bluuebunny/crossref_metadata_2025 huggingface dataset:
Contrasting impacts of a novel specialist vector on multihost viral pathogen epidemiology in wild and managed bees
Authors: Manley Robyn , Temperton Ben , Boots Mike , Wilfert Lena
Published: December 2019

Typically, pathogens infect multiple host species. Such multihost pathogens can show considerable variation in their degree of infection and transmission specificity, which has important implications for potential disease emergence. Transmission of multihost pathogens can be driven by key host species and changes in such transmission networks can lead to disease emergence. We study two viruses that show contrasting patterns of prevalence and specificity in managed honeybees and wild bumblebees, black queen cell virus (BQCV) and slow bee paralysis virus (SBPV), in the context of the novel transmission route provided by the virus‐vectoring Varroa destructor. Our key result is that viral communities and RNA virus genetic variation are structured by location, not host species or V. destructor presence. Interspecific transmission is pervasive with the same viral variants circulating between pollinator hosts in each location; yet, we found virus‐specific host differences in prevalence and viral load. Importantly, V. destructor presence increases the prevalence in honeybees and, indirectly, in wild bumblebees, but in contrast to its impact on deformed wing virus (DWV), BQCV and SBPV viral loads are not increased by Varroa presence, and do not show genetic evidence of recent emergence. Effective control of Varroa in managed honeybee colonies is necessary to mitigate further disease emergence, and alleviate disease pressure on our vital wild bee populations. More generally, our results highlight the over‐riding importance of geographical location to the epidemiological outcome despite the complexity of multihost‐parasite interactions.
Differences in foot skin microbiomes between patients with type 2 diabetes and healthy individuals
Authors: Han Song Hee , Lee Ji Su , Song Kee‐Ho , Choe Yong Beom , Ahn Kyu Joong , Lee Yang Won
Published: December 2019

Impaired immunity and changes in the microenvironment in patients with diabetes might influence the composition of the cutaneous microbiome. However, data on the cutaneous microbiome of these patients are scarce. This study compared the fungal and bacterial components of the skin microbiome between patients with type 2 diabetes mellitus (DM) and healthy individuals. We obtained skin swab samples from the plantar forefoot of 17 patients with DM and 18 healthy individuals to conduct a cross‐sectional study. The samples were profiled with culture‐independent sequencing of the V3 to V4 regions of the bacterial 16S rRNA gene and the fungal ITS2 region, followed by direct DNA extraction and molecular polymerase chain reaction (PCR). We observed a differential cutaneous microbiome, especially for fungi, in patients with type 2 diabetes compared to that in healthy controls. Trichophyton rubrum was more abundant in DM samples. The Shannon diversity index for fungi was lower in the DM patients. Principal coordinate analysis plots and permutational multivariate analysis of variance (PERMANOVA) tests based on Bray‐Curtis distances between samples supported the association of the fungal microbiome with DM at the species level. The results suggest that clinicians should pay attention to both fungi and bacteria and provide appropriate prevention and therapeutic strategies for diabetic cutaneous complications including diabetic foot ulcers. These data also contribute to future research associated with diabetes and cutaneous microbiomes.
In search of the nation in Fiume: Irredentism, cultural nationalism, borderlands
Authors: van Hout Milou
Published: December 2019

Irredentism is a crucial, yet understudied phenomenon of nationalism. Most scholars emphasise how irredentist thinking and practices function as a geopolitical instrument for inter‐state formation, resulting in radical nationalism. This article sheds light instead on the cultural preoccupations underlying irredentist discourses. It focusses on irredentist claims on the Adriatic city of Fiume (Rijeka) among Italian nationalists in the 19th and 20th centuries, emphasising how they were driven by cultural imaginaries of a spiritual borderland for the nation. These imaginaries continued to inform irredentist arguments during the phase of political mobilisation. This sheds light on contemporary European politics, in which irredentist imaginaries are once again shaping nationalist discourses.
Contrasting plant adaptation strategies to latitude in the native and invasive range of Spartina alterniflora
Authors: Liu Wenwen , Zhang Yihui , Chen Xincong , Maung‐Douglass Keith , Strong Donald R. , Pennings Steven C.
Published: December 2019

Biological invasions offer model systems of contemporary evolution. We examined trait differences and evolution across geographic clines among continents of the intertidal grass Spartina alterniflora within its invasive and native ranges.

We sampled vegetative and reproductive traits in the field at 20 sites over 20° latitude in China (invasive range) and 28 sites over 17° in the US (native range). We grew both Chinese and US plants in a glasshouse common garden for 3 yr.

Chinese plants were c. 15% taller, c. 10% denser, and set up to four times more seed than US plants in both the field and common garden. The common garden experiments showed a striking genetic cline of seven‐fold greater seed set at higher latitudes in the introduced but not the native range. By contrast, there was a slight genetic cline in some vegetative traits in the native but not the introduced range.

Our results are consistent with others showing that introduced plants can evolve rapidly in the new range. S. alterniflora has evolved different trait clines in the native and introduced ranges, showing the importance of phenotypic plasticity and genetic control of change during the invasion process.
Water use strategy affects avoidance of ozone stress by stomatal closure in Mediterranean trees—A modelling analysis
Authors: Hoshika Yasutomo , Fares Silvano , Pellegrini Elisa , Conte Adriano , Paoletti Elena
Published: December 2019

Both ozone (O3) and drought can limit carbon fixation by forest trees. To cope with drought stress, plants have isohydric or anisohydric water use strategies. Ozone enters plant tissues through stomata. Therefore, stomatal closure can be interpreted as avoidance to O3 stress. Here, we applied an optimization model of stomata involving water, CO2, and O3 flux to test whether isohydric and anisohydric strategies may affect avoidance of O3 stress by stomatal closure in four Mediterranean tree species during drought. The data suggest that stomatal closure represents a response to avoid damage to the photosynthetic mechanisms under elevated O3 depending on plant water use strategy. Under high‐O3 and well‐watered conditions, isohydric species limited O3 fluxes by stomatal closure, whereas anisohydric species activated a tolerance response and did not actively close stomata. Under both O3 and drought stress, however, anisohydric species enhanced the capacity of avoidance by closing stomata to cope with the severe oxidative stress. In the late growing season, regardless of the water use strategy, the efficiency of O3 stress avoidance decreased with leaf ageing. As a result, carbon assimilation rate was decreased by O3 while stomata did not close enough to limit transpirational water losses.
Growth characterization in a cohort of renal allograft recipients
Authors: Prada Rico Mayerly , Fernandez Hernandez Monica , Castellanos Marcela C. , Prado Agredo Olga L. , Pedraza Carvajal Alejandra , González Chaparro Luz E. , Gastelbondo Amaya Ricardo , Benavides Viveros Carlos A.
Published: December 2019

Introduction

Growth retardation is a common problem in children with CKD. This study aims to describe growth, prevalence of short stature before RTx, catch‐up growth after RTx, and associated factors.

Methods

We retrospectively reviewed 74 renal allograft recipients who underwent RTx at Fundación Cardioinfantil, Colombia, between January 2008 and September 2016 with follow‐up for 2 years afterwards. Pre‐RTx Height_SDS and demographic characteristics were compared between children with normal and short stature. Post‐RTx Height_SDS at 1 and 2 years post‐RTx and FAH, when available, were retrieved. Children were classified into catch‐up growth and no catch‐up growth groups depending on whether or not Height_SDS increased ≥0.5 per year within the first 2 years post‐RTx. Possible associated factors were compared.

Results

Seventy‐four patients were included. Mean age at RTx was 11 ± 4.0 years, and 43.2% (32/74) were females. Mean Height_SDS for the entire study population at pre‐RTx was −2.8 ± 1.5. Before RTx, 68.9% (51/74) had short stature, and 44.6% (33/74) had severe short stature. 37.2% presented catch‐up growth post‐RTx. Time on dialysis was associated with short pre‐RTx stature (OR 1.66; 95% CI [1.15‐2.39];P = .006) and catch‐up growth (OR 2.15; 95% CI [1.15‐3.99];P = .016). 44.59% (33/74) reached FAH, and 48.4% (16/33) presented short FAH.

Conclusions

Growth continues to be suboptimal after RTx. Given that pre‐RTx height is a significantly associated factor, it is important to plan early interventions in terms of growth improvement in these children.
Impact of a community‐based approach to patient engagement in rural, low‐income adults with type 2 diabetes
Authors: Glenn Lynn E. , Nichols Michelle , Enriquez Maithe , Jenkins Carolyn
Published: December 2019

Objective

This secondary analysis examined the relationships between Patient Activation Measure (PAM) scores, use of health services, and HgA1C.

Design

A feasibility study was conducted for a community‐based intervention for high‐risk adults with uncontrolled diabetes. Data were collected at baseline and monthly, including PAM and modified Diabetes Self‐Management Assessment Report Tool.

Intervention

Participants (n = 58) were randomized to a 3‐month nurse (RN) telephone management or community health worker (CHW) in‐home intervention, focusing on medication adherence, timely follow‐up, diabetes self‐management coaching, and linkage to resources.

Results

Sample was mostly female (73%), African‐American (90%), low income (75%), high school education or less (80%), and mean age of 59 years. A positive association between PAM score and self‐reported diabetes care recommendations was found (r = .356, p = .014) and significant correlation between baseline PAM score and HgA1C levels (r = −.306, p = .029). A paired samples t test showed statistically significant increases in PAM scores in the CHW intervention group (mean increase +8.5, CI [+2.49 to +14.65]); baseline (M = 60.31, SD = 13.3) to end of study ([M = 68.89, SD = 16.39], t(22) = 2.924, p = .008 [two‐tailed]).

Conclusion

A community‐based approach to diabetes management demonstrated a positive effect on patient activation. Although disparities in health care access among rural, low‐income populations exist, community‐based interventions show potential for improving patient engagement in diabetes management and recommended health services.
A call to act: RN volunteers needed in their communities
Authors: LoGrippo Maria Torchia , Brienza‐Arcilla Diane , Vaid Raoji Nina , Polakowski Jennifer
Published: December 2019

Objective

Recognizing registered nurses (RNs) as valued, trusted professionals to lead and advocate for healthier communities (Pittman, 2019), the New Jersey Action Coalition (NJAC) developed a model designed to match RN volunteers to community projects.

Design

Using a descriptive study design, researchers examined the numbers of RN volunteers and projects across 21 counties in NJ from 2016 to 2018.

Sample

The sample consisted of the numbers of volunteers and projects from every county retrieved from the NJAC's website.

Measurements

In addition to the NJAC data, researchers examined the percentage of RNs living in each county as well as data from County Health Rankings & Roadmaps© (University of Wisconsin Population Health Institute, 2019). The counties were divided into three groups: high, moderate, and low overall health counties.

Results

After 2 years of implementing the NJAC model, the data revealed that, at minimum, there was one RN coach per county in the high overall health counties group. In the lower overall health counties group, there were fewer community projects, less RN coaches, and volunteers.

Conclusion

Engaging RN volunteers requires raising awareness of the needs of the community and the ways in which a RN can take action to promote public health and health equity.
Water‐soluble carbohydrates in Patzkea paniculata (L.): a plant strategy to tolerate snowpack reduction and spring drought in subalpine grasslands
Authors: Bernard L. , Decau M.‐L. , Morvan‐Bertrand A. , Lavorel S. , Clément J.‐C.
Published: December 2019

In subalpine grasslands of the central French Alps, cessation of traditional mowing promotes dominance of Patzkea paniculata (L.) G.H.Loos (Poaceae) tussocks, with high biomass but low fodder quality. Mowing limits P. paniculata abundance through the depletion of its water‐soluble carbohydrate (WSC) reserves, which sustain early spring growth initiation. However, the effectiveness of mowing effects is modulated by grassland functional composition, fertilization and climate change, as WSC compounds, and notably fructans, support plant physiological responses to climate stresses such as drought or frost.

To characterize the mechanisms underpinning the control of P. paniculata under global change, we tested the effects of climate manipulation (combined snow removal and drought) and management (cutting and fertilization) alone or in combination on P. paniculata WSC storage in assembled grassland communities of varying functional composition.

Management and climate treatments individually decreased seasonal fructan storage, with neither additive nor synergic effects between them, primarily due to the dominance of management over climate effects. Fructan amounts were higher in individuals growing in unmanaged exploitative communities compared to unmanaged conservative communities, regardless of climate treatments, but management overrode these differences.

Our findings suggest that reduction by combined snow removal and drought of P. paniculata carbon allocation to WSC storage may similarly limit its dominance to that in current mowing practices.
On the Acoustics of Policy Learning: Can Co‐Participation in Policy Forums Break Up Echo Chambers?
Authors: Malkamäki Arttu , Wagner Paul M. , Brockhaus Maria , Toppinen Anne , Ylä‐Anttila Tuomas
Published: December 2019

Overcoming common‐pool resource dilemmas requires learning across different sectors of society. However, policy actors frequently entrench themselves in so‐called echo chambers by preferring to rely on information from those whose policy beliefs resemble their own. Policy forums can reduce the limiting effects of echo chambers by encouraging actors with diverse knowledge bases to exchange information and learn from one another. This paper applies exponential random graph models to network data from the South African tree plantation policy domain to investigate how belief homophily, reputational influence, and forum co‐participation shape information exchange behavior. Results show that echo chambers are important determinants of information exchange ties and that reputational influence is likely to "deepen" the echo. Results also show that the more forums that a pair of actors co‐participate in, the more likely they are to exchange information. This applies to information exchange generally, as well as information exchange with trusted partners. Findings indicate that forums enable both cognitive learning (as knowledge gains) and relational learning (as improved relations). Nonetheless, when echo chambers are strong, and many forums are polarized, then forum co‐participation may not break up echo chambers.
Premature centromere division (PCD) identified in a hucul mare with reproductive difficulties
Authors: Witarski Wojciech , Kij Barbara , Nowak Agnieszka , Bugno‐Poniewierska Monika
Published: December 2019

A hucul mare with reproductive abnormalities was examined during karyotype analysis. The karyotype was analysed based on evaluation of 860 metaphase plates in chromosome preparations. The use of fluorescence in situ hybridization (FISH) with an X chromosome painting probe showed premature X chromosome separation in 9.5% cases of examined chromosome spreads. In this report, we present the first identify premature centromere division (PCD) as a possible cause of abnormal X chromosome morphology in horses and as a probable cause of reproductive difficulties.
Recreational football is medicine against non‐communicable diseases: A systematic review
Authors: Sarmento Hugo , Manuel Clemente Filipe , Marques Adilson , Milanovic Zoran , David Harper Liam , Figueiredo António
Published: December 2019

The purpose of this research was to conduct a systematic review of published articles related to the effect of recreational football on non‐communicable diseases.

A systematic review of Web of Science, SPORTDiscus, MEDLINE, and PubMed databases was performed according to PRISMA guidelines. Only empirical studies were included. There were no restrictions on the types of study design eligible for inclusion. The primary outcome measures result from the potential effects of recreational football on non‐communicable diseases (eg, blood pressure, bone density, LDL cholesterol, and fat mass).

A total of 44 articles met the inclusion criteria and were included. Recreational football is shown to: (a) decrease blood pressure and resting heart rate, improve cardiac structure and functioning, as well as increase maximal oxygen uptake in both sexes; (b) reduce cholesterol and triglycerides levels, increase insulin sensitivity, and have a positive impact on glycemic control; (c) improve bone mineralization, increase both bone mineral density and content, as well as acting as a stimulus for osteogenesis; and (d) be clearly beneficial for bone health, while slightly beneficial for body composition, muscle strength, and maximal oxygen uptake in adults with prostate cancer.

The present systematic review demonstrated the benefits of recreational football practice on non‐communicable diseases related to cardiovascular and bone health, body composition, type 2 diabetes, and prostate cancer. The effectiveness of recreational football on the aforementioned diseases may be related to age and gender; however, further research is required.
Many dimensions of Asian American pan‐ethnicity
Authors: Lee Jess
Published: December 2019

Asian Americans as a group consist of over 20 national origin groups with distinctive ethnicity, language, religion, cultural practices, immigration history, and perceptions of life in the United States. While “Asian American” has been interchangeably used to refer to both racial and pan‐ethnic grouping of individuals of Asian heritage, the exact meaning of the term varies contextually by one's ethnicity, experiences, and other social, structural, and cultural characteristics. In this article, I investigate three distinctive ways in which Asian Americans understand and enact upon their pan‐ethnicity: (a) as a political instrument, (b) as a social group identity, and (c) as a path of integration into the mainstream society. Then, I briefly discuss implications of pan‐ethnicity for Asian Americans, before turning to the discussion of ways in which future research could further investigate the complexities of pan‐ethnicity. I conclude by attempting to provide a nuanced definition of Asian American pan‐ethnicity based on the literature reviewed in this article.
Religion Imagined: The Conceptual Substructures of American Religious Understandings
Authors: Rotolo Michael
Published: December 2019

Sociologists have increasingly drawn on the cognitive sciences to better theorize how culture works. While this shift has improved understandings of the distinct qualities of practical and discursive modes of cognition, limited consideration has been given to the cognitive structures that scaffold cultural understandings. This article theorizes the influence of “image schemas” in structuring cultural understandings beneath the level of conscious awareness. After outlining how image schemas can be identified in interviews, I reconstruct how 50 religious Americans unconsciously “imagine” religion's role in their lives. Focusing on the implicit rather than respondents' explicit discourse, I identify five image schemas that structure Americans' religious understandings. Although respondents' understandings often appear incoherent and inconsistent at the level of explicit discourse, I show that they are coherent and consistent at the level of implicit image schemas. I then use factor analysis to identify patterns in these implicit understandings across social divisions. I conclude by discussing the promise of image schema analysis for improving studies of religion and other areas, as well as for theorizing how culture works.
Two combinatorial patterns of telomere histone marks in plants with canonical and non‐canonical telomere repeats
Authors: Adamusová Kateřina , Khosravi Solmaz , Fujimoto Satoru , Houben Andreas , Matsunaga Sachihiro , Fajkus Jiří , Fojtová Miloslava
Published: December 2019

Telomeres, nucleoprotein structures at the ends of linear eukaryotic chromosomes, are crucial for the maintenance of genome integrity. In most plants, telomeres consist of conserved tandem repeat units comprising the TTTAGGG motif. Recently, non‐canonical telomeres were described in several plants and plant taxons, including the carnivorous plant Genlisea hispidula (TTCAGG/TTTCAGG), the genus Cestrum (Solanaceae; TTTTTTAGGG), and plants from the Asparagales order with either a vertebrate‐type telomere repeat TTAGGG or Allium genus‐specific CTCGGTTATGGG repeat. We analyzed epigenetic modifications of telomeric histones in plants with canonical and non‐canonical telomeres, and further in telomeric chromatin captured from leaves of Nicotiana benthamiana transiently transformed by telomere CRISPR‐dCas9‐eGFP, and of Arabidopsis thaliana stably transformed with TALE_telo C‐3×GFP. Two combinatorial patterns of telomeric histone modifications were identified: (i) an Arabidopsis‐like pattern (A. thaliana, G. hispidula, Genlisea nigrocaulis, Allium cepa, Narcissus pseudonarcissus, Petunia hybrida, Solanum tuberosum, Solanum lycopersicum) with telomeric histones decorated predominantly by H3K9me2; (ii) a tobacco‐like pattern (Nicotiana tabacum, N. benthamiana, C. elegans) with a strong H3K27me3 signal. Our data suggest that epigenetic modifications of plant telomere‐associated histones are related neither to the sequence of the telomere motif nor to the lengths of the telomeres. Nor the phylogenetic position of the species plays the role; representatives of the Solanaceae family are included in both groups. As both patterns of histone marks are compatible with fully functional telomeres in respective plants, we conclude that the described specific differences in histone marks are not critical for telomere functions.
Power Generation Using Kites in a GroundGen Airborne Wind Energy System: A Numerical Study
Authors: Nejad Alireza Mahdavi , Tryggvason Gretar
Published: December 2019

A computational model of a massless kite that produces power in an airborne wind energy (AWE) system is presented. AWE systems use tethered kites at high altitudes to extract energy from the wind and are being considered as an alternative to wind turbines since the kites can move in high-speed cross-wind motions over large swept areas to increase power production. In our model, the kite completes successive power-retraction cycles where the kite angle of attack is altered as required to vary the resultant aerodynamic forces on the kite. The flow field is found in a two-dimensional domain near the flexible kite by solving the full Navier–Stokes equations using an Eulerian grid together with a Lagrangian representation of the kite. The flow solver is a finite volume projection method using a non-uniform mesh on a staggered grid and corrector–predictor technique to ensure a second-order accuracy in time. The two-dimensional kite shape is modeled as a slightly cambered immersed boundary that moves with the flow. The flexible kite is modeled with a set of linear springs following Hooke’s law. The unstretched length of each elastic tether at a given time step is controlled using periodic triangular wave shapes to achieve the required power-retraction phases. A study was conducted in which the wave shape amplitude, frequency, and phase (between two tethers) were adjusted to achieve a suitably high net power output. The results are in good agreement with predictions for Loyd’s simple kite in two-dimensional motion. Aerodynamic coefficients for the kite, tether tensions, tether reel-out and reel-in speeds, and the vorticity fields in the kite wake are also determined.
Design and Analysis of a Valveless Impedance Pump for a Direct Sodium Borohydride–Hydrogen Peroxide Fuel Cell
Authors: Yang A. S. , Tseng J. W. , Wen C. Y. , Zhang H.
Published: December 2019

A valveless impedance pump is designed and applied for the first time to supply the liquid fuels for a direct sodium borohydride–hydrogen peroxide fuel cell (DBHPFC). This valveless pump consists of an amber latex rubber tube, which is connected at both ends to rigid stainless-steel tubes of different acoustic impedance, and a simple actuation mechanism with a small direct control (DC) motor and a cam combined. The cam is activated by the motor and periodically compresses the elastic tube at a position asymmetrical from the tube ends. The traveling waves emitted from the compression combine with the reflected waves at the impedance-mismatched rubber tube/stainless-steel tube interfaces. The resulting wave interference creates a pressure gradient and generates a net flow. When connected to a DBHPFC with an active area of 25 cm2, the pump can deliver the fuel at a maximum pumping rate of 30 ml/min, resulting in corresponding DBHPFC maximum power and a current of 13.0 W and 25.5 A, respectively. The specific power, volumetric power density, and back work ratio of the DBHPFC with this pumping method have been proven superior to those of the other pumping configuration with peristaltic pumps. This valveless impedance pump is mechanically simply and less susceptible to corrosion, and it can reduce the volume and weight of fuel cell systems to a measurable extent. The experimental results demonstrate the feasibility of the device for practical DBHPFC applications.
Experimental Study on Flow-Induced Motions (FIM) of a Floating Offshore Wind Turbine Semi-Submersible Type (OC4 Phase II Floater)
Authors: Gonçalves Rodolfo T. , Chame Maria E. F. , Silva Leandro S. P. , Koop Arjen , Hirabayashi Shinichiro , Suzuki Hideyuki
Published: December 2019

Flow-Induced Motions (FIM) is an issue for multi-column platforms, and the phenomenon can decrease the fatigue life of the mooring, riser, and cable systems. In the past, FIM was studied mainly for platforms installed in deep waters. The new concepts of Floating Offshore Wind Turbines (FOWT) have multi-column design and may therefore observe FIM. However, FOWTs have been installed in shallow water and, in this case, the FIM remains insufficiently investigated. To address this issue, FIM model tests were performed for the – Semisubmersible (SS) Floating System design developed for the DeepCwind project (OC4 Phase II). The goal of this paper is to investigate the presence of FIM for this type of system to show the importance of FIM in the design of FOWT. Three different incidence angles of the current were tested, namely 0, 90 and 180 degrees. For each heading, thirty reduced velocities were tested. The results showed amplitudes in the transverse direction of around 70% of the diameter of the platform column, which is similar to the ones observed for the deep-draft (DD) SS with circular columns and larger than for the platforms with square columns. The results showed that FIM was present for this specific FOWT SS investigated and that it may thus be essential to consider when designing the mooring system, as an increment in the total cost of the platform may make the system economically unfeasible. When extrapolating the results for the full-scale configuration, the FIM synchronization occurred for current velocities from 0.5m/s up to 1.2m/s, and the maximum nondimensional nominal amplitudes for the motions in the transverse direction reached 70% of the external column diameter.
Large Aeroelastic Model of a Floating Offshore Wind Turbine: Mechanical and Mechatronics Design
Authors: Muggiasca Sara , Fontanella Alessandro , Taruffi Federico , Giberti Hermes , Facchinetti Alan , Belloli Marco , Bollati Marco
Published: December 2019

This paper deals with the mechatronic design of a large-scale wind turbine model (outdoor scaled prototype) based on the DTU 10MW. This is going to be integrated in the model of a multi-purpose floating structure to be deployed at the Natural Ocean Engineering Laboratory (NOEL) in Reggio Calabria (Italy). The floating wind turbine model is the downscaling of the full-scale structure designed within the EU H2020 Blue Growth Farm project. The structural design of the scaled wind turbine is presented, starting from the aeroelastic and aerodynamic design carried out in a previous work.
A Consistent Structural Damping Model for Integrated and Superelement Modelling of Offshore Wind Turbine Support Structures in Wind Turbine Design Software Bladed
Authors: Collier William
Published: December 2019

In aero-elastic simulation of offshore wind turbines, the support structure can be modelled using an “integrated” approach, where the jacket and tower and modelled explicitly as one structural body, or a “superelement” approach, where the jacket part of the support structure is included as a superelement. For integrated modelling, vibration mode shapes are calculated for the whole support structure. For a superelement approach, separate mode shapes are defined for superelement and the tower. The different modal basis makes it difficult to align the structural damping definition for the two approaches, meaning that manual tuning of the modal damping ratios has previously been necessary to achieve equivalent damping on the whole support structure for the two approaches. To provide a consistent damping approach, it is proposed to specify modal damping ratios or Rayleigh damping on a modal basis which is common to the two approaches: the support structure natural mode shapes. When damping is specified on the natural modes of the support structure, equivalent support structure damping is observed for superelement and integrated modelling approaches. This allows the target support structure damping ratios to be achieved easily and also facilitates studies to compare the superelement and integrated modelling approaches.
Effects of Variations on the Experimental Set-Up on the Motion Response of a Floating Wind Semisubmersible (OC4 Type)
Authors: Gueydon Sebastien
Published: December 2019

With their light weights, small components like braces and heave plates and steady trim angle caused by the wind loads acting on the rotor, semisubmersible foundations used as support platform for wind turbines exhibit a complex behaviour where viscous loading play an important role. The work done by the Offshore Code Comparison Collaboration Continued with Correlation (OC5) project has shown that standard engineering tools were not always able to predict accurately the motions of the DeepCwind semisubmersible that were measured in a basin. The correct amplitude of the motions at the natural periods of this system appeared to be difficult to obtain with simulations (especially the low frequency surge, and the pitch resonant motion). In view of the complexity of the system, it was not possible to clearly identify the causes of the differences between the simulations and the model-test results. A follow-on validation campaign was therefore performed at the Maritime Research Institute Netherlands (MARIN) under the MARINET2 project with the same floating substructure, with a focus on better understanding the hydrodynamic loads and reducing uncertainty in the tests by minimizing the system complexity.

The wind turbine was replaced by a stiff tower with resembling inertia properties. The mooring system was simplified by using taut-spring lines with equivalent linear stiffness in surge. This paper reviews the new tests done with the simplified set-up and examines the differences with previous tests done with more complex test set-ups. The main motivation of this work is to study how variations of an experimental set-up can affect the outcome of tests in a wave basin. To start with, the main parameters of the systems (inertia, hydrostatics, and mooring stiffness) for all set-ups are characterized to check how similar they are. Then the level of damping in all systems is compared. Finally, the paper looks at how well the motion responses of this semisubmersible in waves correlate between all these campaigns.
Effects of Wind Farm Down-Regulation in the Offshore Wind Farm Alpha Ventus
Authors: Kretschmer Matthias , Pettas Vasilis , Cheng Po Wen
Published: December 2019

In recent years wind turbine down-regulation has been used or investigated for a variety of applications such as wind farm power optimisation, energy production curtailment and lifetime management. This study presents results from measurement data of tower loads and power obtained from two turbines located in the German offshore wind farm alpha ventus. The free streaming turbine, located closely to a fully equipped meteorological mast, was down-regulated to 50% for a period of 8 months, while the downwind turbine was operating normally. The results are compared to periods where both turbines were operated in normal conditions. Changes in loads and power are analysed according to incoming wind direction and magnitude. Results show a high reduction in the loads of the down regulated turbine, up to a level of 40%. For the turbine in wake the effects in loads are more prominent, showing a maximum reduction of 30%, compared to the effects in power and are seen in a wider sector of about 20° for loads and 10° for power.
Concept Design and Analysis of Wind-Tracing Floating Offshore Wind Turbines
Authors: Li Shuijin , Lamei Azin , Hayatdavoodi Masoud , Wong Carlos
Published: December 2019

Most of the existing floating offshore wind turbines (FOWT), whether in concept or built, host a single turbine. Structures that can host multiple turbines have received attention in recent years, mainly with the aim of reducing the overall cost of energy production and maintenance. A concept challenge of placing multiple wind turbines on a single floating platform is that under variable wind directions, the leading turbines may block the wind against the trailing turbines. In this work, concept design of a wind-tracing floating structure accommodating three wind turbines is presented. The triangular-shapefloating platform is made of pre-stressed concrete, and the turbines are located on the corners. The floating structure uses a single-point mooring system which allows for the entire structure to rotate in response to the change of wind direction. Due to the particular configuration of the floating structure, it is essential to consider the wind, wave and current loads, along with the response of the structure, simultaneously. Response of the FOWT to simultaneous environmental loads from different directions is studied by use of the constant panel approach of the Green function method, subject to constant wind loads on the turbines and linear mooring loads. We also consider the elasticity of the structure by use of finite element analysis, coupled with the hydro- and aero-dynamic loads and responses.
A Low Specific Mass, Free Floating Wind Energy Concept up to 40 MW
Authors: Alexander William
Published: December 2019

Presented here is a low specific mass, free-floating, open ocean, wind energy concept with nominal power capacity to 40 MW, on-board liquid fuels generation, and with operational and survival wave heights to 12 and 40 meters respectively. The estimated specific structural mass of 42 kG/kWp is about 1/3 of the specific mass of much smaller land-based turbines, and less than 6% of the specific structural mass of existing off-shore floating wind turbines. The turbine platform may be operated un-tethered in the open ocean using about 8% of the generated power, on average, for active station keeping. The generated energy may be stored on board via hydrogen electrolysis and liquification for periodic tanker unloading. Reduction of moment loads in the blades and nacelle support structure as well as the unique deep-water foundation result in the low specific mass and high stability.
Structure Design and Assessment of a Floating Foundation for Offshore Wind Turbines
Authors: Ye Qi , Cheng Shanshan , Kim Boksun , Collins Keri , Iglesias Gregorio
Published: December 2019

This paper summarizes the assessment of the structural analysis and design of a floating foundation for offshore floating wind turbine (FWT) based on DNVGL standard and Eurocode in terms of economy and reliability. The wind loads are calculated using empirical equations. The wave loads are obtained and verified using various methods including hand calculation, AQWA and Flow-3D. It is found that the shell thickness could be reduced significantly by introducing the stiffeners (stringer or ring), which can decrease the weight of the hull and lower the cost. While DNVGL and Eurocode yield similar design solutions if using plane shell structures, Eurocode significantly underestimates the buckling resistance of stiffened cylindrical shells.
Damping Identification of the TetraSpar Floater in Two Configurations With Operational Modal Analysis
Authors: Pegalajar-Jurado Antonio , Madsen Freddy J. , Bredmose Henrik
Published: December 2019

Second-order hydrodynamic loads can induce motions at the natural frequencies of a floating wind turbine. These resonant responses are highly dependent on the hydrodynamic damping, which is mostly introduced by viscous effects. Numerically, these viscous effects are often represented by a Morison drag term with relative velocity, which introduces forcing, sea state-dependent linear damping and amplitude-dependent quadratic damping. Recent literature shows that calibration of the Morison drag coefficients to decay tests is not sufficient to achieve an accurate response in the numerical models. In addition, calibration of the drag coefficient alone changes both forcing and damping. Hence, following common practice, additional damping terms are needed, which require calibration against operating conditions. In this study, we apply Operational Modal Analysis (OMA) to wave basin results for the TetraSpar floater of Stiesdal Offshore Technologies. The floater was tested at scale 1:60 with the DTU 10MW reference wind turbine, both in the semi and spar configurations. We identify the linearized damping ratio in surge and pitch for different environmental conditions and investigate its dependency on the sea state and the motion amplitude. Our preliminary results show that the damping of the pitch mode follows increasing trends with significant wave height and motion amplitude, whereas the damping in surge presents a less clear tendency. This is linked to the larger damping level, smaller natural frequency and larger OMA uncertainty for surge. The paper concludes with a discussion of the dependency of OMA estimates on the amount of data and its processing.
Inequivalent Out-Groups in “The Decision III”: The Free Agency of LeBron James and the Power of Sport Rivalry
Authors: Guo Sitong , Billings Andrew C. , Abdallah James C.
Published: December 2019

This study investigated how LeBron James’s free-agency decision in 2018 influences sport fans’ image impressions of him with in-groups (Cleveland Cavaliers) and out-groups (all other NBA teams) compared. In the months preceding James’s free-agency decision, an experimental design was employed to ask self-ascribed fans of LeBron James how they felt about 4 possible free-agency destinations: the Cleveland Cavaliers, the Houston Rockets, the Golden State Warriors, and his eventual selection, the Los Angeles Lakers. A total of 189 U.S. fans of LeBron James were recruited for the study. Results indicate that James’s image became worse (in terms of mean scores) for every out-group condition, while being slightly improved if opting to remain in the in-group; however, images were significantly different from other out-groups in the scenario in which LeBron James opted to join the Golden State Warriors—the Cavaliers most immediate rival at the time.
Allocation of Attention to Visual and Nonvisual Perceptual Channels by Marksmen During Aiming: Skill-Level Differences
Authors: Monfared Shamsi S. , Tenenbaum Gershon , Folstein Jonathan R. , Ericsson K. Anders
Published: December 2019

This study examined attention allocation in 30 marksmen categorized into 3 skill levels ranging from expert to novice. Each shooter performed 336 shooting trials. Half of the trials were performed under an occluded-vision condition and the rest under regular, unoccluded conditions. Immediately after completion of a random subset of shots (96 trials), shooters estimated the actual location of each shot, and on a random subset of trials (48 trials), shooters gave retrospective verbal reports. A mixed 3 × 2 factorial analysis of variance revealed that the expert marksmen performed and estimated their shots more accurately than the intermediate and novice marksmen, the intermediates performed like the experts under the full-vision condition and like novices under the occluded-vision condition, and the experts reported attending more to nonvisual information while they estimated their shots than did the novices. The findings advance our understanding of the mechanisms mediating expertise.
Donkeys face worldwide existential threat
Authors: Lesté-Lasserre Christa
Published: December 2019

Surging demand for hides, used in Chinese medicine, sends populations crashing.
Doubts persist for claimed Alzheimer's drug
Authors: Servick Kelly
Published: December 2019

Once declared a failure, Biogen's antibody drug to be submitted for U.S. approval in 2020.
Depletion of microbiome-derived molecules in the host using
Clostridium
genetics
Authors: Guo Chun-Jun , Allen Breanna M. , Hiam Kamir J. , Dodd Dylan , Van Treuren Will , Higginbottom Steven , Nagashima Kazuki , Fischer Curt R. , Sonnenburg Justin L. , Spitzer Matthew H. , Fischbach Michael A.
Published: December 2019

Clostridial metabolite production

The clostridia are Firmicute bacterial commensals commonly found in the mammalian gut. Clostridia produce a range of metabolites that diffuse into the host's circulation and have been difficult to manipulate genetically, but Guo
et al.
successfully developed a CRISPR-Cas9 deletion system in
Clostridium sporogenes
(see the Perspective by Henke and Clardy). The authors used deletion mutants and mass spectrometry to elucidate clostridial synthesis of several different branched short-chain fatty acids (SCFAs), including isobutyrate, 2-methylbutyrate, and isovalerate. Germ-free mice colonized with mutants incapable of synthesizing SCFAs showed altered immunoglobulin A production. This finding potentially links bacterial SCFA production and host responses to the presence of the clostridia.

Science
, this issue p.
eaav1282
; see also p.
1309
p27 allosterically activates cyclin-dependent kinase 4 and antagonizes palbociclib inhibition
Authors: Guiley Keelan Z. , Stevenson Jack W. , Lou Kevin , Barkovich Krister J. , Kumarasamy Vishnu , Wijeratne Tilini U. , Bunch Katharine L. , Tripathi Sarvind , Knudsen Erik S. , Witkiewicz Agnieszka K. , Shokat Kevan M. , Rubin Seth M.
Published: December 2019

Revised view of anticancer drug mechanism

A crystal structure of the active form of cyclin-dependent kinase 4 (CDK4) provides insight into regulation of the cell cycle and the mechanism of action of a drug used for breast cancer therapy. The protein p27 has been thought to act as a CDK inhibitor. Guiley
et al.
performed a structural analysis of active complexes of CDK4 with cyclin D1 (CycD1) and p27 (see the Perspective by Sherr). The results showed that p27 actually remodels the active site of CDK4 to allow full activation when p27 is phosphorylated on tyrosine (phosp27). Furthermore, they found that the breast cancer drug palbociclib, a CDK4 inhibitor, doesn't actually interact with active phosp27-CDK4-CycD1 trimers. Instead, it appears that the drug, which shows promise in the clinic, binds to inactive CDK4 monomers and prevents interaction with p27.

Science
, this issue p.
eaaw2106
; see also p.
1315
Measuring magnetic field texture in correlated electron systems under extreme conditions
Authors: Yip King Yau , Ho Kin On , Yu King Yiu , Chen Yang , Zhang Wei , Kasahara S. , Mizukami Y. , Shibauchi T. , Matsuda Y. , Goh Swee K. , Yang Sen
Published: December 2019

Diamond-based sensors

Material properties can change dramatically under pressure. Typically, to achieve high-pressure conditions, researchers place their samples in diamond anvil cells (DACs). However, monitoring the properties of the sample inside a DAC is tricky (see the Perspective by Hamlin and Zhou). Hsieh
et al.
, Lesik
et al.
, and Yip
et al.
developed monitoring techniques based on nitrogen-vacancy (NV) centers in diamond. The NV centers can act as sensors because their energy levels and the associated spectra are sensitive to strain and magnetic fields. This enabled optical readout of a spatially resolved signal.

Science
, this issue p.
1349
, p.
1359
, p.
1355
; see also p.
1312
Imaging stress and magnetism at high pressures using a nanoscale quantum sensor
Authors: Hsieh S. , Bhattacharyya P. , Zu C. , Mittiga T. , Smart T. J. , Machado F. , Kobrin B. , Höhn T. O. , Rui N. Z. , Kamrani M. , Chatterjee S. , Choi S. , Zaletel M. , Struzhkin V. V. , Moore J. E. , Levitas V. I. , Jeanloz R. , Yao N. Y.
Published: December 2019

Diamond-based sensors

Material properties can change dramatically under pressure. Typically, to achieve high-pressure conditions, researchers place their samples in diamond anvil cells (DACs). However, monitoring the properties of the sample inside a DAC is tricky (see the Perspective by Hamlin and Zhou). Hsieh
et al.
, Lesik
et al.
, and Yip
et al.
developed monitoring techniques based on nitrogen-vacancy (NV) centers in diamond. The NV centers can act as sensors because their energy levels and the associated spectra are sensitive to strain and magnetic fields. This enabled optical readout of a spatially resolved signal.

Science
, this issue p.
1349
, p.
1359
, p.
1355
; see also p.
1312
Global circulation of Mars’ upper atmosphere
Authors: Benna M. , Bougher S. W. , Lee Y. , Roeten K. J. , Yiğit E. , Mahaffy P. R. , Jakosky B. M.
Published: December 2019

Mapping winds in Mars' upper atmosphere

The atmospheric loss processes that stripped Mars of most of its ancient atmosphere are poorly understood. Benna
et al.
analyzed atmospheric measurements collected by the Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft as it repeatedly dipped into the red planet's upper atmosphere. Combining multiple observing modes allowed the authors to derive wind speeds and map the global circulation of the atmosphere at altitudes of ∼150 kilometers. In some locations, winds followed the slope of the surface topography far below. Such insights into the upper levels of planetary atmospheres are limited, even for Earth.

Science
, this issue p.
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