55 research outputs found
Electromagnetic field and radiation for a charge moving along a helical trajectory inside a waveguide with dielectric filling
We investigate the electromagnetic field generated by a point charge moving
along a helical trajectory inside a circular waveguide with conducting walls
filled by homogeneous dielectric. The parts corresponding to the radiation
field are separated and the formulae for the radiation intensity are derived
for both TE and TM waves. It is shown that the main part of the radiated quanta
is emitted in the form of the TE waves. Various limiting cases are considered.
The results of the numerical calculations show that the insertion of the
waveguide provides an additional mechanism for tuning the characteristics of
the emitted radiation by choosing the parameters of the waveguide and filling
medium.Comment: 17 pages, 9 figures, discussion, graphs, and references adde
Autoimmune polyglandular syndrome type I. Features of clinical manifestations, difficulties in diagnosis and methods of correction
Autoimmune polyglandular syndrome (APG) type I is an orphan disease with autosomal recessive inheritance caused by mutations in the autoimmune regulator gene (AIRE); the disease onset typically occurs in childhood. The disease is characterized by a wide variety of clinical manifestations with a certain stage in the manifestation of individual symptoms. The rare occurrence of this pathology determines its late diagnosis, which can lead to the decompensated life-threatening conditions and an unfavorable outcome. Widely informing pediatric specialists will contribute to the development of a diagnostic algorithm for timely verifying the disease from the moment its first clinical manifestations appear, and will improve the quality and life expectancy of the patients
Status of Muon Collider Research and Development and Future Plans
The status of the research on muon colliders is discussed and plans are
outlined for future theoretical and experimental studies. Besides continued
work on the parameters of a 3-4 and 0.5 TeV center-of-mass (CoM) energy
collider, many studies are now concentrating on a machine near 0.1 TeV (CoM)
that could be a factory for the s-channel production of Higgs particles. We
discuss the research on the various components in such muon colliders, starting
from the proton accelerator needed to generate pions from a heavy-Z target and
proceeding through the phase rotation and decay ()
channel, muon cooling, acceleration, storage in a collider ring and the
collider detector. We also present theoretical and experimental R & D plans for
the next several years that should lead to a better understanding of the design
and feasibility issues for all of the components. This report is an update of
the progress on the R & D since the Feasibility Study of Muon Colliders
presented at the Snowmass'96 Workshop [R. B. Palmer, A. Sessler and A.
Tollestrup, Proceedings of the 1996 DPF/DPB Summer Study on High-Energy Physics
(Stanford Linear Accelerator Center, Menlo Park, CA, 1997)].Comment: 95 pages, 75 figures. Submitted to Physical Review Special Topics,
Accelerators and Beam
Muon (g-2) Technical Design Report
The Muon (g-2) Experiment, E989 at Fermilab, will measure the muon anomalous magnetic moment a factor-of-four more precisely than was done in E821 at the Brookhaven National Laboratory AGS. The E821 result appears to be greater than the Standard-Model prediction by more than three standard deviations. When combined with expected improvement in the Standard-Model hadronic contributions, E989 should be able to determine definitively whether or not the E821 result is evidence for physics beyond the Standard Model. After a review of the physics motivation and the basic technique, which will use the muon storage ring built at BNL and now relocated to Fermilab, the design of the new
experiment is presented. This document was created in partial fulfillment of the requirements necessary to obtain DOE CD-2/3 approval
Сопоставление рентгенологической и патоморфологической картины легких у пациентов с COVID-19
Aim. Compare radiological patterns of COVID-19 pneumonia with pulmonary histology in deceased patients.Materials and methods. The analysis of recent lifetime CT studies of deceased patients was performed with the identification of all existing and leading CT symptoms, including “ground glass”, “crazy paving”, consolidation, as well as the symptom complex (pattern) of organizing pneumonia. Based on the CT symptoms, we selected the target points for taking the specimens by 3-D reconstructions. At the autopsy the lungs were entirely fixed into the front and then marked on CT sections cut from 1 to 3 pieces that were placed in paraffin and processed according to the standard technique, stained with hematoxylin and eosin and fuchsin-facelina. The specimens were analyzed by identifying all available histology changes and selecting the leading one.Results. 45 targeted pieces of lung tissue were obtained from 14 deceased COVID-19 patients (7 men/ 7 women), with an average age of 77.1 ± 12.9 (49–90 years). In deceased patients with the presence of the "ground glass" symptom, in most cases (57.1%) revealed an increase in intra-alveolar cellularity, hyaline membranes, desquamation of the alveolar epithelium and infiltration of the interalveolar septum by lymphocytes, which corresponds to the exudative phase of diffuse alveolar damage (DAP). Mosaic histological changes with alternation of filled alveoli (intraalveolar edema, clusters of red blood cells, macrophages, lymphocytes) and air alveoli were detected from the areas of “crazy paving” zones. Several cases demonstrated interstitial edema and lymphoid infiltration of interalveolar partitions of different severity without their thickening. Areas of consolidation were histologically represented by extensive intraalveolar hemorrhages and / or typical zones of hemorrhagic infarcts in 45.5% of cases. Perilobular consolidation, subpleural cords, symptoms of “halo” and “reverse halo”, which we considered as part of the symptom complex of organizing pneumonia in 43% of cases, morphologically corresponded to organizing pneumonia (the proliferative phase of DAP), as well as to distelectases.Conclusion. Comparison of CT patters and post-mortem pulmonary histology in COVID-19 deceased patients demonstrated that CT symptoms and patterns correspond to certain morphological changes of different phases of DAP.Цель исследования: сопоставить рентгенологические паттерны COVID-19 с гистологическими изменениями у умерших.Материал и методы. Проведен анализ последних прижизненных КТ-исследований умерших пациентов с выделением всех имеющихся и ведущего КТ-симптомов, включая “матовое стекло”, “булыжная мостовая”, консолидация, а также симптомокомплекс (паттерн) организующейся пневмонии. На основании выделенных КТ-симптомов были выбраны прицельные точки взятия материала при помощи построения трехмерных реконструкций. На аутопсии фиксированные целиком легкие разрезались фронтально, далее из обозначенных на компьютерной томограмме участков вырезали от 1 до 3 кусочков, которые заливались в парафин и обрабатывались по общепринятой методике с последующей окраской срезов толщи- ной 3–5 мкм гематоксилином и эозином, пикрофуксин-фукселином. Анализ материала проводили путем выявления всех имеющихся патоморфологических изменений с выделением ведущего из них.Результаты. Были получены 45 прицельно взятых кусочков ткани легкого от 14 умерших (7 мужчин/ 7 женщин), средний возраст 77,1 ± 12,9 (49–90) года. У умерших пациентов с наличием симптома “матово- го стекла” при КТ в большинстве случаев (57,1%) были выявлены увеличение числа клеток в просветах альвеол (внутриальвеолярная клеточность), гиалиновые мембраны, десквамация альвеолярного эпителия и инфильтрация лимфоцитами межальвеолярных перегородок, что может соответствовать признакам экссудативной фазы диффузного альвеолярного повреждения (ДАП). Из участков, обозначенных как зоны “булыжной мостовой”, были выявлены мозаичные гистологические изменения с чередованием заполненных альвеол (внутриальвеолярный отек, скопления эритроцитов, макрофагов, лимфоцитов) и воздушных альвеол, местами при наличии интерстициального отека и лимфоидной инфильтрации межальвеолярных перегородок разной степени выраженности без их утолщения. Участки консолидации гистологически были представлены обширными внутриальвеолярными кровоизлияниями и/или типичными зонами геморрагических инфарктов в 45,5% случаев. Перилобулярная консолидация, субплевральные тяжи, симптомы “ободка” и “обратного ободка”, которые мы расценивали в рамках симптомокомплекса организующейся пневмонии, на компьютерной томограмме в 43% случаев морфологически соответствовали организующейся пневмонии (пролиферативная фаза ДАП), а также дистелектазам.Заключение. При попытке рентгенопатоморфологического сопоставления у пациентов с COVID-19 с поражением легких нами было показано, что различные симптомы и паттерны при КТ соответствуют определенным морфологическим изменениям в различные фазы ДАП
Measurement of the Positive Muon Anomalous Magnetic Moment to 0.46 ppm
We present the first results of the Fermilab Muon g-2 Experiment for the
positive muon magnetic anomaly . The anomaly is
determined from the precision measurements of two angular frequencies.
Intensity variation of high-energy positrons from muon decays directly encodes
the difference frequency between the spin-precession and cyclotron
frequencies for polarized muons in a magnetic storage ring. The storage ring
magnetic field is measured using nuclear magnetic resonance probes calibrated
in terms of the equivalent proton spin precession frequency
in a spherical water sample at 34.7C. The
ratio , together with known fundamental
constants, determines
(0.46\,ppm). The result is 3.3 standard deviations greater than the standard
model prediction and is in excellent agreement with the previous Brookhaven
National Laboratory (BNL) E821 measurement. After combination with previous
measurements of both and , the new experimental average of
(0.35\,ppm) increases the
tension between experiment and theory to 4.2 standard deviationsComment: 10 pages; 4 figure
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