bluuebunny/crossref_metadata_2025_split huggingface dataset:
Social informal learning and the role of learning climate: Toward a better understanding of the social side of learning among consultants
Authors: Crans Samantha , Bude Veronika , Beausaert Simon , Segers Mien 
Published: March 2021

AbstractThis research examines the social side of learning among professionals in the fast evolving and knowledge intense field of consultancy. Its first aim is to unravel social informal learning by proposing a new, integrated framework of workplace learning. Its second aim is to explore the role of learning climate for social informal learning behavior among consultants. Our qualitative inquiry using interviews based on the critical incident technique illustrates that consultants engaged in deliberative and reactive learning, thereby indicating a clear intention to learn. The source of learning was often the direct colleagues and direct supervisor, which highlights the relevance of close proximity of other individuals. The consultants mainly learned from others in a passive manner, followed by proactive and collaborative learning. Finally, this study shows that granting professionals responsibility and autonomy in their learning process as well as having a leader who facilitates learning are important elements of a learning climate that enhances social informal learning. We conclude with recommendations for organizations and directions for future research.
Peristaltic motion with heat and mass transfer of nano‐Williamson fluids in two layers
Authors: Shawky Hameda M. , Eldabe Nabil T. 
Published: March 2021

AbstractIn this paper, we have investigated the peristaltic motion with heat and mass transfer through a vertical channel divided into two equal regions, the right region filled with a clear non‐Newtonian fluid obeying the Williamson model and the left region with a nano‐Williamson fluid. The system is stressed by a gravity force with a uniform external magnetic field. The problem is modulated mathematically with a system of coupled nonlinear partial differential equations that describe the velocities, temperatures, and concentration of the fluids. The system of nondimensional, nonlinear, and partial differential equations is solved analytically with the homotopy perturbation method after using the approximations of low Reynolds number and long wavelength. The obtained solutions are functions of the physical parameters of the problem. Then, the effects of these parameters on velocities, temperatures, and concentration are discussed numerically and illustrated graphically through a set of figures. It is found that the parameters play an important role in controlling the solutions. It is shown that the stream function decreases on the left side and increases on the right side with an increase in the Wissenberger parameter and thermal conductivity ratio. Also, the temperature in the two regions increases with an increase in the thermophoretic parameter, whereas it decreases with an increase in the Brownian motion parameter. Furthermore, the concentration increases with an increase in the Brownian motion parameter and decreases with an increase in the thermophoretic parameter.
Characterization of subsurface fluxes at the plot scale during flash floods in the Valescure catchment, France
Authors: Bouvier Christophe , Adamovic Marko , Ayral Pierre‐Alain , Brunet Pascal , Didon‐Lescot Jean‐François , Domergue Jean‐Marc , Spinelli Rosario 
Published: March 2021

AbstractThis study focuses on a 10‐m2 plot within a granitic hillslope in Cevennes mountainous area in France, in order to study infiltration and subsurface hydrological processes during heavy rainfalls and flash floods. The monitoring device included water content at several depths (0–70 cm for the shallow soil water; 0–10 m for the deep water) during both intense artificial and natural rainfall events, chemical and physical tracers, time‐lapse electrical resistivity tomography. During the most intense events, the infiltrated water was estimated to be some hundreds of millimetres, which largely exceeds the topsoil capacity (≤40 cm deep in most of the cases). The weathered/fractured rock area below the soil clearly has an active role in the water storage and sub‐surface flow dynamics. Vertical flow was dominant in the first 0–10 m, and lateral flow was effective at 8–10 m depth, at the top of the saturated area. The speed of the vertical flow was estimated between 1 and 10 m/hr, whereas it was estimated between 0.1 and 1 m/hr for the lateral flow. The interpretation of the experiments might lead to a local pattern of the 2D‐hydrological processes and profile properties, which could be generic for most of the mountainous catchments under Mediterranean climate. It suggests that fast triggering of floods at the catchment scale cannot be explained by a mass transfer within the hillslope, but should be due to a pressure wave propagation through the bedrock fractures, which allows exfiltration of the water downstream the hillslope.
Quantifying ice storage in upper Indus river basin using ground‐penetrating radar measurements and glacier bed topography model version 2
Authors: Zou Xiaojuan , Gao Haifeng , Zhang Yinsheng , Ma Ning , Wu Jianfeng , Farhan Suhaib Bin 
Published: March 2021

AbstractIce reserve estimates is a fundamental prerequisite for water resources management. We selected the UIB (upper Indus river basin) as study area because it contains the most abundant mid‐latitude glaciers outside the polar region, however, the ice reserve estimates remain unclear due to the harsh topography. In this study, we validated the parameters of the GlabTop2 model (Glacier Bed Topography version 2) using the ice thickness measured by GPR (ground‐penetrating radar) and compared the “GPR‐measured ice thickness and ice bed elevation” versus “the estimated results obtained from GlabTop2.” Integrated with IDW (inverse distance weighted) interpolated results of glaciers of various sizes, a reasonable parametric scheme (τ = 120 kPa and f = 0.8) of GlabTop2 was applied on vast amounts of glaciers in the UIB region. The GlabTop2 estimates indicated that the ice thickness of the UIB varied from 0 to 736.0 ± 110.0 m, with an average value of 74.5 ± 11.2 m. A significant spatial heterogeneity exists in the sub‐basins. The Shyok, Shigar and Hunza that contain the most abundant ice reserve. Lesser quantities are stored in the Western Himalaya and Hindu Kush ranges, which account for 11.3 % and 6.7 % of the total ice reserve in the UIB, respectively. A total volume of 1162.4 ± 175.1 km3 of glacier can be converted to 1046.2 ± 157.6 Gt ice reserve; this is 13.6 times the annual average discharge obtained from the outlet of the Besham hydrological station. We aim to present estimates that can provide the baseline information for glaciology study of the Indus river.
The Bear Brook Watershed in Maine: Multi‐decadal whole‐watershed experimental acidification
Authors: Patel Kaizad F. , Fernandez Ivan J. , Nelson Sarah J. , Norton Stephen A. , Spencer Cheryl J. 
Published: March 2021

AbstractThe Bear Brook Watershed in Maine (BBWM) is a long‐term research site established to study the response of forest ecosystem function to environmental disturbances of chronic acidic deposition and ecosystem nitrogen enrichment. Starting in 1989, the West Bear (treated) watershed received bimonthly applications of ammonium sulfate [(NH4)2SO4] fertilizer from above the canopy, whereas East Bear (reference) received ambient deposition. The treatments were stopped in 2016, marking the beginning of the recovery phase. Research at the site has focused on soils, streams, and vegetation. Here, we describe data collected over three decades at the BBWM—input and stream output nutrient fluxes, quantitative soil pits and soil chemistry, and soil temperature and moisture.
Pyricularia oryzae incites gray leaf spot disease on hard fescue (Festuca brevipila)
Authors: Vines P. L. , Daddio R. M. , Luo J. , Wang R. , Murphy J. A. , Zhang N. , Clarke B. B. , Meyer W. A. , Bonos S. A. 
Published: March 2021

AbstractGray leaf spot, caused by the fungal pathogen Pyricularia oryzae, is a widespread and destructive foliar disease of turfgrasses in the United States. Characteristic gray leaf spot disease symptoms were observed on hard fescue (Festuca brevipila Tracey) turf in New Jersey during October 2018. Prior to this observation, P. oryzae had not been documented as a pathogen of F. brevipila. Therefore, this study was conducted to determine if P. oryzae was the cause of the observed gray leaf spot disease symptoms. Morphological assessments and molecular analyses identified fungal isolates as the potential incitant from symptomatic F. brevipila turf as P. oryzae. Two isolates of P. oryzae (D300452 and 181001P12) and two F. brevipila cultivars (‘Beacon’ and ‘Reliant IV’) were used in growth chamber studies to fulfill Koch's postulates for pathogenicity. Inoculations were carried out using conidial suspensions at 4 × 104 conidia ml−1 concentration. Disease symptoms were observed 7 d post‐inoculation for both isolates on both cultivars. Koch's postulates were fulfilled by morphological evaluations and DNA sequencing of the reisolated fungi. This study confirms that P. oryzae is the causal agent of gray leaf spot disease on F. brevipila. Given the historical significance of gray leaf spot disease in other turf species, this study suggests that gray leaf spot could be a major concern for managing F. brevipila turf in the future.
Evaluation and genetic analysis of red thread (Laetisaria fuciformis) disease prevalence in tall fescue (Festuca arundinacea)
Authors: Qu Yuanshuo , Green Edwin J. , Vines Phillip L. , Wu Shidi , Clarke Bruce B. , Bonos Stacy A. , Meyer William A. 
Published: March 2021

AbstractRed thread, caused by [Laetisaria fuciformis (Berk.) Burds.], is a common disease on many cool‐season and some warm‐season grasses throughout the world. Low reproducibility of experiments under both natural and artificial infection and inadequate understanding of the underlying genetics have limited the selection of turfgrass for resistance to red thread. This study investigated red thread prevalence of tall fescue (Festuca arundinacea Schreb.) populations in two locations over multiple years, estimated disease prevalence in a broad collection of tall fescue populations, and calculated heritability of disease prevalence with two different experimental designs. Collections from Albania and Romania, as well as those that were recently backcrossed to adapted germplasm, were more susceptible to red thread compared with the rest of the populations, highlighting the importance of selection efforts against red thread disease in tall fescue. Narrow‐sense heritability (0.52, 0.74, and 0.48) estimated from different experimental designs were all in the range of moderate to high, indicating a large proportion of additive genetic variance in red thread prevalence among tall fescue populations. Hence, prevalence of red thread in tall fescue can be effectively reduced through selection and breeding. This is also the first report documenting the efficacy of family selection in reducing red thread prevalence in tall fescue.
Etiology and management of Pythium root rot in golf course putting greens
Authors: Hampy Halle D. , Van Ryzin Benjamin J. , Butler E. Lee , Kerns James P. 
Published: March 2021

AbstractPythium root rot (PRR), caused by various Pythium species, is a major disease of creeping bentgrass in the transition zone of the United States. Characterization of various Pythium species associated with PRR was determined by identifying 106 Pythium isolates from samples of symptomatic turfgrass cores. Pathogenicity assays were conducted on post‐emergent (7‐day old) seedlings and mature (5‐week old) creeping bentgrass plants that were inoculated with four different Pythium spp. and incubated at 34 ℃/28 ℃ for 1 to 5 weeks. The results demonstrated that pathogenicity on post‐emergent seedlings may not correlate with pathogenicity on mature plants. The sensitivity of various Pythium spp. to ten commercially available fungicides was determined through in vitro mycelial growth assays. Isolates (n = 20) varied in sensitivity to fungicides across and within species of Pythium. Management of PRR was determined through field experiments, revealing that cyazofamid‐based treatments were most effective when applied preventatively in the early summer, and were able to reduce disease severity when applied curatively.
Effects of nitrogen, phosphorus and potassium rates on Microdochium patch
Authors: McDonald Brian , Kowalewski Alec , Mattox Clint , Braithwaite Emily , Schmid Charles 
Published: March 2021

AbstractResearch on nitrogen (N), phosphorus (P) and potassium (K) ratios have suggested that maintaining the proper balance of those nutrients is critical to disease mitigation. However, research on N, P, and K ratios relevant to annual bluegrass (Poa annua L.) and Microdochium patch (Microdochium nivale) is not available. The objective of this research was to evaluate the effects of winter‐applied N, P, and K rates in combination with sulfur and phosphorous acid on Microdochium patch development within an annual bluegrass putting green in the absence of traditional fungicides. Field research was conducted from October 2018 to April 2019 on a mature sand‐based annual bluegrass putting green. Factors included monthly applications of urea nitrogen (46–0–0) rate (4.9 kg N ha–1 and 9.8 kg N ha–1), phosphorus rate (0.0 kg P ha–1 and 1.22 kg P ha–1), and potassium rate (0.0 kg K ha–1 and 4.9 kg N ha–1). To avoid extreme disease levels, all of these treatments received monthly applications of phosphorous acid. When comparing nitrogen treatments across both rates vs. nitrogen combined with P, K or both, disease levels decreased from 9.9 percent (urea only) to 5.5 percent (urea with P, K, or both). Additionally, when nitrogen rates increased from 4.9 kg N ha–1 to 9.8 kg N ha–1, the percent disease decreased from 8.4 to 4.8 percent. Findings from this project suggest that applying nitrogen only as urea will lead to more Microdochium patch vs. applying urea with P, K, or both, and nitrogen applied at the higher rate will decrease Microdochium patch incidence.
Genetic identity and diversity among experimental selections and cultivars of vegetatively propagated turf bermudagrass as assessed with SSR markers
Authors: Godwin Carly , Fang Tilin , Wu Yanqi 
Published: March 2021

AbstractTurf bermudagrass (Cynodon spp.) is the most common, warm‐season, sod‐forming perennial grass for residential lawns, sports fields, golf courses, and public landscapes in warm climates across the world. Genetic diversity and identity information are important for breeding new cultivars and production certification. Accordingly, this experiment was designed to genotype experimental selections along with commercial cultivars to analyze their genetic diversity. Nineteen advanced selections from the Oklahoma State University (OSU) turfgrass breeding program and 13 cultivars were used in the genetic analysis. Fifty‐four simple sequence repeat (SSR) primer pairs (PPs) selected across the bermudagrass genome produced 618 polymorphic PCR fragments, of which 120 fragments amplified by using 48 SSRs were unique to the 19 experimental selections. Genetic similarity coefficients varied from 0.69 to 1.00. The AMOVA results indicated 94% of the variation resided within the selections or cultivars. The UPGMA analysis showed that groupings were associated with origins of their parental germplasm. The seventeen distinct experimental selections identified were genetically different from all commercial cultivars tested, demonstrating the potential of adding genetic diversity to the existing cultivar pool if one or more of the experimental genotypes are released for commercial production.
SCANTURF ‐ Evaluation of turfgrass varieties for lawns and sports grounds in Scandinavia
Authors: Havstad Lars T. , Niskanen Markku , Larsen Anders S. , Aamlid Trygve S. 
Published: March 2021

AbstractSCANTURF is a joint Nordic programme for turfgrass variety testing, set up in 2005 and funded by variety entrance fees only. It replaced and simplified the former government‐funded national evaluation programmes in Finland, Sweden, Denmark and Norway. The programme includes testing of all cool‐season grasses on lawn/fairways at 15–20 mm mowing height (“lawn trials”) and optional testing of Poa pratensis L. and Lolium perenne L. on simulated football pitches with wear, mowed at 30 mm (“wear trials”). Since 2013, the program has regarded the Nordic countries as one trial zone with three test sites: Tystofte Denmark (55°15′ N, 11°20′ E), Landvik, Norway (58°21’ N, 8°32’ E) and Ylistaro, Finland (62°57′ N, 22°31’ E). Wear trials are carried out at the intermediate location Landvik only. Candidate varieties are tested against two reference varieties of the same species or subspecies. In the lawn trials, candidate varieties are evaluated for visual merit (overall turfgrass quality), winter damage, winter color, diseases and daily height growth at all three locations and for tiller density, fineness of leaves, in‐season (genetic) color, at Landvik only. Based on the results from the SCANTURF trials in 2014–2016 and 2016–2018, the candidate varieties Fabian, Tetrastar, Annecy, and Monroe (Lolium perenne), Becca, Harmonie, Traction, and Markus (Poa pratensis) and Lystig, Greenmile, and Humboldt (Festuca rubra ssp. commutata) were recommended for lawns in the Nordic countries, while Eurocordus, Columbine, Monroe, and Annecy (Lolium perenne) and Harmonie (Poa pratensis) were recommended for sports grounds. More use of the recommended varieties will have a positive effect on quality of lawns and sport grounds in the Nordic countries. Less winter injury and increasing relative performance with increasing latitude of the tetraploid perennial ryegrass variety Fabian in the lawn trials may possibly lead to more use of perennial ryegrass in the northern and more continental parts of the region.
Evaluating biological thatch control in turfgrass
Authors: Weaver Josh R. , McCarty Lambert B. , Quisenberry Virgil L. , Hubbard L. Ray , Bridges William G. , Brown Philip J. 
Published: March 2021

AbstractThatch is a layer of living and dead plant material between turfgrass leaf tissue and soil surface; it can decrease playability, increase scalping and disease pressure, reduce pesticide efficacy and water infiltration, plus harbor insects. In golf putting greens, disruptive mechanical practices such as vertical mowing, core cultivation, grooming, and topdressing are traditionally used for managing thatch; however, several biological products have been marketed as non‐disruptive thatch reducers. Greenhouse experiments were conducted to evaluate thatch reduction and rooting depth of two commercial humic acid based biostimulant products, Worm Power (WP) and EarthMAX (EM). Products were applied at labelled rates and timings. EM was applied at two rates, indicated as EM (1) and EM (2). Two industry standards were also included: blackstrap molasses and sand topdressing. For both years, blackstrap molasses, EM (1), and EM (2) reduced thatch thickness compared to untreated by 30, 24, and 18% respectively. However, no decrease in thatch weight by treatment was observed. In Year 1, EM (1), and sand topdressing provided an average of 16% greater root length than untreated. However, in Year 2, WP provided 16% greater root length than untreated. EM (1) provided 117% greater root mass than untreated control in Year 2. No treatment provided greater root mass in Year 1. Thatch depth reduction indicate these products may be beneficial, but, inconsistent results mean further research is required.
Aboveground and belowground traits of turf‐type bahiagrass (Paspalum notatum Flügge) genotypes under simulated drought
Authors: Boeri P. Agustin , Unruh J. Bryan , Kenworthy Kevin E. , Trenholm Laurie E. , Rios Esteban F. 
Published: March 2021

AbstractAs awareness of environmental impacts of anthropogenic ecosystems increases, low input turfgrass species like bahiagrass (Paspalum notatum Flügge) may become more prominent in urban landscapes and on golf courses. A study was conducted at the West Florida Research and Education Center, Jay, FL, USA, to evaluate the performance of novel turf‐type bahiagrass genotypes under drought conditions. The experiment was arranged as a completely randomized block design. Three Wilmington‐mutants, three Argentine‐mutants, two experimental lines, and two industry standards [‘Argentine’ and ‘Empire’ zoysiagrass (Zoysia japonica Steud.)] were selected for this trial. Aboveground and belowground characteristics were evaluated by growing the grasses in clear acrylic tubes under greenhouse conditions. A progressive dry‐down and well‐watered control comprised the treatments. The tubes were weighed daily to determine their transpiration break and midpoints. The rate of root depth development (RRDD) was recorded by measuring the single visible deepest root. At the end of the dry down, plant roots were harvested and analyzed using WinRhizo. Although total root growth was reduced under drought conditions, plants tended to have faster vertical root growth and prioritized root development in the lower soil depths. Root length density (RLD) and the distribution of RLD in the lower soil depths, fast RRDD, and high transpiration midpoints were the most important drought responsive traits. These attributes were consistently observed on genotypes WilM10 and ArgM27.
Sod production characteristics: How strong is your bermudagrass?
Authors: Segars Chrissie A. , Moss Justin Quetone , Martin Dennis L. , Wu Yanqi 
Published: March 2021

AbstractFor new, vegetatively propagated turfgrass cultivars to be successful in the marketplace, they must not only possess characteristics desired by the end user, but also have those preferred by the sod producer. The objectives of this study were (1) to investigate different sod production characteristics of advanced clonal bermudagrass [C. dactylon (L.) Pers. × C. transvaalensis Burtt‐Davy] lines that show improved characteristics and (2) to examine the relationship between those production characteristics. Production characteristics measured include: sod handling quality (SHQ), sod tensile strength (STS), vertical growth (VG), and underground growth characteristics. Results showed a positive correlation (r2 = 0.65) between SHQ and STS. Other production characteristics moderately correlated or did not correlate at all. Knowledge of growth characteristics can aid breeders in choosing breeding lines that will add value to the sod industry.