bluuebunny/crossref_metadata_2025 huggingface dataset:
British Travellers and the Encounter with Britain, 1450-1700
Authors: Cramsie John
Published: May 2021

This book recovers the encounter with a 'multicultural' Britain by British travellers in the Tudor and Stuart periods. When William Camden, writing in the sixteenth century, set out to write the history of Britannia, he deliberately took to the roads to discover it first-hand, and those diverse cultures guided and informed his journeys. Here, John Cramsie offers original perspectives on Camden's multicultural Britain through the study of British travellers and their narratives. We meet characters such as the Tudor traveller John Leland, who intended to tell the peoples of England and Wales about themselves; chronicle how they came to settle the towns, villages, valleys, and mountaintops they called home; record the marks they left in the landscape; and celebrate the noble histories and cultures they created. Dozens - eventually hundreds - of Britons shared the same passion to meet their island neighbours and relate their experiences. The individuals studied in this book include actualas well as armchair travellers and those who blurred the boundaries between them. Their letters, diaries, journals, and histories range from the epic, poignant, and matter of fact to the exotic, preposterous, and hateful; the sources include actual and imaginative narratives and those which combined both elements. Travellers painted Britain with, in Leland's words, native colours that were rich, vibrant, and, above all, complex. Their remarkable journeys are the story of how Britons over two centuries met, interacted, and attempted (or not) to understand one another. Written with an eye to debates about immigration and ethnicity in today's Britain, the book emphasizes the long history of making and remaking the island's cultural mosaic. The encounter with Britain's native colours has beena burden of history and opportunity for millennia, not simply for our own times. JOHN CRAMSIE is Associate Professor, Department of History, Union College, NY.
Civilizing Thoreau
Authors: Schneider Richard J.
Published: May 2021

Recent book-length studies of Thoreau have focused either on his place in the history of the natural sciences or have applied political principles to his works. None, however, has fully addressed whatecocritic Rebecca Solnit calls "the Thoreau problem," the compartmentalizing of Thoreau's mind into either that of a hermit of nature or that of a champion of social reform. This book proposes an interdisciplinary solution to this problem through the connection between Thoreau's ecological study of nature and his intense interest in the emerging social sciences, especially the history of civilization and ethnology. The book first establishes Thoreau's "human ecology," the relation between the natural sciences and the social sciences in his thinking, exploring how his reading in contemporary books about the history of humanity and racial science shaped his thinking and connecting these emerging anthropological texts to his late nature writings. It then discusses these connections in his major works, including Walden and his "reform papers" such as "Civil Disobedience," the travel narrative A Week on the Concord and Merrimack Rivers, The Maine Woods, and Cape Cod. The concluding chapter focuses on Thoreau's attitude toward Manifest Destiny, arguing, against conventional views, that considering both his life and his writing, especially the essay "Walking," we must conclude that he both accepted and endorsed Manifest Destiny as an inevitable result of cultural succession. Richard J. Schneider is Professor Emeritus from Wartburg College.He has authored a monograph and many articles as well as edited three collections on Thoreau.
Any Port in a Pandemic: International Law and Restrictions on Maritime Traffic during the COVID-19 Pandemic
Authors: OKERMAN JUSTIN , VON TIGERSTROM BARBARA
Published: May 2021

The current international framework that purports to regulate the spread of communicable disease in the context of maritime traffic is a fragmented, internally inconsistent, and inadequately enforced patchwork of treaties (including the International Health Regulations (2005)) and customary international law. The COVID-19 pandemic has tested the current framework and revealed it to be inadequate to deal with a major global health emergency. States have imposed or failed to impose varying control measures, the effects of which have been witnessed on board passenger vessels around the world. The cruise industry, in particular, has a significant global economic impact; therefore, appropriate, enforceable international regulation is necessary to ensure the adequate control of future communicable disease outbreaks.
Spatial analysis for political scientists
Authors: Di Salvatore Jessica , Ruggeri Andrea
Published: May 2021

How does space matter in our analyses? How can we evaluate diffusion of phenomena or interdependence among units? How biased can our analysis be if we do not consider spatial relationships? All the above questions are critical theoretical and empirical issues for political scientists belonging to several subfields from Electoral Studies to Comparative Politics, and also for International Relations. In this special issue on methods, our paper introduces political scientists to conceptualizing interdependence between units and how to empirically model these interdependencies using spatial regression. First, the paper presents the building blocks of any feature of spatial data (points, polygons, and raster) and the task of georeferencing. Second, the paper discusses what a spatial matrix (W) is, its varieties and the assumptions we make when choosing one. Third, the paper introduces how to investigate spatial clustering through visualizations (e.g. maps) as well as statistical tests (e.g. Moran's index). Fourth and finally, the paper explains how to model spatial relationships that are of substantive interest to some of our research questions. We conclude by inviting researchers to carefully consider space in their analysis and to reflect on the need, or the lack thereof, to use spatial models.
Dietary patterns and sleep disorders in Mexican adults from a National Health and Nutrition Survey
Authors: Gaona-Pineda Elsa B. , Martinez-Tapia Brenda , Rodríguez-Ramírez Sonia , Guerrero-Zúñiga Selene , Perez-Padilla Rogelio , Shamah-Levy Teresa
Published: May 2021

Given the high prevalence of multiple non-communicable chronic diseases in Mexico, the aim of the present study was to assess the association between dietary patterns and sleep disorders in a national representative sample of 5076 Mexican adults (20–59 years) from the 2016 National Health and Nutrition Survey. Through a cross-sectional study, we used the Berlin sleep symptoms questionnaire to estimate the proportion of adults with insomnia, obstructive sleep apnoea (OSA) and other related problems such as daytime symptoms and inadequate sleep duration. Dietary data were collected through a seven-day semi-quantitative food frequency questionnaire, and dietary patterns were determined through cluster analysis. Associations between dietary patterns and sleep disorders were assessed by multivariate logistic regression models adjusted for age, sex, well-being, rural/urban area type, geographical region, tobacco use, physical activity level and energy intake. Three dietary patterns were identified: traditional (high in legumes and tortilla), industrialised (high in sugar-sweetened beverages, fast foods, and alcohol, coffee or tea) and mixed (high in meat, poultry, fruits and vegetables). Multivariate logistic regression showed that the industrialised pattern yielded higher odds for daytime symptoms (OR 1⋅49; 95 % CI 1⋅12, 1⋅99) and OSA (OR 1⋅63; 95 % CI 1⋅21, 2⋅19) compared with the traditional pattern. In conclusion, dietary patterns are associated with sleep disorders in Mexican adults. Further research is required to break the vicious cycle of poor-quality diet, sleep symptoms and health.
ON WEAKLY PERFECT ANNIHILATING-IDEAL GRAPHS
Authors: KADU GANESH S. , JOSHI VINAYAK , GONDE SAMRUDDHA
Published: May 2021

We prove that the annihilating-ideal graph of a commutative semigroup with unity is, in general, not weakly perfect. This settles the conjecture of DeMeyer and Schneider [‘The annihilating-ideal graph of commutative semigroups’, J. Algebra469 (2017), 402–420]. Further, we prove that the zero-divisor graphs of semigroups with respect to semiprime ideals are weakly perfect. This enables us to produce a large class of examples of weakly perfect zero-divisor graphs from a fixed semigroup by choosing different semiprime ideals.
‘Hong Kong can afford a typhoon or two’: British discussions of revolving storms
Authors: Huang Chi Chi
Published: May 2021

This article examines the way in which the British press reported on typhoons that affected Hong Kong during the nineteenth and early twentieth centuries. Typhoons were a significant element in the narration of the British Empire, featuring frequently in British accounts of their involvements in the Far East, where Hong Kong was its only colony. I suggest that these accounts need to be considered alongside the consolidation of the ‘tropics’ as a region in British perceptions, and in doing so, this article opens discussions of the study of tropicality to the consideration not just of climate, but also of the significance of singular weather events. This article argues that the cultural representations of typhoons in the British press were a tool of ‘othering’. In particular, there were two significant shifts around the 1880s in these reports. First, the term ‘typhoon’ became tied to these types of storms that affected Hong Kong. Second, the stories that were told about typhoon events emphasized British heroism and colonial management. Both these shifts in reporting stripped away the weather wisdom that British sailors had earlier identified in the local population.
SIMPLICITY CRITERIA FOR RINGS OF DIFFERENTIAL OPERATORS
Authors: BAVULA V. V.
Published: May 2021

Let K be a field of arbitrary characteristic,
$${\cal A}$$
be a commutative K-algebra which is a domain of essentially finite type (e.g., the algebra of functions on an irreducible affine algebraic variety),
$${a_r}$$
be its Jacobian ideal, and
$${\cal D}\left( {\cal A} \right)$$
be the algebra of differential operators on the algebra
$${\cal A}$$
. The aim of the paper is to give a simplicity criterion for the algebra
$${\cal D}\left( {\cal A} \right)$$
: the algebra
$${\cal D}\left( {\cal A} \right)$$
is simple iff
$${\cal D}\left( {\cal A} \right)a_r^i{\cal D}\left( {\cal A} \right) = {\cal D}\left( {\cal A} \right)$$
for all i ≥ 1 provided the field K is a perfect field. Furthermore, a simplicity criterion is given for the algebra
$${\cal D}\left( R \right)$$
of differential operators on an arbitrary commutative algebra R over an arbitrary field. This gives an answer to an old question to find a simplicity criterion for algebras of differential operators.
Grammaticalization and language contact in a discourse-pragmatic change in progress: The spread ofinnitin London English
Authors: Pichler Heike
Published: May 2021

This variationist analysis investigates the development and spread ofinnitas an invariant tag in London English. The sociolinguistic distribution ofinnitin a socially stratified corpus of vernacular speech suggests that the form's emergence and spread were initiated and propelled system-internally through changes associated with grammaticalization. Frequency triggered phonetic reduction ofisn't ittoinnit; loss of syntactic-semantic usage constraints and growing functional versatility enabledinnitto seize the range of contexts and functions of grammatically-dependent tags (e.g.didn't you,weren't we), virtually ousting these from the system of negative-polarity interrogative tags. Examination of cross-linguistic data and comparisons with relevant pre- and non-contact varieties indicate multiple language contact and grammatical replication may have played an ancillary role. I flag some challenges of establishing contact effects in discourse-pragmatic change, and propose that the promotion ofinnitfor invariant use was governed by its low salience and social indexicality of localness. (Innit, question tags, (Multicultural) London English, grammaticalization, language contact, grammatical replication)*
New frontiers in international retirement migration
Authors: King Russell , Cela Eralba , Fokkema Tineke
Published: May 2021

Introducing the special issue, this paper provides a state-of-the-art on established and new trends in the study of international retirement migration (IRM) and summarises the five papers that follow. Early studies on IRM were mainly within Europe and drew on the conceptual framework of lifestyle migration, with some reference to the transnational and mobilities paradigms. New frontiers in IRM are presented under three heads. Firstly, new geographical frontiers extend IRM to new destinations within and proximate to Europe, and to new locations in the global South such as Thailand and Ecuador. Secondly, new typological frontiers involve a broadening of the class and wealth backgrounds of the retirees, including the ‘return of retirement’ of labour migrants to their countries of origin, and attentiveness to IRM's gendered aspects. Thirdly, new conceptual and theoretical frontiers of IRM involve a more in-depth investigation of its transnational aspects, exploration of the various regimes of mobility and, most importantly, a political economy perspective which stresses global inequalities and histories of colonialism in shaping access to privileged lifestyles. In the final part of the paper, the original features of each paper in the special issue are highlighted, demonstrating how they are collectively integrated and contribute to the advancement of IRM research.
Depths in hooking networks
Authors: Desmarais Colin , Mahmoud Hosam
Published: May 2021

A hooking network is built by stringing together components randomly chosen from a set of building blocks (graphs with hooks). The vertices are endowed with “affinities” which dictate the attachment mechanism. We study the distance from the master hook to a node in the network chosen according to its affinity after many steps of growth. Such a distance is commonly called the depth of the chosen node. We present an exact average result and a rather general central limit theorem for the depth. The affinity model covers a wide range of attachment mechanisms, such as uniform attachment and preferential attachment, among others. Naturally, the limiting normal distribution is parametrized by the structure of the building blocks and their probabilities. We also take the point of view of a visitor uninformed about the affinity mechanism by which the network is built. To explore the network, such a visitor chooses the nodes uniformly at random. We show that the distance distribution under such a uniform choice is similar to the one under random choice according to affinities.
The Role of Volunteers in Enhancing Resident Quality of Life in Long-Term Care: Analyzing Policies that May Enable or Limit this Role
Authors: Hande Mary Jean , Taylor Deanne , Keefe Janice
Published: May 2021

Research has shown that long-term care (LTC) volunteers play important roles in enhancing the quality of life (QoL) of older LTC residents, often through providing unique forms of relational care. Guided by Kane’s QoL domains, we used a modified objective hermeneutics method to analyze how unique volunteer roles are represented and supported in provincial policies in Alberta, British Columbia, Ontario, and Nova Scotia. We found that policies define volunteer roles narrowly, which may limit residents’ QoL. This happens through (1) omitting volunteers from most regulatory policy, (2) likening volunteers to supplementary staff rather than to caregivers with unique roles, and (3) overemphasizing residents’ safety, security, and order. We offer insights into promising provincial policy directions for LTC volunteers, yet we argue that further regulating volunteers may be an inadequate or ill-suited approach to addressing the cultural, social, and structural changes required for volunteers to enhance LTC residents’ QoL effectively.
Crystal structure of the anticancer drug carmustine determined by X-ray powder diffraction
Authors: Schlesinger Carina , Alig Edith , Schmidt Martin U.
Published: May 2021

The structure of the anticancer drug carmustine (1,3-bis(2-chloroethyl)-1-nitrosourea, C5H9Cl2N3O2) was successfully determined from laboratory X-ray powder diffraction data recorded at 278 K and at 153 K. Carmustine crystallizes in the orthorhombic space groupP212121withZ= 4. The lattice parameters area= 19.6935(2) Å,b= 9.8338(14) Å,c= 4.63542(6) Å,V= 897.71(2) Å³ at 153 K, anda= 19.8522(2) Å,b= 9.8843(15) Å,c= 4.69793(6) Å,V= 921.85(2) Å³ at 278 K. The Rietveld fits are very good, with lowR-values and smooth difference curves of calculated and experimental powder data. The molecules form a one-dimensional hydrogen bond pattern. At room temperature, the investigated commercial sample of carmustine was amorphous.
Marital quality over the life course and child well-being from childhood to early adolescence
Authors: James Spencer L. , Nelson David A. , Jorgensen-Wells McKell A. , Calder Danielle
Published: May 2021

Research on marital quality and child well-being is currently limited by its common use of geographically constrained, homogenous, and often cross-sectional (or at least temporally limited) samples. We build upon previous work showing multiple trajectories of marital quality and data from the National Longitudinal Survey of Youth-1979 (NLSY79) regarding mothers and their children (inclusive of ages 5–14). We examine how indicators of child well-being are linked to parental trajectories of marital quality (happiness, communication, and conflict). Results showed children whose parents had consistently poor marital quality over the life course exhibited more internalizing and externalizing problems, poorer health, lower quality home environments, and lower math and vocabulary scores than children of parents in consistently higher-quality marriages. Group differences remained stable over time for child health, home environment, and vocabulary scores. Group differences for internalizing problems declined over time, whereas group differences increased for externalizing problems and math scores. Initial advantages for females across nearly all indicators of child well-being tended to shrink over time, with boys often moving slightly ahead by mid adolescence. We discuss the implications of these findings in regard to children's development and well-being and suggest treating marriage as a monolithic construct betrays important variation within marriage itself.
A ‘Sound Investment’? British Cultural Diplomacy and Overseas Students: The British Council's Students Committee, 1935–1939
Authors: Byrne Alice
Published: May 2021

This article explores the UK government's first foray into cultural diplomacy by focusing on the activities of the British Council's Students Committee in the run-up to the Second World War. Students were placed at the heart of British cultural diplomacy, which drew on foreign models as well as the experience of intra-empire exchanges. While employing cultural internationalist discourse, the drive to attract more overseas students to the United Kingdom was intended to bring economic and political advantages to the host country. The British Council pursued its policy in cooperation with non-state actors but ultimately was guided by the Foreign Office, which led it to target key strategic regions, principally in Europe and the Mediterranean Basin.
Pattern analysis of vegan eating reveals healthy and unhealthy patterns within the vegan diet
Authors: Gallagher Catherine T , Hanley Paul , Lane Katie E
Published: May 2021

Objective:

This study aimed to identify the types of foods that constitute a vegan diet and establish patterns within the diet. Dietary pattern analysis, a key instrument for exploring the correlation between health and disease, was used to identify patterns within the vegan diet.

Design:

A modified version of the EPIC-Norfolk FFQ was created and validated to include vegan foods and launched on social media.

Setting:

UK participants, recruited online.

Participants:

A convenience sample of 129 vegans voluntarily completed the FFQ. Collected data were converted to reflect weekly consumption to enable factor and cluster analyses.

Results:

Factor analysis identified four distinct dietary patterns including: (1) convenience (22 %); (2) health conscious (12 %); (3) unhealthy (9 %) and (4) traditional vegan (7 %). Whilst two healthy patterns were defined, the convenience pattern was the most identifiable pattern with a prominence of vegan convenience meals and snacks, vegan sweets and desserts, sauces, condiments and fats. Cluster analysis identified three clusters, cluster 1 ‘convenience’ (26·8 %), cluster 2 ‘traditional’ (22 %) and cluster 3 ‘health conscious’ (51·2 %). Clusters 1 and 2 consisted of an array of ultraprocessed vegan food items. Together, both clusters represent almost half of the participants and yielding similar results to the predominant dietary pattern, strengthens the factor analysis.

Conclusions:

These novel results highlight the need for further dietary pattern studies with full nutrition and blood metabolite analysis in larger samples of vegans to enhance and ratify these results.
A “K” to bridge Korea and the world: the state-led formulation of K-lit and its contradictions
Authors: Shim Bo-Seon
Published: May 2021

This study examines the activity of the Literature Translation Institute of Korea (LTI), a South Korean state agency promoting Korean literature internationally through translation. Analyzing LTI programs and participants in LTI policymaking and implementation, I advocate reconsideration of the conventional theorization of the state as either “strong” or “weak” in its control over national culture, corresponding to the degree of liberalization of market and politics. Instead, the institutional strength of the state and the marginal status – globally – of a given literature are intertwined and mutually transformative for the global formulation of a national literature. This study articulates how LTI's embeddedness in networks of domestic and international literary actors, such as translators, publishers, academics, and critics, both enables and constrains LTI policy. Based on the analysis, I argue that LTI as an intermediary formulates Korean literature with multiple components, combining the marketization of prominent writers with cultural consecration of non-commercial works, and universal literary values with nationalist cultural pride. Consequently, this study reveals the contentious nature of the state-led literary project, under which a national literature in global context is shaped collectively by actors both within and without the state.
Beneficial effects of oral supplementation with ferulic acid, a plant phenolic compound, on the human skin barrier in healthy men
Authors: Suzuki Atsushi , Nomura Tomoko , Jokura Hiroko , Kitamura Naoya , Fujii Akihiko , Hase Tadashi
Published: May 2021

Abstract. Ferulic acid (FA) is a phytochemical compound with various physiologic functions. To clarify the effect of FA intake on skin barrier function (SBF), we conducted a placebo-controlled double-blind pilot trial. Sixteen healthy subjects were divided into 2 groups (n = 8) and ingested capsules containing either FA (200 mg) or placebo daily for 2 weeks. Two measures of SBF, transepidermal water loss and stratum corneum hydration, were assessed before and 2 weeks after the start of the study. Autonomic nervous activity, which is suggested to be related to SBF, was also measured. Compared with the values obtained before the start of the study, FA intake significantly reduced transepidermal water loss (from 6.1 ± 1.1 to 4.8 ± 1.0 g/m2/h, p = 0.005) and increased stratum corneum hydration (from 30.1 ± 7.6 to 32.3 ± 8.1 a.u., p = 0.027) after 2 weeks. In addition, the amount change in sympathetic nervous activity was significantly reduced after ingesting the FA capsules compared with the placebo capsules (−0.7 ± 1.6 vs. 1.1 ± 1.4, p = 0.035). These findings suggest that FA supplementation decreases sympathetic nervous activity and strengthens SBF in healthy men.
Electrojet Estimates From Mesospheric Magnetic Field Measurements
Authors: Laundal K. M. , Yee J. H. , Merkin V. G. , Gjerloev J. W. , Vanhamäki H. , Reistad J. P. , Madelaire M. , Sorathia K. , Espy P. J.
Published: May 2021

The auroral electrojet is traditionally measured remotely with magnetometers on ground or in low Earth orbit (LEO). The sparse distribution of measurements, combined with a vertical distance of some 100 km to ground and typically >300 km to LEO satellites, means that smaller scale sizes can't be detected. Because of this, our understanding of the spatiotemporal characteristics of the electrojet is incomplete. Recent advances in measurement technology give hope of overcoming these limitations by multi‐point remote detections of the magnetic field in the mesosphere, very close to the electrojet. We present a prediction of the magnitude of these disturbances, inferred from the spatiotemporal characteristics of magnetic field‐aligned currents. We also discuss how Zeeman magnetic field sensors (Yee et al., 2021) onboard the Electrojet Zeeman Imaging Explorer satellites will be used to essentially image the equivalent current at unprecedented spatial resolution. The electrojet imaging is demonstrated by combining carefully simulated measurements with a spherical elementary current representation using a novel inversion scheme.
Impacts of Wind and Current on the Interannual Variation of the Summertime Upwelling Off Southern Vietnam in the South China Sea
Authors: Ngo Mai‐Han , Hsin Yi‐Chia
Published: May 2021

Summertime upwelling off the southern Vietnamese coast is one of the most essential oceanographic features in the South China Sea. Based on analyzing the 38‐year (1982–2019) sea surface temperature (SST) images, locations of summertime Vietnamese upwelling centers are found to be classified into three sub‐regions: the Southern Coastal Upwelling (SCU; south of 12.5°N), the Northern Coastal Upwelling (NCU; north of 12.5°N), and the Offshore Upwelling (OU; east of 110°E). Variations of upwelling intensities in the three sub‐regions are further quantified via an adaptive SST‐based upwelling index, and possible processes relevant to wind field (including wind stress and its curl) and currents are, respectively, proposed. The analyses show that the local along‐shore wind stress, inducing offshore Ekman transport, can produce the coastal upwelling‐favorable condition but is not the only one of main factors in controlling the interannual variability of the coastal upwelling. The enhancement of wind stress curl dipole off the southern Vietnamese coast, which accompanies the scaling up of the double‐gyre structure east of Vietnam and results in the reinforcement and southward shift of eastward‐flowing jet, and the exaggeration of the cyclonic gyre‐associated southward along‐shore current are responsible for the intensification of upwelling in the SCU, but suppress the development of upwelling in the NCU. The well‐developed double‐gyre structure serves as the essential condition for the OU occurrence and the OU is much more sensitive to the change of cyclonic gyre to the north of the jet.
The Impacts of Climate and Wildfire on Ecosystem Gross Primary Productivity in Alaska
Authors: Madani Nima , Parazoo Nicholas C. , Kimball John S. , Reichle Rolf H. , Chatterjee Abhishek , Watts Jennifer D. , Saatchi Sassan , Liu Zhihua , Endsley Arthur , Tagesson Torbern , Rogers Brendan M. , Xu Liang , Wang Jonathan A. , Magney Troy , Miller Charles E.
Published: May 2021

The increase in wildfire occurrence and severity seen over the past decades in the boreal and Arctic biomes is expected to continue in the future in response to rapid climate change in this region. Recent studies documented positive trends in gross primary productivity (GPP) for Arctic boreal biomes driven by warming, but it is unclear how GPP trends are affected by wildfires. Here, we used satellite vegetation observations and environmental data with a diagnostic GPP model to analyze recovery from large fires in Alaska over the period 2000–2019. We confirmed earlier findings that warmer‐than‐average years provide favorable climate conditions for vegetation growth, leading to a GPP increase of 1 Tg C yr−1, contributed mainly from enhanced productivity in the early growing season. However, higher temperatures increase the risk of wildfire occurrence leading to direct carbon loss over a period of 1–3 years. While mortality related to severe wildfires reduce ecosystem productivity, post‐fire productivity in moderately burned areas shows a significant positive trend. The rapid GPP recovery following fires reported here might be favorable for maintaining the region's net carbon sink, but wildfires can indirectly promote the release of long‐term stored carbon in the permafrost. With the projected increase in severity and frequency of wildfires in the future, we expect a reduction of GPP and therefore amplification of climate warming in this region.
Shifting Patterns of Summer Lake Color Phenology in Over 26,000 US Lakes
Authors: Topp Simon N. , Pavelsky Tamlin M. , Dugan Hilary A. , Yang Xiao , Gardner John , Ross Matthew R.V.
Published: May 2021

Lakes are often defined by seasonal cycles. The seasonal timing, or phenology, of many lake processes are changing in response to human activities. However, long‐term records exist for few lakes, and extrapolating patterns observed in these lakes to entire landscapes is exceedingly difficult using the limited number of available in situ observations. Limited landscape‐level observations mean we do not know how common shifts in lake phenology are at macroscales. Here, we use a new remote sensing data set, LimnoSat‐US, to analyze U.S. summer lake color phenology between 1984 and 2020 across more than 26,000 lakes. Our results show that summer lake color seasonality can be generalized into five distinct phenology groups that follow well‐known patterns of phytoplankton succession. The frequency with which lakes transition from one phenology group to another is tied to lake and landscape level characteristics. Lakes with high inflows and low variation in their seasonal surface area are generally more stable, while lakes in areas with high interannual variations in climate and catchment population density show less stability. Our results reveal previously unexamined spatiotemporal patterns in lake seasonality and demonstrate the utility of LimnoSat‐US, which, with over 22 million remote sensing observations of lakes, creates novel opportunities to examine changing lake ecosystems at a national scale.
Horton Index: Conceptual Framework for Exploring Multi‐Scale Links Between Catchment Water Balance and Vegetation Dynamics
Authors: Abeshu Guta Wakbulcho , Li Hong‐Yi
Published: May 2021

This paper is motivated to understand the multi‐temporal scale characteristics of Horton Index (HI), an indicator of catchment‐scale plant water use defined as the ratio of catchment vaporization (total evapotranspiration) to catchment wetting (precipitation minus surface runoff). Based on the generalized proportionality hypothesis, we first develop an analytical framework of HI applicable at multi‐temporal scales as a single function of ecological aridity index (EAI), defined as the ratio of potential evapotranspiration to catchment wetting. We successfully validate this framework at the long‐term, annual, and monthly scales at 343 natural catchments over the conterminous United States under varying climate and vegetation regimes. We show that vegetation plays an important role in regulating not only the partitioning of catchment wetting into vertical vaporization and horizontal baseflow, but also further partitioning of vaporization into initial and continuing components. Aided by this framework, we reveal emergent space‐time similarity patterns between HI’s spatial (inter‐catchment, regional) and temporal (within‐catchment, inter and intra‐annual) variability. On the one hand, HI increases with EAI, both spatially and temporally, following similar trends predicted by the analytical framework. On the other hand, the slopes of HI ∼ EAI relationships, denoted as d (HI)/d (EAI), decreased with EAI both spatially and temporally and, again, following similar trends suggested by the analytical framework. These findings suggest the promising potential of Horton Index as a conceptual yet quantitative framework for improving understanding and modeling of multi‐scale ecological and hydrological processes and their interactions.
Inference of Precipitation in Warm Stratiform Clouds Using Remotely Sensed Observations of the Cloud Top Droplet Size Distribution
Authors: Sinclair Kenneth , van Diedenhoven Bastiaan , Cairns Brian , Alexandrov Mikhail , Dzambo Andrew M. , L'Ecuyer Tristan
Published: May 2021

Drizzle is a common feature of warm stratiform clouds and it influences their radiative effects by modulating their physical properties and lifecycle. An important component of drizzle formation are processes that lead to a broadening of the droplet size distribution (DSD). Here, we examine observations of cloud and drizzle properties retrieved using colocated airborne measurements from the Research Scanning Polarimeter and the Third Generation Airborne Precipitation Radar. We observe a bimodal DSD as the aircraft transects drizzling open‐cells whereby the larger mode reaches a maximum size near cloud center and the smaller mode remains relatively constant in size. We review similarities between our observations with droplet growth processes and their connections with precipitation onset. We estimate droplet sedimentation using the cloud top DSD and find a correlation with rain water path of 0.82. We also examine how changes in liquid water paths and droplet concentrations may act to enhance or suppress precipitation.
Emergent Constraints on Regional Cloud Feedbacks
Authors: Lutsko Nicholas J. , Popp Max , Nazarian Robert H. , Albright Anna Lea
Published: May 2021

Low‐cloud based emergent constraints have the potential to substantially reduce uncertainty in Earth’s equilibrium climate sensitivity, but recent work has shown that previously developed constraints fail in the latest generation of climate models, suggesting that new approaches are needed. Here, we investigate the potential for emergent constraints to reduce uncertainty in regional cloud feedbacks, rather than the global‐mean cloud feedback. Strong relationships are found between the monthly and interannual variability of tropical clouds, and the tropical net cloud feedback. These relationships are combined with observations to substantially narrow the uncertainty in the tropical cloud feedback and demonstrate that the tropical cloud feedback is likely >0Wm−2K−1. Promising relationships are also found in the 90°–60°S and 30°–60°N regions, though these relationships are not robust across model generations and we have not identified the associated physical mechanisms.
Substrate control of sulphur utilisation and microbial stoichiometry in soil: Results of 13C, 15N, 14C, and 35S quad labelling
Authors: Ma Qingxu , Kuzyakov Yakov , Pan Wankun , Tang Sheng , Chadwick David R , Wen Yuan , Hill Paul W , Macdonald Andy , Ge Tida , Si Linlin , Wu Lianghuan , Jones Davey L
Published: May 2021

Global plant sulphur (S) deficiency is increasing because of a reduction in sulphate-based fertiliser application combined with continuous S withdrawal during harvest. Here, we applied 13C, 15N, 14C, and 35S quad labelling of the S-containing amino acids cysteine (Cys) and methionine (Met) to understand S cycling and microbial S transformations in the soil. The soil microorganisms absorbed the applied Cys and Met within minutes and released SO42− within hours. The SO42− was reutilised by the MB within days. The initial microbial utilisation and SO42− release were determined by amino acid structure. Met released 2.5-fold less SO42− than Cys. The microbial biomass retained comparatively more C and S from Met than Cys. The microorganisms decomposed Cys to pyruvate and H2S whereas they converted Met to α-ketobutyrate and S-CH3. The microbial stoichiometries of C, N, and S derived from Cys and Met were balanced after 4 d by Cys-derived SO42− uptake and Met-derived CO2 release. The microbial C:N:S ratio dynamics showed rapid C utilisation and loss, stable N levels, and S accumulation. Thus, short-term organic S utilisation by soil microorganisms is determined by amino acid structure whilst long-term organic S utilisation by soil microorganisms is determined by microbially controlled stoichiometry.
Serotonin-related rodent models of early-life exposure relevant for neurodevelopmental vulnerability to psychiatric disorders
Authors: Adjimann Tamara S. , Argañaraz Carla V. , Soiza-Reilly Mariano
Published: May 2021

Mental disorders including depression and anxiety are continuously rising their prevalence across the globe. Early-life experience of individuals emerges as a main risk factor contributing to the developmental vulnerability to psychiatric disorders. That is, perturbing environmental conditions during neurodevelopmental stages can have detrimental effects on adult mood and emotional responses. However, the possible maladaptive neural mechanisms contributing to such psychopathological phenomenon still remain poorly understood. In this review, we explore preclinical rodent models of developmental vulnerability to psychiatric disorders, focusing on the impact of early-life environmental perturbations on behavioral aspects relevant to stress-related and psychiatric disorders. We limit our analysis to well-established models in which alterations in the serotonin (5-HT) system appear to have a crucial role in the pathophysiological mechanisms. We analyze long-term behavioral outcomes produced by early-life exposures to stress and psychotropic drugs such as the selective 5-HT reuptake inhibitor (SSRI) antidepressants or the anticonvulsant valproic acid (VPA). We perform a comparative analysis, identifying differences and commonalities in the behavioral effects produced in these models. Furthermore, this review discusses recent advances on neurodevelopmental substrates engaged in these behavioral effects, emphasizing the possible existence of maladaptive mechanisms that could be shared by the different models.
CircRNAs: role in human diseases and potential use as biomarkers
Authors: Verduci Lorena , Tarcitano Emilio , Strano Sabrina , Yarden Yosef , Blandino Giovanni
Published: May 2021

Circular RNAs (circRNAs) are a class of endogenous RNAs characterized by a covalent loop structure. In comparison to other types of RNAs, the abundance of circRNAs is relatively low but due to the circular configuration, their stability is very high. In addition, circRNAs display high degree of tissue specificity. The sponging activity of circRNAs toward microRNAs is the best-described mode of action of circRNAs. However, the ability of circRNAs to bind with specific proteins, as well as to encode short proteins, propose alternative functions. This review introduces the biogenesis of circRNAs and summarizes the roles played by circRNAs in human diseases. These include examples of their functional roles in several organ-specific cancers, such as head and neck and breast and lung cancers. In addition, we review potential functions of circRNAs in diabetes, cardiovascular, and neurodegenerative diseases. Recently, a growing number of studies have demonstrated involvement of circRNAs in a wide spectrum of signaling molecular pathways, but at the same time many different and controversial views on circRNAs role and function are emerging. We conclude by offering cellular homeostasis generated by networks comprising circular RNAs, other non-coding RNAs and RNA-binding proteins. Accordingly, it is predictable that circRNAs, due to their highly stable nature and remarkable tissue specificity, will emerge as reliable biomarkers of disease course and treatment efficacy.
Viral dosing of influenza A infection reveals involvement of RIPK3 and FADD, but not MLKL
Authors: Oltean Teodora , Van San Emily , Divert Tatyana , Vanden Berghe Tom , Saelens Xavier , Maelfait Jonathan , Takahashi Nozomi , Vandenabeele Peter
Published: May 2021

RIPK3 was reported to play an important role in the protection against influenza A virus (IAV) in vivo. Here we show that the requirement of RIPK3 for protection against IAV infection in vivo is only apparent within a limited dose range of IAV challenge. We found that this protective outcome is independent from RIPK3 kinase activity and from MLKL. This shows that platform function of RIPK3 rather than its kinase activity is required for protection, suggesting that a RIPK3 function independent of necroptosis is implicated. In line with this finding, we show that FADD-dependent apoptosis has a crucial additional effect in protection against IAV infection. Altogether, we show that RIPK3 contributes to protection against IAV in a narrow challenge dose range by a mechanism that is independent of its kinase activity and its capacity to induce necroptosis.
CircRNA_2646 functions as a ceRNA to promote progression of esophageal squamous cell carcinoma via inhibiting miR-124/PLP2 signaling pathway
Authors: Zeng Bo , Liu Zhenguo , Zhu Haoshuai , Zhang Xin , Yang Weixiong , Li Xiaoxing , Cheng Chao
Published: May 2021

MicroRNA-124 (miR-124) has been predicted as a tumor suppressor in esophageal squamous cell carcinoma (ESCC). However, factors contributing to miR-124 reduction remain unclear. Circular RNAs (circRNAs) are a new family of non-coding RNAs with gene regulatory potential via interacting with miRNAs. We predicted three circRNAs, including CircRNA_14359, CircRNA_2646, and CircRNA_129, that could interact with miR-124 by bioinformatics analysis and determined their expressions in ESCC tissues and adjacent normal tissues. We found that CircRNA_2646 was up-regulated in ESCC, negatively correlated with the expression of miR-124 and positively associated with TNM stage and lymph node metastasis of ESCC. Luciferase reporter assay showed that CircRNA_2646 interacted with miR-124 in ESCC Eca109 and TE-1 cells. Moreover, ectopical overexpression of CircRNA_2646 accelerated cell proliferation, migration, invasion, and epithelial-to-mesenchymal transition (EMT), but restoration of miR-124 abrogated these functions and promoted Bcl-2-dependent cell apoptosis. Furthermore, it was found that the oncogene Proteolipid Protein 2 (PLP2) was the target gene of miR-124. In Eca109 and TE-1 cells, restoration of miR-124 decreased the level of PLP2 and inhibited PLP2-induced cell proliferation, migration, invasion, and EMT, but enhanced cell apoptosis. The in vivo study confirmed that CircRNA_2646 promoted ESCC development by repressing miR-124 and activating PLP2. Taken together, we identified that CircRNA_2646 functioned as an inhibitor in miR-124 signaling pathway in ESCC for carcinogenesis and could be a promising target for ESCC therapy.
Experimental evidence for hydrogen incorporation into Earth’s core
Authors: Tagawa Shoh , Sakamoto Naoya , Hirose Kei , Yokoo Shunpei , Hernlund John , Ohishi Yasuo , Yurimoto Hisayoshi
Published: May 2021

Hydrogen is one of the possible alloying elements in the Earth’s core, but its siderophile (iron-loving) nature is debated. Here we experimentally examined the partitioning of hydrogen between molten iron and silicate melt at 30–60 gigapascals and 3100–4600 kelvin. We find that hydrogen has a metal/silicate partition coefficient DH ≥ 29 and is therefore strongly siderophile at conditions of core formation. Unless water was delivered only in the final stage of accretion, core formation scenarios suggest that 0.3–0.6 wt% H was incorporated into the core, leaving a relatively small residual H2O concentration in silicates. This amount of H explains 30–60% of the density deficit and sound velocity excess of the outer core relative to pure iron. Our results also suggest that hydrogen may be an important constituent in the metallic cores of any terrestrial planet or moon having a mass in excess of ~10% of the Earth.
Power of data in quantum machine learning
Authors: Huang Hsin-Yuan , Broughton Michael , Mohseni Masoud , Babbush Ryan , Boixo Sergio , Neven Hartmut , McClean Jarrod R.
Published: May 2021

The use of quantum computing for machine learning is among the most exciting prospective applications of quantum technologies. However, machine learning tasks where data is provided can be considerably different than commonly studied computational tasks. In this work, we show that some problems that are classically hard to compute can be easily predicted by classical machines learning from data. Using rigorous prediction error bounds as a foundation, we develop a methodology for assessing potential quantum advantage in learning tasks. The bounds are tight asymptotically and empirically predictive for a wide range of learning models. These constructions explain numerical results showing that with the help of data, classical machine learning models can be competitive with quantum models even if they are tailored to quantum problems. We then propose a projected quantum model that provides a simple and rigorous quantum speed-up for a learning problem in the fault-tolerant regime. For near-term implementations, we demonstrate a significant prediction advantage over some classical models on engineered data sets designed to demonstrate a maximal quantum advantage in one of the largest numerical tests for gate-based quantum machine learning to date, up to 30 qubits.
A cortico-collicular pathway for motor planning in a memory-dependent perceptual decision task
Authors: Duan Chunyu A. , Pan Yuxin , Ma Guofen , Zhou Taotao , Zhang Siyu , Xu Ning-long
Published: May 2021

Survival in a dynamic environment requires animals to plan future actions based on past sensory evidence, known as motor planning. However, the neuronal circuits underlying this crucial brain function remain elusive. Here, we employ projection-specific imaging and perturbation methods to investigate the direct pathway linking two key nodes in the motor planning network, the secondary motor cortex (M2) and the midbrain superior colliculus (SC), in mice performing a memory-dependent perceptual decision task. We find dynamic coding of choice information in SC-projecting M2 neurons during motor planning and execution, and disruption of this information by inhibiting M2 terminals in SC selectively impaired decision maintenance. Furthermore, we show that while both excitatory and inhibitory SC neurons receive synaptic inputs from M2, these SC subpopulations display differential temporal patterns in choice coding during behavior. Our results reveal the dynamic recruitment of the premotor-collicular pathway as a circuit mechanism for motor planning.
Linking functional traits and demography to model species-rich communities
Authors: Chalmandrier Loïc , Hartig Florian , Laughlin Daniel C. , Lischke Heike , Pichler Maximilian , Stouffer Daniel B. , Pellissier Loïc
Published: May 2021

It has long been anticipated that relating functional traits to species demography would be a cornerstone for achieving large-scale predictability of ecological systems. If such a relationship existed, species demography could be modeled only by measuring functional traits, transforming our ability to predict states and dynamics of species-rich communities with process-based community models. Here, we introduce a new method that links empirical functional traits with the demographic parameters of a process-based model by calibrating a transfer function through inverse modeling. As a case study, we parameterize a modified Lotka–Volterra model of a high-diversity mountain grassland with static plant community and functional trait data only. The calibrated trait–demography relationships are amenable to ecological interpretation, and lead to species abundances that fit well to the observed community structure. We conclude that our new method offers a general solution to bridge the divide between trait data and process-based models in species-rich ecosystems.