bluuebunny/crossref_metadata_2025_split huggingface dataset:
Testing the influence of crushing surface variation on seed-cracking performance among beak morphs of the African seedcracker Pyrenestes ostrinus
Authors: Heckeberg Nicola S. , Anderson Philip S. L. , Rayfield Emily J. 
Published: February 2021

ABSTRACT
Extreme phenotypic polymorphism is an oft-cited example of evolutionary theory in practice. Although these morphological variations are assumed to be adaptive, few studies have biomechanically tested such hypotheses. Pyrenestes ostrinus (the African seedcracker finch) shows an intraspecific polymorphism in beak size and shape that is entirely diet driven and allelically determined. Three distinct morphs feed upon soft sedge seeds during times of abundance, but during lean times switch to specializing on three different species of sedge seeds that differ significantly in hardness. Here, we test the hypothesis that beak morphology is directly related to consuming seeds of different hardness. We used a novel experimental analysis to test how beak morphology affects the efficiency of cracking sedge seeds of variable hardness, observing that neither mandibular ramus width nor crushing surface morphology had significant effects on the ability to crack different seed types. It is likely that feeding performance is correlated with other aspects of beak size and shape, such as beak depth and strength, muscle force or gape. Our results highlight how even seemingly straightforward examples of adaptive selection in nature can be complex in practice.
Improving spring–mass parameter estimation in running using nonlinear regression methods
Authors: Burns Geoffrey T. , Gonzalez Richard , Zernicke Ronald F. 
Published: February 2021

ABSTRACT
Runners are commonly modeled as spring–mass systems, but the traditional calculations of these models rely on discrete observations during the gait cycle (e.g. maximal vertical force) and simplifying assumptions (e.g. leg length), challenging the predicative capacity and generalizability of observations. We present a method to model runners as spring–mass systems using nonlinear regression (NLR) and the full vertical ground reaction force (vGRF) time series without additional inputs and fewer traditional parameter assumptions. We derived and validated a time-dependent vGRF function characterized by four spring–mass parameters – stiffness, touchdown angle, leg length and contact time – using a sinusoidal approximation. Next, we compared the NLR-estimated spring–mass parameters with traditional calculations in runners. The mixed-effect NLR method (ME NLR) modeled the observed vGRF best (RMSE:155 N) compared with a conventional sinusoid approximation (RMSE: 230 N). Against the conventional methods, its estimations provided similar stiffness approximations (−0.2±0.6 kN m−1) with moderately steeper angles (1.2±0.7 deg), longer legs (+4.2±2.3 cm) and shorter effective contact times (−12±4 ms). Together, these vGRF-driven system parameters more closely approximated the observed vertical impulses (observed: 214.8 N s; ME NLR: 209.0 N s; traditional: 223.6 N s). Finally, we generated spring–mass simulations from traditional and ME NLR parameter estimates to assess the predicative capacity of each method to model stable running systems. In 6/7 subjects, ME NLR parameters generated models that ran with equal or greater stability than traditional estimates. ME NLR modeling of the vGRF in running is therefore a useful tool to assess runners holistically as spring–mass systems with fewer measurement sources or anthropometric assumptions. Furthermore, its utility as statistical framework lends itself to more complex mixed-effects modeling to explore research questions in running.
Controlled expression of the migratory phenotype affects oxidative status in birds
Authors: Marasco Valeria , Sebastiano Manrico , Costantini David , Pola Gianni , Fusani Leonida 
Published: February 2021

ABSTRACT
High caloric intake can increase production of reactive oxygen and nitrogen species. We examined whether the emergence of the migratory phenotype, primarily signalled by increased food intake and fuelling, is accompanied by changes in oxidative status. We induced autumn migration followed by a non-migratory wintering phase in common quails (Coturnix coturnix). We compared three markers of oxidative status – oxidative damage to lipids expressed as thiobarbituric acid reactive substances (TBARS); superoxide dismutase (SOD); and glutathione peroxidase (GPx) – between birds sampled during the migratory and non-migratory phase. We found that the emergence of the migratory phenotype was associated with: (i) higher levels of TBARS in the liver; (ii) lower levels of SOD in red blood cells and, marginally, in the liver; (iii) higher levels of GPx in the pectoral muscle; and (iv) sex-specific changes in red blood cells and liver. We found no link between food intake and variation in markers of oxidative status in any of the tissues examined, despite food intake being higher in the migratory birds. However, the increase in body mass was positively correlated with muscle GPx activity as birds entered the pre-migratory fattening phase, while the amount of decrease in body mass was negatively correlated with muscle GPx as birds transitioned to the non-migratory phase. Such correlations were absent in red blood cells and liver. Our work suggests that during the emergence of the migratory phenotype, birds might strategically displace oxidative costs on the liver in order to safeguard the pectoral muscles, which have a fundamental role in successfully completing the migratory flight.
Rhythmic auditory stimuli modulate movement recovery in response to perturbation during locomotion
Authors: Ravi Deepak K. , Bartholet Marc , Skiadopoulos Andreas , Kent Jenny A. , Wickstrom Jordan , Taylor William R. , Singh Navrag B. , Stergiou Nick 
Published: February 2021

ABSTRACT
The capacity to recover after a perturbation is a well-known intrinsic property of physiological systems, including the locomotor system, and can be termed ‘resilience’. Despite an abundance of metrics proposed to measure the complex dynamics of bipedal locomotion, analytical tools for quantifying resilience are lacking. Here, we introduce a novel method to directly quantify resilience to perturbations during locomotion. We examined the extent to which synchronizing stepping with two different temporal structured auditory stimuli (periodic and 1/f structure) during walking modulates resilience to a large unexpected perturbation. Recovery time after perturbation was calculated from the horizontal velocity of the body's center of mass. Our results indicate that synchronizing stepping with a 1/f stimulus elicited greater resilience to mechanical perturbations during walking compared with the periodic stimulus (3.3 s faster). Our proposed method may help to gain a comprehensive understanding of movement recovery behavior of humans and other animals in their ecological contexts.
High carbohydrate diet ingestion increases post-meal lipid synthesis and drives respiratory exchange ratios above 1
Authors: Talal Stav , Cease Arianne , Farington Ruth , Medina Hector E. , Rojas Julio , Harrison Jon 
Published: February 2021

ABSTRACT
Locusts have been reported to elevate metabolic rate in response to high carbohydrate diets; this conclusion was based on metabolic rates calculated from CO2 production, a common practice for insects. However, respiratory exchange ratio (RER, CO2 production divided by O2 consumption) can rise above 1 as a result of de novo lipid synthesis, providing an alternative possible explanation of the prior findings. We studied the relationship between macronutrient ingestion, RER and lipid synthesis using South American locusts (Schistocerca cancellata) reared on artificial diets varying in protein:carbohydrate (p:c) ratio. RER increased and rose above 1 as dietary p:c ratio decreased. Lipid accumulation rates were strongly positively correlated with dietary carbohydrate content and ingestion. RERs above 1 were only observed for animals without food in the respirometry chamber, suggesting that hormonal changes after a meal may drive lipid synthesis. Schistocerca cancellata does not elevate metabolic rate on low p:c diets; in fact, the opposite trend was observed.
Association between convalescent plasma and the risk of mortality among patients with COVID-19: a meta-analysis
Authors: Wardhani Shinta Oktya , Fajar Jonny Karunia , Wulandari Laksmi , Soegiarto Gatot , Purnamasari Yeni , Asmiragani Anisa , Maliga Helnida Anggun , Ilmawan Muhammad , Seran Gloriana , Iskandar Dheka Sapti , Ndapa Conchita Emiliana , Hamat Viviana , Wahyuni Rafika Ajeng , Cyntia Linda Oktaviana Suci , Maarang Feronika Maryanti , Beo Yosef Andrian , Adar Olivera Agnes , Rakhmadhan Iraky Mardya , Shantikaratri Emilia Tiara , Putri Ayu Sekarani Damana , Wahdini Rizqa , Broto Endang Pati , Suwanto Agnes Wanda , Tamara Fredo , Mahendra Aditya Indra , Winoto Eden Suryoiman , Krisna Pratista Adi , Harapan Harapan 
Published: February 2021

Background: Convalescent plasma (CCP) has been used for treating some infectious diseases; however, the efficacy of CCP in coronavirus disease 2019 (COVID-19) remains controversial. The aim of this research was to assess the efficacy of CCP as an adjunctive treatment in COVID-19 patients. Methods: Four bibliographic databases and a preprint database were searched for potentially relevant articles. Mortality rates between patients treated with standard treatment and standard treatment with CCP were compared using a Z test. Results: A total of 1,937 patients treated with CCP and 3,405 patients without CCP retrieved from 12 studies were included. The risk of mortality was 1.92-fold higher in patients without CCP compared to patients treated with CCP (OR: 1.92; 95%CI: 1.33, 2.77; p=0.0005). In severe COVID-19 sub-group analysis, we found that patients without the CCP had a 1.32 times higher risk of mortality than those treated with the CCP (OR: 1.32; 95%CI: 1.09, 1.60; p=0.0040). Conclusions: CCP, as adjunctive therapy, reduces the mortality rate among COVID-19 patients.
Focus position in SOV ~ SVO-varying languages – evidence from Enets, Nganasan, and Dolgan
Authors: Däbritz Chris Lasse 
Published: February 2021

It is well known that the basic word order pattern of a language is closely intertwined with the syntactic realization of argument focus constituents. SVO languages exhibit a focus position at the sentence’s right periphery, SOV languages exhibit an immediately preverbal focus position. The study at hand examines both the basic word order patterns and the syntactic realization of focus in Enets, Nganasan and Dolgan. The major outcome is that Nganasan and Dolgan are much more flexible with respect to their basic word order pattern and, in consequence, exhibit both an immediately preverbal focus position and a right-peripheral focus position, whilst Enets realizes argument focus constituents almost exclusively immediately preverbally.
Kokkuvõte. Chris Lasse Däbritz: Fookuse asend SOV ~ SVO variatsiooniga keeltes – tõendus eenetsi, nganassaani ja dolgaani keeltest. On üldiselt teada, et ühe keele põhiline sõnajärjestus on tihedas seoses (kitsalt) fookustatud konstituentide süntaksiga. SVO keeltes on (kitsas) fookus reali seeritud lause paremas perifeerias, SOV keeltes on (kitsas) fookus realiseeritud vahetult verbi ees. Selles artiklis uuritakse nii põhilist sõnajärjestust kui ka fookuse süntaksit eenetsi, nganassaani ja dolgaani keeltes. Uurimuse kõige olulisem tulemus on see, et nganassaani ja dolgaani keeltes on põhiline sõnajärjestus tunduvalt paindlikum kui eenetsi keeles. Sellepärast realiseeritakse nganassaani ja dolgaani keeltes (kitsalt) fookustatud konstituendid nii vahetult verbi ees kui ka lause paremas perifeerias, samas kui eenetsi keeles realiseeritakse nad ainult vahetult verbi ees.
Аннотация. Крис Лассе Дэбриц: Позиция фокуса в языках с вариативным порядком слов SOV ~ SVO – данные энецкого, нганасанского и долганского языков. Как известно, базовый порядок слов в языке определяет синтаксическую позицию фокусных аргументов. В языках SVO фокусные составляющие ставятся в конце предложения, в языках SOV – непосредственно перед глаголом. В данной статье рассматриваются базовый порядок слов и позиция фокуса в энецком, нганасанском и долганском языках и показывается, что в нганасанском и долганском языках порядок слов намного более свободен и, соответственно, фокусные аргументы могут располагаться как перед глаголом, так и в конце предложения; а в энецком языке позиция фокуса – почти всегда непосредственно перед глаголом.
Converbal constructions in Selkup
Authors: Behnke Anja 
Published: February 2021

In Selkup, converbs and converbal constructions are extensively used in a wide range of different syntactic functions. However, the corpus data show significant differences regarding the frequency within the individual Selkup dialectal groups (Northern, Central and Southern). In Southern Selkup, converbal constructions occur more than three times more frequently than in Central and Northern Selkup. This southnorth divide can also be observed concerning some functions, especially complex predicates. The question arises why there is such a large difference in the frequency and which strategies Central and Northern Selkup use to express Southern Selkup converbal constructions.
Kokkuvõte. Anja Behnke: Konverbitarindid sölkupi keeles. Sölkupi keeles kasutatakse konverbe ja konverbitarindeid laialdaselt paljudes erinevates süntaktilistes funktsioonides. Siiski näitavad korpuseandmed märkimis väärseid esinemissageduse erinevusi sölkupi murrete lõikes (põhja-, kesk- ja lõunasölkupi). Lõuna-sölkupi murdes esinevad konverbitarindid enam kui kolm korda sagedamini kui kesk- ja põhja-sölkupi murretes. Sarnast põhja-lõuna vastandust on näha ka mõningate nende funktsioonide puhul, eriti liitpredikaatide puhul. Tekib küsimus, millest on selline esinemissageduste erinevus tingitud ja millised strateegiad vastavad kesk- ja põhja-sölkupi murretes lõunasölkupi konverbitarinditele.
Аннотация. Аня Бенке: Деепричастные конструкции в селькупском языке. В селькупском языке деепричастия и деепричастные конструкции широко используются в самых разных синтаксических позициях. Однако корпусные данные показывают значительные различия в частотности их употребления в разных диалектных группах (северной, центральной и южной). В южноселькупском конструкции с деепричастиями встречаются более чем в три раза чаще, чем в центральном и северном. Такое же разделение между севером и югом можно наблюдать и на примере некоторых функций, в особенности сложных предикатов. В этой связи возникают вопросы о причинах такой разницы в частотности и о том, какие стратегии используются в северном и центральном селькупском для выражения значений, которые в южноселькупском выражаются конструкциями с деепричастиями.
The background and research potential of the first Selkup books by N. P. Grigorovskij
Authors: Fedotova Nadezhda 
Published: February 2021

This article aims to explain why the dialectal identification of the Selkup texts compiled by Nikolaj Grigorovskij in the 19th century is still open. It also provides preliminary results on the isoglosses within the Southern dialectal group and strategies on how to address this problem. In order to advance the research, the first Selkup books of the 19th century (1879) have been converted into a digital annotated corpus of texts. Their analysis has revealed language features which, on the one hand, are accurately verified by Selkup material of the 20th century (on the example of the verb conjugation and the noun declension paradigms and the main Selkup isoglosses identified by Helimski. On the other hand, it has shown that the dialectal phenomena are insufficiently described. The article also gives the combined variant of Grigorovskij’s biography existing as fragments in different sources.
Kokkuvõte. Nadežda Fedotova: Esimeste N. P. Grigorovski sölkupi raamatute taust ja teaduslik potentsiaal. Siinse artikli eesmärk on välja selgitada, miks on siiani lahtine 19. sajandil Nikolaj Grigorovski poolt kogutud sölkupi tekstide murdeline määratlus. Ka annab artikkel esmased tulemused isoglosside piiride kohta lõuna-sölkupi murdegrupis ja pakub strateegiaid sellele probleemile lähenemiseks. Uurimisteema arendamiseks on esmalt esimesed 19. sajandi sölkupi raamatud (1879) viidud digitaalse tekstikorpuse kujule. Tekstianalüüs on välja toonud keelelised tunnused, mida ühest küljest kinnitavad ka 20. sajandi sölkupi materjalid (seda verbi pöördeliste ja noomenite käändeliste paradigmade põhjal ning põhiliste sölkupi isoglosside põhjal, mille on välja toonud Helimski 2004). Teisalt aga näitab analüüs, et murdelised nähtused on ebapiisavalt kirjeldatud. Artikkel sisaldab ka erinevates allikates esinevatest fragmentidest kokku kombineeritud varianti Grigorovski bibliograafiast.
Аннотация. Надежда Федотова: История и перспектива исследования первых книг на селькупском языке Н. П. Григоровского. Целью статьи является выявление причин, в связи с которыми проблема определения диалектной принадлежности первых селькупских текстов, собранных в XIX веке Николаем Григоровским, остается открытой. В статье даны предварительные варианты изоглосс, позволяющие отличить южную диалектную группу селькупского языка от других диалектных групп. С тем чтобы углубить исследование, первые селькупские книги XIX века (1879) были оцифрованы и преобразованы в аннотированный корпус текстов. Анализ на основе данного корпуса позволил обнаружить языковые явления, которые, с одной стороны, точно совпадают с селькупскими материалами, зафиксированными в XX веке (на примере парадигм спряжения селькупских глаголов и склонения существительных, а также с основными изоглоссами, предложенными Хелимским [Xelimskij 2004]). С другой стороны, они демонстрируют диалектные явления, которые недостаточно подробно описаны в литературе. В статье также предложена наиболее полная версия биографии Григоровского как компиляция из различных источников.
Covid-19 in Estonia. Restrictions and population’s coping with them
Authors: Tiit Ene-Margit , Makarova Marianna 
Published: February 2021

The article is based on a selection of data commissioned by the Government Office of the Republic of Estonia and received during 10 weeks from weekly surveys (COVID-THEMATIC SURVEY) conducted by Turu-uuringute AS, a market research company.
The study began on 17 March and lasted for 10 weeks to 21 May. On three days of every week, about 2,000 Estonian residents aged 15 and over were interviewed. The respondents were randomly selected and represented the entire population of Estonia in terms of gender, age, ethnicity and social affiliation.
The time series on the assessment of virus infections, hospital and intensive care (mechanical ventilation) and COVID deaths, compiled on the basis of data published by the Health Board, was also used as background information.
The first three rounds took place during the period of increasing morbidity, the following four rounds (4–7) during the study period when the morbidity situation remained more or less stable, and all the established restrictions also applied. The last stage, rounds 8–10, took place at a time when morbidity was declining and restrictions were gradually eased.
The survey revealed that Estonia was not ready for the crisis – just like most of the world’s countries. The crisis tested, on the one hand, the government’s ability to make difficult decisions and make significant use of the brain potential of the country’s research community, and, on the other hand, the people’s reasonableness, stress tolerance and ability to comply with rather awkward restrictions. It follows from the present analysis that all the restrictions were opposed by those who did not believe in their appropriateness. However, compared to the total population, their number was small, and, therefore, the restrictions in Estonia were maintained without sanctions and no contradictions arose, let alone unrest.
The open action of the Crisis Committee was very important: the number of new infections, the number of patients in need of hospital treatment and mechanical ventilation, as well as the number of deaths, were reported daily at both the government press conference and in the media. The survey showed that there were very few people in the country who thought they did not know everything they needed about the crisis. The fact that people remained rather cautious in their assessments even after the end of the emergency situation adds to the hope of coping with the virus in the future – should a second wave or any other threat come.
On the suitability of the distance between the tip of the nose and the middle of the elbow joint for sneezing etiquette as corona infection prophylaxis
Authors: Raschka Christoph , Heer Laura , Koch Horst Josef 
Published: February 2021

During the current corona pandemic, the question to which extent people could reach the middle of the elbow joint with the tip of their nose, which the Federal Ministry of Health recommended as a preventive measure when sneezing, was investigated with the help of an online questionnaire.
The analysis included 316 fully completed online questionnaires and 16 additional telephone interviews, a total of 332 test persons (average age 29.5 (± 14.3) years, average BMI 22.9 (± 3.4) kg/m²; 226 women, 106 men).
The results of this study show that 84.6% of respondents followed the recommended coughing etiquette and sneezed into the crook of their arm, 15.4% did not. The most common reason given for not using it was habit. Nevertheless, 92.8% of the participants found sneezing or coughing in the crook of their arm to be useful.
When measuring the distance, 76.2% of the participants were able to touch the crook of the arm at the specific angle on both sides. The average measured distance was 1.13 cm on the right and 1.23 cm on the left. It was found that the BMI and age had a significant relationship with the measured distance. In a gender-specific comparison, more women than men sneezed into the crook of their arm, while no significant differences were found when measuring the distance.
If the results of this study are put into practice, it makes perfect sense to continue to recommend sneezing or coughing in the crook of the arm. However, a note should be attached to this recommendation, which prompts one to take the sneeze position once and to check whether the crook of the arm can really be reached effectively. If this is not possible, alternative options should be recommended.