Sudden Disappearances Research Articles

Narrating Loss in James Bradley’s "Clade" (2015); or, Introducing Arrested Narrative in Climate Fiction

In James Bradley’s futuristic novel of climate crises, Clade (2015), characters constructed to evoke empathy and readerly attachment, characters we expect to be further developed narratologically, are prone to sudden, unexpected and unexplained disappearances. The development of cared-for characters is thus ‘arrested’ at the level of narration. For readers, this is disarming and disconcerting. However, we find purpose in such acts of narratorial breakage in cli-fi like Clade. In contemporary stories of climate crises, which project environmental destruction, the loss of habitats and species, and severe disruption to human and nonhuman lives, the arrestation of a character’s development parallels a sense of environmental loss evoked at the level of storied content. Put another way, the sudden disappearance of character-story at the level of form imitates the sudden erasure of species, ecosystems and lived experience in the storyworld of Clade. We call such narratological innovation arrested narrative. In this essay we define and describe the appearance and function of arrested narrative in Clade, in some depth, as well as its emergence in two other novels of climate crises, Megan Hunter’s The End We Start From (2017) and Diane Cook’s The New Wilderness (2020). While investigations into narrative form in stories of the Anthropocene are not new, ecocritical literary scholarship remains largely focussed on story-level content. This examination of the way arrests in narrative discourse parallel environmental ruptures at the level of content, in selected cli-fi, is aimed at contributing to the emerging field of “econarratology” (James), concerned with the study of the workings of both form and content in ecocritical narratives.

The Americanization of conventional gothic elements in James Fenimore cooper’s The pathfinder

This paper examines the ways through which Cooper Americanizes the conventional gothic elements and techniques in The Pathfinder. It suggests that Cooper substitutes the American wilderness for the traditional castle or monastery used in European gothic fiction. With its atmosphere of threat and danger, the American wilderness is described as a gothic setting which produces feelings of fear and terror in the characters. Throughout the novel, Mabel Dunham and her companions feel insecure and uncertain in the wild and terrifying American natural landscapes. Cooper’s use of suspense and the sublime emphasize the gothic aspect of the American wilderness. In his adaptation of the gothic techniques to an American setting, Cooper also substitutes the Native Americans for the traditional ghosts and specters. This paper suggests that the savagery and hellishness of Cooper’s Indians make them as frightening as these mysterious apparitions. Their deviltry and ruthlessness intensify the characters’ feelings of terror and heighten the gothic atmosphere of the American wilderness. They are described as spectral-looking figures whose sudden appearances and disappearances make them seem like goblins. Considering the use of distinctively native elements and materials, this paper argues that Cooper transforms the gothic mode by adapting it to the American environment.

Vision-based localization of the center of mass of large space debris via statistical shape analysis

The current overpopulation of artificial objects orbiting the Earth has increased the interest of the space agencies on planning missions for de-orbiting the largest inoperative satellites. Since this kind of operations involves the capture of the debris, the accurate knowledge of the position of their center of mass is a fundamental safety requirement. As ground observations are not sufficient to reach the required accuracy level, this information should be acquired in situ just before any contact between the chaser and the target. Some estimation methods in the literature rely on the usage of stereo cameras for tracking several features of the target surface. The actual positions of these features are estimated together with the location of the center of mass by state observers. The principal drawback of these methods is related to possible sudden disappearances of one or more features from the field of view of the cameras. An alternative method based on 3D Kinematic registration is presented in this paper. The method, which does not suffer of the mentioned drawback, considers a preliminary reduction of the inaccuracies in detecting features by the usage of statistical shape analysis.

Aging-time-resolvedin situmicrostructural investigation of tin films electroplated on copper substrates, applying two-dimensional-detector X-ray diffraction

Pure thin tin films, electroplated on copper substrates, were investigated byin situX-ray diffraction analysis during room-temperature aging, using a laboratory diffractometer equipped with a two-dimensional detector. Diffraction spots of single Sn grains in the Sn film could be observed and traced over time by using the diffraction method adopted. For the as-deposited specimens, striking changes of the Sn reflection spots, concerning their position and intensity, as well as sudden appearances and disappearances of additional diffraction spots, were observed. This could be ascribed to local microstructural changes in the films such as grain rotation, grain growth and grain dissolution. In contrast to the as-deposited specimens, so-called post-baked specimens (i.e.annealed at 423 K for 1 h after layer deposition) exhibited a stable microstructure. The results obtained are discussed with respect to their relevance for the Sn whisker-growth phenomenon.

Critical conditions of saddle-node bifurcations in switching DC–DC converters

Although existence of multiple periodic orbits in some DC–DC converters have been known for decades, linking the multiple periodic orbits with the saddle-node bifurcation (SNB) is rarely reported. The SNB occurs in popular DC–DC converters, but it is generally reported as a strange instability. Recently, design-oriented instability critical conditions are of great interest. In this article, average, sampled-data and harmonic balance analyses are applied and they lead to equivalent results. Many new critical conditions are derived. They facilitate future research on the instability associated with multiple periodic orbits, sudden voltage jumps or disappearances of periodic orbits observed in DC–DC converters. The effects of various converter parameters on the instability can be readily seen from the derived critical conditions. New Nyquist-like plots are also proposed to predict or prevent the occurrence of the instability.

Bifurcation boundary conditions for current programmed PWM DC–DC converters at light loading

Three types of bifurcations (instabilities) in the PWM DC–DC converter at light loading under current mode control in continuous-conduction mode (CCM) or discontinuous-conduction mode (DCM) are analysed: saddle-node bifurcation (SNB) in CCM or DCM, border-collision bifurcation during the CCM–DCM transition, and period-doubling bifurcation in CCM. Different bifurcations occur in some particular loading ranges. Bifurcation boundary conditions separating stable regions from unstable regions in the parametric space are derived. A new methodology to analyse the SNB in the buck converter based on the peak inductor current is proposed. The same methodology is applied to analyse the other types of bifurcations and converters. In the buck converter, multiple stable/unstable CCM/DCM steady-state solutions may coexist. Possibility of multiple solutions deserves careful study, because an ignored solution may merge with a desired stable solution and make both disappear. Understanding of SNB can explain some sudden disappearances or jumps of steady-state solutions observed in switching converters.

Dynamic and Thermal Disappearance of Prominences and Their Geoeffectiveness

This paper is a qualitative study of 42 events of solar filament/prominence sudden disappearances (“disparitions brusques”; henceforth DBs) around two solar minima, 1985 – 1986 and 1994. The studied events were classified as 17 thermal and 25 dynamic disappearances. Associated events, i.e. coronal mass ejections (CMEs), type II bursts, evolution of nearby coronal holes, as well as solar wind speed, and geomagnetic disturbances are discussed. We have found that about 50% of the thermal DBs with adjacent (within 15° from the DB) coronal holes were associated with CMEs within a selected time window. All the studied thermal disappearances with adjacent coronal holes or accompanied by dynamic disappearances were associated with weak and medium geomagnetic storms. Also, nearly 64% of dynamic DBs were associated with CMEs. Ten (40%) dynamic disappearances were associated with intense geomagnetic storms, even when no CMEs was reported, six (24%) dynamic disappearances corresponded to extreme storms, and five (20%) corresponded to medium geomagnetic storms. The extreme geomagnetic storms appeared to be related to combined events, involving dynamic disappearances with adjacent coronal holes or including thermal disappearances. Furthermore, the geomagnetic activity (Dst index) increased if the source was close to the central meridian (±30°). The highest interplanetary magnetic field (B), longest duration, lowest southward direction Bz component, and lowest Dst were highly correlated for all studied events. The Sun – Earth transit time computed from the starting time of the sudden disappearance and the time its effect was measured at Earth was about 4.3 days and was mainly well correlated with the solar wind speed measured in situ (daily value).

The Cat with the Yellow Star (review)

Reviewed by: The Cat with the Yellow Star Elizabeth Bush Rubin, Susan Goldman The Cat with the Yellow Star; by Susan Goldman Rubin and Ela Weissberger. Holiday House, 2006 [40p] ISBN 0-8234-1831-6$16.95 Reviewed from galleys R Gr. 3-6 At the culmination of Kristallnacht, Marketa Stein was ordered to Nazi headquarters; upon her return, she hustled herself and her two daughters, Ela (co-author Weissberger) and Ilona, out of Sudetenland to the relative security of Prague. Within a few years, that haven crumbled and the tiny family (Ela's father had disappeared at Nazi hands) was removed to Terezin, where, for most of the next four years, Ela would grow up in Room 28 of building L410 with an ever-rotating roster of roommates, [End Page 32] many of whom were eventually "invited" onto transports to the East. Although Weissberger's earliest memories pass by in slightly choppy flashes, the clarity with which she and Rubin describe life in Terezin makes the account riveting. Here a picture emerges not just of child victims who were necessarily fearful and confused by the lack of reliable nourishment, inconsistently enforced rules, and sudden disappearances, but also of strong-willed people who created a thriving culture within a system of brutal confinement. Teachers, artists, and musicians bent and broke every rule to keep minds and spirits vigorous. The highlight of this cooperative effort was the series of performances of the opera Brundibar, in which Ela and many of her friends participated, and which was deceptively touted by Nazi camp officials as "proof" to the Red Cross of their humane treatment of the Jews. Young readers will certainly be relieved to learn that Ela not only survives her ordeal but leaves Terezin with her immediate family and even reunites with several old friends years later in the United States. The superficially rosy outcome is tempered, however, by Rubin's clear reminder in an epilogue that of the 10,632 children sent to Terezin fewer than half survived, and of the many girls resident in Room 28, a mere fifteen survived. Source notes, and index, and an extensive list of resources (many noted as suitable for children) round out this gripping memoir. Copyright © 2006 The Board of Trustees of the University of Illinois

On the sudden disappearances of solar filaments and their relationship with coronal mass ejections

On the sudden disappearances of solar filaments and their relationship with coronal mass ejections

On the sudden disappearances of solar filamentsand their relationship with coronal mass ejections

Abstract Sudden disappearances of prominences/filaments were identified from the Prairie View Solar Observatory Hα imagesand Meudon Observatory spectroheliograms for the period January 1, 2000 to March 31, 2000. Three classes of disappearances were considered for the purpose of this study: eruptive, quasi-eruptive and vanishing filaments. The Hα events were compared with CME data from LASCO C2 and C3 coronographs aboard SOHO. Our study shows that the eruptive events are strongly associated with CMEs while the other types are not.

A flare-triggered heating of a quiescent filament

Using data obtained with the 20-cm Hα full-disk telescope at Big Bear Solar Observatory and Fe xii 195 A EIT on SOHO, we analyze a sudden disappearance event of a quiescent filament in detail. The filament was located along the common boundary of the active regions NOAA 9672 (S19 E13) and NOAA 9673 (N03 E18). The filament disappeared during a time interval between 17:59 UT and 19:47 UT on 22 October 2001 immediately after the onset of a major flare, which occurred in the active region NOAA 9672. At about 23:23 UT of the same day, the filament began to reappear in Hα and, after about 15 hours, the filament recovered to its steady state with its size being slightly smaller than that before its disappearance. This filament disappearance event belongs to the thermal type of sudden filament disappearances, which is caused by an input of additional heat. The heating mechanism that leads to sudden thermal disappearances of quiescent filaments is still not well understood. This simple event, due to the explicit cause and effect relationship between the flare and the disappearance of the filament, shows us that the flare triggered some kind of heating mechanism which continued several hours. The heat may come from the flare via heat conduction from its ribbon or from the excitation of dissipating Alfven waves. However, from the data analysis, we conclude that the flare triggered an in-situ heating, which is likely caused by magnetic reconnection.

Chaos and population disappearances in simple ecological models.

A class of truncated unimodal discrete-time single species models for which low or high densities result in extinction in the following generation are considered. A classification of the dynamics of these maps into five types is proven: (i) extinction in finite time for all initial densities, (ii) semistability in which all orbits tend toward the origin or a semistable fixed point, (iii) bistability for which the origin and an interval bounded away from the origin are attracting, (iv) chaotic semistability in which there is an interval of chaotic dynamics whose compliment lies in the origin's basin of attraction and (v) essential extinction in which almost every (but not every) initial population density leads to extinction in finite time. Applying these results to the Logistic, Ricker and generalized Beverton-Holt maps with constant harvesting rates, two birfurcations are shown to lead to sudden population disappearances: a saddle node bifurcation corresponding to a transition from bistability to extinction and a chaotic blue sky catastrophe corresponding to a transition from bistability to essential extinction.

Homologous sudden disappearances of transequatorial interconnecting loops in the solar corona

We have found a remarkable sequence of homologous disappearances of transequatorial X‐ray loops linking active regions. Each disappearance was closely associated with a major flare and coronal mass ejection (CME). In each case the flarings precede the disappearances and the CMEs. Mass estimates for the X‐ray loops are similar to CME masses. This, the timing of the disappearances, their morphology, and the homology of the events in the sequence, provide direct evidence for a new class of CME origins in the low corona. We also briefly report observations of features which we infer to be the soft X‐ray counterparts of shock waves emanating from the flare region. The inferred shocks appeared to play a vital role in the disappearances. Our results suggest that flare‐generated shock waves may destabilize large transequatorial loops, causing them to erupt.

Ask the Sun (review)

"Not so very long ago the Middle Kingdom had a sun whose name was Mao Zedong. He called China's children morning suns. Today I ask the sun." This epigraph begins Ask the Sun, a lyrical collection of short stories by Chinese poet and short-story writer He Dong, who lives in Norway, where she is a researcher at the University of Oslo. Born in Beijing in 1960, He Dong describes what it was like to be one of Mao's many "children," to grow up under the influence that he radiated across China. She is part of that generation whose childhood was marked by the sudden disappearances and reappearances of family members, by public humiliations and abrupt reversals of status, and by constant surveillance and self-censorship. It's no surprise that Mao's children became adults who ask the eternal question of childhood: why? The only person who can answer them is dead, so the question hangs in the background, like a dark sun, like the indelible memory of Mao himself.

Gravitational Lensing by Cold Dark Matter Catastrophes

Intrinsically cold particle dark matter inevitably creates halos with sharp discontinuities in projected surface density caused by the projection of fold catastrophes onto the sky. In principle, these imperfections can be detected and measured with gravitational lensing through discontinuities in image magnification and image structure. Lens solutions are discussed for the most common universal classes of discontinuities. Edges caused by cold particles such as condensed axions and thermal WIMPs are very sharp, respectively about $10^{-12}$ and $10^{-7}$ of the halo scale. Their structure can be resolved by stellar and quasi-stellar sources which show sudden changes in brightness or even sudden disappearances (sometimes within hours) as edges are crossed. Images of extended objects such as edge-on galaxies or jets can show sudden bends at an edge, or stretched, parity-inverted reflection symmetry about a sharp line. Observational strategies and prospects are briefly discussed.

Chance and chaos in population biology—Models of recurrent epidemics and food chain dynamics

In spite of their complex behaviour the dynamics of some ecological systems may be explained by deterministic laws of motion. This is clearly theoretically possible, because deductive approaches to the dynamics of ecological systems lead to nonlinear models and even very simple model ecosystems generate typically a rich spectrum of dynamics, ranging from coexisting periodic regimes to chaotic behaviour. The present study analyses the complex interplay between deterministic nonlinear dynamics and demographic stochasticity using two examples. Firstly, the search for chaos in ecology has drawn much attention to the analysis of recurrent outbreaks of childhood epidemics—in particular of measles infections—in large population centres. The second example is a compartmental model of a three-species food chain, where sudden population disappearances can be observed due to transient chaos. Our analysis lends support to the plausibility of chaos in population dynamics. However, for decreasing population size (increasing fluctuations) the distinction between chaos and stochasticity becomes more and more problematic. The interplay between deterministic dynamics and stochastic fluctuations, e.g. due to the integer structure of populations or a noisy environment, suggests an analysis combining methods from the theory of nonlinear dynamical systems as well as stochastic processes.

Periodicity and distribution of the sudden disappearances of solar prominences in the chromosphere

This paper presents the results of the study on the periodicity and the distribution of the sudden disappearance of the solar prominences (SD) on the chromosphere. The spectral analysis of the SD, from 1039 to 1762 Carrington rotation number, shows a typical period at 138 (∼10.3 yr) solar rotations in the northern hemisphere and at 153 (∼11.4 yr) solar rotations in the southern hemisphere of the Sun. The power spectral analysis of the asymmetry index yields a primary peak at 155 (∼11.6 yr) solar rotations. By plotting the distribution of SD along the Carrington longitude, it can be seen that the distribution of the SD is nearly uniform.

Periodicities in the north-south asymmetry of solar activity

This paper tries to cast additional evidence on the proposed periodic behaviour of the N-S asymmetry in sudden disappearances (SD) of solar prominences (Vizoso and Ballester, 1987). We have performed a Blackman-Tukey power spectrum of the values of the SD N-S asymmetry and the results shows a significant peak, above 95% confidence level, at 12.4 years, another peak at 2.3 years fails to be statistically significant. Moreover, power spectrum performed with the values of N-S asymmetry of flare number and flare index (Vizoso and Ballester (1987) display significant peaks, above 95% confidence level, around 3.1–3.2 years.

North-South asymmetry in sudden disappearances of solar prominences

This paper presents the results of a study of the N-S asymmetry in sudden disappearances (SD) of solar prominences during solar cycles 18–21, obtained as a part of a more extensive research on SD and reappearances during years 1931–1985 (Ballester, 1984). As can be seen, the N-S SD asymmetry curve is not in phase with the solar cycle and peaks about the time of solar minimum, the asymmetry reverses in sign during the solar maximum, being, this change of sign, coincident with the reversal of the Sun's magnetic dipole. The SD asymmetry curve can be fitted by a sinusoidal function with a period of eleven years. On the other hand, the SD asymmetry curve shows a strong coincidence with the N-S asymmetries presented by other solar activity manifestations as studied by different authors.

The engagement of new residents: a missing dimension in the evaluation of halfway houses for problem drinkers.

Residents (N = 29) and staff of a halfway house for problem drinkers in England were studied over 6 months to determine the cause of premature departure. Each new resident was interviewed in depth every week during his first 8 weeks in the house (or until he left if that occurred sooner), and the staff members were also interviewed weekly over the complete 6 months. The significant findings centered on two areas: staff's attitudes toward residents and residents' satisfaction with the house. The staff judged residents who subsequently left prematurely less positively overall, liked them less and spent less time with them. Residents who subsequently left prematurely were more dissatisfied with the lack of privacy, saw life as being better outside, judged the staff more negatively and felt generally that their expectations about the house had not been matched. The implications of these findings are discussed in terms of the notions of "sudden disappearances" from halfway houses, and of engagement of new residents. Conclusions about levels of staff training and support, and the "matching hypothesis are made.