Superfluidity of a perfect quantum crystal

In recent years, experimental data were published which point to the possibility of the existence of superfluidity in solid helium. To investigate this phenomenon theoretically we employ a hierarchy of equations for reduced density matrices which describes a quantum system that is in thermodynamic equilibrium below the Bose-Einstein condensation point, the hierarchy being obtained earlier by the author. It is shown that the hierarchy admits solutions relevant to a perfect crystal (immobile) in which there is a frictionless flow of atoms, which testifies to the possibility of superfluidity in ideal solids. The solutions are studied with the help of the bifurcation method and some their peculiarities are found out. Various physical aspects of the problem, among them experimental ones, are discussed as well.Comment: 24 pages with 2 figures, version accepted for publication in Eur.Phys.J.

Half-life of the electron-capture decay of 97Ru: Precision measurement shows no temperature dependence

We have measured the half-life of the electron-capture (ec) decay of 97Ru in a metallic environment, both at low temperature (19K), and also at room temperature. We find the half-lives at both temperatures to be the same within 0.1%. This demonstrates that a recent claim that the ec decay half-life for 7Be changes by $0.9% +/- 0.2% under similar circumstances certainly cannot be generalized to other ec decays. Our results for the half-life of 97Ru, 2.8370(14)d at room temperature and 2.8382(14)d at 19K, are consistent with, but much more precise than, previous room-temperature measurements. In addition, we have also measured the half-lives of the beta-emitters 103Ru and 105Rh at both temperatures, and found them also to be unchanged.Comment: 6 pages, 6 figure

Universal mechanism of discontinuity of commensurate-incommensurate transitions in three-dimensional solids: Strain dependence of soliton self-energy

We show that there exists a universal mechanism of long-range soliton attraction in three-dimensional solids and, therefore, of discontinuity of any commensurate-incommensurate (C-IC) phase transition. This mechanism is due to the strain dependence of the soliton self-energy and specific features of the solid-state elasticity. The role of this mechanism is studied in detail for a class of C-IC transitions where the IC modulation is one-dimensional, the anisotropy in the order parameter space is small, and the symmetry of the systems allows the existence of the Lifshitz invariant. Two other mechanisms of soliton attraction are operative here but the universal mechanism considered in this paper is found to be the most important one in some cases. Comparison with the most extensively studied C-IC transition in $\rm K_2SeO_4$ shows that the experimentally observed thermal anomalies can be understood as a result of the smearing of the theoretically predicted discontinuous transition.Comment: 8 pages (extended version, title changed

The Minimal Length of a Lagrangian Cobordism between Legendrians

To investigate the rigidity and flexibility of Lagrangian cobordisms between Legendrian submanifolds, we investigate the minimal length of such a cobordism, which is a $1$-dimensional measurement of the non-cylindrical portion of the cobordism. Our primary tool is a set of real-valued capacities for a Legendrian submanifold, which are derived from a filtered version of Legendrian Contact Homology. Relationships between capacities of Legendrians at the ends of a Lagrangian cobordism yield lower bounds on the length of the cobordism. We apply the capacities to Lagrangian cobordisms realizing vertical dilations (which may be arbitrarily short) and contractions (whose lengths are bounded below). We also study the interaction between length and the linking of multiple cobordisms as well as the lengths of cobordisms derived from non-trivial loops of Legendrian isotopies.Comment: 33 pages, 9 figures. v2: Minor corrections in response to referee comments. More general statement in Proposition 3.3 and some reorganization at the end of Section

A case report of late local relapse of adrenocortical carcinoma 18 years after adrenalectomy

Adrenocortical cancer is an extremely rare tumor presenting with extensive locoregional spread at the time of diagnosis. Due to the diagnostic difficulties preoperatively and a lack of effective treatment options, patients have poor prognosis. Patients succumb to metastases within a couple of months. Only 20 cases have been so far reported in the literature with a medium disease-free survival up to 2 years. We present a case of a locoregional recurrence of adrenocortical cancer 18 years after left adrenalectomy. Key Words: аdrenocortical carcinoma, local relapse, adrenalectomy, long-term survival, nephrectomy

Second harmonic generation on incommensurate structures: The case of multiferroic MnWO4

A comprehensive analysis of optical second harmonic generation (SHG) on an incommensurate (IC) magnetically ordered state is presented using multiferroic MnWO4 as model compound. Two fundamentally different SHG contributions coupling to the primary IC magnetic order or to secondary commensurate projections of the IC state, respectively, are distinguished. Whereas the latter can be described within the formalism of the 122 commensurate magnetic point groups the former involves a breakdown of the conventional macroscopic symmetry analysis because of its sensitivity to the lower symmetry of the local environment in a crystal lattice. Our analysis thus foreshadows the fusion of the hitherto disjunct fields of nonlinear optics and IC order in condensed-matter systems

Хірургічне лікування вторинного гіперпаратиреозу у пацієнтів з хронічною хворобою нирок

Мета. Дослідити ефективність оперативного лікування вторинного гіперпаратиреозу (ВГПТ) у пацієнтів з хронічною хворобою нирок (ХХН). Матеріали і методи. Проведено ретроспективне дослідження результатів оперативних втручань на прищитоподібних залозах (ПЩЗ) та оцінено клініко-лабораторні показники у пацієнтів з ВГПТ. Результати. Шляхом дослідження операційного матеріалу ПЩЗ 62 пацієнтів дифузну гіперплазію встановлено у 8 (12,9%, 95% довірчого інтервалу (ДІ), 4,6 - 21,2%), мікроаденоматоз – у 14 (22,6%, 95% ДІ 12,2 – 33,0%); макроаденому – у 40 (64,5%, 95% ДІ 52,6 - 76,4%). Із 40 пацієнтів з макроаденомами пухлини з головних клітин діагностовано у 32 (80%, 95% ДІ 67,9 – 92,4%), онкоцитарні пухлини – у 8 (20%, 95% ДІ 7,6 – 32,4%). Відношення шансів (OR) – 16,0; χ2 – 26,45; р < 0,0001. Порівняння клініко-лабораторних показників через 1, 6 і 12 міс після оперативного втручання на ПЩЗ, а також з показниками у пацієнтів, яким не виконували оперативного втручання, виявило статистично достовірні результати нормалізації рівнів паратиреоїдного гормону (ПТГ), кальцію (Са), фосфору (Р) і лужної фосфатази (ЛФ) у крові. Висновки. Хірургічна операція при ВГПТ є ефективним методом лікування, який сприяє нормалізації лабораторних показників і попереджає важкі ускладнення

Intercomparison of field measurements of nitrous acid (HONO) during the SHARP campaign

Because of the importance of HONO as a radical reservoir, consistent and accurate measurements of its concentration are needed. As part of SHARP (Study of Houston Atmospheric Radical Precursors), time series of HONO were obtained by six different measurement techniques on the roof of the Moody Tower at the University of Houston. Techniques used were long path differential optical absorption spectroscopy (DOAS), stripping coil-visible absorption photometry (SC-AP), long path absorption photometry (LOPAP® ), mist chamber/ion chromatography (MC-IC), quantum cascade-tunable infrared laser differential absorption spectroscopy (QC-TILDAS), and ion drift-chemical ionization mass spectrometry (ID-CIMS). Various combinations of techniques were in operation from 15 April through 31 May 2009. All instruments recorded a similar diurnal pattern of HONO concentrations with higher median and mean values during the night than during the day. Highest values were observed in the final 2 weeks of the campaign. Inlets for the MC-IC, SC-AP, and QC-TILDAS were collocated and agreed most closely with each other based on several measures. Largest differences between pairs of measurements were evident during the day for concentrations ~100 parts per trillion (ppt). Above ~ 200 ppt, concentrations from the SC-AP, MC-IC, and QC-TILDAS converged to within about 20%, with slightly larger discrepancies when DOAS was considered. During the first 2 weeks, HONO measured by ID-CIMS agreed with these techniques, but ID-CIMS reported higher values during the afternoon and evening of the final 4 weeks, possibly from interference from unknown sources. A number of factors, including building related sources, likely affected measured concentrations

Quality of life in patients after cystectomy as the main aim while making a choice for the urine derivation procedure

Objective. To estimate a quality of life (QL) in the patients after radical cystectomy, depending upon the urine derivation method. Materials and methods. Clinical analysis and estimation of QL was conducted in 76 patients, to whom radical cystectomy was performed (the main group). For the urine derivation after radical cystectomy the orthotopic reconstruction of the bladder in accordance to Schtruder’s procedure was accomplished in 26 (34.2%) patients, while Brikker’s ileoplasty – in 50 (65.8%) patients. With the aim for objectivization and standardization of the QL estimation procedure after reconstructive operative intervention on the lower urinary ways in 1 and 12 mo a social-clinical method of the investigation, basing on questionnaire «Medical Outcomes Study – Short Form» (SF-36), was applied. Sexual function was estimated, using questionnaire IIEF-5 (International Index of Erectile Function). Results. Socio-clinical investigations of QL have revealed the best indices in 12 mo in the patients, to whom orthotopic reconstruction of the bladder in accordance to Schtuder’s procedure was done, what differs from the Brikker’s ileoplasty procedure, concerning social functioning, psychological health and vital activity on 18.1, 12.5 and 25% accordingly. All the QL indices in the groups investigated have improved in 12 mo postoperatively, what witnesses about progressing social rehabilitation, not depending upon the kind of the urine derivation. The method of the urine derivation do not influences erectile function, and the main significance is gaining the preservation of nervous and vascular elements of a small pelvis. Conclusion. The results obtained witnesses, that in a psychological way the patients, having a newcyst and with a continent derivation of the urine are accepting their state as a more physiological one. This makes possible the conduction of maximal socio-clinical rehabilitation and adaptation of the able-bodied contingent of patients