aggravated by not completely compensated hypertension. At the age of 60, after a massive hemorrhage, she noted the onset of dyspnea, edema, ascites. Diuretics and iron preparations improved her well-being, but from that period onward her heart failure worsened after each massive blood loss. The last major bleeding was before the present hospitalization (Hgb 67 g/l), after which heart failure symptoms significantly deteriorated. Echocardiography showed preserved left ventricular ejection fraction, but revealed high pulmonary hypertension (systolic pulmonary artery pressure 69 mmHg). Chest computed tomography (CT) with contrast showed no evidence of pulmonary embolism, but interstitial lung lesions were detected. Pulse therapy with glucocorticosteroids did not result in positive dynamics at the control CT scan, which allowed to reject a separate interstitial lung disease. As a result of cardiotropic and diuretic therapy, as well as correction of anemia, the patient's condition improved. Macitentan was administered, but the patient refused from it because one of possible side effects was anemia. A year later the patient diedfrom acute progression of pulmonary hypertension. According to the literature, pulmonary hypertension in HHT can have a significant impact on the prognosis and requires timely diagnosis and treatment. Interstitial lung lesions are a manifestation of the underlying disease and does not require special treatment

Evaporation induced flow inside circular wells

Flow field and height averaged radial velocity inside a droplet evaporating in an open circular well were calculated for different modes of liquid evaporation.Comment: 5 page, 3 figures, submitted to European Physical Journal

Magnetic properties of the antiferromagnetic spin-1/2 chain system β\beta-TeVO4_{4}

The magnetic susceptibility and magnetization of high quality single crystal beta-TeVO4 are reported. We show that this compound, made of weakly coupled infinite chains of VO5 pyramids sharing corners, behaves as a S = 1/2 one-dimensional Heisenberg antiferromagnet. From magnetic experiments we deduce the intrachain antiferromagnetic coupling constant J/kB = 21.4 $\pm$ 0.2 K. Below 5 K a series of three phase transitions at 2.26, 3.28 and 4.65 K is observed.Comment: Accepted for publication in Physical Review

Russian Higher School: Forced Distance Learning and Planned Switch to Distance Learning During Pandemic (Experience of Sociological Analysis)

Challenges related to the COVID-19 pandemic require structural analysis and sociocultural comprehension, which has and will for quite a while have multi-aspect and systemic nature. All elements of the social system have been forced to function in the stress regime in the absence of any basic patterns and tried-and-true methods to solve the arising problem. The overall uncertainty in the organization of the social life and the enforced and, at times, very contentious steps taken at various levels of management have caused polarization of opinions as to the functioning of all social institutions. Special pressure has been put on education, since it is this  institution that is mainly responsible for the social system’s stability. In this regard, it has been important and significant to comprehensively  study the problems and limitations associated with the functioning of the  higher education system in Russia during the pandemic, as well as to analyze the change in tone and attitude both on the part of the public and the teaching corps, as a response to the transition to the new forms of work at higher education institutions.The article was prepared using the materials of two stages of the  sociological research “The opinion of teachers of Russia’s higher education  institutions on distance learning during the pandemic” conducted in May, June and December 2020. The volume of sample sets made up 3431 people at the first stage, and 6006, at the second. An analysis of research data covers the following areas: organizational problems of transition to distance  learning; resources used, organization of lectures and seminars, assessment  of the positive and negative aspects of distance learning; perspectives,  limitations and trajectories for the implementation of distance learning in Russia’s higher education institutions, as well as a set of social problems aimed at studying social well-being and assessing possible changes in the life and career of teachers.The research data are compared with the data of similar works by Russian and foreign analysts. On the basis of the analysis done and the conclusions obtained, the authors propose practical steps to optimize the work of the higher education system in stressful situations, to use distance technologies in the learning organization. Also, possible forms are considered that  combine distance and full-time education, and recommendations are proposed on how to change the tone in perceiving inevitable informational and communication transformations on the part of teachers.This research was performed according to the Development program of the  Interdisciplinary Scientific and Educational School of Lomonosov Moscow  State University «Mathematical methods of complex systems analysis»

The temperature and chronology of heavy-element synthesis in low-mass stars

Roughly half of the heavy elements (atomic mass greater than that of iron) are believed to be synthesized in the late evolutionary stages of stars with masses between 0.8 and 8 solar masses. Deep inside the star, nuclei (mainly iron) capture neutrons and progressively build up (through the slow-neutron-capture process, or s-process) heavier elements that are subsequently brought to the stellar surface by convection. Two neutron sources, activated at distinct temperatures, have been proposed: 13C and 22Ne, each releasing one neutron per alpha-particle (4He) captured. To explain the measured stellar abundances, stellar evolution models invoking the 13C neutron source (which operates at temperatures of about one hundred million kelvin) are favoured. Isotopic ratios in primitive meteorites, however, reflecting nucleosynthesis in the previous generations of stars that contributed material to the Solar System, point to higher temperatures (more than three hundred million kelvin), requiring at least a late activation of 22Ne. Here we report a determination of the s-process temperature directly in evolved low-mass giant stars, using zirconium and niobium abundances, independently of stellar evolution models. The derived temperature supports 13C as the s-process neutron source. The radioactive pair 93Zr-93Nb used to estimate the s-process temperature also provides, together with the pair 99Tc-99Ru, chronometric information on the time elapsed since the start of the s-process, which we determine to be one million to three million years.Comment: 30 pages, 10 figure

Peculiarities of the Formation of Educational Trajectories of Russian Students: Assessment and Opportunities

New geopolitical challenges that necessitate the formation of a nationally oriented education system require a multidimensional analysis, socio-cultural understanding and the search for new formats for the organization of higher education in Russia. In the conditions of the post-Bologna reality, Russia needs to create its own model of higher education, which will be able to provide the economy with highly qualified personnel, which will coopt all the best from the classical Soviet system of education and will be able to build on the national traditions, interests of students, their parents, teachers and employers. In this regard, it is relevant to analyze and evaluate the requests of nowadays students for these changes and the nature of those changes.The article is based on the materials of the authors’ sociological research (N=123977 people), conducted in 2022.The problematic area of the research supposed that the revision of the existing predominantly two-level (bachelor and master) structure of higher education requires a transition to the optimal and traditional for Russia model of the specialist program with the introduction of more flexible forms of work, the possibility of changing the educational trajectory in the learning process, the search for new ways of academic mobility and universities cooperation.The research data are compared with the data of similar works of Russian and foreign analysts. An analysis of the opinion of Russian students showed that in the process of learning and gradually entering a specialty, some students need certain changes in the chosen training program made upon admission. The possibility or impossibility of implementing these changes determines their motivation for learning, academic achievements, further educational and professional trajectories, and satisfaction with education in general. Based on the analysis done and the results obtained, the authors propose practical steps to form a new structure of higher education based on the specialist program. They suggest recommendations on the necessary changes in the legislative, organizational, educational and methodological nature related to this process

Surprises in the Orbital Magnetic Moment and g-Factor of the Dynamic Jahn-Teller Ion C_{60}^-

We calculate the magnetic susceptibility and g-factor of the isolated C_{60}^- ion at zero temperature, with a proper treatment of the dynamical Jahn-Teller effect, and of the associated orbital angular momentum, Ham-reduced gyromagnetic ratio, and molecular spin-orbit coupling. A number of surprises emerge. First, the predicted molecular spin-orbit splitting is two orders of magnitude smaller than in the bare carbon atom, due to the large radius of curvature of the molecule. Second, this reduced spin-orbit splitting is comparable to Zeeman energies, for instance, in X-band EPR at 3.39KGauss, and a field dependence of the g-factor is predicted. Third, the orbital gyromagnetic factor is strongly reduced by vibron coupling, and so therefore are the effective weak-field g-factors of all low-lying states. In particular, the ground-state doublet of C_{60}^- is predicted to show a negative g-factor of \sim -0.1.Comment: 19 pages RevTex, 2 postscript figures include

Dynamical Jahn-Teller Effect and Berry Phase in Positively Charged Fullerene I. Basic Considerations

We study the Jahn-Teller effect of positive fullerene ions $^2$C$_{60}^{+}$ and $^1$C$_{60}^{2+}$. The aim is to discover if this case, in analogy with the negative ion, possesses a Berry phase or not, and what are the consequences on dynamical Jahn-Teller quantization. Working in the linear and spherical approximation, we find no Berry phase in $^1$C$_{60}^{2+}$, and presence/absence of Berry phase for coupling of one $L=2$ hole to an $L=4$/$L=2$ vibration. We study in particular the special equal-coupling case ($g_2=g_4$), which is reduced to the motion of a particle on a 5-dimensional sphere. In the icosahedral molecule, the final outcome assesses the presence/absence of a Berry phase of $\pi$ for the $h_u$ hole coupled to $G_g$/$H_h$ vibrations. Some qualitative consequences on ground-state symmetry, low-lying excitations, and electron emission from C$_{60}$ are spelled out.Comment: 31 pages (RevTeX), 3 Postscript figures (uuencoded

Infective and nonbacterial thrombotic endocarditis in patients with post-COVID-19 viral-immune myocarditis

The possibility of heart inflammation (both myocardial and endocardial) months after a coronavirus disease 2019 (COVID-19) has not been practically studied, especially since approaches to the treatment of myocarditis in combination with various endocarditis forms have not been developed.Aim. To study the prevalence and mechanisms of SARS-CoV-2-associated endocardial injury in patients with morphologically verified post-COVID-19 myocarditis, as well as to develop approaches to comprehensive therapy.Material and methods. The study included 18 patients with severe morphologically verified post-COVID-19 myocarditis (men, 9; 51,1±9,4 years; 35 to 66 years). Patients with prior verified myocarditis/myocardial infarction, rheumatic heart disease, and systemic immune diseases were excluded. The average time after COVID-19 was 6,5 [3.5; 10] months The diagnosis of myocarditis was confirmed by endomyocardial biopsy (including immunohistochemical examination with antibodies to CD3, CD20, CD45, CD68, and to SARS-CoV-2 antigens; polymerase chain reaction for SARS-CoV-2 RNA, DNA of cardiotropic viruses). The blood level of anticardiac antibodies was determined by indirect immunofluorescence. In addition, echocardiography, magnetic resonance imaging (n=8), cardiac multislice tomography (n=1), and coronary angiography (n=14) were performed.Results. Biopsy revealed active (n=12) and borderline (n=3) lymphocytic myocarditis, eosinophilic (n=2) and giant cell (n=1) myocarditis. In 4 patients, nonbacterial thrombotic endocarditis (NBTE) with parietal and intravascular thrombosis was diagnosed, and in one patient — infective endocarditis (IE) of the bicuspid aortic valve. Myocardial persistence of SARS-CoV-2 was detected in 72% of cases (in 3 patients — with NBTE; in 1 — with IE; in 9 — without endocarditis). Titers of anticardiac antibodies increased by 3-4 times in 94% of patients. Patients with endocarditis were characterized by larger heart chambers, lower ejection fraction (27,5±6,6 vs 36,0±13,4%), more severe pulmonary hypertension, and valvular regurgitation. Intraventricular thrombosis according to echocardiography/magnetic resonance imaging and cardiac embolism was not observed. Treatment in all patients included methylprednisolone at an average dose of 24 mg a day. In 10 patients, the result was monitored for at least 3 months as follows: the ejection fraction was 46,0±12,7% and 44,3±7,3% in patients with and without endocarditis, respectively.Conclusion. Endocarditis in patients with post-COVID-19 myocarditis was detected in 28% (1 patient — IE; 4 — NBTE). The key mechanisms of post-COVID-19 myocarditis and NBTE are long-term (up to 18 months) myocardial persistence of SARS-Cov-2 and the development of an autoimmune reaction. Endocarditis was diagnosed in more severe patients, including those with giant cell and eosinophilic myocarditis. The effectiveness of steroid therapy in combination with anticoagulants in patients with NBTE requires further study. In case of IE, steroids can also be used in the treatment of myocarditis (in combination with antibiotics and immunoglobulin)

Search for New Physics with Jets and Missing Transverse Momentum in pp collisions at sqrt(s) = 7 TeV

A search for new physics is presented based on an event signature of at least three jets accompanied by large missing transverse momentum, using a data sample corresponding to an integrated luminosity of 36 inverse picobarns collected in proton--proton collisions at sqrt(s)=7 TeV with the CMS detector at the LHC. No excess of events is observed above the expected standard model backgrounds, which are all estimated from the data. Exclusion limits are presented for the constrained minimal supersymmetric extension of the standard model. Cross section limits are also presented using simplified models with new particles decaying to an undetected particle and one or two jets