bluuebunny/crossref_metadata_2025_split huggingface dataset:
Changes in plant diversity in a water-limited and isolated high-mountain range (Sierra Nevada, Spain)
Authors: Lamprecht Andrea , Pauli Harald , Fernández Calzado Maria Rosa , Lorite Juan , Molero Mesa Joaquín , Steinbauer Klaus , Winkler Manuela 
Published: February 2021

AbstractClimate change impacts are of a particular concern in small mountain ranges, where cold-adapted plant species have their optimum zone in the upper bioclimatic belts. This is commonly the case in Mediterranean mountains, which often harbour high numbers of endemic species, enhancing the risk of biodiversity losses. This study deals with shifts in vascular plant diversity in the upper zones of the Sierra Nevada, Spain, in relation with climatic parameters during the past two decades. We used vegetation data from permanent plots of three surveys of two GLORIA study regions, spanning a period of 18 years (2001–2019); ERA5 temperature and precipitation data; and snow cover durations, derived from on-site soil temperature data. Relationships between diversity patterns and climate factors were analysed using GLMMs. Species richness showed a decline between 2001 and 2008, and increased thereafter. Species cover increased slightly but significantly, although not for endemic species. While endemics underwent cover losses proportional to non-endemics, more widespread shrub species increased. Precipitation tended to increase during the last decade, after a downward trend since 1960. Precipitation was positively related to species richness, colonisation events, and cover, and negatively to disappearance events. Longer snow cover duration and rising temperatures were also related to increasing species numbers, but not to cover changes. The rapid biotic responses of Mediterranean alpine plants indicate a tight synchronisation with climate fluctuations, especially with water availability. Thus, it rather confirms concerns about biodiversity losses, if projections of increasing temperature in combination with decreasing precipitation hold true.
Hyperinsulinaemic–hypoglycaemic glucose clamps in human research: a systematic review of the literature
Authors:   on behalf of the Hypo-RESOLVE consortium, Fabricius Therese W. , Verhulst Clementine E. M. , Kristensen Peter L. , Tack Cees J. , McCrimmon Rory J. , Heller Simon , Evans Mark L. , Amiel Stephanie A. , Pieber Thomas R. , de Galan Bastiaan E. , Pedersen-Bjergaard Ulrik 
Published: February 2021

Abstract
Aims/hypothesis
The hyperinsulinaemic–hypoglycaemic glucose clamp technique has been developed and applied to assess effects of and responses to hypoglycaemia under standardised conditions. However, the degree to which the methodology of clamp studies is standardised is unclear. This systematic review examines how hyperinsulinaemic–hypoglycaemic clamps have been performed and elucidates potential important differences.

Methods
A literature search in PubMed and EMBASE was conducted. Articles in English published between 1980 and 2018, involving adults with or without diabetes, were included.

Results
A total of 383 articles were included. There was considerable variation in essential methodology of the hypoglycaemic clamp procedures, including the insulin dose used (49-fold difference between the lowest and the highest rate), the number of hypoglycaemic steps (range 1−6), the hypoglycaemic nadirs (range 2.0–4.3 mmol/l) and the duration (ranging from 5 to 660 min). Twenty-seven per cent of the articles reported whole blood glucose levels, most venous levels. In 70.8% of the studies, a dorsal hand vein was used for blood sampling, with some form of hand warming to arterialise venous blood in 78.8% of these. Key information was missing in 61.9% of the articles.

Conclusions/interpretation
Although the hyperinsulinaemic–hypoglycaemic clamp procedure is considered the gold standard to study experimental hypoglycaemia, a uniform standard with key elements on how to perform these experiments is lacking. Methodological differences should be considered when comparing results between hypoglycaemic clamp studies.

PROSPERO registration
This systematic review is registered in PROSPERO (CRD42019120083).

Graphical abstract
UNITY and Büchi automata
Authors: Hesselink Wim H. 
Published: February 2021

Abstract

UNITY is a model for concurrent specifications with a complete logic for proving progress properties of the form “
P
leads to
Q
”. UNITY is generalized to U-specifications by giving more freedom to specify the steps that are to be taken infinitely often. In particular, these steps can correspond to non-total relations. The generalization keeps the logic sound and complete. The paper exploits the generalization in two ways. Firstly, the logic remains sound when the specification is extended with hypotheses of the form “
F
leads to
G
”. As the paper shows, this can make the logic incomplete. The generalization is used to show that the logic remains complete, if the added hypotheses “
F
leads to
G
” satisfy “
F
unless
G
”. The main result extends the applicability and completeness of UNITY logic to proofs that a given concurrent program satisfies any given formula of LTL, linear temporal logic, without the next-operator which is omitted because it is sensitive to stuttering. For this purpose, the program, written as a UNITY program, is extended with a number of boolean variables. The proof method relies on implementing the LTL formula, i.e., restricting the specification in such a way that only those runs remain that satisfy the formula. This result is a variation of the classical construction of a Büchi automatonfor a given LTL formula that accepts precisely those runs that satisfy the formula.
Qualitative profiling of mono- and sesquiterpenols in aglycon libraries from Vitis vinifera L. Gewürztraminer using multidimensional gas chromatography–mass spectrometry
Authors: Könen Philipp P. , Stötzel Ines , Schwab Wilfried , Wüst Matthias 
Published: February 2021

AbstractIn grape berries (Vitis vinifera L.), sesquiterpenes are mainly accumulated as hydrocarbons in the epicuticular wax layer of grapes, whereas monoterpenes, which are predominantly present as alcohols, are glycosylated and are stored as glycosides in the vacuoles of grape berry cells. In this study, extensive analysis of grape berry hydrolysates by means of comprehensive two-dimensional gas chromatography–time-of-flight–mass spectrometry demonstrated that glycosylated sesquiterpene alcohols show very little structural diversity when compared to the sesquiterpene hydrocarbon fraction in the cuticle and are glycosylated to a rather low extent when compared to monoterpenols. Twenty-four enzymatically released terpenols were found in hydrolysates of the aromatic white wine variety Gewürztraminer (V. vinifera subsp. vinifera) after previous solid-phase extraction and headspace solid-phase microextraction. The detection of only three sesquiterpene alcohols, namely farnesol, nerolidol and drimenol, shows that most sesquiterpene hydrocarbons do not have a related hydroxylated structure in grapes. Nevertheless, the presence of the acyclic aglycone farnesol and nerolidol may be of importance for the wine aroma, since these structural isomers can be converted into numerous sesquiterpenes by nonenzymatic acid-catalyzed reactions during wine production. Grape-derived glycosidically bound sesquiterpene alcohols, therefore, represent, in addition to free sesquiterpene hydrocarbons, another pool of compounds that may influence the aroma profile of wines.
Frühe digitale Poesie
Authors: Bernhart Toni , Richter Sandra 
Published: February 2021

ZusammenfassungDie Idee, Poesie maschinell zu generieren, ist so alt wie die Maschinen selbst. Sie lässt sich seit dem Mittelalter beobachten und setzt sich fort bis in die Gegenwart, in der Storytelling-Experimente Algorithmen zur natürlichsprachigen Textgenerierung (NLG) nutzen. Die weltweit ersten Versuche, Poesie digital herzustellen, gelangen in den 1950er Jahren den Mathematikern Christopher Strachey (1916–1975) in Manchester und Theo Lutz (1932–2010) in Stuttgart. Durch zufallsmäßige Auswahl passfähiger Wörter und Sätze erzeugte Strachey 1952 auf einer Ferranti Mark I kurze Liebesbriefe. Dazu verwendete er das Programmierhandbuch von Alan Turing (1912–1954). Daneben schrieb Strachey Programme für das Dame-Spiel und zur computationellen Erzeugung von Musik. Lutz stellte 1959 mithilfe eines Programms im Freiburger Code auf einer Zuse Z 22 seine Stochastischen Texte her, wofür er Wortmaterial aus Franz Kafkas Roman Das Schloss (1926) verwendete und wobei er mit dem Philosophen Max Bense (1910–1990) und dem späteren Informatik-Pionier Rul Gunzenhäuser (1933–2018) kooperierte. Weil Lutz’ Arbeitsunterlagen nahezu vollständig erhalten und im Deutschen Literaturarchiv Marbach für die Forschung zugänglich sind, gilt Lutz als ein literatur- und informatikgeschichtlich bedeutsamer Vertreter früher digitaler Poesie, die lange Zeit fast nur in avantgardistischen Zirkeln diskutiert wurde und kaum den Weg in eine breitere Öffentlichkeit fand. Erst aktuelle Debatten um sogenannte Künstliche Intelligenz (KI) lenken wieder die Aufmerksamkeit auf diese frühen Experimente, die ein faszinierender Mosaikstein der Technik‑, Kultur- und Literaturgeschichte sind.
Effect of Exogenously Applied 24-Epibrassinolide and Brassinazole on Xylogenesis and Microdistribution of Cell Wall Polymers in Leucaena leucocephala (Lam) De Wit
Authors: Pramod S. , Anju M. , Rajesh H. , Thulaseedharan A. , Rao Karumanchi S. 
Published: February 2021

AbstractPlant growth regulators play a key role in cell wall structure and chemistry of woody plants. Understanding of these regulatory signals is important in advanced research on wood quality improvement in trees. The present study is aimed to investigate the influence of exogenous application of 24-epibrassinolide (EBR) and brassinosteroid inhibitor, brassinazole (BRZ) on wood formation and spatial distribution of cell wall polymers in the xylem tissue of Leucaena leucocephala using light and immuno electron microscopy methods. Brassinazole caused a decrease in cambial activity, xylem differentiation, length and width of fibres, vessel element width and radial extent of xylem suggesting brassinosteroid inhibition has a concomitant impact on cell elongation, expansion and secondary wall deposition. Histochemical studies of 24-epibrassinolide treated plants showed an increase in syringyl lignin content in the xylem cell walls. Fluorescence microscopy and transmission electron microscopy studies revealed the inhomogenous pattern of lignin distribution in the cell corners and middle lamellae region of BRZ treated plants. Immunolocalization studies using LM10 and LM 11 antibodies have shown a drastic change in the micro-distribution pattern of less substituted and highly substituted xylans in the xylem fibres of plants treated with EBR and BRZ. In conclusion, present study demonstrates an important role of brassinosteroid in plant development through regulating xylogenesis and cell wall chemistry in higher plants.
Umbilical cord blood CD34+ cells administration improved neurobehavioral status and alleviated brain injury in a mouse model of cerebral palsy
Authors: Chang Yanqun , Lin Shouheng , Li Yongsheng , Liu Song , Ma Tianbao , Wei Wei 
Published: February 2021

Abstract
Purpose
Cerebral palsy (CP) is the most common neuromuscular disease in children, and currently, there is no cure. Several studies have reported the benefits of umbilical cord blood (UCB) cell treatment for CP. However, these studies either examined the effects of UCB cell fraction with a short experimental period or used neonatal rat models for a long-term study which displayed an insufficient immunological reaction and clearance of human stem cells. Here, we developed a CP model by hypoxia-ischemic injury (HI) using immunodeficient mice and examined the effects of human UCB CD34+ hematopoietic stem cells (HSCs) on CP therapy over a period of 8 weeks.

Methods
Sixty postnatal day-9 (P9) mouse pups were randomly divided into 4 groups (n = 15/group) as follows: (1) sham operation (control group), (2) HI-induced CP model, (3) CP model with CD34+ HSC transplantation, and (4) CP model with CD34- cell transplantation. Eight weeks after insult, the sensorimotor performance was analyzed by rotarod treadmill, gait dynamic, and open field assays. The pathological changes in brain tissue of mice were determined by HE staining, Nissl staining, and MBP immunohistochemistry of the hippocampus in the mice.

Results
HI brain injury in mice pups resulted in significant behavioral deficits and loss of neurons. Both CD34+ HSCs and CD34- cells improved the neurobehavioral statuses and alleviated the pathological brain injury. In comparison with CD34- cells, the CD34+ HSC compartments were more effective.

Conclusion
These findings indicate that CD34+ HSC transplantation was neuroprotective in neonatal mice and could be an effective therapy for CP.
An architectonic type principle in the development of laminar patterns of cortico-cortical connections
Authors: Beul Sarah F. , Goulas Alexandros , Hilgetag Claus C. 
Published: February 2021

AbstractStructural connections between cortical areas form an intricate network with a high degree of specificity. Many aspects of this complex network organization in the adult mammalian cortex are captured by an architectonic type principle, which relates structural connections to the architectonic differentiation of brain regions. In particular, the laminar patterns of projection origins are a prominent feature of structural connections that varies in a graded manner with the relative architectonic differentiation of connected areas in the adult brain. Here we show that the architectonic type principle is already apparent for the laminar origins of cortico-cortical projections in the immature cortex of the macaque monkey. We find that prenatal and neonatal laminar patterns correlate with cortical architectonic differentiation, and that the relation of laminar patterns to architectonic differences between connected areas is not substantially altered by the complete loss of visual input. Moreover, we find that the degree of change in laminar patterns that projections undergo during development varies in proportion to the relative architectonic differentiation of the connected areas. Hence, it appears that initial biases in laminar projection patterns become progressively strengthened by later developmental processes. These findings suggest that early neurogenetic processes during the formation of the brain are sufficient to establish the characteristic laminar projection patterns. This conclusion is in line with previously suggested mechanistic explanations underlying the emergence of the architectonic type principle and provides further constraints for exploring the fundamental factors that shape structural connectivity in the mammalian brain.
Photosynthetically Controlled Spirulina, but Not Solar Spirulina, Inhibits TNF-α Secretion: Potential Implications for COVID-19-Related Cytokine Storm Therapy
Authors: Tzachor Asaf , Rozen Or , Khatib Soliman , Jensen Sophie , Avni Dorit 
Published: February 2021

AbstractAn array of infections, including the novel coronavirus (SARS-CoV-2), trigger macrophage activation syndrome (MAS) and subsequentlyhypercytokinemia, commonly referred to as a cytokine storm (CS). It is postulated that CS is mainly responsible for critical COVID-19 cases, including acute respiratory distress syndrome (ARDS). Recognizing the therapeutic potential of Spirulina blue-green algae (Arthrospira platensis), in this in vitro stimulation study, LPS-activated macrophages and monocytes were treated with aqueous extracts of Spirulina, cultivated in either natural or controlled light conditions. We report that an extract of photosynthetically controlled Spirulina (LED Spirulina), at a concentration of 0.1 µg/mL, decreases macrophage and monocyte-induced TNF-α secretion levels by over 70% and 40%, respectively. We propose prompt in vivo studies in animal models and human subjects to determine the putative effectiveness of a natural, algae-based treatment for viral CS and ARDS, and explore the potential of a novel anti-TNF-α therapy.Graphical abstract
Prevalence of high-riding vertebral arteries and narrow C2 pedicles among Central-European population: a computed tomography-based study
Authors: Klepinowski Tomasz , Żyłka Natalia , Pala Bartłomiej , Poncyljusz Wojciech , Sagan Leszek 
Published: February 2021

AbstractHigh-riding vertebral artery (HRVA) and narrow C2 pedicles (C2P) pose a great risk of injuring the vessel during C2 pedicle or transarticular screw placement. Recent meta-analysis revealed a paucity of European studies regarding measurements and prevalence of these anatomical variants. Three hundred eighty-three consecutive cervical spine CT scans with 766 potential screw insertion sites were analyzed independently by two trained observers. C2 internal height (C2InH), C2 isthmus height (C2IsH), and C2P width were measured. Kappa statistics for inter- and intraobserver reliability as well as for inter-software agreement were calculated. HRVA was defined as C2IsH of ≤ 5 mm and/or C2InH of ≤ 2 mm. Narrow C2P was defined as C2P width ≤ 4 mm. STROBE checklist was followed. At least 1 HRVA was found in 25,3% (95% CI 21,1–29,8) of patients (16,7% of potential sites). At least 1 narrow C2P was seen in 36,8% (95% CI 32,1–41,7) of patients (23,8% of potential sites). Among those with HRVA, unilateral HRVA was present in 68,0% (95% CI 58,4–77,0), whereas bilateral HRVA in 32,0% (95% CI 23,0–41,6). No difference in terms of laterality (right or left) was seen neither for HRVA nor narrow C2P. Significant differences were found between females and males for all measurements. Each parameter showed either good or excellent inter- or intraobserver, and inter-software agreement coefficients. HRVA and narrow C2P are common findings in Central-European population and should be appreciated at the planning stage before craniocervical instrumentation. Measurements can be consistently reproduced by various observers at varying intervals using different software.
Cost-effectiveness of the latent tuberculosis screening program for migrants in Stockholm Region
Authors: Shedrawy Jad , Deogan Charlotte , Öhd Joanna Nederby , Hergens Maria-Pia , Bruchfeld Judith , Jonsson Jerker , Siroka Andrew , Lönnroth Knut 
Published: February 2021

AbstractIntroductionThe majority of tuberculosis (TB) cases in Sweden occur among migrants from endemic countries through activation of latent tuberculosis infection (LTBI). Sweden has LTBI-screening policies for migrants that have not been previously evaluated. This study aimed to assess the cost-effectiveness of the current screening strategy in Stockholm.MethodsA Markov model was developed to predict the costs and effects of the current LTBI-screening program compared to a scenario of no LTBI screening over a 50-year time horizon. Epidemiological and cost data were obtained from local sources when available. The primary outcomes were incremental cost-effectiveness ratio (ICER) in terms of societal cost per quality-adjusted life year (QALY).ResultsScreening migrants in the age group 13–19 years had the lowest ICER, 300,082 Swedish Kronor (SEK)/QALY, which is considered cost-effective in Sweden. In the age group 20–34, ICER was 714,527 SEK/QALY (moderately cost-effectives) and in all age groups above 34 ICERs were above 1,000,000 SEK/QALY (not cost-effective). ICER decreased with increasing TB incidence in country of origin.ConclusionScreening is cost-effective for young cohorts, mainly between 13 and 19, while cost-effectiveness in age group 20–34 years could be enhanced by focusing on migrants from highest incidence countries and/or by increasing the LTBI treatment initiation rate. Screening is not cost-effective in older cohorts regardless of the country of origin.
The effect of navigation method and visual display on distance perception in a large-scale virtual building
Authors: Li Hengshan , Mavros Panagiotis , Krukar Jakub , Hölscher Christoph 
Published: February 2021

AbstractImmersive virtual reality (VR) technology has become a popular method for fundamental and applied spatial cognition research. One challenge researchers face is emulating walking in a large-scale virtual space although the user is in fact in a small physical space. To address this, a variety of movement interfaces in VR have been proposed, from traditional joysticks to teleportation and omnidirectional treadmills. These movement methods tap into different mental processes of spatial learning during navigation, but their impacts on distance perception remain unclear. In this paper, we investigated the role of visual display, proprioception, and optic flow on distance perception in a large-scale building by manipulating four different movement methods. Eighty participants either walked in a real building, or moved through its virtual replica using one of three movement methods: VR-treadmill, VR-touchpad, and VR-teleportation. Results revealed that, first, visual display played a major role in both perceived and traversed distance estimates but did not impact environmental distance estimates. Second, proprioception and optic flow did not impact the overall accuracy of distance perception, but having only an intermittent optic flow (in the VR-teleportation movement method) impaired the precision of traversed distance estimates. In conclusion, movement method plays a significant role in distance perception but does not impact the configurational knowledge learned in a large-scale real and virtual building, and the VR-touchpad movement method provides an effective interface for navigation in VR.
Who is the African Farmer? The Importance of Actor Representations in the Debate About Biotechnology Crops in Africa
Authors: Beumer Koen , Swart Jac. A. A. 
Published: February 2021

AbstractThe discussion about the impact of agricultural biotechnology on Africa is deeply divided and contains widely diverging claims about the impact of biotechnology on African farmers. Building upon literature on the ‘good farmer’ that highlights that farmers identities are an important factor in explaining the success or failure of agricultural change, we argue that the identity of the farmer is an undervalued yet crucial aspect for understanding the debate about the impact of agricultural biotechnology on African farmers. In this article we therefore investigate what farmers’ identities are implicated in the arguments about the impact of biotechnology on African farmers. We aim to identify the main fault lines in different accounts of the African biotechnology farmer by analysing the identities ascribed to them in two prominent cases of controversy: the debates at the 2002 World Summit on Sustainable Development in Johannesburg and the discussion about the impact of biotechnology on smallholder farmers in the Makhathini flats in KwaZulu Natal, South Africa. Our findings demonstrate that arguments about biotechnology are informed by diverging conceptions of who the African farmer is, what is important for the African farmer, and what role the African farmer has in relation to agricultural biotechnology. These findings remain relevant for current discussions on gene editing technologies like CRISPR-Cas. Openly discussing these different views on the identity of smallholder farmers is crucial for moving forward in the biotechnology controversy and can inform future attempts to elicit the farmer’s voice.