bluuebunny/crossref_metadata_2025 huggingface dataset:
Can tweets be used to detect problems early with scientific papers? A case study of three retracted COVID-19/SARS-CoV-2 papers
Authors: Haunschild Robin , Bornmann Lutz
Published: April 2021

Methodological mistakes, data errors, and scientific misconduct are considered prevalent problems in science that are often difficult to detect. In this study, we explore the potential of using data from Twitter for discovering problems with publications. In this case study, we analyzed tweet texts of three retracted publications about COVID-19 (Coronavirus disease 2019)/SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) and their retraction notices. We did not find early warning signs in tweet texts regarding one publication, but we did find tweets that casted doubt on the validity of the two other publications shortly after their publication date. An extension of our current work might lead to an early warning system that makes the scientific community aware of problems with certain publications. Other sources, such as blogs or post-publication peer-review sites, could be included in such an early warning system. The methodology proposed in this case study should be validated using larger publication sets that also include a control group, i.e., publications that were not retracted.
From the Machete to the Microscope: Dennis Stevenson, Plant Morphologist
Authors: Rudall Paula J. , Specht Chelsea D.
Published: April 2021

To mark the commencement of Dennis Stevenson’s status as Senior Curator Emeritus at New York Botanical Garden, we present a brief and subjective overview of his academic achievements to date. We highlight his deep and scholarly background in plant morphology, his adherence to cladistic methodologies for testing hypotheses of organismal relationships, especially in cycads and monocots, and his inspirational influence on students and colleagues within the botanical community.
Side-to-side esophagogastric anastomosis for minimally invasive Ivor-Lewis esophagectomy: operative technique and short-term outcomes
Authors: Fabbi Manrica , De Pascale Stefano , Ascari Filippo , Petz Wanda Luisa , Fumagalli Romario Uberto
Published: April 2021

Totally minimally invasive Ivor-Lewis esophagectomy (TMIIL) is associated to lower rate of post-operative complication, decreases length of hospital stay and improves quality of life compared to open approach. Nevertheless, adaptation of TMIIL still proceeds at slow pace, mainly due to the difficulty to perform the intra-thoracic anastomosis and heterogeneity of surgical techniques. We present our experience with TMIIL utilizing a stapled side-to-side anastomosis. We retrospectively evaluated 36 patients who underwent a planned TMIIL from January 2017 to September 2020. Esophagogastric anastomoses were performed using a 3-cm linear-stapled side-to-side technique. General features, operative techniques, pathology data and short-term outcomes were analyzed. The median operative time was 365 min (ranging from 240 to 480 min) with a median blood loss of 100 ml (50–1000 ml). The median overall length of stay was 13 (7–64) days and in-hospital mortality rate was 2.8%. Two patients (5.6%) had an anastomotic leak, without need for operative intervention and another patient developed an anastomotic stricture, resolved with a single endoscopic dilation. Chylothorax occurred in three patients; two of these required a surgical intervention. Pulmonary complications occurred in six patients (16.7%). Based on Comprehensive Complications Index (CCI), median values of complications were 27.9 (ranging from 20.9 to 100). The results of our study suggest that TMIIL with a 3-cm linear-stapled anastomosis seems to be safe and effective, with low rates of post-operative anastomotic leak and stricture.
Generalized Hsiung–Minkowski formulae on manifolds with density
Authors: Abdelmalek Mohammed
Published: April 2021

In this work, using the weighted symmetric functions $$\sigma _{k}^{\infty }$$

σ

k

∞

and the weighted Newton transformations $$T_{k}^{\infty }$$

T

k

∞

introduced by Case (Alias et al. Proc Edinb Math Soc 46(02):465–488, 2003), we derive some generalized integral formulae for close hypersurfaces in weighted manifolds. We also give some examples and applications of these formulae.
Investigation on the performance and emissions profile of CI engine using cashew nut shell pyro oil–toluene–diesel blends
Authors: Venkatesan K.
Published: April 2021

This article examines the prospects of using toluene added cashew nut shell pyro oil–diesel blends as alternative fuels in CI engine. Effects of adding fixed proportion (by vol.) of toluene (TU) to various cashew nut shell pyro oil (CPO)–diesel (D) blends on the performance and exhaust emission characteristics of a direct injection, single cylinder, water cooled, naturally-aspirated, constant speed run, 4-stroke CI engine were investigated under varied brake power conditions. Tested fuels were neat diesel, CPOT5 (5% CPO + 5% TU + 90% D), CPOT10 (10% CPO + 5% TU + 85% D) and CPOT15 (15% CPO + 5% TU + 80% D). CPO was extracted through a lab-scale fast pyrolysis apparatus. Fuel samples were prepared and characterized according to ASTM standards. Owing to the features like low sensitivity, impressive anti pinging, etc., presence of toluene in an optimal CPO-diesel blend was expected to promote the engine characteristics. Set of experiments were conducted for each fuel mixture and the respective in-cylinder pressure, fuel consumption, exhaust emission levels, temperatures were recorded. At the rated power output condition, CPOT5 fuel had shown 1.67% increased brake thermal efficiency, 5% reduced brake specific fuel consumption, almost 3% reduced exhaust gas temperatures as well as reduced the exhaust emissions such as HC (from 91 to 87 ppm), CO (from 0.1 to 0.08%), NOx (from 458 to 426 ppm), smoke levels (from 72 to 69 BSN). CPOT5 showed improved combustion characteristics like reduced ignition delays and combustion durations, increased rates of cylinder pressure rise and heat release. However, overall attained improvements in the engine parameters were found to be not up to the mark which makes the chances of using CPOT5 as best alternative to diesel feeble.

Article highlights

The Cashew nut shells agro-waste is efficiently converted into an alternative fuel.

Effect of adding toluene to pyro oil – diesel blends in CI engine is examined.

Engine performance is improved marginally with 1.6% higher brake thermal efficiency (BTE) and 5% lower brake specific fuel consumption (BSFC).

Reductions in CO, HC, NOx and smoke emissions are observed.

Reduced Ignition delay and combustion durations, increased rate of pressure rise, and increased HRR are observed.
Conceptualising household food insecurity in Northern Ireland: risk factors, implications for society and the economy, and recommendations for business and policy response
Authors: Beacom Emma , Furey Sinéad , Hollywood Lynsey , Humphreys Paul
Published: April 2021

Household food insecurity in developed nations has been identified as a significant public health concern. Although various research on the topic exists, such as contributors to food insecurity, and implications for individual physical and mental health outcomes; there is currently a lack of consideration as to how individual implications of food insecurity such as poor physical and mental health can consequently impact on business and the wider economy. In addition, there is a lack of conceptual literature related to food insecurity. Stakeholder interviews (n = 19) were conducted, and data were used to inform the conceptual model (risk factors, potential implications for individuals, the economy and business, and opportunities for business and policy response). The main suggested implications related to business and the economy were reduced contribution to the workforce and the economy, and increased cost pressures on the National Health Service. Business responses suggested included the inclusion of initiatives to address food insecurity in corporate social responsibility strategies, and further involvement of food businesses/retailers in redistributing surplus food. Policy responses suggested included policies relating to welfare, wages and work contracts, food redistribution incentives, sustainability, and community interventions in disadvantaged areas. The resulting model is unique in conceptualising food insecurity in the Northern Ireland context, with applicability to the UK and other developed nations.
Semantics and the Ontology of Number
Authors: Snyder Eric
Published: April 2021

What are the meanings of number expressions, and what can they tell us about questions of central importance to the philosophy of mathematics, specifically 'Do numbers exist?' This Element attempts to shed light on this question by outlining a recent debate between substantivalists and adjectivalists regarding the semantic function of number words in numerical statements. After highlighting their motivations and challenges, I develop a comprehensive polymorphic semantics for number expressions. I argue that accounting for the numerous meanings and how they are related leads to a strengthened argument for realism, one which renders familiar forms of nominalism highly implausible.
The Monetary Gold Principle: A Matter of Submissions
Authors: d'Argent Pierre
Published: April 2021

In “The Monetary Gold Principle: Back to Basics,” Zachary Mollengarden and Noam Zamir claim that the well-known principle runs against fundamental ICJ statutory provisions. It would “depart” from Article 36(1), “undermine” Article 62, “import factors external” to Article 59 and “obscure . . . rather than illuminate . . . the relevant rules of law” contrary to Article 38(1). Additionally, the policy considerations upon which the principle is allegedly based—compliance, due process, and legitimacy—would support its abolition, rather than its perpetuation. I argue that the authors’ claims are unpersuasive in relation to Article 36(1) of the ICJ Statute (consent of the parties to adjudication) since they fail to distinguish between having jurisdiction in a case and exercising jurisdiction to decide a claim. The authors also overestimate the role of Article 62 in securing third-party interests, since only intervention as a party, rather than a non-party, is sufficient to overcome the Monetary Gold limitation.
Long Live Monetary Gold *Terms and Conditions Apply
Authors: Paparinskis Martins
Published: April 2021

Zachary Mollengarden and Noam Zamir want to take back to basics the principle associated with the Monetary Gold Removed from Rome in 1943 (Monetary Gold) judgment of the International Court of Justice (ICJ). Their “categorical” and mostly doctrinal claim, underpinned by policy concern about “the tensions between the bilateral presuppositions of the Statute and the increasingly multilateral nature of international affairs and international disputes” is “that the Monetary Gold principle is irreconcilable with the ICJ Statute's jurisdictional architecture.” The tension between bilateralism and community interests often provides an attractive analytical perspective, and points raised by the authors might be relevant in calibrating certain aspects of the principle. But its wholesale critique, while skillfully put, is ultimately unpersuasive. Careful consideration of basic instruments and issues is commendable but an exclusive focus that does not engage with the broader international legal process will miss its unmistakable and widespread endorsement of the Monetary Gold principle. Even the concern about the multilateral context ultimately counts against rather than in favor of their argument. Multilateral sensitivities can already be articulated within the four corners of Monetary Gold, and Mauritius/Maldives, delivered just as the ink was drying on the first draft of this essay, is a perfectly timed example for that.
Rules are Rules: Reconceiving Monetary Gold as a Rule of Procedure
Authors: McIntyre Juliette
Published: April 2021

The Case of the Monetary Gold Removed from Rome in 1943 is familiar to all international lawyers. Like a catechism, we are taught that the ICJ will not proceed with a case where the legal interests of a State not before the Court “would not only be affected by a decision, but would form the very subject-matter of the decision.” Mollengarden and Zamir's proposal that the Court should dispense with the Monetary Gold principle feels almost heretical. The authors contend that the ICJ Statute sets out a framework for balancing the interests of third parties through the use of the intervention procedure, and that Monetary Gold “disrupts that balance.” Monetary Gold is, they submit, to be treated as only a judicial decision, entitled under Article 36(1)(d) of the Statute to little deference as a source of legal principle. I suggest taking an altogether different approach. The best way to understand the place of the Monetary Gold principle is in the context of the ICJ's rule making powers pursuant to Article 30(1) of the Court's Statute. These rule making powers are not limited to the promulgation of formal Rules of Court but extend to the determination of appropriate procedures during the hearing of a case. These procedural rules (small r), articulated in the context of particular cases, may in time evolve into formal Rules of Court through an iterative process. Monetary Gold is an instance of the Court defining a small r procedural rule in a manner that is consistent with the Court's Statute.
Perceived Risk versus Empirically Founded Benefit of Masticating Gum
Authors: CHAKRABORTY Sweta
Published: April 2021

Despite robust evidence on the benefits of gum mastication as compared to its risks, places such as Singapore still outlaw chewing gum outside of medicinal purposes. Chewing gum has therapeutic and cognitive benefits such as reduced stress and increased attention, and its associated costs such as littering are disproportionately upheld and still prosecuted against in Singapore. This is a clear example of a policy implemented based on perception rather than cost–benefit analysis. Policies, even as minor as those related to gum mastication, must be entrenched in evidence, and any accompanying costs (eg littering) can and should be deterred through evidence-based communication efforts.
Risk factors and clinical outcomes associated with blood culture contamination
Authors: Klucher Justin M. , Davis Kevin , Lakkad Mrinmayee , Painter Jacob T. , Dare Ryan K.
Published: April 2021

Objective:

To determine patient-specific risk factors and clinical outcomes associated with contaminated blood cultures.

Design:

A single-center, retrospective case-control risk factor and clinical outcome analysis performed on inpatients with blood cultures collected in the emergency department, 2014–2018. Patients with contaminated blood cultures (cases) were compared to patients with negative blood cultures (controls).

Setting:

A 509-bed tertiary-care university hospital.

Methods:

Risk factors independently associated with blood-culture contamination were determined using multivariable logistic regression. The impacts of contamination on clinical outcomes were assessed using linear regression, logistic regression, and generalized linear model with γ log link.

Results:

Of 13,782 blood cultures, 1,504 (10.9%) true positives were excluded, leaving 1,012 (7.3%) cases and 11,266 (81.7%) controls. The following factors were independently associated with blood-culture contamination: increasing age (adjusted odds ratio [aOR], 1.01; 95% confidence interval [CI], 1.01–1.01), black race (aOR, 1.32; 95% CI, 1.15–1.51), increased body mass index (BMI; aOR, 1.01; 95% CI, 1.00–1.02), chronic obstructive pulmonary disease (aOR, 1.16; 95% CI, 1.02–1.33), paralysis (aOR 1.64; 95% CI, 1.26–2.14) and sepsis plus shock (aOR, 1.26; 95% CI, 1.07–1.49). After controlling for age, race, BMI, and sepsis, blood-culture contamination increased length of stay (LOS; β = 1.24 ± 0.24; P < .0001), length of antibiotic treatment (LOT; β = 1.01 ± 0.20; P < .001), hospital charges (β = 0.22 ± 0.03; P < .0001), acute kidney injury (AKI; aOR, 1.60; 95% CI, 1.40–1.83), echocardiogram orders (aOR, 1.51; 95% CI, 1.30–1.75) and in-hospital mortality (aOR, 1.69; 95% CI, 1.31–2.16).

Conclusions:

These unique risk factors identify high-risk individuals for blood-culture contamination. After controlling for confounders, contamination significantly increased LOS, LOT, hospital charges, AKI, echocardiograms, and in-hospital mortality.
Direct democracy, policy diffusion, and medicalized marijuana
Authors: Rugeley Cynthia , Frendreis John , Tatalovich Raymond
Published: April 2021

Abstract

Virtually all studies of policy diffusion are based on statutory enactments by state legislatures. But a substantial number of medicalized marijuana laws were initiated through citizen initiatives and ratified by referenda (I&R). This case study suggests that the diffusion of laws adopted by I&R requires two modifications to the conventional model of policy diffusion. First, early policy adoptions must occur through direct democracy so that horizontal diffusion results when those past adoptions by the I&R process lead to future adoptions. Second, the necessity of bypassing institutions of representative government must be operationalized as an interaction between the availability of direct democracy and the precise political variable that blocks legislative enactments.
How should wetheorizeabout justice in the genomic era?
Authors: Farrelly Colin
Published: April 2021

Abstract

The sequencing of the human genome and advances in gene therapy and genomic editing, coupled with embryo selection techniques and a potential gerontological intervention, are some examples of the rapid technological advances of the “genetic revolution.” This article addresses the methodological issue of how we should theorize about justice in the genomic era. Invoking the methodology ofnon-ideal theory, I argue that theorizing about justice in the genomic era entails theorizing about (1) the new inequalities that the genetic revolution could exacerbate (e.g., genetic discrimination, disability-related injustices, and gender inequality),and(2) those inequalities that the genetic revolution could help us mitigate (e.g., the risks of disease in early and late life). By doing so, normative theorists can ensure that we develop an account of justice that takes seriously not only individual rights, equality of opportunity, the cultural and sociopolitical aspects of disability, and equality between the sexes, but also the potential health benefits (to both individuals and populations) of attending to the evolutionary causes of morbidity and disability.
Frontiers and pioneers in (the study of) queer experiences in Africa Introduction
Authors: Spronk Rachel , Nyeck S. N.
Published: April 2021

This part issue of the journalAfricabroadly explores the idea of frontiers and pioneers in the study of queer African lives. We envisage frontiers as exploring new openings in the study of sexuality by putting forward the practices and experiences of people across the African continent. We propose to study queerness as part of broader quotidian realities so as to further theorize the study of sexualities and queerness. We propose the term ‘pioneer’ for the interlocutors in our studies: (self-identifying) women, men andqueeryingpersons who courageously explore contradictory paths in their various contexts. As such, we encourage an imaginative employment of queer as indicating a horizon of curiosity and imprecision. In making queerness not an object of study but rather a subject of its own theorization based on everyday experience, this special journal issue explicitly and deliberately asserts the vernacular and the mundane as a locus of knowledge. One implication is especially pertinent: knowledge on queerness cannot be prefabricated or preassembled in theoretical laboratories with the aim of merely applying it to an African context. By doing so, Africa functions – as it always has – only as a variable in the study of cultural difference, one that is different from, by implication, a Euro-American centre. ‘Or, as is happening too often, queer African voices and experiences will be absorbed as “data” or “evidence,” not as modes of theory or as challenges to the conceptual assumptions that drive queer studies’ (Macharia 2016: 185). Foregrounding the mundane rather than the urbane (as in ‘suave’, for which queer theory has a strong penchant), we are not trying to ‘define’ African queer sexualities; rather, we seek to provoke conversations about the terms and agencies of their expansion through the prism of frontiers and pioneers.
Love and homophobia in Malawi's spoken-word poetry movement
Authors: Englund Harri
Published: April 2021

By the early 2010s, a number of Malawian poets in their twenties had begun to substitute the elliptical expression of earlier generations with a language that resonated with popular idioms. As poetry directed at ‘the people’, its medium is spoken word rather than print, performed to live audiences and distributed through CDs, radio programmes and the internet. Crafted predominantly in Chichewa, the poems also address topics of popular interest. The selection of poetry presented here comes from a female and a male poet, who, unbeknown to each other, prepared poems sharply critical of homosexuality and what they regarded as its foreign and local advocacy. The same poets have also gained success for their love poems, which have depicted intimate desires in remarkably compatible ways for both women and men. The poets who performed ‘homophobic’ verse went against popular gender stereotypes in their depictions of romantic love and female and male desires. This introductory essay, as a contribution toAfrica's Local Intellectuals series, discusses the aesthetic challenges that the new poets have launched in the context of Malawi's modern poetry. With regard to gender relations in their love poems, the introduction also considers the poets’ possible countercultural contribution despite their avowed commitment to perform for ‘the people’.
Questioning territories and identities in the precolonial (nineteenth-century) Lake Kivu region
Authors: Mathys Gillian
Published: April 2021

Throughout Africa, contemporary boundaries are deemed ‘artificial’ because they were external impositions breaking apart supposedly homogeneous ethnic units. This article argues that the problem with the colonial borders was not only that they arbitrarily dissected African societies with European interests in mind, but also that they profoundly changed the way in which territoriality and authority functioned in this region, and therefore they affected identity. The presumption that territories could be constructed in which ‘culture’ and ‘political power’ neatly coincided was influenced by European ideas about space and identity, and privileged the perceptions and territorial claims of those ruling the most powerful centres in the nineteenth century. Thus, this article questions assumptions that continue to influence contemporary views of the Lake Kivu region. It shows that local understandings of the relationship between space and identity differed fundamentally from state-centred perspectives, whether in precolonial centralized states or colonial states.
Hloniphaand health: ancestors, taboos and social medicine in South Africa
Authors: Neely Abigail H.
Published: April 2021

This article examines the abandonment of an important food taboo – the prohibition of milk consumption by newly married women – in rural KwaZulu-Natal, South Africa in the 1940s and 1950s. Offering a detailed exploration of thishloniphacustom in three rural communities, I start from the position that food always reflects the entanglements of its material and symbolic attributes. By tracing health and illness, shifting livelihoods, diets and an important social medicine intervention, this article reveals that in the 1950s milk was a symbolically and materially different food than it had been in the 1930s. I argue that this difference determined whether or nothloniphawould be abandoned. By centring on understandings of food, health and taboos as material and symbolic, this article draws on scholarship on livestock in Southern Africa and contributes to scholarship on food taboos andhloniphacustoms, pushing for the incorporation of material aspects of those customs.
REVISITING THE RECTANGULAR CONSTANT IN BANACH SPACES
Authors: BARONTI M. , CASINI E. , PAPINI P. L.
Published: April 2021

Let X be a real Banach space. The rectangular constant
$\mu (X)$
and some generalisations of it,
$\mu _p(X)$
for
$p \geq 1$
, were introduced by Gastinel and Joly around half a century ago. In this paper we make precise some characterisations of inner product spaces by using
$\mu _p(X)$
, correcting some statements appearing in the literature, and extend to
$\mu _p(X)$
some characterisations of uniformly nonsquare spaces, known only for
$\mu (X)$
. We also give a characterisation of two-dimensional spaces with hexagonal norms. Finally, we indicate some new upper estimates concerning
$\mu (l_p)$
and
$\mu _p(l_p)$
.
The relationship between urinary polyphenol metabolites and dietary polyphenol intakes in young adults
Authors: Clarke Erin D. , Collins Clare E. , Rollo Megan E. , Kroon Paul A. , Philo Mark , Haslam Rebecca L.
Published: April 2021

Spot urinary polyphenols have potential as a biomarker of polyphenol-rich food intakes. The aim of this study is to explore the relationship between spot urinary polyphenols and polyphenol intakes from polyphenol-rich food sources. Young adults (18–24 years old) were recruited into a sub-study of an online intervention aimed at improving diet quality. Participants’ intake of polyphenols and polyphenol-rich foods was assessed at baseline and 3 months using repeated 24-h recalls. A spot urine sample was collected at each session, with samples analysed for polyphenol metabolites using LC-MS. To assess the strength of the relationship between urinary polyphenols and dietary polyphenols, Spearman correlations were used. Linear mixed models further evaluated the relationship between polyphenol intakes and urinary excretion. Total urinary polyphenols and hippuric acid (HA) demonstrated moderate correlation with total polyphenol intakes (rs = 0·29–0·47). HA and caffeic acid were moderately correlated with polyphenols from tea/coffee (rs = 0·26–0·46). Using linear mixed models, increases in intakes of total polyphenols or polyphenols from tea/coffee or oil resulted in a greater excretion of HA, whereas a negative relationship was observed between soya polyphenols and HA, suggesting that participants with higher intakes of soya polyphenols had a lower excretion of HA. Findings suggest that total urinary polyphenols may be a promising biomarker of total polyphenol intakes foods and drinks and that HA may be a biomarker of total polyphenol intakes and polyphenols from tea/coffee. Caffeic acid warrants further investigation as a potential biomarker of polyphenols from tea/coffee.
Weighting on waiting: Willpower and attribute weighting models of decision making
Authors: Harris Alison
Published: April 2021

Willpower is often conceptualized as incorporating effortful and momentary suppression of immediate but ultimately inferior rewards. Yet, growing evidence instead supports a process of attribute weighting, whereby normatively optimal choices arise from separable evaluation of different attributes (e.g., time and money). Strategic allocation of attention settles conflicts between competing choice-relevant attributes, which could be expanded to include self-referential predictions (“resolve”).
Stress and imagining future selves: resolve in the hot/cool framework
Authors: Metcalfe Janet , Jacobs William James
Published: April 2021

Although Ainslie dismisses the hot/cool framework as pertaining only to suppression, it actually also has interesting implications for resolve. Resolve focally involves access to our future selves. This access is a cool system function linked to episodic memory. Thus, factors negatively affecting the cool system, such as stress, are predicted to impact two seemingly unrelated capabilities: willpower and episodic memory.
Self-control (or willpower) seeks to bias the resolution of motivational conflicts toward an individual's long-term interests
Authors: Nordli Samuel A. , Hirt Edward R.
Published: April 2021

We define self-control as an individual's efforts to bias the outcome of present or anticipated motivational conflicts in order to increase the likelihood that subsequent behavior serves perceived long-term interests. We suggest suppression and resolve are not “mechanisms” that underlie self-control, but rather are classes of strategies that influence motivations in order to increase the likelihood of successful self-control outcomes.
Socializing willpower: Resolve from the outside in
Authors: Setman Stephen , Kelly Daniel
Published: April 2021

Ainslie's account of willpower is conspicuously individualistic. Because other people, social influence, and culture appear only peripherally, it risks overlooking what may be resolve's deeply social roots. We identify a general “outside-in” explanatory strategy suggested by a range of recent research into human cognitive evolution, and suggest how it might illuminate the origins and more social aspects of resolve.
Turán theorems for unavoidable patterns
Authors: GIRÃO ANTÓNIO , NARAYANAN BHARGAV
Published: April 2021

We prove Turán-type theorems for two related Ramsey problems raised by Bollobás and by Fox and Sudakov. First, for t ≥ 3, we show that any two-colouring of the complete graph on n vertices that is δ-far from being monochromatic contains an unavoidable t-colouring when δ ≫ n−1/t, where an unavoidable t-colouring is any two-colouring of a clique of order 2t in which one colour forms either a clique of order t or two disjoint cliques of order t. Next, for t ≥ 3, we show that any tournament on n vertices that is δ-far from being transitive contains an unavoidable t-tournament when δ ≫ n−1/[t/2], where an unavoidable t-tournament is the blow-up of a cyclic triangle obtained by replacing each vertex of the triangle by a transitive tournament of order t. Conditional on a well-known conjecture about bipartite Turán numbers, both our results are sharp up to implied constants and hence determine the order of magnitude of the corresponding off-diagonal Ramsey numbers.
Creating Public Opinion, Advancing Knowledge, Engaging in Politics: The Local Public Sphere in Chengdu, 1898–1921
Authors: Veg Sebastian
Published: April 2021

Situated far from coastal cities and foreign concessions, Chengdu yields insights into the role of the local press and its specific publics in the political evolution of the late Qing and early Republic. Despite its remote location, Chengdu developed its own modern press in the late Qing, relying on print entrepreneurs and modern journalists recruited from the ranks of the local literati and traditional sociability, in particular teahouses. They all played a role in forming a modern reading public which came to understand itself as a distinct local political community in dynamic interaction with national politics and transnational networks. The local press evinced three successive but intertwined ideals of publicness: as a link between the state and the people and a vector of enlightenment, as a professional forum for public opinion and as a tool for political mobilization. In solidifying public opinion around the local community, the press served as a forum and catalyst for political activism in the 1911 Railroad Protection movement and the 1919 May Fourth movement, events which were shaped as much by local dynamics as they were by national developments.
Climate resilience in rural Zambia: evaluating farmers’ response to El Niño-induced drought
Authors: Alfani Federica , Arslan Aslihan , McCarthy Nancy , Cavatassi Romina , Sitko Nicholas
Published: April 2021

This paper aims at identifying whether and how sustainable land management practices and livelihood diversification strategies have contributed to moderating the impacts of the El Niño-related drought in Zambia. This is done using a specifically designed survey called the El Niño Impact Assessment Survey, which is combined with the Rural Agricultural Livelihoods Surveys, as well as high resolution rainfall data at the ward level over 34 years. This unique panel data set allows us to control for the time-invariant unobserved heterogeneity to understand the impacts of shocks like El Niño, which are expected to become more frequent and severe as a result of climate change. We find that maize yields were substantially reduced and that household incomes were only partially protected from the shock thanks to diversification strategies. Mechanical erosion control measures and livestock diversification emerge as the only strategies that provided yield and income benefits under weather shock.
Economic analysis of organic cropping systems under different tillage intensities and crop rotations
Authors: Dayananda Buwani , Fernandez Myriam R. , Lokuruge Prabhath , Zentner Robert P. , Schellenberg Michael P.
Published: April 2021

Costs of production and organic price premiums are defining factors influencing the economic viability of organic crop production systems. Different agronomic practices, such as crop rotation and tillage intensity, are known to affect the economic performance of the production systems. The aim of this study was to compare the impact of two crop rotation sequences (simplified and diversified) and two levels of tillage intensity (high and low) on the cost of production, gross return and gross margin of crops when grown under organic management in the semi-arid Brown soil zone of the Canadian Prairies. The 2-year simplified rotation sequence consisted of forage pea (Pisum sativum L.) grown as a green manure followed by hard red spring wheat (HRSW) (Triticum aestivum L.), while the 4-year diversified rotation sequence was forage pea green manure followed by flax (Linum usitatissimum L.) or yellow mustard (Sinapis alba L.), field pea or lentil (Lens culinaris L.) and HRSW. Our hypothesis that a more diversified crop rotation would increase profitability over a traditional simplified crop rotation was supported by the findings. However, the findings did not support our hypothesis that reducing tillage intensity, and the combination of tillage reduction and diversified crop rotation through a synergetic response, would further enhance profitability. Analysis of the breakeven prices and breakeven yields for crops indicated the importance of adopting diversified crop rotations and choosing crops with high organic price premiums as means to maximize the long-term profitability of organic cropping systems.
Husten aus Sicht der Psychosomatischen Medizin
Authors: Olliges Elisabeth , Ronel Joram
Published: April 2021

Zusammenfassung. Im Folgenden streifen wir die psychosoziale Bedeutung des Symptoms Husten in der aktuellen Corona-Krise und beleuchten zudem eine historische Fallgeschichte, welche für die Entwicklung psychoanalytischer Theoriebildung eine Rolle gespielt hat. Im zweiten Teil dieses Aufsatzes fassen wir psychosomatische Konzepte zum Thema Husten zusammen, um sich den Bedeutungen dieses basalen Symptomes zu nähern.
Anthropogenic Warming and Population Growth May Double US Heat Stress by the Late 21st Century
Authors: Mukherjee Sourav , Mishra Ashok Kumar , Mann Michael E. , Raymond Colin
Published: April 2021

Globally, heat stress (HS) is nearly certain to increase rapidly over the coming decades, characterized by increased frequency, severity, and spatiotemporal extent of extreme temperature and humidity. While these characteristics have been investigated independently, a holistic analysis integrating them is potentially more informative. Using observations, climate projections from the CMIP5 model ensemble, and historical and future population estimates, we apply the IPCC risk framework to examine present and projected future potential impact (PI) of summer heat stress for the contiguous United States (CONUS) as a function of non‐stationary HS characteristics and population exposure. We find that the PI of short‐to‐medium duration (1–7 days) HS events is likely to increase more than three‐fold across densely populated regions of the U.S. including the Northeast, Southeast Piedmont, Midwest, and parts of the Desert Southwest by late this century (2060–2099) under the highest emissions scenario. The contribution from climate change alone more than doubles the impact in the coastal Pacific Northwest, central California, and the Great Lakes region, implying a substantial increase in HS risk without aggressive mitigation efforts.
Inland Tidal Oscillations Within the Yucatan Peninsula
Authors: Coutino Aaron , Stastna Marek , McNeill‐Jewer Chelsi , Reinhardt Eduard G.
Published: April 2021

The Yucatan Peninsula is composed of highly porous, karstified limestone, resulting in scarce surface water bodies. Portions of the peninsula have fracture zones throughout the subsurface. We present water level measurements from four inland locations, previously assumed to be hydrologically isolated from the regional aquifer, or at most leaky with a weak connection. At all locations, tidal oscillations were detected, and verified by performing significance testing. We argue that the presence of cave passages and fracture zones in the limestone allows for much further inland penetration of the tidal signal, compared to classical Richards equation based predictions. The analysis of lacustrine sediment‐based paleoclimate records from across the Yucatan Peninsula assumes low to no interchange between the water bodies and the aquifer, and this assumption may need to be revisited based on our results. Increased connectivity of aquifer to inland water bodies also suggests greater flood risk from sea level rise.
A Rocket‐Triggered Lightning Flash Containing Negative‐Positive‐Negative Current Polarity Reversal During Its Initial Stage
Authors: Li Fengquan , Sun Zhuling , Jiang Rubin , Tang Guoying , Liu Mingyuan , Li Xiao , Zhang Hongbo , Yuan Shanfeng , Tian Ye , Qie Xiushu
Published: April 2021

A rocket‐triggered lightning flash containing negative‐positive‐negative current polarity reversal during its initial stage is analyzed using multiple synchronized observation data. The flash was triggered under a thunderstorm transition zone between the convective region and the stratiform region. The upward positive leader branched and developed toward the stratiform region. When the negative initial continuous current was decreasing, a negative stepped leader was transformed from a recoil leader on a preexisting positive branch. As the negative leader developed toward the convective region, a breakdown process initiated on a preexisting positive channel and propagated toward the back end of the negative stepped leader, accompanied with a positive electric field change pulse. The current polarity changed from negative to positive about 0.22 ms after the onset of the breakdown process. The negative leader terminated after propagating for 71.08 ms, while scattered discharges on other positive branches maintained to develop, and then the ICC polarity changed from positive to negative.
Hot Air, Hot Lakes, or Both? Exploring Mid‐Holocene African Temperatures Using Proxy System Modeling
Authors: Dee Sylvia G. , Morrill Carrie , Kim Seung Hye , Russell James M.
Published: April 2021

Climate models predict Africa will warm by up to 5°C in the coming century, stressing African societies. To provide independent constraints on model predictions, this study compares two notable reconstructions of East African temperatures to those predicted by Paleoclimate Model Intercomparison Project (PMIP3) and transient TraCE (Transient Climate Evolution) simulations, focusing on the Mid‐Holocene (MH, 5–8 kyr B.P.). Reconstructions of tropical African temperature derived from lake sedimentary archives indicate 1–2.5°C of warming during the MH relative to the 20th century, but most climate models do not replicate the warming observed in these paleoclimate data. We investigate this discrepancy using a new lake proxy system model, with attention to the (potentially non‐stationary) relationship between lake temperature and air temperature. We find amplified lake surface temperature changes compared to air temperature during the MH due to heightened seasonality and precessional forcing. Lacustrine processes account for some of the warming, and highlight how the lake heat budget leads to a rectification of the seasonal cycle; however, the simulated lake heating bias is insufficient to reconcile the full discrepancy between the models and the proxy‐derived MH warming. We find further evidence of changes in mixing depth over time, potentially driven by changes in cloud cover and shortwave radiative fluxes penetrating the lake surface. This may confound interpretation for glycerol dialkyl glycerol tetraethers (GDGT) compounds which exist in the mixed layer, and suggests a need for independent constraints on mixed layer depth. This work provides a new interpretive framework for invaluable paleoclimate records of temperature changes over the African continent.
Significant Contribution of Severe Ozone Loss to the Siberian‐Arctic Surface Warming in Spring 2020
Authors: Xia Yan , Hu Yongyun , Huang Yi , Zhao Chuanfeng , Xie Fei , Yang Yikun
Published: April 2021

Severe ozone loss and significant surface warming anomalies in the Siberian Arctic were observed in spring 2020. Here, we show that the anomalous surface warming was likely related to the ozone loss. The dramatic Arctic ozone loss in March was shifted to Siberia in April and May, which largely cools the lower stratosphere and leads to an increase of high clouds by modifying the static stability in the upper troposphere. This further results in an increase of longwave radiation at surface which likely contributes to surface warming. Multiple linear regression demonstrates that ozone loss contributes most of the surface warming in April, while the Arctic Oscillation and ice‐albedo feedback play a minor role. In May, both ozone loss and ice‐albedo feedback contribute to the surface warming. These results support that surface warming in the Siberian Arctic could occur in April and May when severe ozone loss occurs in March.
Estimation of Water Surface Energy Partitioning With a Conceptual Atmospheric Boundary Layer Model
Authors: Liu Ziwei , Yang Hanbo
Published: April 2021

Open water surface evaporation (E) or the latent heat flux (λE) is of great importance to surface water and energy budget. However, partitioning of the available energy into sensible heat flux (H) and λE, quantified as the Bowen ratio (), is implicitly discrepant between models and observations. In this study, an explicit equation for the estimation of Bo (thus for the λE) is derived based on an atmospheric boundary layer model combined with the potential vapor pressure deficit budget. Derived equation only requires the air temperature (Ta) and specific humidity (Q) as inputs, and performs well in λE estimation with a relative error of <1% over observations of global sea and inland lake surfaces. More importantly, this equation clearly expresses the physical relationship between Bo and air temperature and humidity, thus revealing the mechanism of water surface energy partitioning in response to external environmental variables.
Chemical Gardens Under Mars Conditions: Imaging Chemical Garden Growth In Situ in an Environmental Scanning Electron Microscope
Authors: Sainz‐Díaz C. Ignacio , Escribano Bruno , Sánchez‐Almazo Isabel , Cartwright Julyan H. E.
Published: April 2021

We have performed and visualized chemical garden growth experiments directly in situ in an environmental scanning electron microscope. The microscope chamber simulates the surface of Mars. We demonstrate that chemical gardens can form under the conditions of temperature and pressure existing on Mars in the presence of liquid water, silicates, and metal salts. Using chemical gardens from aluminum salts, tubes were formed where the external surface is formed principally by silicate and the inner surface is predominantly aluminum oxide‐hydroxide. It should thus be expected that similar growths of metal salts may be found in geological explorations of water‐rich environments during the search for life on Mars.
A Foreshock Bubble Driven by an IMF Tangential Discontinuity: 3D Global Hybrid Simulation
Authors: Wang Chih‐Ping , Wang Xueyi , Liu Terry Z. , Lin Yu
Published: April 2021

Foreshock bubbles (FBs) have been observed upstream of solar wind tangential discontinuities (TDs). A hypothesized mechanism is that foreshock ions with gyroradii larger than the TD thickness may move to upstream side of TDs and generate FBs. In this study, we present the very first three‐dimensional global hybrid simulation of an FB driven by a TD. After the TD encounters the ion foreshock, plasma and magnetic field perturbations are generated upstream of the TD. These perturbations are characteristically consistent with the observed TD‐driven FBs, confirming that TDs can form FBs. We further analyze the initial perpendicular temperature increase initiating the FB and compare the temperature structure with that from tracing test‐particles in static TD electric and magnetic fields. The structure can be explained by the perpendicular velocity change of foreshock ions with large gyroradii as they encounter the magnetic field direction change across the TD, which supports the hypothesized mechanism.
Constraining Spectral Models of a Terrestrial Gamma‐Ray Flash From a Terrestrial Electron Beam Observation by the Atmosphere‐Space Interactions Monitor
Authors: Sarria D. , Østgaard N. , Kochkin P. , Lehtinen N. , Mezentsev A. , Marisaldi M. , Lindanger A. , Maiorana C. , Carlson B. E. , Neubert T. , Reglero V. , Ullaland K. , Yang S. , Genov G. , Qureshi B. H. , Budtz‐Jørgensen C. , Kuvvetli I. , Christiansen F. , Chanrion O. , Navarro‐González J. , Connel P. , Eyles C.
Published: April 2021

Terrestrial Gamma ray Flashes (TGFs) are short flashes of high energy photons, produced by thunderstorms. When interacting with the atmosphere, they produce relativistic electrons and positrons, and a part gets bounded to geomagnetic field lines and travels large distances in space. This phenomenon is called a Terrestrial Electron Beam (TEB). The Atmosphere‐Space Interactions Monitor (ASIM) mounted on‐board the International Space Station detected a new TEB event on March 24, 2019, originating from the tropical cyclone Johanina. Using ASIM's low energy detector, the TEB energy spectrum is resolved down to 50 keV. We provide a method to constrain the TGF source spectrum based on the detected TEB spectrum. Applied to this event, it shows that only fully developed Relativistic Runaway Electron Avalanche spectra are compatible with the observation. More specifically, assuming a TGF spectrum , the compatible models have ϵ ≥ 6.5 MeV (E is the photon energy and ϵ is the cut‐off energy). We could not exclude models with ϵ of 8 and 10 MeV.