Acceleration Hypothesis Research Articles

Do geological records correlate with the supercontinent cycle?

Whether the supercontinent cycle (Sc) is the major process driving plate tectonics evolution has not been purposely investigated. If true, it would result in more geological records formed during each supercontinent assembly. In this study, a quantitative statistical approach is used to investigate this question. Six global geological datasets (GGDs) of carbonatite, zircon hafnium, kimberlite, metamorphism, monazite and zircon records are analyzed using Spearman’s correlation (ρs). Ranking the GGDs according to Spearman’s method allows them to be compared. Each GGD shows moderate to very strong correlations (0.5 < ρs < 0.9), with the metamorphism, monazite, zircon and zircon hafnium datasets displaying the most similarities. Each published supercontinent cyclicity (Sc 500 Myr, Sc 600 Myr, Sc 800 Myr and Sc acceleration) is then depicted according to its assembly timing. A second Spearman correlation performed with the four supercontinent cyclicities suggests that the Sc acceleration hypothesis best fits the geological archives (average ρs = 0.45), potentially supporting the supercontinent cycle as the first-order mechanism of plate tectonics evolution. Conversely, constant cyclicities result in weaker correlations (average ρs < 0.26), which could indicate significant decoupling of the geological archives and the supercontinent cycle. Moreover, Sc 600 surprisingly shows no correlation with the six GGDs (average ρs = 0.04). The implications for the supercontinent cycle and the limits of Spearman’s correlation are also discussed.

Studying the role of supernova remnants as cosmic ray PeVatron with LHAASO observations

It is commonly believed that galactic cosmic rays are produced in supernova remnants (SNRs) and accelerated via a diffusive shock acceleration (DSA) mechanism in supernova blast waves driven by expanding SNRs. The latest theoretical advancement of the diffusive shock acceleration hypothesis in SNRs shows that cosmic rays may be accelerated up to the knee energy of the observed cosmic ray spectrum under the amplified magnetic field scenario. There is, however, no empirical evidence to support SNRs as sources of hadrons with energies larger than a few tens of TeV. Very recently, LHAASO observatory reported the very high-energy gamma ray emission between TeV to PeV energy range from two SNRs, Cassiopeia A and IC 443. Above 25 TeV energies, non-detection of gamma-ray flux by LHAASO yields a strong upper limit. In this work, we investigate the implications of the acceleration of cosmic ray protons in the SNR on energetic gamma rays produced in the hadronic interaction of cosmic rays with ambient matter. Our findings imply that when we consider the highest attainable energy of cosmic ray protons in the SNRs to be about 100 TeV, the observed gamma-ray spectra from the two SNRs can be described consistently. Therefore, we conclude that the Cassiopia A and IC 443 SNRs are unlikely to be cosmic ray PeVatrons.

Memory editing: The role of temporal discontinuities in the compression of events in episodic memory editing.

Why does it take less time to remember an event than to experience it? Recent evidence suggests that the dynamic unfolding of events is temporally compressed in memory representations, but the exact nature of this compression mechanism remains unclear. The present study tested two possible mechanisms. First, it could be that memories compress the course of events into a sequence of moments or slices of prior experience, while omitting other segments, akin to edited films that give condensed accounts of events using sequences of separate shots (referred to as the discontinuity hypothesis). Alternatively, it may be that the entire stream of information is represented but is mentally replayed at a faster speed than the original experience (referred to as the acceleration hypothesis). In two experiments, these hypotheses were tested by comparing mental replay times for continuous movies depicting naturalistic events and edited versions of the same movies in which less informative parts were removed to mimic the presumed structure of memory representations according to the discontinuity hypothesis. We found that memories for videos in which less informative segments were replaced by temporal ellipses (Experiment 1) or by black screens of the same duration as removed segments (Experiment 2) were less compressed and contained a higher density of recalled units than did memories for complete videos. These results support the discontinuity hypothesis and suggest that segments of time that are redundant and predictable are omitted in episodic memory, while more informative segments are selectively retained to represent the unfolding of events. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Water cycle changes in reanalyses: a complementary framework

Climate reanalyses complement traditional surface-based measurements and offer unprecedented coverage over previously inaccessible or unmonitored regions. Even though these have improved the quantification of the global water cycle, their varying performances and uncertainties limit their applicability. Herein, we discuss how a framework encompassing precipitation, evaporation, their difference, and their sum could further constrain uncertainty by unveiling discrepancies otherwise overlooked. Ahead, we physically define precipitation plus evaporation to describe the global water cycle fluxes in four reanalysis data sets (20CR v3, ERA-20C, ERA5, and NCEP1). Among them, we observe four different responses to the temperature increase between 1950–2010, with ERA5 showing the best agreement with the water cycle acceleration hypothesis. Our results show that implementing the framework proposed can improve the evaluation of reanalyses’ performance and enhance our understanding of the water cycle changes on a global scale.

The bidirectional relationship between growth and appetite regulation in the first year of life

Abstract Childhood obesity is a public health crisis. Even though appetite traits in infancy were associated with childhood adiposity, whether early weight gain can influence later appetite has not been researched. Our aim was to prospectively examine the bidirectional association between growth and appetite traits during the first year of life. We followed up 450 healthy term infants for 12 months (m). Appetite traits at 4 weeks (wk), 6m and 12m were assessed using the Baby and Child Eating Behaviour Questionnaires. Infant feeding, anthropometric, socioeconomic and demographic data were also collected. Infant weight-for-age z-scores (WFAZ) were calculated using the WHO 2006 growth reference. Growth was assessed as conditional WFAZ change (cWFAZc) by saving the residuals from linear regression models of WFAZ at each successive time point versus WFAZ at the earlier time point. Multivariable linear regression was used to analyse bidirectional associations between cWFAZc (0-4wk, 4wk-6m, 6-12m) and appetite traits Enjoyment of Food (EF), Food Responsiveness (FR), Satiety Responsiveness (SR) and Slowness in Eating (SE) at 4wk, 6m and 12m. All models were adjusted for relevant confounders. At 4wk, SR score was associated with lower (β:-0.16; 95% CI:-0.28,-0.03), and FR score with higher (β:0.10; 95% CI:0.01,0.19) cWFAZc from 4wk to 12m. SR score at 6m was inversely associated with cWFAZc from 6-12m (β:-0.09; 95% CI:-0.16,-0.01). Conversely, higher cWFAZc between 4wk-6m was associated with higher EF (β:0.10; 95% CI:0.01,0.19) and FR (β:0.16; 95% CI:0.04,0.29) scores at 12m. cWFAZc between 6m-12m was inversely associated with SR at 12m (β:-0.18; 95% CI:-0.35,-0.01). Our results suggest that the growth acceleration hypothesis, where faster growth in infancy leads to later obesity, may be mediated by an up-regulation of appetite traits at 12m. This highlights the public health importance of avoiding growth acceleration in infancy as a way to curb the childhood obesity epidemic. Key messages • Weight gain in early infancy impacts appetite regulation in the first year of life and up-regulation of appetite traits at 12 months predisposes to childhood obesity. • Avoiding growth acceleration in infancy can decrease the risk for childhood obesity.

Identifying QAnon Conspiracy Theory Adherent Types

Since the 2016 election of President Donald Trump, conspiracy theories have become more salient among Americans. Using the deep state conspiracy theory QAnon as a case study, we argue three types of conspiracy theory adherents exist due to cognitive dissonance experienced in the face of key theory milestone failures: Hardliners, who do not face cognitive dissonance in response to failed conspiracy theory predictions; Moderates, committed members who experience cognitive dissonance and must adapt in order to maintain belief in the conspiracy theory, and Bandwagoners, casual members with shallow beliefs who experience cognitive dissonance and abandon the conspiracy theory. From these types, we put forth the bandwagoner acceleration hypothesis: by emphasizing the disconnect between complex deep state conspiracy theory beliefs and reality that demonstrates the falsehoods perpetrated by the movement, relevant stakeholders exogenous to the conspiracy theory can activate Bandwagoners to stimulate conspiratorial belief abandonment. This is important as Bandwagoners represent the peril of latent power which can be coopted and used to threaten democratic legitimacy.

The effect of propolis-xenograft on the expression of SOX2, SOX9, and woven bone in alveolar bone remodeling

Objective: This study was intended to analyze the expression of SRT-box transcription factor (SOX)2, SOX9 and woven bone in the preservation of tooth extraction sockets due to induction with propolis extract and bone graft. Materials and methods: 56 Cavia cobaya was divided into four groups according to the socket filling material used: control group, a propolis extract group, a bovine xenograft group, and a propolis extract-bovine xenograft group. An incisor tooth was extracted from each subject and the resulting socket filled with specific materials based on the group of which it was a member. After 3 days and 7 days, the Cavia cobaya were sacrificed in order to obtain their mandibles. Histopathological samples were made by means of hematoxylin-eosin and immunohistochemical staining under a light microscope at 400x magnification. Statistical analysis: The results were analyzed using one-way ANOVA. Results: A combination of propolis extract and bovine xenograft produced the highest expressions of SOX2, SOX9, and woven bone on day 3 and day 7, followed by the propolis group. The combination group experienced a significant difference with the control group on day 3 and day 7 (p&lt;0.001). Even though the combination group presented the highest expressions, the results of a Tukey HSD test indicated no significant difference between the propolis and combination groups on day 3 and day 7. Conclusion: A combination of propolis and bovine xenograft increased the expressions of SOX2, SOX9, and woven bone. Further research is required to validate the bone remodeling acceleration hypothesis with regards to propolis.

Does Social Media Accelerate Product Recalls? Evidence from the Pharmaceutical Industry

Social media has become a vital platform for voicing product-related experiences that may not only reveal product defects, but also impose pressure on firms to act more promptly than before. This study scrutinizes the rarely studied relationship between these voices and the speed of product recalls in the context of the pharmaceutical industry in which social media pharmacovigilance is becoming increasingly important for the detection of drug safety signals. Using Federal Drug Administration drug enforcement reports and social media data crawled from online forums and Twitter, we investigate whether social media can accelerate the product recall process in the context of drug recalls. Results based on discrete-time survival analyses suggest that more adverse drug reaction discussions on social media lead to a higher hazard rate of the drug being recalled and, thus, a shorter time to recall. To better understand the underlying mechanism, we propose the information effect, which captures how extracting information from social media helps detect more signals and mine signals faster to accelerate product recalls, and the publicity effect, which captures how firms and government agencies are pressured by public concerns to initiate speedy recalls. Estimation results from two mechanism tests support the existence of these conceptualized channels underlying the acceleration hypothesis of social media. This study offers new insights for firms and policymakers concerning the power of social media and its influence on product recalls.

Precise integration of bridge structure collision models under seismic effect

Numerical analysis of collision is an important aspect of bridge seismic research. This paper introduces precise integration to the numerical analysis of seismic collision. Firstly, the collision forces of four contact element models were expressed in a unified form, including linear spring model, Kelvin-Voigt model, Hertz model, and Jan-Hertz-Damp model, and then the precision integration formula was derived for solving the collision force. Next, a collision time search method was proposed under the linear acceleration hypothesis, and the seismic collision was divided into a collision phase and a non-collision phase. Different time steps were adopted for the two phases. This strategy was verified by comparing simulation results with the data of theoretical analysis and shaking table test. The results show that precision integration ensures the accuracy of numerical calculation for bridge structure collision under seismic action, and achieves a high calculation efficiency; the contact element model and model parameters should be selected reasonably to analyze seismic collision of bridges; the Jan-Hertz-Damp model of contact elements boasts the highest simulation accuracy among the commonly used models.

Does Credit Supply Accelerate Business Cycle Changes in Korea?: Some New Evidence by Incorporating Regime Changes

This work empirically investigates how commercial banks' aggregate credit supply is associated with business cycle over different regimes of the Korean economy. Linear empirical models employed in most of previous studies are subject to a potential missapecification problem because it is well known that both real GDP and credit supply reveal different dynamic properties over different regimes. This work finds that credit supply has asymmetric effect on business cycle for expansion and contraction phases when the Smooth Transition Autoregressive Vector Error Correction Model (or STAR-VECM) is employed. Our empirical findings are as follows. Firstly, we find that credit supply has procyclical effect on real GDP in all phases. Secondly, the procyclical effects are significantly intensified especially in contractionary phases which indicates asymmetry of its effect. In sum, this result supports 'Credit Acceleration Hypothesis' of Bernanke et al. (1999). Lastly, we further find that real GDP has asymmetric effects on banks' credit supply with countercyclical effect on expansionary regimes.

Experienced Aggression and Target-Perpetrated Deviance: Is the Relationship Linear or Non-linear?

When workers are treated badly, they often respond by behaving badly. Research has found, for instance, that the extent to which workers experience various forms of workplace aggression is positively related to the extent to which they engage in deviant behavior. We extend this research, which has largely focused on linear effects, by examining the acceleration hypothesis. According to the acceleration hypothesis, experienced aggression’s relationship with target-perpetrated deviance is relatively weak at low levels of experienced aggression; however, the relationship becomes gradually stronger at increasing levels of experienced aggression. We tested the acceleration hypothesis within two studies. Study 1 (N = 726) used a sample of English-speaking workers and assessed experienced aggression with a measure of interpersonal conflict; Study 2 (N = 183) used a sample of Chinese workers and assessed experienced aggression with a measure of abusive supervision. Because of these differences between Studies 1 and 2, we were able to examine the generalizability of the acceleration hypothesis across diverse work settings and across different forms of experienced aggression. We found support for the acceleration hypothesis within both samples. As a result, our findings call into question the assumption that the relationship between experienced workplace aggression and target-perpetrated deviance is purely linear.

Mechanics of the dicrotic notch: An acceleration hypothesis.

The dicrotic notch is a prominent and distinctive feature of the pressure waveform in the central arteries. It is universally used to demarcate the end of systole and the beginning of diastole in these arteries. Despite its importance clinically, no physical mechanism for the formation of the dicrotic notch has been demonstrated convincingly. We first explore a mechanism based on the reflection of a backward wavefront from the aortic valve at the time of closure. This hypothesis is rejected on the basis of experimental evidence from measurements made in dogs. A new hypothesis is presented involving the acceleration of the aortic valve apparatus at the time of valve closure. This hypothesis is supported by new calculations of the acceleration of the aortic valve apparatus during the cardiac cycle based on computed tomography scans in man.

From the particle pair production to the Hawking–Unruh radiation in the maximal acceleration hypothesis

Starting from a nonstandard approach to the Unruh effect, we present a description of the emission of radiation from a black hole that avoids quantization of scalar fields and Bogoliubov transformations, but assumes the existence of a maximal acceleration. In this framework, the description appears closer to the original heuristic Hawking’s point of view, with respect to the standard scenario.

Alternating gaze in multi-party storytelling

We present a single case study on gaze alternation in three-party storytelling. The study makes use of the XML method, a ‘combinatorial approach’ (Haugh and Musgrave, 2019) involving multi-modal CA transcription converted into the XML syntax. We approach gaze alternation via (i) the addressee-status hypothesis, (ii) the texturing hypothesis, and (iii) the acceleration hypothesis. Hypothesis (i) proposes that the storyteller alternatingly looks at the recipients not only when their addressee status is symmetrical but also when their addressee status is asymmetrical. Hypothesis (ii) predicts that gaze alternation ‘textures’ the telling by occurring when the storytelling progresses from one segment to another. Hypothesis (iii) states that gaze alternation accelerates toward Climax and decelerates in Post-completion sequences. The analyses support the hypotheses. They suggest that alternating gaze works against the danger of exclusion caused by the dyadic structure of conversation. It further partakes in story organization as it occurs at points of transition from one story section to another section. Finally, accelerated gaze alternation constitutes an indexical process drawing the recipients' attention to the immediate relevance of stance display (Stivers, 2008). We conclude that the three hypotheses warrant further investigation to determine their generalizability across speakers and speech situations.

Skill Premium and Technological Change

The paper tests the presence of skill premium and capital skill complementarity in the Indian Economy. Using NSSO data for skilled and unskilled workers measured on the basis of educational qualification, the study attempts to find factors that affect the movement in skill premium in the Indian labour market. Using two different definitions, the study finds that skill premium does not show a stagnant behaviour. This was due to factors specific to the Indian economy- a large reserve army of labourers and a weak relative absorptive capacity of different sectors. Firms prefer adopting techniques such as flexibility, outsourcing, de-unionisation and hiring contract workers for maintaining higher level of profits rather than adopting new technologies. On account of these factors, Skill Biased Technical Change (SBTC) and acceleration hypothesis could not be observed in the Indian Economy.

The Stress Acceleration Hypothesis of Nightmares.

Adverse childhood experiences can deleteriously affect future physical and mental health, increasing risk for many illnesses, including psychiatric problems, sleep disorders, and, according to the present hypothesis, idiopathic nightmares. Much like post-traumatic nightmares, which are triggered by trauma and lead to recurrent emotional dreaming about the trauma, idiopathic nightmares are hypothesized to originate in early adverse experiences that lead in later life to the expression of early memories and emotions in dream content. Accordingly, the objectives of this paper are to (1) review existing literature on sleep, dreaming and nightmares in relation to early adverse experiences, drawing upon both empirical studies of dreaming and nightmares and books and chapters by recognized nightmare experts and (2) propose a new approach to explaining nightmares that is based upon the Stress Acceleration Hypothesis of mental illness. The latter stipulates that susceptibility to mental illness is increased by adversity occurring during a developmentally sensitive window for emotional maturation—the infantile amnesia period—that ends around age 3½. Early adversity accelerates the neural and behavioral maturation of emotional systems governing the expression, learning, and extinction of fear memories and may afford short-term adaptive value. But it also engenders long-term dysfunctional consequences including an increased risk for nightmares. Two mechanisms are proposed: (1) disruption of infantile amnesia allows normally forgotten early childhood memories to influence later emotions, cognitions and behavior, including the common expression of threats in nightmares; (2) alterations of normal emotion regulation processes of both waking and sleep lead to increased fear sensitivity and less effective fear extinction. These changes influence an affect network previously hypothesized to regulate fear extinction during REM sleep, disruption of which leads to nightmares. This network consists of a fear circuit that includes amygdala, hippocampus, and medial prefrontal cortex and whose substantial overlap with the stress acceleration findings allows the latter to be incorporated into a wider, more developmentally coherent framework.

The Complexity of Biomechanics Causing Primary Blast-Induced Traumatic Brain Injury: A Review of Potential Mechanisms.

Primary blast-induced traumatic brain injury (bTBI) is a prevalent battlefield injury in recent conflicts, yet biomechanical mechanisms of bTBI remain unclear. Elucidating specific biomechanical mechanisms is essential to developing animal models for testing candidate therapies and for improving protective equipment. Three hypothetical mechanisms of primary bTBI have received the most attention. Because translational and rotational head accelerations are primary contributors to TBI from non-penetrating blunt force head trauma, the acceleration hypothesis suggests that blast-induced head accelerations may cause bTBI. The hypothesis of direct cranial transmission suggests that a pressure transient traverses the skull into the brain and directly injures brain tissue. The thoracic hypothesis of bTBI suggests that some combination of a pressure transient reaching the brain via the thorax and a vagally mediated reflex result in bTBI. These three mechanisms may not be mutually exclusive, and quantifying exposure thresholds (for blasts of a given duration) is essential for determining which mechanisms may be contributing for a level of blast exposure. Progress has been hindered by experimental designs, which do not effectively expose animal models to a single mechanism and by over-reliance on poorly validated computational models. The path forward should be predictive validation of computational models by quantitative confirmation with blast experiments in animal models, human cadavers, and biofidelic human surrogates over a range of relevant blast magnitudes and durations coupled with experimental designs, which isolate a single injury mechanism.

The right infant nutrition: do nutrition and growth matter in the 6 to 24 month period?

In the last decades several studies tested the hypothesis that at early developmental stages certain foods or nutrients, in specific amounts, fed during limited sensitive periods, may lead to clinical alterations that take place decades later ( early nutritional programming of long term health). In spite of suggestions from different early dietary habits, epidemiologic data show that episodes of rapid growth (growth acceleration hypothesis), whichever the dietary habits, are associated with later unfavorable health conditions and should be prevented. Early fast weight gain may be associated with increased likelihood of developing insulin resistance, dyslipidemic conditions, obesity, elevated blood pressure, and endothelial dysfunction. Accordingly, infant’s growth pattern may represent the interaction between genetic background and environment, inclusive of nutrition. The branch of science focusing on these aspects is known as epigenetics . Different studies have shown on the other hand a reduced growth in infants with specific disorders (milk allergy, HIV) even before the overt clinical symptoms of the disease. Within this context the nutritionist’s task is the prevention of deficiencies, but intervention strategies to prevent malnutrition should emphasize improvements in linear growth in the first 2-3 years of life rather than aim at gaining weight, to prevent the event of rapid early weight gain. The present constraints of the global economic crisis require cost/benefit analyses for all the interventions to optimize nutrition and growth in early years. Recent indications for complementary feeding indicate the beneficial effects of introducing earlier food items such as egg and fish, together with breastfeeding continuation through the first year, in reducing the later risk of immune allergic disorders and metabolic impairments. Proceedings of the 10 th International Workshop on Neonatology · Cagliari (Italy) · October 22 nd -25 th , 2014 · The last ten years, the next ten years in Neonatology Guest Editors: Vassilios Fanos, Michele Mussap, Gavino Faa, Apostolos Papageorgiou

FERTILITY INTENTIONS AND EARLY LIFE HEALTH STRESS AMONG WOMEN IN EIGHT INDIAN CITIES: TESTING THE REPRODUCTIVE ACCELERATION HYPOTHESIS.

In life history theory, early life adversity is associated with an accelerated reproductive tempo. In harsh and unpredictable conditions in developing societies fertility is generally higher and the reproductive tempo faster than in more secure environments. This paper examines whether differences in female anthropometry, particularly adult height, are associated with fertility intentions of women in urban environments in India. The study population consists of women aged 15-29 (N=4485) in slums and non-slums of eight Indian cities in the National Family Health Survey (NFHS) of 2005-2006. Adult height is taken as a proxy for early childhood health and nutritional condition. Fertility intentions are examined by using two variables: the desire to have a child or another child, and to have it relatively soon, as indicative of accelerated reproductive scheduling. Evidence supporting the acceleration hypothesis is found in two urban frames out of 26 examined in a two-staged multinomial logistic model. In three cases, the relationship between fertility intentions and height is the opposite than expected by the acceleration hypothesis: taller women have a higher predictive probability of desiring a(nother) child and/or narrower birth spacing. Potential explanations for the partly contradictory relationship between the childhood health indicator and fertility intentions are discussed.

SKILL BIAS IN AN ENDOGENOUS GROWTH MODEL: EVALUATING THE CASE FOR MARKET SIZE AND ACCELERATION EFFECTS

Skill-biased technical change occupied empirical economists for much of the 1990s. The empirical literature firmly established a positive correlation between technology indicators and demand shifts. In the minds of many, that has established a causal relationship. This leap of faith, however, is at odds with Hicks's conventional wisdom that endogenous technological change will be biased toward using cheap and abundant resources. In addition, if the rate of technical change is considered to be endogenous, the assumption of an exogenous bias toward skilled labor should at least be questioned. Two hypotheses explaining endogenous skill bias in technical change have been suggested in the theoretical literature: the acceleration effect and the market size effect. In this paper these are studied in a single endogenous-growth model to derive the sufficient and necessary conditions for both hypotheses. After confronting these conditions with the evidence, the paper concludes that it strongly favors the acceleration hypothesis.