Definitive Claims Research Articles

Potential Melting of Extrasolar Planets by Tidal Dissipation

Tidal heating on Io due to its finite eccentricity was predicted to drive surface volcanic activity, which was subsequently confirmed by the Voyager spacecraft. Although the volcanic activity in Io is more complex, in theory volcanism can be driven by runaway melting in which the tidal heating increases as the mantle thickness decreases. We show that this runaway melting mechanism is generic for a composite planetary body with liquid core and solid mantle, provided that (i) the mantle rigidity, μ, is comparable to the central pressure, i.e., μ/(ρ gR P) ≳ 0.1 for a body with density ρ, surface gravitational acceleration g, and radius R P; (ii) the surface is not molten; (iii) tides deposit sufficient energy; and (iv) the planet has nonzero eccentricity. We calculate the approximate liquid core radius as a function of μ/(ρ gR P), and find that more than 90% of the core will melt due to this runaway for μ/(ρ gR P) ≳ 1. From all currently confirmed exoplanets, we find that the terrestrial planets in the L 98-59 system are the most promising candidates for sustaining active volcanism. However, uncertainties regarding the quality factors and the details of tidal heating and cooling mechanisms prohibit definitive claims of volcanism on any of these planets. We generate synthetic transmission spectra of these planets assuming Venus-like atmospheric compositions with an additional 5%, 50%, and 98% SO2 component, which is a tracer of volcanic activity. We find a ≳3σ preference for a model with SO2 with 5–10 transits with JWST for L 98-59bcd.

Primordial stochastic gravitational wave backgrounds from a sharp feature in three-field inflation. Part I. The radiation era

The detection of a primordial stochastic gravitational wave background has the potential to reveal unprecedented insights into the early universe, and possibly into the dynamics of inflation. Generically, UV-complete inflationary models predict an abundance of light scalars, so any inflationary stochastic background may well be formed in a model with several interacting degrees of freedom. The stochastic backgrounds possible from two-field inflation have been well-studied in the literature, but it is unclear how similar they are to the possibilities from many-field inflation. In this work we study stochastic backgrounds from more-than-two field inflation for the first time, focusing on the scalar-induced background produced during the radiation era by a brief turn in three-field space. We find an analytic expression for the enhancement in the power spectrum as a function of the turn rate and the torsion, and show that unique signatures of three-field dynamics are possible in the primordial power spectrum and gravitational wave spectrum. We confirm our analytic results with a suite of numerical simulations and find good agreement in the shape and amplitude of the power spectra. We also comment on the detection prospects in LISA and other future detectors. We do not expect the moderately large growth of the inflationary perturbations necessary for detection to cause a breakdown of perturbation theory, but this must be verified on a case-by-case basis for specific microphysical models to make a definitive claim.

Abstract 075: Treatment Trends and Clinical Outcomes of Endovascular Therapy for Pediatric Unruptured Intracranial Aneurysms

Introduction Due to the relative rarity of unruptured intracranial aneurysms (UIA) in the pediatric population, evidence regarding treatment modalities and clinical outcomes remains limited. This study aims to characterize the utilization and clinical outcomes of endovascular therapy (EVT) and microsurgical clipping (MSC) for pediatric UIAs over a two‐decade interval using a large national registry. Methods Pediatric (< 18 years of age) UIA hospitalizations were identified in the National Inpatient Sample from 2002 to 2019. Temporal utilization and clinical outcomes were compared for treatment with EVT and MSC. Results Among 734 UIAs identified during the study period, 64.9% (n = 476) were treated with EVT. Utilization of EVT significantly increased during the study period from 54.3% (2002‐2004) to 78.6% (2017‐2019) (p = 0.002 by Cochrane‐Armitage test). Treatment with EVT did not differ as a function of increasing age, but was mostly highly utilized in the youngest age grouping [70.4% (0‐2 years), 64.0% (3‐12 years), 64.3% (13‐17 years); p = 0.578]. In comparison with those treated with MSC, pediatric patients treated with EVT demonstrated higher rates of favorable outcomes (discharge to home without services) (96.0% vs. 91.1%, p = 0.006), shorter durations of hospital stay (4.6 vs. 10.0 days, p < 0.001), and lower rates of ischemic or hemorrhagic procedural‐related complications (1% vs. 4%, p = 0.010). Conclusion A retrospective evaluation of nearly twenty years of population‐level data from the United States demonstrates increasing utilization of EVT for the treatment of pediatric UIAs with high rates of favorable outcomes and shorter hospital stays in comparison to those treated with microsurgery. However, limitations of available registry data (such as absence of radiographic parameters and aneurysm morphological characteristics) temper any definitive claims regarding treatment efficacy.

Exploring the paradox of Muslim advantage in undernutrition among under-5 children in India: a decomposition analysis

BackgroundWhile there is a substantial body of research on inequalities in child nutrition along the axes of gender and socioeconomic gradient, the socio-religious differences in health and nutrition outcomes remain grossly understudied. The handful of studies on the socio-religious differential in child health outcomes has found a Muslim advantage in chances of survival and nutritional status over Hindus despite their comparatively lower socioeconomic status, which undeniably warrants investigating the pathways through which this paradoxical Muslim advantage manifests.MethodsUsing data from the National Family Health Survey, 2015-16, we quantify the inter-group differentials in child undernutrition (stunting, wasting, and underweight) between Muslims and caste-disaggregated Hindus. We further decompose the gap to delineate its major contributory factors by employing Fairlie’s decomposition method.ResultsThe analysis revealed that, compared to the Hindus as an aggregated group, Muslims have a higher rate of stunting and lower rates of wasting and being underweight. However, the differences get altered when we disaggregate the Hindus into high and low castes. Muslims have a lower prevalence of all three measures of undernutrition than the low-caste Hindus and a higher prevalence of stunting and underweight than the high-caste Hindus, consistent with their levels of socioeconomic status. However, the prevalence of wasting among Muslim children is lower than among high-caste Hindus. This nutritional advantage is paradoxical because Muslims’ relatively poorer socioeconomic status compared to high-caste Hindus should have disadvantaged them. In the decomposition analysis, the Muslim advantage over the low-caste Hindus could only be partially attributed to the former’s better economic status and access to sanitation. Moreover, the poor performance of Muslim children compared to the high-caste Hindus in stunting and underweight could mainly be explained by the religious differentials in birth order, mother’s education, and wealth index. However, Muslim children’s comparatively better performance in wasting than the high-caste Hindus remained a puzzle.ConclusionThe Muslim advantage over high-caste Hindus in wasting and low-caste Hindus in all the indicators of undernutrition may have been rendered by certain ‘unobserved’ behavioural and cultural differences. However, further exploration is needed to make a definitive claim in this respect.

The First and Lowest Operation of Pain: C.S. Lewis and His Image of ‘God’s Megaphone’ for Human Suffering

C.S. Lewis’s metaphor of ‘God’s megaphone’, an image he employed to illustrate an idea about human suffering, appears at a certain stage of his argument in the central chapter (ch. 6) of his first work of popular theology, The Problem of Pain (1940). Among the numerous images invoked throughout his writings, none perhaps is more widely known than this. From the earliest book-length study of Lewis (1949) onward, numerous quotations, allusions, and discussions that include the image of the megaphone can be found in the literature on Lewis and elsewhere; in 1957 the Dutch translation of Lewis’s book was published under the title Gods megafoon. While it would take a comprehensive reception history of The Problem of Pain for any definitive claims to be possible, the history of the ‘megaphone’ as cited in the literature suggests that this image has dominated perceptions of the book’s overall argument. The present essay will attempt to show that this dominance is a fact, and argues that this dominance finds no support in Lewis’s original argument.

Challenging opacity, embracing fuzziness: Geographical thought and praxis in a post-truth age

Recent years have seen a resurgence of interest in critical approaches to mapping and quantification within geography. Such works have embraced the potential of these methods to advance the cause of social and spatial justice in an increasingly data-driven world. But as more geographers are turning to these approaches, it seems that conventional sources of social data are less and less able to capture emerging forms of social and spatial inequality, or are made unavailable to researchers interested in uncovering and challenging these inequalities. This therefore opens up the question of how geographers interested in mobilizing maps and data for critical purposes can even study or make definitive claims about phenomena or processes for which there are no reliable or available sources of data? Together, these issues point to the fundamental challenge of opacity to the future of geographical thought and praxis, and the necessity for critical geographers to not simply abandon these methods because of such challenges, but rather embrace this fuzziness in new and productive ways.

UNDERSTANDING THE BODO MOVEMENT: IDENTITY POLITICS AND THE RISE OF POLITICAL VIOLENCE

The Bodo movement refers to the socio-political mobilization that emerged in the late 20th century in Assam emphasizing the indigenous Bodo community’s aspiration and struggle for the recognition of unique identity, cultural heritage and territorial rights. With its desire to attain greater autonomy and self-determination the movement mobilized the Bodo people through various forms of protests including strikes, rallies and civil disobedience. This paper makes an attempt to analyse how a complex interplay of historical, economic and cultural factors have shaped the trajectory of the movement. Focusing on the exclusivist tendencies generated by the movement the paper makes a critical investigation of the serious implications when a particular ethnic group obsessively pursues its identity politics with definite territorial claim in a multiethnic and multi-cultural society. Territorial claim based on narrow ethnic lines driven by exclusivist tendencies and informed by militant politics renders the other minority communities in the particular living space in a position of grave disadvantage undermining their rights. The paper argues that attempts made by the Bodo leadership to create a homogenous Bodo-inhabited area by carrying out a string of indiscriminate attacks, and process of ethnic cleansing against the non-Bodos in a shared homeland that is characterized by ethnic diversity not only in terms of plurality but of shared geographical and cultural space, essentially problematized the idea of democratic living in a shared homeland

Proof of Concept of an ELF Magnetic Field Exposure System with Biphasic Magnetic Pulses: Effects on Human Dermal Fibroblast Proliferation

The aim of this work was to validate the usefulness of an Extremely Low Frequency (ELF) magnetic field exposure system with a magnetotherapy device of common use in clinical practice that generates Biphasic Magnetic Pulses (BMP), in order to study the effects of the BMP on the proliferation of Human Dermal Fibroblasts (HDF). In that regard, HDF were exposed 2h in the morning and 2h in the afternoon for 2 days to BMP of 1.41mT peak value at 5, 10, 25Hz continuous and 50Hz intermittent (2s on/ 1.5s off). MTT assay was performed to assess proliferation. The 10Hz BMP showed a significant decrease in proliferation of 6.6% (p = 0.001) with respect to controls, but no significant changes in proliferation were seen with the other BMP. In order to analyze whether these results could be related to the exposure protocol, a 50Hz power line intermittent signal (1s on/ 1s off) was generated and tested but exposure time was increased to 48h to cover the complete cells doubling time. A significant increase in proliferation of 9% (p < 0.001) was found in this case. The results validate the in vitro exposure system for its use with the BMP. Though the MTT proliferation assay alone is not enough to make definitive claims, the results might indicate that exposure time plays a key role in the outcome of the experiments. Therefore, special attention should be paid to the exposure time on in vitro protocols and how they relate to in vivo experiments and current treatments.

The Puzzle of Anaphoric Bare Nouns in Mandarin: A Counterpoint toIndex!

Jenks (2018) argues that Mandarin bare NPs cannot be classified as definites simpliciter. Adopting the distinction between weak- and strong-article definites in Schwarz 2009, he proposes that Mandarin makes a lexical distinction between the two types of definites: bare nouns are weak definites, demonstratives are strong definites. He further proposes that their distribution is regulated by a principle called Index!. In this article, we first point out some problems with the empirical generalizations presented in Jenks’s description of Mandarin and then sketch an alternative approach to the distinction between Mandarin demonstratives and bare nouns. We end with some comments about the kind of further empirical work that needs to be done before definitive claims can be made about the competition between demonstratives and other types of definites.

Kunst, keskkond ja keskkonnaliikumine Eestis 1960.–1980. aastatel / Art, Environment, and Environmentalism in Estonia in the 1960s–1980s

Kunst, keskkond ja keskkonnaliikumine Eestis 1960.–1980. aastatel / Art, Environment, and Environmentalism in Estonia in the 1960s–1980s

Empire and Catastrophe: Decolonization and Environmental Disaster in North Africa and Mediterranean France Since 1954

Empire and Catastrophe: Decolonization and Environmental Disaster in North Africa and Mediterranean France Since 1954

An Ongoing Womanist Buddhist Project: Reading between the Times

This article challenges the dominant Christian-centered approach to Black religious life by exploring contemporary Womanist Buddhist and Black Buddhist practice, writing, and thought alongside writings of early East Asian Buddhist nuns, noting similarities, differences, and the intersections among and between these written accounts. “Reading Between the Times” signals the ongoing nature of this project, and this particular paper draws heavily upon Kathryn Ann Tsai’s 1994 translation Lives of the Nuns: Biographies of Chinese Buddhist Nuns from the Fourth to Sixth Centuries along with several Womanist and/or Black Buddhist voices, such as Faith Adiele, Melanie Harris, bell hooks, Layli Maparyan, Carolyn Jones Medine, Alice Walker, reverend angel Kyodo williams, Jan Willis, and Pamela Ayo Yetunde. Rather than make definitive claims, this paper becomes curious with initial observations surrounding authorial voice, intersections of race/gender/class within a particular temporal space, “legitimacy” questions, and others—and, of course, invites more work in the future. Deploying an engaged Buddhist pedagogy to inform mindful scholarship, this paper reminds us that we have more commonalities than oppressive systems often admit or acknowledge, and it concludes with a call to action.

Madhavrao Sapre at the Advent of Writing

By placing itself strategically within the debates surrounding the first Hindi short story, its authenticity and its colonial context, this essay wants to understand the repercussions that any claim of “first-ness” has for literature in general and Hindi literary historiography in particular. The underlying assumption is that in claiming something as a “first”, one inaugurates a tension – an event – in history. Latent in such a claim is the suggestion that the event, the first short story in this case, actually inaugurates a kind of prose writing that is absolutely new and singular without any historical antecedents. Instead of making any historically definitive claims of its own, or vouching for one of the many contending Hindi short stories, this essay traces the gestures of historiography that circumscribe Madhavrao Sapre’s short story Ek Tokri Bhar Mitti, and announce its originality. The essay’s focus on the Hindi prose, especially short story, would be guided by the historiography of the form, the choice of narrative technique, thematic models, the register of Hindi used in the stories, and quite significantly, the place and motive of publication. Also relevant to the essay, as both a backdrop and a conceptual optic, is Derrida’s theorization of generic events – events that mark the beginning of a specific genre of writing and of the laws that give the genre its proper name. The proper name attributed to Sapre’s work, to the advent it marks, is kahaani or short story and, with Derrida, this essay will question the possibilities of both the advent and its attendant proper name.

Lucretia Mott Essay Award 2021, Honourable Mention

This paper investigates the tension between Rufus Jones’ Quaker mysticism and miracles recorded in early Quakerism. It uses George Fox’s Book of Miracles to establish early Quaker beliefs and compares these recorded beliefs with Jones’ writing concerning miracles and mysticism, arguing that Jones’ conception of miracles was distinct from Fox’s. Jones often refrained from definite claims regarding the nature of miracles, but he did not claim the miracles of early Quakerism. The paper provides context for understanding distinguishing features, according to Jones, between the miraculous and the mystical.

The Consequences of Conflating Trans-ness and Vulnerability

The Consequences of Conflating Trans-ness and Vulnerability

The interrater reliability of the novel Udby classification of Modic Changes: A first estimate

BackgroundModic change grading is heterogeneous, inconsistent, and lacks a single nomenclature across the published literature. A new method of Modic change classification has been established by Dr. Peter Udby which hopes to unify how Modic changes are classified while also adding grading of the cranial/caudal extent of the Modic change across the vertebral body from the respective endplate involved to best capture the clinically relevant information of Modic changes. MethodsTwenty magnetic resonance images of potential basivertebral nerve ablation candidates were independently reviewed by two board-certified and fellowship trained neuroradiologist and two board-certified and fellowship-trained interventional spine physiatrists for the presence and characterization of Modic changes using the newly described Udby classification. 100% agreement of all four reviewers of Modic change presence, Type, and Udby classification was required to be classified as agreement. There were 480 total data points each with 10 unique choices to compare across the four independent reviewers. ResultsThe kappa value of their agreement was 0.5899 (95% CI 0.4860–0.6939). ConclusionThis study, requiring unanimous agreement between 4 physicians in application of the Udby classification, demonstrated an interrater reliability score of 0.5899 (95% CI 0.4860–0.6939). While this figure provides a first estimate, larger scale research is necessary before definitive claims regarding the interrater agreement validity of the Udby characterization system may be made.

459 Association Between Vitamin D Deficiency and Surgical Site Infection Following Elective Lumbar Fusions

INTRODUCTION: Vitamin D deficiency has been associated with higher rates of SSI following a variety of surgical procedures. However, this association has been under-investigated for spinal procedures. METHODS: Patients who underwent lumbar fusions between 2011-2014 were reviewed from the HCUP-NIS database. Propensity score matching was utilized to minimize the effect of confounding variables between the 2 groups (normal vitamin D vs vitamin D deficiency). RESULTS: A total of 238,875 cases of lumbar fusions met inclusion criteria for analysis. These included posterior/transforaminal lateral interbody fusions (PLIF/TLIF), Anterior lumbar interbody fusion (ALIF) and lateral lumbar interbody fusion (LLIF). 22,454 (9.4%) patients carried the diagnosis of vitamin D deficiency and were significantly more likely to be non-white (26.5% vs. 19.9%) and obese (21.1% vs. 15.4%) as compared to patients without deficiency. Other patient characteristics, socioeconomic factors, and hospital setting were comparable between two groups. SSI rates were compared between matched cohorts (18,350 patients in each). In patients without vitamin D deficiency, there were 202 (1.1%) cases of SSI recorded, while there were 1266 (6.9%) cases of SSI recorded in patients with vitamin D deficiency (P&lt;0.001). Patients with vitamin D deficiency had higher incidence of thromboembolic events (2.6% vs. 0.3%), length of hospital stay (5.7 vs. 3.4 days) as well as increased hospital charges (87,812$ vs. 79,650), (P &lt;0.05). CONCLUSION: Optimizing preoperative vitamin D level could be potentially a cost-effective strategy to reduce the rate of SSI, thromboembolic events and prolonged hospital stay in patients undergoing lumbar fusion. Further cost-effectiveness analyses are encouraged to make definitive claims regarding pre-operative vitamin D screening/supplementation in these patients.

"Scary and Effective, Definitely Pushes Me to Quit Smoking": Developing Waterpipe Pictorial Health Warnings Targeting Young Adults in Lebanon.

Waterpipe (WP) smoking is the leading tobacco use method among young adults in Lebanon. WP use is harmful, yet misperceptions about its safety exist. Implementing pictorial health warning labels (HWLs) on WP products is a promising strategy to correct this misperception. This study aimed to culturally adapt a set of 12 pictorial HWLs recently developed by an international expert panel to young adults in Lebanon. HWLs were grouped into four themes: WP health risks, WP harm to others, WP-specific harms, and WP harm compared to cigarettes. We conducted nine focus groups among WP smokers and nonsmokers (N = 77; 52% females; age 18-34 years) to explore participants' perceptions of the developed HWLs on attention, reaction (fear, avoidance), effectiveness (harm perception), and improvement (design/content, relatedness). Sessions were audio-taped, transcribed verbatim, and analyzed using directed qualitative content analysis. Emotionally provocative warnings were perceived as most effective, while symbolic and abstract warnings were found not believable. Warnings depicting visible bodily health effects and harm to babies seemed most promising. Participants were generally skeptical about Theme 4 because it might encourage switching to cigarettes. For cultural adaptation, participants recommended using shorter text with affirmative phrases, increasing the picture's size and improving their quality, adding the WP device picture to enhance HWLs' relatability, and develop testimonial messages that depict real people and stories. Results will provide Lebanon and perhaps other countries in the Eastern Mediterranean Region with evidence-based HWLs that they can further develop, test, and implement within their specific culture. Results provide Lebanon with evidence-based WP-specific pictorial HWLs that can be further developed and tested. HWLs provoking negative affect, with visible health consequences, and depicting harm to babies are promising. Participants recommended using definitive scientific claims presenting the health risks in numerical form. However, this needs to be balanced against protecting the credibility of HWLs scientifically and legally. Increasing the HWLs size and adding the WP device picture to the HWLs can enhance their relatability. Further research can help address some questions raised by this study, such as the potential of testimonial warnings that depict real people.

Heterotopic Ossification Prophylaxis Following Operative Fixation of Acetabular Fractures: A Systematic Review.

Heterotopic ossification (HO) is a well-recognized complication following operative fixation of acetabular fractures with a range of severity and clinical consequences. The purpose of this review was to: (1) report the incidence of heterotopic ossification (HO) formation following operative fixation of acetabular fractures; (2) determine the effectiveness of prophylactic treatments for HO; and (3) assess the radiographic severity of HO with and without prophylactic treatment. A literature search for peer-reviewed articles was conducted utilizing a variety of research databases. PRISMA guidelines were followed and included in this review were full-length, English language manuscripts published before September 2019, using the following search criteria: "heterotopic ossification AND acetabulum OR acetabular." Studies that reported HO as one of the reported outcomes were included. Articles were excluded if radiographic HO was not reported and if it was evaluated in surgeries other than those involved in acetabular fractures. Extracted data included, but was not limited to: type of prophylaxis; incidence of HO; severity of HO based on the Brooker classification; and statistical significance. A methodologic quality appraisal of the included studies was also conducted. A total of 54 full-text studies with 5,890 patients with operatively fixed acetabular fractures met inclusion criteria. There were four level I studies, four level II study, 26 level III studies, and 20 level IV studies. The overall incidence of HO after acetabular fracture surgery was 28.4%. The rate of HO formation was: 34.9% without prophylaxis, 28.3% with non-steroidal anti-inflammatory drugs (NSAID) prophylaxis, and 21.2% with radiation therapy (RT). Patients receiving a combination of both RT and NSAIDs developed HO 21.8% of the time. The rate of radiographic severe HO was 13.9% (range, 0-75%) in patients without prophylaxis, 9.4% (range, 0-50%) with NSAID prophylaxis, 5.7% (range, 0-12.8%) with RT prophylaxis, and 11.7% (range, 0-18.5%) with the combination of RT and NSAIDs. With the current literature collected in this systematic review, there was a lower incidence and severity of heterotopic bone formation following acetabular fracture fixation using radiation prophylaxis compared to NSAIDs or no treatment. The available literature is heterogeneous in fracture characteristics, surgical approaches, and prophylactic regimens with a general lack of randomized control trials. Further prospective studies are required to make definitive claims on the optimal prophylactic strategy to prevent heterotopic ossification.

Different Training Durations and Frequencies of Tai Chi for Bone Mineral Density Improvement: A Systematic Review and Meta-Analysis.

Objective Tai Chi shows potential as a safe and cost-effective intervention to improve bone mineral density (BMD). However, the various effects caused by different training durations and frequencies have not been evaluated. This updated systematic review aims to explore the effectiveness of Tai Chi in attenuating bone mineral density loss based on different training durations and frequencies. Methods We conducted an extensive database search in Cochrane Central Register of Controlled Trials, PubMed, EMBASE, Web of Science, Chinese Biomedical Literature Database, China Knowledge Resource Integrated Database, Wanfang Data, and China Science and Technology Journal Database on randomized controlled trials that examined Tai Chi for BMD improvement. Two reviewers independently performed data screening and extraction. Study quality was evaluated using the Cochrane Handbook for Systematic Reviews of Interventions. Results A total of 23 randomized controlled trials involving 1582 patients were identified. The aggregated results have shown significant benefits in favor of Tai Chi on BMD improvement in the lumbar spine (SMD = 0.36, 95% [0.13, 0.59], P=0.002), femoral neck (SMD = 0.40, 95% [0.16, 0.63], P=0.0009), femoral trochanter (SMD = 0.43, 95% CI [0.20, 0.66], P=0.0002), and Ward's triangle (SMD = 0.31, 95% [0.15, 0.48], P=0.002). Such favorable benefits in Tai Chi can only be seen when compared with the nonexercise group, and Tai Chi showed no significant improvement in BMD change when compared with other exercises group. Subgroup analyses showed various effects of BMD improvement based on different training durations and frequencies of Tai Chi. Tai Chi is effective in attenuating BMD loss with an intervention frequency of >4 days/week in the lumbar spine, with an intervention frequency of >4 days/week or an intervention duration of >10 months in the femoral neck, and with an intervention duration of >10 months or a frequency of ≤4 days/week in Ward's triangle. Conclusions The results demonstrated that Tai Chi may have benefits in attenuating BMD loss. Different training durations and frequencies may result in variable effectiveness. Researchers should focus more on the training durations and frequencies of Tai Chi so that a more definitive claim can be made regarding the beneficial effects for BMD improvement.