Earth Potential Electrodes in Permafrost and Tundra

Introduction : During the past two years, the authors installed a number of electrodes in the permafrost and tundra area of Point Barrow to obtain earth potential data. As ground temperatures decreased during the winter, the resistances of the first set of electrodes increased by several orders of magnitude and thus became useless. A second set of electrodes, with sodium chloride incorporated in the fill, proved entirely adequate for recording earth potentials. The installations and procedure for determining electrode resistances are described herein. Electrode resistance data versus time and ground temperatures are also presented.Ye

Rapid Fluctuations in Earth-Currents at College

An unusual type of earth-current variation is regularly observed in the College records. The phenomena consist of more or less regular fluctuations with range from a few mv/km to more than 1000 mv/km, and periods ranging upwards from 6 seconds. The fluctuations may continue from a few minutes to several hours. They have a strong diurnal variation at College with a broad maximum at 0600 local time. The fluctuations also occur at a site about 100 km southeast of College, but are not observed at Barrow« Thus these rapid fluctuations display characteristics quite different from the previously classified magnetic and earth-current continuous pulsations, pc's, and train pulsations, pt's. Special equipment was devised to count and record the period of the fluctuations on a continuous basis. Typical rapid, fluctuation, traces.and charts showing their activity patterns are presented.This research is sponsored by the Geophysics Research Directorate, Air Force Cambridge Research Center, Air Research and Development Command under Contract No. AF 19(604)-3075 and by a grant from the National Science Foundation.Abstract -- Introduction -- Equipment : Geographic location of electrode field ; Stray electric fields ; Electrodes ; Lines ; Recorders ; Cycle counting equipment -- Records and Scaling : Rapid fluctuation records ; Rapid fluctuation at College - selected days ; Rapid fluctuation activity - February 1958 -- Diurnal variation in rapid fluctuation -- Diurnal variation in amplitude and frequency activity ; Rapid fluctuation frequency and period ; Rapid fluctuations at College and at Barrow -- Discussion : Comparison of earth-current rapid fluctuations with geomagnetic pulsations ; Comparison with other earth-current pulsation studies ; Diurnal Variation in amplitude and fluctuation frequency activity at College ; Generation of earth-current rapid fluctuation -- Summary -- Bibliography -- FiguresYe

Cognitive Structures of Good and Poor Novice Problem Solvers in Physics

The way knowledge is organized in memory is generally expected to relate to the degree of success in problem solving. In the present study, we investigated whether good novice problem solvers have their knowledge arranged around problem types to a greater extent than poor problem solvers have. In the subject of physics (electricity and magnetism), 12 problem types were distinguished according to their underlying physics principles. For each problem type, a set of elements of knowledge containing characteristics of the problem situation, declarative knowledge, and procedural knowledge was constructed. All of the resulting 65 elements were printed on cards, and first-year university students in physics ( N = 47) were asked to sort these cards into coherent piles shortly after they had taken an examination on electricity and magnetism. Essentially, good novice problem solvers sorted the cards according to problem types; the sorting by the poor problem solvers seemed to be determined to a greater extent by the surface characteristics of the elements. We concluded than an organization of knowledge around problem types might be highly conducive to good performance in problem solving by novice problem solvers

Probing the scotogenic FIMP at the LHC

We analyse the signatures at the Large Hadron Collider (LHC) of the scotogenic model, when the lightest Z2-odd particle is a singlet fermion and a feebly interacting massive particle (FIMP). We further assume that the singlet fermion constitutes the dark matter and that it is produced in the early Universe via the freeze-in mechanism. The small couplings required to reproduce the observed dark matter abundance translate into decay-lengths for the next-to-lightest Z2-odd particle which can be macroscopic, potentially leading to spectacular signatures at the LHC. We characterize the possible signals of the model according to the spectrum of the Z2-odd particles and we derive, for each of the cases, bounds on the parameters of the model from current searches.Comment: 19 pages, 7 figures; typos corrected; published versio

Borrowing, Avoidance, and the Development of the Zulu Click Inventory

The Zulu language of eastern South Africa is remarkable both for being one of the few languages known to have incorporated lingual-ingressive “click” sounds into its phonology through language contact, and for the unusually thorough and comprehensive nature of this incorporation, which has been noted by scholars at least since the 19th century (Döhne 1857). To help explain this, Herbert (1990a) proposes that isihlonipho, a sociolinguistic avoidance custom which the Zulu people have in common with neighboring Bantu peoples, played a decisive role in the integration of clicks into these languages. To date, however, the question of the structure of the click inventories which this integration produced – that is, why Bantu “click languages” utilize certain clicks and not others – has not been addressed. This is particularly worthy of consideration in light of the fact that these Bantu click inventories do not resemble phonetically the click inventories of the southern African non-Bantu (SANB) languages from which they are supposed to have “borrowed” their clicks (Beach 1938:82-88). This thesis takes up the question of the Zulu click inventory’s structure through a consideration of the synchronic processes, isihlonipho and word borrowing, which are believed to have historically contributed to the integration of clicks into Zulu. I conclude that the Zulu click inventory should be seen as emergent within Zulu from the parallel operation of these processes, and not as “borrowed” as one unit from SANB languages. I also propose a new characterization of the isihlonipho process counter to its traditional analysis as “consonant replacement,” and discuss the implications of this study for the understanding of isihlonipho as a historical phenomenon.No embargoAcademic Major: Linguistic

Addition of an anti-staphylococcal beta lactam to standard antibiotic therapy does not decrease 90-day mortality of MRSA bacteremia versus standard therapy alone

A clinical decision report appraising Tong SYC, Lye DC, Yahav D, et al. Effect of vancomycin or daptomycin with vs without an antistaphylococcal β-lactam on mortality, bacteremia, relapse, or treatment failure in patients with MRSA bacteremia: a randomized clinical trial. JAMA. 2020;323(6):527–537. https://doi.org/10.1001/jama.2020.0103 for a patient with multiple comorbidities including heart failure, severe aortic regurgitation, aortic aneurysm and intellectual disability being treated for MRSA bacteremia who is intubated in the ICU