Resonant optical electron transfer in one-dimensional multiwell structures

We consider coherent single-electron dynamics in the one-dimensional nanostructure under resonant electromagnetic pulse. The structure is composed of two deep quantum wells positioned at the edges of structure and separated by a sequence of shallow internal wells. We show that complete electron transfer between the states localized in the edge wells through one of excited delocalized states can take place at discrete set of times provided that the pulse frequency matches one of resonant transition frequencies. The transfer time varies from several tens to several hundreds of picoseconds and depends on the structure and pulse parameters. The results obtained in this paper can be applied to the developments of the quantum networks used in quantum communications and/or quantum information processing.Comment: 25 pages,16 figure

Single-qubit operations in the double-donor structure driven by optical and voltage pulses

We study theoretically the quantum dynamics of an electron in the singlyionized double-donor structure in the semiconductor host under the influence of laser pulses whose frequencies are close to structure resonant frequencies. This system can be used as a charge qubit where the logical states are defined by the lowest two energy states of the remaining valence electron localized around one or another donor. The quantum operations are performed via resonant or Raman-like transitions between the localized (qubit) states and the excited states delocalized over the structure, combined with phase shifts between qubit states generated by voltage pulses. The possibility of realization of arbitrary single-qubit rotations is demonstrated.Comment: to appear in Phys. Rev.

Physical education for young students. Typologies, gaps, challenges

In the current 21st century situation, some services priorities have changed significantly, but there are always unshakable pillars. One of these pillars is physical culture. The impact of physical education and sport in General on human health, its development (both physical and spiritual) is difficult to overestimate. No wonder there are such sayings as: "In healthy body – healthy spirit" and "Sport is life. In his article, we turn to consider the approaches to organization of physical education in schools, and also to track the challenges the modern University sport facesВ сложившейся в 21-ом веке ситуации, некоторые общественные приоритеты существенно изменились, но всегда есть незыблемые столпы. Одним из таких столпов является физическая культура. Влияние физкультуры и спорта в целом на здоровье человека, на его развитие (как физическое, так и духовное) сложно переоценить. Не зря ведь существуют такие пословицы как: «В здоровом теле – здоровый дух» и «Спорт – это жизнь. В своей статье мы беремся рассмотреть подходы к организации физического воспитания в учебных заведениях, а также проследить те вызовы, с которыми современный студенческий спорт сталкиваетс

Auxiliary-level-assisted operations with charge qubits in semiconductors

We present a new scheme for rotations of a charge qubit associated with a singly ionized pair of donor atoms in a semiconductor host. The logical states of such a qubit proposed recently by Hollenberg et al. are defined by the lowest two energy states of the remaining valence electron localized around one or another donor. We show that an electron located initially at one donor site can be transferred to another donor site via an auxiliary molecular level formed upon the hybridization of the excited states of two donors. The electron transfer is driven by a single resonant microwave pulse in the case that the energies of the lowest donor states coincide or two resonant pulses in the case that they differ from each other. Depending on the pulse parameters, various one-qubit operations, including the phase gate, the NOT gate, and the Hadamard gate, can be realized in short times. Decoherence of an electron due to the interaction with acoustic phonons is analyzed and shown to be weak enough for coherent qubit manipulation being possible, at least in the proof-of-principle experiments on one-qubit devices.Comment: Extended version of cond-mat/0411605 with detailed discussion of phonon-induced decoherence including dephasing and relaxation; to be published in JET

Extracorporeal ultrasound exposure by the low-frequency acoustic amplitude-modulated signal on a ureteral stent for preventing its incrustation: experimental determination of optimal application points

Introduction. Incrustation and biofilms formation on the surface of ureteral stents are still the most significant complications of internal drainage of the upper urinary tract. There are much researchers conducted to combat these complications. The lack of a solution to this problem affects the ultimate results of treatment and economic losses. The issue of impact by physical methods on the ureteral stent, particularly the use of extracorporeal ultrasound acoustic exposure remains, promising and poorly covered.Purpose of the study. To determine the optimal application points of extracorporeal acoustic exposure by the low-frequency ultrasonic amplitude-modulated signal on a ureteral stent in an experiment.Materials and methods. The original device was designed. The main principle of its operation is the generation of an amplitude-modulated ultrasonic signal in two modes: pulsed and permanent. A sexually mature mongrel dog was an experimental animal. The ureteral stent was placed by laparotomy and cystotomy. Intraoperatively, the emitter of the developed device was applied to the skin of the animal, according to the previously indicated topographic and anatomical landmarks. At the same time, an ultrasonic wave noise analyzer was applied through the laparotomy wound to the appropriate level of the ureter. Measurements of ultrasound intensity indicators were performed three times in two operating modes of the device.Results. Pulsed mode: for the ureteral upper third, the highest ultrasonic intensity (123.67 dB) was achieved along the posterior axillary line. For the ureteral middle third, the best ultrasound intensity (115 dB) was obtained by the posterior axillary line. For the ureteral lower third, the highest ultrasound intensity (113.67 dB) was noted along the middle axillary line.Permanent mode: the best ultrasonic intensity in the projection of the ureteral upper, middle, and lower thirds was achieved along the posterior axillary line and was 118.67 dB, 117 dB and 116.67 dB, accordingly. However, there was an excessive heat effect, manifested by hyperemia and hyperthermia of the animal's skin, fascicular muscle contractions during the instrument functioned in the permanent mode, which can potentially lead to thermal burns and intolerance to the procedure.Conclusion. The pulsed mode of the device function is most safe. The optimal application points of the instrument emitter for the ureteral upper and middle thirds is the posterior axillary line, and for the ureteral lower third is the middle axillary line

Anthropometric characteristics of patients suffering from chronic cystitis

Introduction. With a depressingly high prevalence of chronic cystitis (it is believed that half of women suffer from acute cystitis at least once in their lives), there is still no clarity on this disease. We were unable to find any studies on the anthropometric characteristics of patients with chronic cystitis either in the domestic or in the English literature.Objective. To assess the anthropometric characteristics of patients with chronic recurrent cystitis.Material & methods. A prospective multicenter cohort study included 91 patients with symptoms of acute cystitis. All underwent anthropometric measurements, analyzed complaints, studied anamnesis morbi et vitae, performed a study on a gynecological chair; urine was sent for general analysis and bacteriological examination for nonspecific microflora with the determination of the sensitivity of the isolated pathogen to antimicrobial drugs. The patients answered questions about the Russian version of the Acute Cystitis Symptom Score (ACSS). A urethra and cervical canal smear was studied using the polymerase chain reaction method to identify the causative agents of sexually transmitted infections. The diagnosis was considered confirmed in the presence of leukocyturia, bacteriuria, and the sum of symptoms on the ACSS scale was 6 or more.Results. The duration of chronic recurrent cystitis was averaged at 7.1 ± 4.2 years. The age of the patients ranged from 18 to 49 years, averaging 28.9 ± 3.9 years. The height ranged from 150 cm to 178 cm, on average 165.9 ± 7.1 cm. The average weight was within the normal range: 64.2 ± 6.1 kg. However, the spread in the cohort by body weight was two-fold: from 42 to 86 kg. Overweight was found in five (5.5%) patients; two patients (2.2%), on the contrary, had a body weight deficit. When analyzing anthropometric indicators, along with the obvious ones (direct dependence of the duration of the disease on the age of the patient; direct dependence of the quality of life on the severity of symptoms), other statistically significant correlations were established: a positive relationship between age and weight, weight and duration of the disease.Conclusion. The analysis showed that overweight women respond to treatment worse, they have a longer history of cystitis. Neither typical symptoms nor ACSS score correlated with any of the anthropometric measures

Large Rearrangements in Genes Responsible for Familial Adenomatous Polyposis, <i>MUTYH</i>-Associated Polyposis and Peutz–Jeghers Syndrome in Russian Patients

Аim: to reveal the rate of large rearrangements in the genes responsible for familial adenomatous polyposis, MUTYH-associated polyposis and Peutz–Jeghers syndrome.Materials and methods. The MLPA method was used for identification of large rearrangements. A total number of 135 patients was included in the study: 83 patients with a clinical diagnosis of “familial adenomatous polyposis”, 18 — with suspected MUTYH-associated polyposis, and 34 — with a clinical diagnosis of “Peutz–Jeghers syndrome”.Results. Seven large deletions and one large duplication in the APC gene were identified in 83 patients with classic familial adenomatous polyposis, with rate of large rearrangements 9.6 % (8/83). In 18 patients with suspected MUTYH-associated polyposis, no large rearrangements were found in the MUTYH gene. Four large deletions in the STK11 gene (12 %, 4/34) were detected in 34 patients with Peutz–Jeghers syndrome.Conclusion. For the first time, the expediency of including the method of detecting large rearrangements in routine DNA test list for Russian patients with various hereditary polyposis syndromes is demonstrated. Routine use of MLPA method makes it possible to increase the total frequency of detection of pathogenic variants in the APC and STK11 genes above 90 %. At the same time, the need for searching of large rearrangements in the MUTYH gene were not justified