AS-204/LM-1 launch vehicle operational flight trajectory

Apollo Saturn-204/LM-1 launch vehicle operational flight trajector

Lensing of Fast Radio Bursts by Plasma Structures in Host Galaxies

Plasma lenses in the host galaxies of fast radio bursts (FRBs) can strongly modulate FRB amplitudes for a wide range of distances, including the $\sim$ Gpc distance of the repeater FRB121102. To produce caustics, the lens' dispersion-measure depth (${\rm DM}_{\ell}$), scale size ($a$), and distance from the source ($d_{\rm sl}$) must satisfy ${\rm DM}_{\ell} d_{\rm sl} / a^2 \gtrsim 0.65~ {\rm pc^2 \ AU^{-2} \ cm^{-3}}$. Caustics produce strong magnifications ($\lesssim 10^2$) on short time scales ($\sim$ hours to days and perhaps shorter) along with narrow, epoch dependent spectral peaks (0.1 to 1~GHz). However, strong suppression also occurs in long-duration ($\sim$ months) troughs. For geometries that produce multiple images, the resulting burst components will arrive differentially by $< 1~\mu$s to tens of ms and they will show different apparent dispersion measures, $\delta{\rm DM}_{\rm apparent} \sim 1$ pc cm$^{-3}$. Arrival time perturbations may mask any underlying periodicity with period $\lesssim 1$ s. When arrival times differ by less than the burst width, interference effects in dynamic spectra are expected. Strong lensing requires source sizes smaller than $({\rm Fresnel~scale)^2} / a$, which can be satisfied by compact objects such as neutron star magnetospheres but not by AGNs. Much of the phenomenology of the repeating fast radio burst source FRB121102 is similar to lensing effects. The overall picture can be tested by obtaining wideband spectra of bursts (from $<1$ to 10 GHz and possibly higher), which can also be used to characterize the plasma environment near FRB sources. A rich variety of phenomena is expected from an ensemble of lenses near the FRB source. We discuss constraints on densities, magnetic fields, and locations of plasma lenses related to requirements for lensing to occur.Comment: 11 pages, 7 figures, submitted to the Astrophysical Journa

VLA Observations of Single Pulses from the Galactic Center Magnetar

We present the results of a 7-12 GHz phased-array study of the Galactic center magnetar J1745-2900 with the Karl G. Jansky Very Large Array (VLA). Using data from two 6.5 hour observations from September 2014, we find that the average profile is comprised of several distinct components at these epochs and is stable over $\sim$day timescales and $\sim$GHz frequencies. Comparison with additional phased VLA data at 8.7 GHz shows significant profile changes on longer timescales. The average profile at 7-12 GHz is dominated by the jitter of relatively narrow pulses. The pulses in each of the four main profile components seen in September 2014 are uncorrelated in phase and amplitude, though there is a small but significant correlation in the occurrence of pulses in two of the profile components. Using the brightest pulses, we measure the dispersion and scattering parameters of J1745-2900. A joint fit of 38 pulses gives a 10 GHz pulse broadening time of $\tau_{\rm sc, 10} = 0.09 \pm 0.03~\rm ms$ and a dispersion measure of ${\rm DM} = 1760^{+2.4}_{-1.3}~{\rm pc~cm}^{-3}$. Both of these results are consistent with previous measurements, which suggests that the scattering and dispersion measure of J1745-2900 may be stable on timescales of several years.Comment: 20 pages, 10 figures, published in Ap

Стволы с маркировкой Глок – анализ индивидуальных и подклассовых (подгрупповых) признаков

Glock Inc. recently replaced the Enhanced Bullet Identification System (EBIS) with what Glock refers to as the Glock Marking Barrel. Casts and test fired bullets from thirty-five Glock Marking Barrels were evaluated for subclass and individual characteristics. It was determined that the barrels had subclass carryover from barrel to barrel manufactured using the same mandrel. However, identification of a fired bullet back to the barrel/firearm that fired it was still possible using specific areas of the fired bullet. Due to the fact that this type of barrel will be used in all models of Glock pistols, an examiner should be aware of which areas of a fired bullet may have a high potential for subclass characteristics.В статье кратко рассматривается эволюция устройства каналов стволов пистолетов Глок. Особое внимание уделяется конструкции канала ствола пистолета последнего поколения, в котором для облегчения проведения его идентификации по следам на выстреленных пулях к нарезам полигонального профиля были добавлены особые элементы – «рельсы». Рассмотрены особенности следов, оставляемых этими элементами на выстреленных пулях. Обсуждается проблема подклассовых (подгрупповых) признаков, возможность их присутствия в следах канала ствола на пулях, выстреленных из разных экземпляров пистолетов Глок, что проиллюстрировано фотографиями совпадающих трасс в каналах стволов разных пистолетов.Материал был подготовлен сотрудниками криминалистической лаборатории офиса шерифа округа Палм Бич (Флорида, США) – Омаром Феликсом, Джимми Палма и Тоддом Вартоном – членами международной ассоциации экспертов в области исследования огнестрельного оружия и следов инструментов (the Association of Firearm and Tool Mark Examiners – AFTE). Омар Феликс также является председателем специализированного комитета ассоциации по вопросам изучения следов обработки деталей оружия и подклассовых (подгрупповых) признаков. Оригинальная статья была опубликована в 2016 году в третьем номере AFTE Journal – американском ежеквартальном издании ассоциации AFTE. В журнале «Теория и практика судебной экспертизы» статья публикуется с согласия всех авторов и главного редактора AFTE Journal.Ассоциация действует с 1969-го года, ее членами являются более 1300 экспертов-баллистов из 39 стран мира, включая Россию. В AFTE существует комитет по международным связям и ресурсам, который оказывает содействие желающим вступить в ассоциацию или опубликовать статьи в журнале АFTE. Связаться с представителями комитета можно по электронной почте [email protected].Кроме издания журнала ассоциация AFTE проводит ежегодные шестидневные конференции, включающие учебные семинары, собирает и систематизирует информацию, необходимую для работы экспертов в области судебной баллистики: базы данных параметров каналов стволов различных моделей оружия, следов оружия на стреляных гильзах, маркировок патронов и т. д. Эта и другая актуальная информация представлена на сайте ассоциации www.afte.org

The Changing Eigenfrequency Continuum during Geomagnetic Storms:Implications for Plasma Mass Dynamics and ULF Wave Coupling

Geomagnetic storms are one of the most energetic space weather phenomena. Previous studies have shown that the eigenfrequencies of ultralow frequency (ULF) waves on closed magnetic field lines in the inner magnetosphere decrease during storm times. This change suggests either a reduction in the magnetic field strength and/or an increase in its plasma mass density distribution. We investigate the changes in local eigenfrequencies by applying a superposed multiple‐epoch analysis to cross‐phase spectra from 132 geomagnetic storms. Six ground magnetometer pairs are used to investigate variations from approximately 3 4, the eigenfrequencies decrease by as much as 50% relative to their quiet time values. Both a decrease in magnetic field strength and an increase in plasma mass density, in some locations by more than a factor of 2, are responsible for this reduction. The enhancement of the ring current and an increase in oxygen ion density could explain these observations. At L < 4, the eigenfrequencies increase due to the decrease in plasma mass density caused by plasmaspheric erosion

Fargo: Seeing the significance of style in television poetics?

This article explores the adaptation of the original film to television and how a strain of art or independent cinema contributed to the development of the first series of Fargo (2014–present). By making this comparison, the transition to television of the storyworld established by the Coen brothers raises questions about who is talking in the TV drama – the Coens or makers of the series. At the same time, Fargo can be more easily explained and understood as a strategy by writers, directors and producers that further complicate ideas to do with Noah Hawley, as its showrunner and the show’s single-author status. In Fargo, fidelity to the Coen brothers as a testament to the memory of the original film is set against questions about the reliability of storytelling using complex imagery. By alternating between different levels of narration signified by its stylistic tonal qualities, Fargo succeeds in producing multiple meanings, representations and effects that call attention to textual pleasures in the complex television series

Native valve endocarditis due to Micrococcus luteus: a case report and review of the literature

<p>Abstract</p> <p>Introduction</p> <p><it>Micrococcus luteus </it>endocarditis is a rare case of infective endocarditis. A total of 17 cases of infective endocarditis due to <it>M luteus </it>have been reported in the literature to date, all involving prosthetic valves. To the best of our knowledge, we describe the first case of native aortic valve <it>M luteus </it>endocarditis in an immunosuppressed patient in this report.</p> <p>Case report</p> <p>A 74-year-old Greek-Cypriot woman was admitted to our Internal Medicine Clinic due to fever and malaise and the diagnosis of aortic valve <it>M luteus </it>endocarditis was made. She was immunosuppressed due to methotrexate and steroid treatment. Our patient was unsuccessfully treated with vancomycin, gentamicin and rifampicin for four weeks. The aortic valve was replaced and she was discharged in good condition.</p> <p>Conclusions</p> <p>Prosthetic infective endocarditis due to <it>M luteus </it>is rare. To the best of our knowledge, we report the first case in the literature involving a native valve.</p

Global intravascular and local hyperoxia contrast phase-based blood oxygenation measurements

AbstractThe measurement of venous cerebral blood oxygenation (Yv) has potential applications in the study of patient groups where oxygen extraction and/or metabolism are compromised. It is also useful for fMRI studies to assess the stimulus-induced changes in Yv, particularly since basal Yv partially accounts for inter-subject variation in the haemodynamic response to a stimulus. A range of MRI-based methods of measuring Yv have been developed recently. Here, we use a method based on the change in phase in the MR image arising from the field perturbation caused by deoxygenated haemoglobin in veins. We build on the existing phase based approach (Method I), where Yv is measured in a large vein (such as the superior sagittal sinus) based on the field shift inside the vein with assumptions as to the vein's shape and orientation. We demonstrate two novel modifications which address limitations of this method. The first modification (Method II), maps the actual form of the vein, rather than assume a given shape and orientation. The second modification (Method III) uses the intra and perivascular phase change in response to a known change in Yv on hyperoxia to measure normoxic Yv in smaller veins. Method III can be applied to veins whose shape, size and orientation are not accurately known, thus allowing more localised measures of venous oxygenation. Results demonstrate that the use of an overly fine spatial filter caused an overestimation in Yv for Method I, whilst the measurement of Yv using Method II was less sensitive to this bias, giving Yv=0.62±0.03. Method III was applied to mapping of Yv in local veins across the brain, yielding a distribution of values with a mode of Yv=0.661±0.008