Kinetic Electron and Ion Instability of the Lunar Wake Simulated at Physical Mass Ratio

The solar wind wake behind the moon is studied with 1D electrostatic particle-in-cell (PIC) simulations using a physical ion to electron mass ratio (unlike prior investigations); the simulations also apply more generally to supersonic flow of dense magnetized plasma past non-magnetic objects. A hybrid electrostatic Boltzmann electron treatment is first used to investigate the ion stability in the absence of kinetic electron effects, showing that the ions are two-stream unstable for downstream wake distances (in lunar radii) greater than about three times the solar wind Mach number. Simulations with PIC electrons are then used to show that kinetic electron effects can lead to disruption of the ion beams at least three times closer to the moon than in the hybrid simulations. This disruption occurs as the result of a novel wake phenomenon: the non-linear growth of electron holes spawned from a narrow dimple in the electron velocity distribution. Most of the holes arising from the dimple are small and quickly leave the wake, approximately following the unperturbed electron phase-space trajectories, but some holes originating near the center of the wake remain and grow large enough to trigger disruption of the ion beams. Non-linear kinetic-electron effects are therefore essential to a comprehensive understanding of the 1D electrostatic stability of such wakes, and possible observational signatures in ARTEMIS data from the lunar wake are discussed.Comment: 9 pages, 10 figure

Zero-Shot Learning -- A Comprehensive Evaluation of the Good, the Bad and the Ugly

Due to the importance of zero-shot learning, i.e. classifying images where there is a lack of labeled training data, the number of proposed approaches has recently increased steadily. We argue that it is time to take a step back and to analyze the status quo of the area. The purpose of this paper is three-fold. First, given the fact that there is no agreed upon zero-shot learning benchmark, we first define a new benchmark by unifying both the evaluation protocols and data splits of publicly available datasets used for this task. This is an important contribution as published results are often not comparable and sometimes even flawed due to, e.g. pre-training on zero-shot test classes. Moreover, we propose a new zero-shot learning dataset, the Animals with Attributes 2 (AWA2) dataset which we make publicly available both in terms of image features and the images themselves. Second, we compare and analyze a significant number of the state-of-the-art methods in depth, both in the classic zero-shot setting but also in the more realistic generalized zero-shot setting. Finally, we discuss in detail the limitations of the current status of the area which can be taken as a basis for advancing it.Comment: Accepted by TPAMI in July, 2018. We introduce Proposed Split Version 2.0 (Please download it from our project webpage). arXiv admin note: substantial text overlap with arXiv:1703.0439

Pulse oximeter with integrated management of childhood illness for diagnosis of severe childhood pneumonia at rural health institutions in Southern Ethiopia: results from a cluster-randomised controlled trial.

OBJECTIVE: To assess whether pulse oximetry improves health workers' performance in diagnosing severe childhood pneumonia at health centres in Southern Ethiopia. DESIGN: Parallel cluster-randomised trial. SETTING: Government primary health centres. PARTICIPANTS: Twenty-four health centres that treat at least one pneumonia case per day in Southern Ethiopia. Children aged between 2 months and 59 months who present at health facilities with cough or difficulty breathing were recruited in the study from September 2018 to April 2019. INTERVENTION ARM: Use of the Integrated Management of Childhood Illness (IMCI) algorithm and pulse oximeter. CONTROL ARM: Use of the IMCI algorithm only. PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome was the proportion of children diagnosed with severe pneumonia. Secondary outcomes included referred cases of severe pneumonia and treatment failure on day 14 after enrolment. RESULT: Twenty-four health centres were randomised into intervention (928 children) and control arms (876 children). The proportion of children with severe pneumonia was 15.9% (148 of 928 children) in the intervention arm and 3.9% (34 of 876 children) in the control arm. After adjusting for differences in baseline variables children in the intervention arm were more likely to be diagnosed as severe pneumonia cases as compared with those in the control arm (adjusted OR: 5.4, 95% CI 2.0 to 14.3, p=0.001). CONCLUSION: The combined use of IMCI and pulse oximetry in health centres increased the number of diagnosed severe childhood pneumonia. TRIAL REGISTRATION NUMBER: PACTR201807164196402

The highly rearranged mitochondrial genomes of the crabs Maja crispata and Maja squinado (Majidae) and gene order evolution in Brachyura

Abstract We sequenced the mitochondrial genomes of the spider crabs Maja crispata and Maja squinado (Majidae, Brachyura). Both genomes contain the whole set of 37 genes characteristic of Bilaterian genomes, encoded on both \u3b1- and \u3b2-strands. Both species exhibit the same gene order, which is unique among known animal genomes. In particular, all the genes located on the \u3b2-strand form a single block. This gene order was analysed together with the other nine gene orders known for the Brachyura. Our study confirms that the most widespread gene order (BraGO) represents the plesiomorphic condition for Brachyura and was established at the onset of this clade. All other gene orders are the result of transformational pathways originating from BraGO. The different gene orders exhibit variable levels of genes rearrangements, which involve only tRNAs or all types of genes. Local homoplastic arrangements were identified, while complete gene orders remain unique and represent signatures that can have a diagnostic value. Brachyura appear to be a hot-spot of gene order diversity within the phylum Arthropoda. Our analysis, allowed to track, for the first time, the fully evolutionary pathways producing the Brachyuran gene orders. This goal was achieved by coupling sophisticated bioinformatic tools with phylogenetic analysis

ACCELERATED LEARNING BERBANTUAN SOFTWARE MAPLE SEBAGAI UPAYA MENINGKATKAN KEMAMPUAN KOMUNIKASI MATEMATIS DAN MINAT BELAJAR SISWA SMA

Penelitian ini dilatarbelakangi oleh pentingnya kemampuan komunikasi matematis dan minat belajar. Namun kenyataan di lapangan menunjukkan bahwa kemampuan komunikasi matematisdan minat belajarsiswa masih rendah. Agar permasalahan tersebut dapat diatasi, diperlukan sebuah model pembelajaran yang dapatmeningkatkankemampuan komunikasi matematis dan minat belajarsiswa.Olehkarenaitu, dipilih modelAccelerated Learning Berbantuan Software Maple. Penelitian ini bertujuan untuk menelaahpeningkatan kemampuan komunikasi matematis dan minat belajarsiswa, danmenelaahhubunganantara kemampuan komunikasi dan minat belajar.Penelitianinimerupakanpenelitiankuasieksperimendenganpretest-postest control group design. Populasi pada penelitian ini adalah seluruh siswa kelas X pada salah satu SMA Negeri di Kota Purwokerto. Sampel terdiri dari dua kelas yang dipilih secara purposive sampling.Instrumen yang digunakan berupa tes kemampuan komunikasi matematis dan angket minat belajar, lembar observasi, serta pedoman wawancara. Analisis data dilakukan secara kuantitatif.Analisis data tersebutmenggunakanMann-Whitney U Testdan uji asosiasi Chi Square. Berdasarkan analisis data, ditemukan bahwa: (1)pencapaian kemampuan komunikasi matematis siswa yang memperoleh Accelerated LearningBerbantuanSoftware Maplelebih baik daripada siswa yang memperoleh pembelajaran biasa;(2) peningkatan kemampuan komunikasi matematis siswa yang memperoleh Accelerated LearningBerbantuanSoftware Maplelebih baik daripada siswa yang memperoleh pembelajaran biasa, (3) pencapaian kemampuan minat belajar siswa yang memperoleh Accelerated LearningBerbantuanSoftware Maplelebih baik daripada siswa yang memperoleh pembelajaran biasa; (4) peningkatan kemampuan minat belajar siswa yang memperoleh Accelerated LearningBerbantuanSoftware Maplelebih baik daripada siswa yang memperoleh pembelajaran biasa; dan(5) terdapat asosiasi antara kemampuan komunikasi dan minat belajarsiswadengan kategori rendah. ---------- This research was motivated by the importance of mathematical communication learning interest of students. Mathematical communication ability and learning interest of students is still low. In order that this problemscan be solved, alearning modelthatcan enhancemathematical communication and learning interest ofstudents is required.In this research, Maple-Assisted Accelerated Learning was selected. This studyaims to analyzetheenhancement of mathematical communication learning interest of students, and to analyzetheassociationbetween mathematical communication ability andlearning interest of students. This research was aquasi-experimentalwithpretest-posttest control group design. The population was students at tenth gradein one of senior high schools in Purwokerto, Central Java. The sample consisted oftwoclasses which wasselected bypurposivesampling. This research used fourinstruments: testof mathematicalcommunication ability, learning interestquestionnaire, observation sheets, and interview guide.Data analyzed was done quantitatively. The data were analyzed by usingMann-Whitney U TestandChi Squaren test. Based on the data analyze, it is found that: (1) the achievement of mathematical communication ability of students who receivedthe Maple-Assisted Accelerated Learning is betterthan the achievement of students who receivedconventionallearning;(2) The enhancement of mathematical communication ability of students who receivedthe Maple-Assisted Accelerated Learning is betterthan the enhancement of students who receivedconventionallearning; (3)the achievement oflearning interestability of students who receivedthe Maple-Assisted Accelerated Learning is betterthan the achievement of students who receivedconventionallearning; (4)the enhancement oflearning interestof students who receivedthe Maple-Assisted Accelerated Learning is betterthan the enhancement of students who receivedconventionallearning; and(5) there is anassociation between students’ mathematical communication ability and learning interest of student

Optimal multi-dimensional stochastic harvesting with density-dependent prices

We prove a verification theorem for a class of singular control problems which model optimal harvesting with density-dependent prices or optimal dividend policy with capital-dependent utilities. The result is applied to solve explicitly some examples of such optimal harvesting/optimal dividend problems. In particular, we show that if the unit price decreases with population density, then the optimal harvesting policy may not exist in the ordinary sense, but can be expressed as a “chattering policy”, i.e. the limit as Δ x and Δ t go to 0 of taking out a sequence of small quantities of size Δ x within small time periods of size Δ t.</p