bluuebunny/crossref_metadata_2025 huggingface dataset:
Orthorexia Nervosa: over concern or obsession about healthy food?
Authors: Novara Caterina , Pardini Susanna , Maggio Eleonora , Mattioli Sofia , Piasentin Sara
Published: February 2021

Purpose

Orthorexia Nervosa is characterized by specific behaviors frequently related to other psychopathological conditions, such as Obsessive–Compulsive Disorder (OCD) and Eating Disorders (EDs). Whereas ON can mainly be described as an excessive concern regarding healthy food, the study’s principal aim was to investigate if ON could be considered a condition related and differentiated from worry, other than OCD, EDs, perfectionism, anxiety, and depression.

Method

To achieve these aims, 302 individuals from the general population were enrolled and were divided into two groups named “High EHQ” and “Low EHQ”, based on their Eating Habits Questionnaire’s score (EHQ-21).

Results

Correlations of ON with EDs and non-adaptive perfectionism constructs emerged independently from Obsessive-Compulsive (OC) symptoms, and the same pattern was observed when comparing the High and the Low EHQ groups. The two groups also differ in the worry anxiety and depression constructs and are not affected by OC symptoms removal.

Discussion

Our results confirm a relationship between ON with the typical ED, perfectionistic, anxious, and depressive symptomatology, mainly when the OC features are controlled; moreover, worry constructs could be considered characteristic of the ON phenomenology. This study does not entirely exclude the relationship with obsessive and compulsive characteristics, which could be associated with or serve as a mediator of the orthorexic behavior. Future research could explore the potential mediating or collateral role of OC symptoms.

Level of evidence

Level III, evidence obtained from well-designed cohort or case–control analytic studies.
Sarcopenia, immune-mediated rheumatic diseases, and nutritional interventions
Authors: Cruz-Jentoft Alfonso J. , Romero-Yuste Susana , Chamizo Carmona Eugenio , Nolla Joan M.
Published: February 2021

Introduction

Sarcopenia is defined by a loss of muscle mass and function associated with mortality, decreased physical performance, falls, and disability. Since chronic inflammation and decreased physical activity are risk factors for developing sarcopenia, it is critical to assess the role of sarcopenia in immune-mediated rheumatic diseases (IMRDs). Moreover, nutritional interventions are emerging as key modifiable and affordable options to improve physical performance in sarcopenia.

Objective

The aim of this review is to critically summarize current information on the evidence linking nutritional interventions and sarcopenia in IMRDs.

Methods

The search and selection of articles was performed in Medline, Dimensions.ai, Google Scholar, Cochrane Library, Epistemonikos, and Trip Database. The results were clustered into three areas: sarcopenia and IMRDs, sarcopenia and biological disease-modifying antirheumatic drugs (bDMARDs), and nutritional interventions for sarcopenia.

Findings

Several cross-sectional studies have shown a higher prevalence of sarcopenia in IMRDs, such as rheumatoid arthritis. Although not fully established, evidence linking sarcopenia and other IMRDs (ankylosing spondylitis and systemic sclerosis) has been also described. For secondary sarcopenia prevention and treatment, bDMARDs’ administration proved efficacy in patients with rheumatoid arthritis. Furthermore, there is growing evidence linking nutrition to the prevention and treatment of sarcopenia. Evidence linking unfavourable results in nutritional risk assessment, insufficient intake of protein, vitamin D, antioxidant nutrients, and long-chain polyunsaturated fatty acids and sarcopenia have been reported.

Conclusion

Given that sarcopenia and IMRDs have strong links, further research is needed to improve patient care.
Robust semi-supervised non-negative matrix factorization for binary subspace learning
Authors: Dai Xiangguang , Zhang Keke , Li Juntang , Xiong Jiang , Zhang Nian , Li Huaqing
Published: February 2021

Non-negative matrix factorization and its extensions were applied to various areas (i.e., dimensionality reduction, clustering, etc.). When the original data are corrupted by outliers and noise, most of non-negative matrix factorization methods cannot achieve robust factorization and learn a subspace with binary codes. This paper puts forward a robust semi-supervised non-negative matrix factorization method for binary subspace learning, called RSNMF, for image clustering. For better clustering performance on the dataset contaminated by outliers and noise, we propose a weighted constraint on the noise matrix and impose manifold learning into non-negative matrix factorization. Moreover, we utilize the discrete hashing learning method to constrain the learned subspace, which can achieve a binary subspace from the original data. Experimental results validate the robustness and effectiveness of RSNMF in binary subspace learning and image clustering on the face dataset corrupted by Salt and Pepper noise and Contiguous Occlusion.
A Review of Gear Fault Diagnosis of Planetary Gearboxes Using Acoustic Emissions
Authors: Leaman Félix , Vicuña Cristián Molina , Clausen Elisabeth
Published: February 2021

Despite the progress made in the last decades in the field of machine condition monitoring, there are still cases where the current state of the art is not enough and new technologies and advanced analysis methods are required to prevent unexpected failures. One example is planetary gearboxes (PGs), which are one of the main components of mechanical transmission systems in heavy-duty machines such as off-highway trucks, electric rope shovels, helicopters and wind turbines. Although those machines are usually equipped with vibration and temperature sensors to detect faults in mechanical components, these technologies might not be able to perform well under certain circumstances. Therefore, the applied investigation on new monitoring technologies in the field of machine condition monitoring is a necessary step. Among those, in this review the acoustic emission technology will be addressed as a tool for fault diagnosis of gear faults in PG.
The Long Shadow of Fatalism: a Philosophical Speculation on Forster’s “the Machine Stops” (1909) on the Disintegration of Technologically Advanced Societies Back Then and Today
Authors: Seele Peter
Published: February 2021

EM Forster’s short story “The Machine Stops” from 1909 is widely reread and discussed again for some ten years as it portrays a science-fiction world resting on similar technological advancements as today in the digital era. Also management literature reviewed the short story with regard to centralized decision making, rationality and totalitarianism. I argue instead, that the main theme of the short story is – in Forster’s own words – the closing of a civilization in times of transition and facing major challenges. I built the argument by original quotes from Forster and by portraying the years 1906–9, when Forster developed the short story. This era before the Great War starting in 1914 was characterized by euphoric ‘futurism’ based on groundbreaking innovations like ‘long distance messaging’, ‘penny post’, ‘animated films’, Ford’s assembly line, ‘Olivetti typewriter’, ‘feature film’, ‘large ships’ and ‘air transportation’ – the ingredients of the short story as I argue. At the same time these acquitted years were characterized by increasing disintegration, instability, rebellions and a financial crisis with bailout programs. Based on the analogy and as part of speculative philosophy I reconstruct the current great challenges with Forster’ shadow of fatalism and arrive at the urgency to put more effort in addressing and researching pathways out of the crisis and towards stabilization of business and society.
Non-Newtonian effect on heat transfer and entropy generation of natural convection nanofluid flow inside a vertical wavy porous cavity
Authors: Tasmin Mahbuba , Nag Preetom , Hoque Zarin T. , Molla Md. Mamun
Published: February 2021

A numerical study on heat transfer and entropy generation in natural convection of non-Newtonian nanofluid flow has been explored within a differentially heated two-dimensional wavy porous cavity. In the present study, copper (Cu)–water nanofluid is considered for the investigation where the specific behavior of Cu nanoparticles in water is considered to behave as non-Newtonian based on previously established experimental results. The power-law model and the Brinkman-extended Darcy model has been used to characterize the non-Newtonian porous medium. The governing equations of the flow are solved using the finite volume method with the collocated grid arrangement. Numerical results are presented through streamlines, isotherms, local Nusselt number and entropy generation rate to study the effects of a range of Darcy number (Da), volume fractions (ϕ) of nanofluids, Rayleigh numbers (Ra), and the power-law index (n). Results show that the rate of heat transfer from the wavy wall to the medium becomes enhanced by decreasing the power-law index but increasing the volume fraction of nanoparticles. Increase of porosity level and buoyancy forces of the medium augments flow strength and results in a thinner boundary layer within the cavity. At negligible porosity level of the enclosure, effect of volume fraction of nanoparticles over thermal conductivity of the nanofluids is imperceptible. Interestingly, when the Darcy–Rayleigh number $$Ra^*\gg 10$$

R

a
∗

≫
10

, the power-law effect becomes more significant than the volume fraction effect in the augmentation of the convective heat transfer process. The local entropy generation is highly dominated by heat transfer irreversibility within the porous enclosure for all conditions of the flow medium. The particular wavy shape of the cavity strongly influences the heat transfer flow pattern and local entropy generation. Interestingly, contour graphs of local entropy generation and local Bejan number show a rotationally symmetric pattern of order two about the center of the wavy cavity.
Utilization of sugarcane factories’ wastes as inexpensive source of nutrients and CO2 for microalgal biomass production: process coupling and potential evaluation
Authors: Zewdie Deribew Tefera , Ali Abubeker Yimam
Published: February 2021

One approach for the viable production of algal biomass is to couple its production with wastewater treatment plants, power and/or industrial plants. This is intended towards the utilization of the nutrients and the CO2 in the wastewater and in the flue gases of the industry respectively by the microalgae during their growth. In the present study microalgal biomass production was conceptually coupled with a sugar factory. The potential of the wastewater and the flue gas of the factory to support the growth of the microalgae was evaluated. Likewise the possible reduction of pollution by the microalgae was studied. The outputs from the coupled process were determined using the material and energy balance approach with a spread sheet. The cultivation model shows that 12 mg of total nitrogen (TN) and 7.4 mg of total phosphorus (TP) per liter of wastewater could be transferred to the algal growth ponds. It was found that there is a nitrogen deficit in the wastewater. With the supply of makeup nutrient, 120.5 tons/year microalgal biomass could be produced from the coupled process. Application of the assumptions resulted in the reduction of chemical oxygen demand (COD) (mg O2/L) from 2200 to 447, biological oxygen demand (BOD5) (mg O2/L) from 1200 to 207, TN (mg/L) from 15 to 0.6 and, TP (mg/L) from 10 to 1.5 in the wastewater. Integration of the sugarcane processing factories with algal biomass production is important for both biomass production and bioremediation.
OGP: A Repository of Experimentally Characterized O-Glycoproteins to Facilitate Studies on O-Glycosylation
Authors: Huang Jiangming , Wu Mengxi , Zhang Yang , Kong Siyuan , Liu Mingqi , Jiang Biyun , Yang Pengyuan , Cao Weiqian
Published: February 2021

Numerous studies on cancers, biopharmaceuticals, and clinical trials have necessitated comprehensive and precise analysis of protein O-glycosylation. However, the lack of updated and convenient databases deters the storage of and reference to emerging O-glycoprotein data. To resolve this issue, an O-glycoprotein repository named OGP was established in this work. It was constructed with a collection of O-glycoprotein data from different sources. OGP contains 9354 O-glycosylation sites and 11,633 site-specific O-glycans mapping to 2133 O-glycoproteins, and it is the largest O-glycoprotein repository thus far. Based on the recorded O-glycosylation sites, an O-glycosylation site prediction tool was developed. Moreover, an OGP-based website is already available (https://www.oglyp.org/). The website comprises four specially designed and user-friendly modules: statistical analysis, database search, site prediction, and data submission. The first version of OGP repository and the website allow users to obtain various O-glycoprotein-related information, such as protein accession Nos., O-glycosylation sites, O-glycopeptide sequences, site-specific O-glycan structures, experimental methods, and potential O-glycosylation sites. O-glycosylation data mining can be performed efficiently on this website, which will greatly facilitate related studies. In addition, the database is accessible from OGP website (https://www.oglyp.org/download.php).
Cost Analysis of Pancreaticoduodenectomy at a High-Volume Robotic Hepatopancreaticobiliary Surgery Program
Authors: Rosemurgy Alexander , Ross Sharona , Bourdeau Timothy , Jacob Kevin , Thomas Ja'Karri , Przetocki Valerie , Luberice Kenneth , Sucandy Iswanto
Published: February 2021

BACKGROUND:

The robotic approach to pancreaticoduodenectomy is thought by many to be associated with increased financial burden for hospitals. We undertook this study to analyze and compare the cost of “open” pancreaticoduodenectomy with that associated with the application of the robotic surgical system to pancreaticoduodenectomy in our hepatobiliary program.

STUDY DESIGN:

With IRB approval, all patients undergoing pancreaticoduodenectomy at our institution, from August 2012 to November 2019, were prospectively followed. Cost, including total, variable, fixed-direct, fixed-indirect, and profitability for robotic and “open” pancreaticoduodenectomy were analyzed and compared. Data are presented as median (mean ± SD).

RESULTS:

There were 386 patients who underwent pancreaticoduodenectomy; 205 patients underwent robotic pancreaticoduodenectomy and 181 underwent “open” pancreaticoduodenectomy. Costs are presented as mean ± SD. Overall, the cost of care for robotic pancreaticoduodenectomy was $31,389 ($36,611 ± $20,545.40) vs $23,132 ($31,323 ± $28,885.50) for “open” pancreaticoduodenectomy (p = 0.04); total variable cost was $20,355 ($22,747 ± $11,127.60) vs $11,680 ($16,032 ± $14,817.20) (p = 0.01), total fixed direct cost was $1,999 ($2,330 ± $1,363.10) vs $2,073 ($2,983 ± $3,209.00) (p = 0.01), and total indirect cost was $7,217 ($9,354 ± $6,802.40) vs $6,802 ($9,505 ± $9,307.20) (p = 0.86), for robotic vs “open” pancreaticoduodenectomy, respectively. Since 2016, profitability was achieved in 29% of patients undergoing robotic pancreaticoduodenectomy.

CONCLUSIONS:

Robotic pancreaticoduodenectomy had lower estimated blood loss and shorter length of stay. Cost of care for robotic pancreaticoduodenectomy was greater across all categories, except for total indirect cost, than “open” pancreaticoduodenectomy. For our institution, profitability was accomplished in less than one-third of patients undergoing robotic pancreaticoduodenectomy. The role of the robotic platform for pancreaticoduodenectomy needs to be discussed among all stakeholders.
Nonspecial varieties and generalised Lang–Vojta conjectures
Authors: Rousseau Erwan , Turchet Amos , Wang Julie Tzu-Yueh
Published: February 2021

We construct a family of fibred threefolds

$X_m \to (S , \Delta )$

such that

$X_m$

has no étale cover that dominates a variety of general type but it dominates the orbifold

$(S,\Delta )$

of general type. Following Campana, the threefolds

$X_m$

are called weakly special but not special. The Weak Specialness Conjecture predicts that a weakly special variety defined over a number field has a potentially dense set of rational points. We prove that if m is big enough, the threefolds

$X_m$

present behaviours that contradict the function field and analytic analogue of the Weak Specialness Conjecture. We prove our results by adapting the recent method of Ru and Vojta. We also formulate some generalisations of known conjectures on exceptional loci that fit into Campana’s program and prove some cases over function fields.
Numerical experiments on firn isotope diffusion with the Community Firn Model
Authors: Gkinis Vasileios , Holme Christian , Kahle Emma C. , Stevens Max C. , Steig Eric J. , Vinther Bo M.
Published: February 2021

Advances in analytical methods have made it possible to obtain high-resolution water isotopic data from ice cores. Their spectral signature contains information on the diffusion process that attenuated the isotopic signal during the firn densification process. Here, we provide a tool for estimating firn-diffusion rates that builds on the Community Firn Model. Our model requires two main inputs, temperature and accumulation, and it calculates the diffusion lengths for δ17O, δ18O and δD. Prior information on the isotopic signal of the precipitation is not a requirement. In combination with deconvolution techniques, diffusion lengths can be used in order reconstruct the pre-diffusion isotopic signal. Furthermore, the temperature dependence of the isotope diffusion and firn densification makes the diffusion length an interesting candidate as a temperature proxy. We test the model under steady state and transient scenarios and compare four densification models. Comparisons with ice core data provide an evaluation of the four models and indicate that there are differences in their performance. Combining data-based diffusion length estimates with information on past accumulation rates and ice flow thinning, we reconstruct absolute temperatures from three Antarctic ice core sites.
Dialogue in polarized societies: women’s encounters with multiple others
Authors: Çelik Ayşe Betül , Göker Zeynep Gülru
Published: February 2021

Based on the analysis of a meeting with nineteen women from civil society with diverse backgrounds, invited to discuss what has gone wrong in Turkey’s Kurdish peace process and what women can do for peace in a highly polarized atmosphere, this article explores women’s dialogue in a conflict situation. With insights from deliberative and agonistic perspectives, the article shows that in a multiple-identity conflict, topical shifts in dialogue are accompanied by shifting alliances. The search for mutual definitions on conflictual issues renders the deliberation of sensitive issues difficult, so women circumvent polarizing discourses through indirect and covert language. However, the discussion of gender-based experiences with direct, contestational language helps women underline shared issues and address resentments. Dialogue’s transformative potential also depends on the existence of trust and an intersectionality perspective for which further dialogic initiatives should develop strategies.
When Are Legislators Responsive to Ethnic Minorities? Testing the Role of Electoral Incentives and Candidate Selection for Mitigating Ethnocentric Responsiveness
Authors: DINESEN PETER THISTED , DAHL MALTE , SCHIØLER MIKKEL
Published: February 2021

Previous studies have documented ethnic/racial bias in politicians’ constituency service, but less is known about the circumstances under which such ethnocentric responsiveness is curbed. We propose and test two hypotheses in this regard:the electoral incentives hypothesis, predicting that incentives for (re)election crowd out politicians’ potential biases, andthe candidate selection hypothesis, stipulating that minority constituents can identify responsive legislators by using candidates’ partisan affiliation and stated policy preferences as heuristics. We test these hypotheses through a field experiment on the responsiveness of incumbent local politicians in Denmark (N= 2,395), varying ethnicity, gender, and intention to vote for the candidate in the upcoming election, merged with data on their electoral performance and their stated policy preferences from a voting advice application. We observe marked ethnocentric responsiveness and find no indication that electoral incentives mitigate this behavior. However, minority voters can use parties’ and individual candidates’ stances on immigration to identify responsive politicians.
THE DOWER CHARTER OF OTTO II AND THEOPHANU, AND THE ROMAN SCRIPTORIUM AT SANTI APOSTOLI
Authors: Osborne John
Published: February 2021

Analyses of writing culture in tenth-century Rome have been impeded by an absence of manuscripts and documents that can be assigned unquestionably to scriptoria in the city. This paper will examine the possibility that one such document has hitherto been hiding in plain sight, as it were: the dower charter given by Emperor Otto II to the Byzantine princess Theophanu on the occasion of their marriage in St Peter's on 14 April 972. Usually considered to be ‘Ottonian’, rather than ‘Italian’ or ‘Roman’, this document nevertheless states explicitly that it was undertaken at the Roman church of Santi Apostoli, and this possibility is assessed in light of what is known about that church, the Via Lata region and their connections to the foremost noble family in the city.
Topological characterisation of rational maps with Siegel disks
Authors: ZHANG GAOFEI
Published: February 2021

We extend Thurston’s topological characterisation theorem for postcritically finite rational maps to a class of rational maps which have a fixed bounded type Siegel disk. This makes a small step towards generalizing Thurston’s theorem to geometrically infinite rational maps.
Adjuvant therapy in the management of operable salivary duct carcinoma: correlating evidence with a retrospective review
Authors: Venkatasai Jeyaanth , Das Anindita , Kaliamurthi Punitha , Sasidharan Balu Krishna , Mathew Manu , Singh Ashish , Irodi Aparna , Thomas Meera , John Subhashini , Michael Rajiv C. , Tirkey Amit J. , Isiah Rajesh , Pavamani Simon
Published: February 2021

Background:

Salivary duct carcinoma (SDC) is an extremely rare and aggressive subtype of salivary gland cancer with high morbidity and mortality and poor response to treatment. The current options of treatment include radical surgery followed by radiotherapy (RT) with or without chemotherapy. The aim of this study was to analyse the patterns of recurrences, possible predictors of outcome and role of RT in a cohort of patients with non-metastatic SDC.

Methods:

A retrospective review of patients treated between 2010 and 2019 with histologically proven non-metastatic SDC was conducted.

Results:

Sixteen patients were included in the series. Median follow-up was 25 months. Progression-free survival (PFS) and overall survival (OS) at 12 months were 61% and 80%, respectively. Seven out of the 16 patients had disease progression, distant metastases being most frequent. Four patients died due to disease progression. PFS was significantly worse for patients with pathological neck node positivity (p = 0·036) and peri-parotid nodes (p = 0·007). Local control was significantly associated with RT (p = 0·011). Addition of any chemotherapy, regardless of either concurrent or adjuvant, had no impact on the PFS or OS. Pathological neck node positivity with nodal stage of N2 or higher correlated significantly with worse OS (p = 0·031).

Conclusion:

Salivary ductal carcinoma is an aggressive malignancy with high metastatic potential. Inferior prognosis was observed among patients who had metastatic deposits in either cervical nodes or peri-parotid nodes on histopathology. As systemic failures are more predominant among these patients, larger prospective trials are needed to formulate an optimum strategy for choice and sequencing of first-line systemic therapy.
Grammatical Gender in the German Multiethnolect
Authors: Auer Peter , Siegel Vanessa
Published: February 2021

While major restructurings and simplifications have been reported for gender systems of other Germanic languages in multiethnolectal speech, this article demonstrates that the three-way gender distinction of German is relatively stable among young speakers from an immigrant background. We investigate gender in a German multiethnolect based on a corpus of approximately 17 hours of spontaneous speech produced by 28 young speakers in Stuttgart (mainly from Turkish and Balkan background). German is not their second language, but (one of) their first language(s), which they have fully acquired from childhood. We show that the gender system does not show signs of reduction in the direction of a two-gender system, nor of wholesale loss. We also argue that the position of gender in the grammar is weakened by independent innovations, such as the frequent use of bare nouns in grammatical contexts where German requires a determiner. Another phenomenon that weakens the position of gender is the simplification of adjective-noun agreement and the emergence of a generalized gender-neutral suffix for prenominal adjectives (that is, schwa). The disappearance of gender and case marking in the adjective means that the grammatical category of gender is lost in Adj + N phrases (without a determiner).
Weighing Psycholinguistic and Social Factors for Semantic Agreement in Dutch Pronouns
Authors: De Vos Lien , De Sutter Gert , De Vogelaer Gunther
Published: February 2021

Previous research has shown that Dutch pronominal gender is in a process of resemanticization: Highly individuated nouns are increasingly referred to with masculine and feminine pronouns, and lowly individuated ones with the neuter pronounhet/’t‘it’, irrespective of the grammatical gender of the noun (Audring 2009). The process is commonly attributed to the loss of adnominal gender agreement, which is increasingly blurring distinctions between masculine and feminine nouns and, therefore, requires speakers to resort to semantic default strategies (De Vogelaer & De Sutter 2011). Several factors have been identified that influence the choice of semantic vis-à-vis lexical agreement, both linguistic and social. This article seeks to weigh the importance of both structural and social factors in pronominal gender agreement in Belgian Dutch, using the Belgian part of the Spoken Dutch Corpus. A multivariate statistical analysis reveals that most effects are structural, including noun semantics and the syntactic function of the antecedent and the pronoun, as well as the pragmatic status of the antecedent. The most important social factor is speech register. We argue that these effects support a psycholinguistic account in which resemanticization is seen as a change from below, caused by hampered lexical access to noun gender.
Internal barriers to efficiency: why disinvestments are so difficult. Identifying and addressing internal barriers to disinvestment of health technologies
Authors: Hofmann Bjørn
Published: February 2021

Although efficiency is a core concept in health economics, its impact on health care practice still is modest. Despite an increased pressure on resource allocation, a widespread use of low-value care is identified. Nonetheless, disinvestments are rare. Why is this so? This is the key question of this paper: why are disinvestments not more prevalent and improving the efficiency of the health care system, given their sound foundation in health economics, their morally important rationale, the significant evidence for a long list of low-value care and available alternatives? Although several external barriers to disinvestments have been identified, this paper looks inside us for mental mechanisms that hamper rational assessment, implementation, use and disinvestment of health technologies. Critically identifying and assessing internal inclinations, such as cognitive biases, affective biases and imperatives, is the first step toward a more rational handling of health technologies. In order to provide accountable and efficient care we must engage in the quest against the figments of our minds; to disinvest in low-value care in order to provide high-value health care.
Euphotic Zone Metabolism in the North Pacific Subtropical Gyre Based on Oxygen Dynamics
Authors: Ferrón Sara , Barone Benedetto , Church Matthew J. , White Angelicque E. , Karl David M.
Published: February 2021

We report in situ rates of gross oxygen production (GOP), community respiration (R), and net community production (NCP) in the North Pacific Subtropical Gyre derived from mixed layer O2/Ar measurements. The measurements were conducted between November 2013 and January 2019 at the site of the Hawaii Ocean Time‐series program. Biological O2 concentration anomalies in the mixed layer showed a consistent diel variation, with values increasing during daytime due to net community production and decreasing during nighttime due to respiration. In situ mixed layer GOP and R, determined from these variations, covaried but showed no clear seasonal pattern, averaging 0.9 and 0.8 mmol O2 m−3 d−1, respectively. In situ rates of NCP determined from mixed layer O2/Ar ranged between −1.2 and 16.6 mmol O2 m−2 d−1. Our analyses indicate that at certain times of the year the diapycnal flux of O2 across the base of the mixed layer may be non‐negligible and, therefore, a fraction of O2/Ar‐derived NCP may form below the mixed layer. The seasonal climatology of NCP below the mixed layer (down to 150 m) was also estimated using near‐monthly changes in dissolved O2 concentrations. These calculations allowed us to estimate NCP for the entire euphotic zone (0–150 m), which shows pronounced seasonality, with a maximum in April‐May and a minimum in December, when the ecosystem becomes temporarily net heterotrophic. Annual NCP was estimated to be 2.1 ± 0.6 mol O2 m−2 yr−1, approximately 1.7 times the export of C through sinking particles captured in sediment traps at 150 m.
Zonal‐Scale of the Madden‐Julian Oscillation and Its Propagation Speed on the Interannual Time‐Scale
Authors: Lyu Mengxia , Jiang Xianan , Wu Zhiwei , Kim Daehyun , Adames Ángel F.
Published: February 2021

While no significant long‐term trend in the propagation speed of the Madden‐Julian Oscillation (MJO) in boreal winter is found during the past decades, pronounced year‐to‐year variability of the MJO phase speed is illustrated by analyzing a century‐long record data set. During the winters when fast MJO propagation is observed, the MJO exhibits a much larger zonal‐scale than that during the winters with slow propagation. A broader extension in MJO circulation effectively induces stronger and broader lower‐tropospheric moistening (drying) to the east (west) of MJO through horizontal moisture advection, prompting a faster MJO phase speed. The larger MJO zonal‐scale during the fast MJO propagation winters is coincident with anomalously increased background sea surface temperatures and precipitable water over both the western Indian Ocean and central/eastern Pacific, reminiscent of an expansion of the Indo‐Pacific warm pool. A fundamental question remains open regarding the key processes that determine the zonal‐scale of MJO organization.
COVID‐19 Crisis Reduces Free Tropospheric Ozone Across the Northern Hemisphere
Authors: Steinbrecht Wolfgang , Kubistin Dagmar , Plass‐Dülmer Christian , Davies Jonathan , Tarasick David W. , von der Gathen Peter , Deckelmann Holger , Jepsen Nis , Kivi Rigel , Lyall Norrie , Palm Matthias , Notholt Justus , Kois Bogumil , Oelsner Peter , Allaart Marc , Piters Ankie , Gill Michael , Van Malderen Roeland , Delcloo Andy W. , Sussmann Ralf , Mahieu Emmanuel , Servais Christian , Romanens Gonzague , Stübi Rene , Ancellet Gerard , Godin‐Beekmann Sophie , Yamanouchi Shoma , Strong Kimberly , Johnson Bryan , Cullis Patrick , Petropavlovskikh Irina , Hannigan James W. , Hernandez Jose‐Luis , Diaz Rodriguez Ana , Nakano Tatsumi , Chouza Fernando , Leblanc Thierry , Torres Carlos , Garcia Omaira , Röhling Amelie N. , Schneider Matthias , Blumenstock Thomas , Tully Matt , Paton‐Walsh Clare , Jones Nicholas , Querel Richard , Strahan Susan , Stauffer Ryan M. , Thompson Anne M. , Inness Antje , Engelen Richard , Chang Kai‐Lan , Cooper Owen R.
Published: February 2021

Throughout spring and summer 2020, ozone stations in the northern extratropics recorded unusually low ozone in the free troposphere. From April to August, and from 1 to 8 kilometers altitude, ozone was on average 7% (≈4 nmol/mol) below the 2000–2020 climatological mean. Such low ozone, over several months, and at so many stations, has not been observed in any previous year since at least 2000. Atmospheric composition analyses from the Copernicus Atmosphere Monitoring Service and simulations from the NASA GMI model indicate that the large 2020 springtime ozone depletion in the Arctic stratosphere contributed less than one‐quarter of the observed tropospheric anomaly. The observed anomaly is consistent with recent chemistry‐climate model simulations, which assume emissions reductions similar to those caused by the COVID‐19 crisis. COVID‐19 related emissions reductions appear to be the major cause for the observed reduced free tropospheric ozone in 2020.
Modulation of Magnetospheric Substorm Frequency: Dipole Tilt and IMF By Effects
Authors: Ohma A. , Reistad J. P. , Hatch S. M.
Published: February 2021

Substorm activity is heavily influenced by the Interplanetary Magnetic Field (IMF) Bz component and magnetospheric substorms occur most frequently when Bz is strongly negative. The substorm occurrence rate is also affected by the magnitude of the By component, but it is usually presumed that this contribution is independent of the sign of By. Using five independent substorm onset lists, we show that substorm activity does depend on the sign of By near the solstices. Specifically, we show that substorms occur more frequently when By and the dipole tilt angle Ψ have different signs as opposed to when they have the same sign. These results confirm that the magnetosphere exhibits an explicit dependence on the polarity of By for nonzero Ψ, as other recent studies have suggested, and imply variation in the dayside reconnection rate and/or the magnetotail response. On the other hand, we find no clear relationship between substorm intensity and By regardless of Ψ. Last, for the onset list based on identifying negative bays at auroral latitudes, we observe an overall trend of more frequent onsets for positive By, regardless of season. However, substorm frequency in the other four substorm lists does not exhibit an overall preference for positive By. We show that this phenomenon is very likely a consequence of the particular substorm identification method (i.e., identification of negative bays), which is affected by local ionospheric conditions that depend on By and Ψ.
Surface Currents and Significant Wave Height Gradients: Matching Numerical Models and High‐Resolution Altimeter Wave Heights in the Agulhas Current Region
Authors: Marechal Gwendal , Ardhuin Fabrice
Published: February 2021

Advances in the understanding and modeling of surface currents have revealed the importance of internal waves, mesoscale and submesoscale features. Indeed, all these features should have a large influence on wind waves and in particular on wave heights. Still, the quantitative impact of currents on waves is not well known due to the complexity of the random wavefields and currents that are found in the ocean and the lack of observations of both currents and waves at scales shorter than 150 km. Here, we compare novel satellite altimetry data and state of the art phase‐averaged numerical wave models forced both by wind and currents. Currents used are taken from the oceanic model Coastal and Regional Ocean COmmunity, run at high resolution. The influence of current field resolution is investigated by applying Gaussian filters of different width to that same high‐resolution current field. We find that a numerical wave model that uses currents with resolutions of ∼30 km or less and a directional resolution of 7.5° can provide accurate representations of the significant wave height gradients found in the Agulhas current. Using smoother current fields such as derived from altimeters measurements alone, coarse directional spectral resolution or larger directional spread of the wave model generally underestimates gradients and extreme wave heights. Hence, satellite altimetry provides high‐resolution wave height with a gradient magnitude that is highly sensitive to underlying surface current gradients, at resolutions that may not be resolved by today's altimeters measurements. This is demonstrated here for relatively steady currents averaged over 3 years.
A Comodulation Analysis of Atmospheric Energy Injection Into the Ground Motion at InSight, Mars
Authors: Charalambous C. , Stott A. E. , Pike W. T. , McClean J. B. , Warren T. , Spiga A. , Banfield D. , Garcia R. F. , Clinton J. , Stähler S. , Navarro S. , Lognonné P. , Scholz J.‐R. , Kawamura T. , van Driel M. , Böse M. , Ceylan S. , Khan A. , Horleston A. , Orhand‐Mainsant G. , Sotomayor L. M. , Murdoch N. , Giardini D. , Banerdt W. B.
Published: February 2021

Seismic observations involve signals that can be easily masked by noise injection. For the NASA Mars lander InSight, the atmosphere is a significant noise contributor, impeding the identification of seismic events for two‐thirds of a Martian day. While the noise is below that seen at even the quietest sites on Earth, the amplitude of seismic signals on Mars is also considerably lower, requiring an understanding and quantification of environmental injection at unprecedented levels. Mars’ ground and atmosphere are a continuously coupled seismic system, and although atmospheric functions are of distinct origins, the superposition of these noise contributions is poorly understood, making separation a challenging task. We present a novel method for partitioning the observed signal into seismic and environmental contributions. Atmospheric pressure and wind fluctuations are shown to exhibit temporal cross‐frequency coupling across multiple bands, injecting noise that is neither random nor coherent. We investigate this through comodulation, quantifying the synchrony of the seismic motion, wind and pressure signals. By working in the time‐frequency domain, we discriminate between the different origins of underlying processes and determine the site's environmental sensitivity. Our method aims to create a virtual vault at InSight's landing site on Mars, shielding the seismometers with effective postprocessing in lieu of a physical vault. This allows us to describe the environmental and seismic signals over a sequence of sols, to quantify the wind and pressure injection and estimate the seismic content of possible marsquakes with a signal‐to‐noise ratio that can be quantified in terms of environmental independence. Finally, we exploit the relationship between the comodulated signals to identify their sources.
TGF-β1-mediated transition of resident fibroblasts to cancer-associated fibroblasts promotes cancer metastasis in gastrointestinal stromal tumor
Authors: Yoon Hyunho , Tang Chih-Min , Banerjee Sudeep , Delgado Antonio L. , Yebra Mayra , Davis Jacob , Sicklick Jason K.
Published: February 2021

Cancer-associated fibroblasts (CAFs) are the most abundant cells in the tumor microenvironment. Crosstalk between tumor cells and CAFs contributes to tumor survival in most epithelial cancers. Recently, utilizing gastrointestinal stromal tumor (GIST) as a model for sarcomas, we identified paracrine networks by which CAFs promote tumor progression and metastasis. However, the mechanisms by which CAFs arise in sarcomas remain unclear. Here, RNA sequencing analysis revealed that transforming growth factor-β1 (TGF-β1) is highly expressed in both tumor cells and CAFs. To determine the functional role of TGF-β1, we treated normal gastric fibroblasts (GFs) with recombinant TGF-β1, which caused the GFs to adopt a more stellate morphology, as well as increased the mRNA expression of CAF-mediated genes (CCL2, RAB3B, and TNC) and genes encoding fibroblast growth factors (FGFs). Moreover, while either GIST or CAF conditioned media enhanced the transition from GFs to CAFs, a TGF-β1-blocking antibody attenuated this effect. Transwell migration assays revealed that the TGF-β1-mediated transition from GFs to CAFs enhanced tumor cell migration. This migratory effect was abrogated by an anti-TGF-β1 antibody, suggesting that TGF-β1 secreted from GIST cells or CAFs is associated with GIST migration via GF-to-CAF transition. In addition, the murine spleen-to-liver metastasis model showed that GF pre-treated with TGF-β1 promoted GIST metastasis. Collectively, these findings reveal unappreciated crosstalk among tumor cells, CAFs, and normal resident fibroblasts in the stroma of sarcomas, which enhances a GF-to-CAF transition associated with tumor migration and metastasis.
Increasing flavonoid concentrations in root exudates enhance associations between arbuscular mycorrhizal fungi and an invasive plant
Authors: Tian Baoliang , Pei Yingchun , Huang Wei , Ding Jianqing , Siemann Evan
Published: February 2021

Many invasive plants have enhanced mutualistic arbuscular mycorrhizal (AM) fungal associations, however, mechanisms underlying differences in AM fungal associations between introduced and native populations of invasive plants have not been explored. Here we test the hypothesis that variation in root exudate chemicals in invasive populations affects AM fungal colonization and then impacts plant performance. We examined flavonoids (quercetin and quercitrin) in root exudates of native and introduced populations of the invasive plant Triadica sebifera and tested their effects on AM fungi and plant performance. We found that plants from introduced populations had higher concentrations of quercetin in root exudates, greater AM fungal colonization and higher biomass. Applying root exudates more strongly increased AM fungal colonization of target plants and AM fungal spore germination when exudate donors were from introduced populations. The role of root exudate chemicals was further confirmed by decreased AM fungal colonization when activated charcoal was added into soil. Moreover, addition of quercetin into soil increased AM fungal colonization, indicating quercetin might be a key chemical signal stimulating AM fungal associations. Together these results suggest genetic differences in root exudate flavonoids play an important role in enhancing AM fungal associations and invasive plants’ performance, thus considering root exudate chemicals is critical to unveiling mechanisms governing shifting plant-soil microbe interactions during plant invasions.
Seventy years of data from the world’s longest grazed and irrigated pasture trials
Authors: McDowell Rich. W. , Moss R. A. , Gray C. W. , Smith L. C. , Sneath G.
Published: February 2021

Pastures are the most widespread land use, globally. The Winchmore trials were established in 1948–1949 in Canterbury, New Zealand and examined either different rates of phosphorus (P) fertiliser on the same irrigation schedule (Fertiliser trial), or different irrigation scheduling at the same rate of P application (Irrigation trial). About 96,000 records of soil chemistry and physical data and pasture yield and botanical composition are available along with nearly 7000 soil samples. These data have been used in 475 publications that have explored topics as diverse as: improvements in sheep, dairy and deer production; the efficacy and scheduling of irrigation; improvements in pasture and crop production; agronomic and environmental soil and water research; and entomology. In addition to above topics, these data are invaluable for calibrating models to predict long-term issues like the accumulation of soil carbon or contaminants like cadmium and informing policy on climate change and agricultural practices. The data and soil samples are available for use and may yet yield discoveries, unforeseen 70 years ago.
Solanum linnaeanum and Solanum sisymbriifolium as a sustainable strategy for the management of Meloidogyne chitwoodi
Authors: Perpétuo Laura Soraia , da Cunha Maria J. M. , Batista Maria Teresa , Conceição Isabel Luci
Published: February 2021

Root-knot nematodes (RKN), Meloidogyne spp., are important crop pests that cause severe losses in crop production worldwide, reducing both productivity and crop quality. Meloidogyne chitwoodi Golden, O'Bannon, Santo & Finley, 1980 is considered a quarantine organism by the European and Mediterranean Plant Protection Organization (EPPO) causing damage in tomato and potato crops. The development of nonchemical and sustainable management strategies to reduce nematode damage is crucial. The resistance of Solanum linnaeanum Hepper & P.-M.L. Jaeger and S. sisymbriifolium Lamarck cv. Sis 6001 to M. chitwoodi was evaluated based on gall index (GI), the Bridge & Page (1980) rating chart and reproduction factor (RF). Both plant species were resistant to M. chitwoodi. Solanum linnaeanum had an average of 519 small root swellings/plant, with 45% adult nematodes inside the roots, all males. Solanum sisymbriifolium had GI ≤ 2 and RF ≤ 1 with a high percentage (69%) of nematodes inside the roots that did not develop beyond the sexually undifferentiated second-stage. The use of S. linnaeanum as a new source of resistance is a good alternative for the control of RKN in the quest to develop nonchemical and sustainable management strategies to protect crops.
Changes in parafoveal and peripapillary perfusion after decompression surgery in chiasmal compression due to pituitary tumors
Authors: Lee Ga-In , Park Kyung-Ah , Oh Sei Yeul , Kong Doo-Sik
Published: February 2021

We evaluated changes in parafoveal and peripapillary vessel density in chiasmal compression after decompression surgery using optical coherence tomography angiography (OCT-A). Sixty-two eyes with chiasmal compression for which preoperative and postoperative (4–6 months) OCT, OCT-A, visual field (VF), and comprehensive ophthalmic data were available, and 44 healthy eyes were evaluated. Vessel densities of the superficial retinal capillary plexus (SRCP), deep retinal capillary plexus (DRCP), and radial peripapillary capillary (RPC) segment were assessed using OCT-A. The postoperative measurements were compared with preoperative data. Preoperative peripapillary retinal nerve fiber layer, macular ganglion cell-inner plexiform layer thickness, and vessel densities of SRCP and RPC segments in patients’ eyes were significantly reduced compared to those of healthy controls (P < 0.0001, P < 0.0001, P = 0.0052, and P = 0.0085, respectively). Vessel densities were significantly decreased in the SRCP (P < 0.0001), DRCP (P = 0.0017), and RPC segments (P < 0.0001) after surgery compared to the preoperative values. Significant associations between the postoperative SRCP and DRCP vessel density changes and preoperative SRCP (r =  − 0.3195, P = 0.0114) and DRCP (r =  − 0.5165, P < 0.0001) vessel densities were found, respectively. There were also significant associations between postoperative SRCP vessel density changes and VF changes (r =  − 0.2586, P = 0.0424). These findings indicate that decreased perfusion around the optic nerve head and on the macula associated with chiasmal compression could further progress after decompression surgery. Further functional and longer-term clinical studies are needed to elucidate the clinical implications of these findings.