Journal articles on the topic 'SMALL-MID-LEVEL INFLUENCER'

To see the other types of publications on this topic, follow the link: SMALL-MID-LEVEL INFLUENCER.

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the top 50 journal articles for your research on the topic 'SMALL-MID-LEVEL INFLUENCER.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.

1

Tadjoeddin, Mohammad Zulfan, Ilmiawan Auwalin, and Anis Chowdhury. "Revitalising Indonesia’s Manufacturing." European Journal of East Asian Studies 16, no. 1 (2017): 124–53. http://dx.doi.org/10.1163/15700615-01601003.

Full text
Abstract:
In light of the continuing importance, but declining dynamism, of the manufacturing sector, this paper investigates trends in productivity at firm levels. It finds that labour productivity has been either stagnant or falling in labour-intensive manufacturing. The paper uses firm level cross-sectional and time series data and employs GMM techniques to estimate determinants of productivity. It finds that real wage is the most important variable that influences firm level productivity, followed by capital intensity. Contrary to the common perception, foreign ownership and export orientation are not found to have statistically significant influence on firm level productivity. This finding is consistent for firms of all sizes—large, medium, small and micro. This implies that Indonesia can use wages policy, as Singapore did during the late 1970s to mid-1980s, to upgrade its manufacturing to higher value-added activities.
APA, Harvard, Vancouver, ISO, and other styles
2

Noe, Gregory B., Norman A. Bourg, Ken W. Krauss, Jamie A. Duberstein, and Cliff R. Hupp. "Watershed and Estuarine Controls Both Influence Plant Community and Tree Growth Changes in Tidal Freshwater Forested Wetlands along Two U.S. Mid-Atlantic Rivers." Forests 12, no. 9 (August 31, 2021): 1182. http://dx.doi.org/10.3390/f12091182.

Full text
Abstract:
The tidal freshwater zone near the estuarine head-of-tide is potentially sensitive to both sea-level rise and associated salinity increases as well as changing watershed inputs of freshwater and nutrients. We evaluated the vegetation response of tidal freshwater forested wetlands (TFFW) to changes in nontidal river versus estuarine controls along the longitudinal gradient of the Mattaponi and Pamunkey rivers in the Mid-Atlantic USA. The gradient included nontidal freshwater floodplain (NT) and upper tidal (UT), lower tidal (LT), and stressed tidal forest transitioning to marsh (ST) TFFW habitats on both rivers. Plot-based vegetation sampling and dendrochronology were employed to examine: (1) downriver shifts in plant community composition and the structure of canopy trees, understory trees/saplings/shrubs and herbs, tree basal-area increment (BAI) and (2) interannual variability in BAI from 2015 dating back as far as 1969 in relation to long-term river and estuary monitoring data. With greater tidal influence downstream, tree species dominance shifted, live basal area generally decreased, long-term mean BAI of individual trees decreased, woody stem mortality increased, and live herbaceous vegetative cover and richness increased. Acer rubrum, Fagus grandifolia, Ilex opaca, and Fraxinus pennsylvanica dominated NT and UT sites, with F. pennsylvanica and Nyssa sylvatica increasingly dominating at more downstream tidal sites. Annual tree BAI growth was positively affected by nontidal river flow at NT and UT sites which were closer to the head-of-tide, positively influenced by small salinity increases at LT and ST sites further downstream, and positively influenced by estuarine water level throughout the gradient; nutrient influence was site specific with both positive and negative influences. The counterintuitive finding of salinity increasing tree growth at sites with low BAI is likely due to either competitive growth release from neighboring tree death or enhanced soil nutrient availability that may temporarily mitigate the negative effects of low-level salinization and sea-level increases on living TFFW canopy trees, even as overall plant community conversion to tidal marsh progresses.
APA, Harvard, Vancouver, ISO, and other styles
3

Kreye, Jesse K., J. Kevin Hiers, J. Morgan Varner, Ben Hornsby, Saunders Drukker, and Joseph J. O’Brien. "Effects of solar heating on the moisture dynamics of forest floor litter in humid environments: composition, structure, and position matter." Canadian Journal of Forest Research 48, no. 11 (November 2018): 1331–42. http://dx.doi.org/10.1139/cjfr-2018-0147.

Full text
Abstract:
Much of fire behavior is driven by fine-scale patterns of fuel moisture; however, moisture predictions typically occur over large scales. The source of fine-scale variation in moisture results from a combination of fuelbed properties and overstory forest structure that influences water movement and distribution of solar radiation. Fine-scale moisture variation is of particular relevance in humid forests managed with frequent prescribed fire where fire behavior variation is tightly linked to differential fire effects. Results of a three-tiered experiment combining laboratory and field methods demonstrated that solar radiation exerted a strong influence on fuel moisture patterns in a temperate humid pine forest. Infrared radiation more rapidly dried Quercus and Pinus litter in laboratory experiments compared with controls. Litter exposed to sunlight during small-scale outdoor experiments was significantly drier than shaded litter. Quercus litter was wetter than Pinus on mornings, but dried more rapidly, becoming drier than Pinus litter by mid-day when exposed to sunlight. Field observations validated small-scale outdoor and laboratory results but also revealed the influence of fuel position: elevated litter was wetter than ground-level litter at peak burning time. Results provide insight into how overstory structure and composition may influence fine-scale heterogeneity of surface moisture dynamics and fire behavior.
APA, Harvard, Vancouver, ISO, and other styles
4

Newcomb, Patricia, Andrew Hunt, Pamela Rast, Denise Cauble, Nancy Rowe, and Jianling Li. "Acute Effects of Walking Environment and GSTM1 Variants in Children With Asthma." Biological Research For Nursing 14, no. 1 (December 30, 2010): 55–64. http://dx.doi.org/10.1177/1099800410389167.

Full text
Abstract:
Background:Exercise in air polluted by traffic emissions may aggravate airway inflammation in children with asthma, particularly those who produce decreased glutathione-S transferase (GST) as a result of GSTM1 gene deletion. Objectives: This pilot crossover study investigated whether children with asthma experience more airway changes when exercising outdoors near roadways than when exercising indoors. It also examined differences in risk between children with and without GSTM1 deletion. Method: Children between the ages of 5 and 12 years were assigned to groups and walked daily for 1 week in each exercise condition. Airway inflammation indicated by exhaled nitric oxide (eNO) and pulmonary functions measured as forced expiratory volume in 1 s (FEV1) and mid-expiratory flow rate were measured at baseline and at three intervals during the walking program. Independent variables of interest included walking condition (place), time of walking, genotype, and particulate matter (PM) exposure. Results: A linear mixed models approach was used to investigate the contributions of targeted variables to respiratory outcomes. Results indicated that walking location and ambient level of ultrafine particulates during walking influenced function of small airways. Absence of one or both alleles for the GSTM1 gene did not influence airway function acutely. Discussion: Mid-expiratory flow (FEF25-75) may be more informative than FEV1 in studies of acute lung function changes in children with asthma. Further study of the effects of varied environmental conditions on lower airway function of children is needed to optimize exercise experiences for urban children with asthma.
APA, Harvard, Vancouver, ISO, and other styles
5

Lee, Jaeseok, and Jongmin Yu. "Heterogenous Energy Consumption Behavior by Firm Size: Evidence from Korean Environmental Regulations." Sustainability 11, no. 11 (June 11, 2019): 3226. http://dx.doi.org/10.3390/su11113226.

Full text
Abstract:
We analyze the interdependencies between energy usage, energy costs, renewable energy shares, economic growth, and greenhouse gas (GHG) emissions in the Korean industrial sector by employing a time-series panel vector model. Although the topic itself about has been classic one, our research to investigate diverse dynamics between large and small-mid size businesses using micro-firm level data is the first study in literature. Since firms with different sizes are put in different policy circumstances, the aggregate-level data analysis could possibly disregard the effectiveness of environmental & renewable policies and underestimate the policy sensitivity of firms. Our findings demonstrate that the increase in energy consumption in larger firms has a greater impact on their energy costs and GHG emissions than for small and medium-sized enterprises (SMEs). Moreover, it has a significant effect on GDP. Also, the increase in renewable energy shares only has a significant influence on the energy consumption and GHG emission levels of large firms.
APA, Harvard, Vancouver, ISO, and other styles
6

Evtushevsky, Oleksandr, Andrew R. Klekociuk, Volodymyr Kravchenko, Gennadi Milinevsky, and Asen Grytsai. "The influence of large amplitude planetary waves on the Antarctic ozone hole of austral spring 2017." Journal of Southern Hemisphere Earth Systems Science 69, no. 1 (2019): 57. http://dx.doi.org/10.1071/es19022.

Full text
Abstract:
Quasi-stationary planetary wave activity in the lower Antarctic stratosphere in the late austral winter was an important contributor to the preconditioning of the ozone hole in spring 2017. Observations show that the ozone hole area (OHA) in spring 2017 was at the level of 1980s, that is, almost half the maximum size in 2000s. The observed OHA was close to that forecasted based on a least-squares linear regression between wave amplitude in August and OHA in September–November. We show that the key factor which contributed to the preconditioning of the Antarctic stratosphere for a relatively small ozone hole in the spring of 2017 was the development of large-amplitude stratospheric planetary waves of zonal wave numbers 1 and 2 in late winter. The waves likely originated from tropospheric wave trains and promoted the development of strong mid-latitude anticyclones in the lower stratosphere which interacted with the stratospheric polar vortex and strongly eroded the vortex in August and September, mitigating the overall level of ozone loss.
APA, Harvard, Vancouver, ISO, and other styles
7

Wang, Qiang, Qi Shu, Sergey Danilov, and Dmitry Sidorenko. "An extreme event of enhanced Arctic Ocean export west of Greenland caused by the pronounced dynamic sea level drop in the North Atlantic subpolar gyre in the mid-to-late 2010s." Environmental Research Letters 17, no. 4 (March 25, 2022): 044046. http://dx.doi.org/10.1088/1748-9326/ac5562.

Full text
Abstract:
Abstract The North Atlantic subpolar gyre influences the climate in many different ways. Here, we identified that it is also responsible for a recent extreme event of Arctic Ocean freshwater export west of Greenland. A shift in climate regimes occurred in the mid-2000s, with a significant negative trend in the dynamic sea level in the subpolar gyre since then. We found that the dynamic sea level drop induced a strong increase in freshwater export west of Greenland, in particular from 2015 to 2017, when the sea level was close to the minimum. Sea ice melting and atmospheric variability in the Arctic had only a small contribution to this event. As the exported water from the Arctic Ocean has low salinity and constituents of chemical tracers very different from those in the North Atlantic, such events might have impacts on the North Atlantic ecosystem and the climate as well. Our study suggests that such events might be predictable if the subpolar gyre sea level has certain predictability.
APA, Harvard, Vancouver, ISO, and other styles
8

Zhao, Dandan, and Hong Zhou. "Livelihoods, Technological Constraints, and Low-Carbon Agricultural Technology Preferences of Farmers: Analytical Frameworks of Technology Adoption and Farmer Livelihoods." International Journal of Environmental Research and Public Health 18, no. 24 (December 18, 2021): 13364. http://dx.doi.org/10.3390/ijerph182413364.

Full text
Abstract:
In the context of achieving carbon neutrality, it is scientifically important to quantitatively explore the relationships among livelihoods, technological property constraints, and the selection of low-carbon technologies by farmers to promote agricultural modernization and carbon neutrality in the agricultural sector of China. Based on the scientific classifications of farmer capital and low-carbon agricultural technologies, a farmer technology selection theory model considering capital constraints was developed in this study. Microcosmic survey data were collected from farmers in the Jiangsu province for empirical testing and analyses. A total of four low-carbon technologies related to fertilizer usage and three types of farmers’ livelihoods and their relationships were examined by using a logistic model. The results showed the existence of a significant coupling relationship between the intrinsic decision mechanism involved in selecting low-carbon agricultural technology and the properties of low-carbon agricultural technology for different types of farmers. Significant differences exist in the selection of different low-carbon technologies among large-scale farmers, mid-level part-time farmers, and low-level (generally small) part-time farmers. (1) When selecting technology, large-scale farmers are more inclined to accept capital-intensive, low-carbon technologies, such as new varieties, straw recycling, soil testing, and formulated fertilization. Mid-level part-time farmers are more inclined to accept capital intensive, labor saving, or low risk low-carbon agricultural technologies. In contrast, low-level part-time farmers are inclined to accept labor intensive technologies to reduce capital constraints and agricultural risks. (2) Large-scale farmers and low-level part-time farmers are influenced by household and plot characteristics, while mid-level part-time farmers are more influenced by plot characteristics. (3) Households with capital constraints created by differentiated livelihoods face challenges adopting capital-intensive low-carbon agricultural technologies, such as straw recycling, new varieties, soil testing, and formulated fertilization. However, farmers with stronger constraints in the areas of land and labor are more inclined to accept labor-saving technologies, such as soil testing and formulated fertilization technology. Moreover, farmers with stronger risk preferences tend to accept high-risk technologies, such as new technologies like straw recycling. The results of this study can provide a scientific basis for formulating carbon emission reduction policies and low-carbon technology policies for the agricultural sector.
APA, Harvard, Vancouver, ISO, and other styles
9

Leighton, Lindsey R., and Chris L. Schneider. "Taxon characteristics that promote survivorship through the Permian–Triassic interval: transition from the Paleozoic to the Mesozoic brachiopod fauna." Paleobiology 34, no. 1 (2008): 65–79. http://dx.doi.org/10.1666/06082.1.

Full text
Abstract:
Examination of organismal characteristics which promote survivorship through both background and mass extinctions may reveal general ecological principles potentially critical to modern conservation efforts. This study explores survivorship of brachiopods, a highly diverse and abundant Paleozoic clade, through the mid-Permian to mid-Triassic interval, which includes the greatest mass extinction in the history of metazoan life. This interval of time separates two of the major Phanerozoic evolutionary faunas. In this regard, survivorship across any one extinction during the interval would not have been relevant if the survivor went extinct shortly after the extinction event; surviving background extinction is as important as surviving a mass extinction. Similarly, taxa that survived but failed to rediversify also were not major elements of the Mesozoic evolutionary fauna. Thus, the analysis aims to analyze survivorship not just across a single extinction but across the entire mid-Permian to mid-Triassic; only survivors through the entire interval can be the ancestors of the Mesozoic clades.Fewer brachiopod genera survived the interval than did brachiopod clades, suggesting that pseudoextinction or insufficient sampling could be a problem in analyzing these extinctions; thus, survivorship analysis should be conducted at the clade level. Nine characteristics were examined for generic representatives of 20 North American brachiopod clades, five of which survived both Permian extinctions and the subsequent earliest Triassic transitional interval. Characteristics include both those that operate on global scales and those that operate on the higher-resolution scales of individuals and populations.Survivors were significantly smaller and occurred less frequently than victims. Mean diversity of communities in which survivors were present was significantly greater. The finding that rare taxa belonging to high-diversity communities were more likely to survive runs counter to traditional predictions. However, these results are consistent with recent studies suggesting that higher diversity within a trophic level may create a buffer, as surviving taxa quickly occupy the vacant niche space of the victims. As size, abundance, and community diversity are all statistically related, the small size of survivors may be an artifact of reduced biovolume per taxon in a diverse community.No significant relationship exists between global-scale processes and survivorship of brachiopods through the mid-Permian to mid-Triassic. The results suggest that ecological processes can strongly influence global extinction patterns.
APA, Harvard, Vancouver, ISO, and other styles
10

Koh, Stephen C. L., R. N. V. Prasad, and Y. F. Fong. "Hemostatic Status and Fibrinolytic Response Potential at Different Phases of the Menstrual Cycle." Clinical and Applied Thrombosis/Hemostasis 11, no. 3 (July 2005): 295–301. http://dx.doi.org/10.1177/107602960501100308.

Full text
Abstract:
Coagulation and fibrinolytic variables including platelet function and endogenous fibrinolytic response were determined in 30 normal healthy women volunteers not on any known medication during the period of study. They were between 18 years and 38 years old and had normal menstrual cycles of between 28 days and 30 days. Blood samples were obtained within one menstrual cycle and after having fasted overnight within days 1 to 3 (menstruation), 5 to 9 (follicular), 10 to 14 (mid-cycle), and 21 to 26 (luteal) of the menstrual cycle. Analysis of variance (ANOVA) showed no significant differences in the hemostatic parameters studied between the phases of the menstrual cycle except for a reduced D-dimer level at mid-cycle. Significant fibrinolytic response was seen after venous occlusion but they were not significantly different between the phases of the menstrual cycle. The women were then divided into either normal weight (n=22) or overweight (n=8) according to World Health Organization (WHO) classification and the data reanalyzed. Elevated tissue plasminogen activator antigen and plasminogen activator inhibitor-1 levels except at menstruation and total protein S except at follicular phase were observed in overweight women together with increased plasminogen level only at luteal phase. Significant endogenous fibrinolytic response seen during the menstrual cycle was not different between normal and overweight women. The study demonstrated that systemic coagulation, fibrinolysis, and platelet function were probably not influenced by natural hormonal changes occurring during the menstrual cycle except for an associated reduced fibrinolytic state at mid-cycle. The hemostatic system in this small group of healthy overweight women studied appeared to be physiologically compromised.
APA, Harvard, Vancouver, ISO, and other styles
11

Candela, Vincenzo, Umile Giuseppe Longo, Mauro Ciuffreda, Giuseppe Salvatore, Alessandra Berton, Matteo Cimmino, and Vincenzo Denaro. "Talar osteochondral size influences outcome after bone marrow stimulation: a systematic review." Journal of ISAKOS: Joint Disorders & Orthopaedic Sports Medicine 2, no. 6 (October 27, 2017): 318–24. http://dx.doi.org/10.1136/jisakos-2016-000092.

Full text
Abstract:
ImportanceNo accepted definition of lesion size exists to treat osteochondral defects (OCD) of talus with bone marrow stimulation.ObjectiveThe aim of this study is to establish a relationship between the clinical outcomes and size of OCD lesion to identify the area or diameter best suited to be treated with arthroscopic bone marrow stimulation.Evidence reviewA search was conducted of level I through IV studies from January 2000 to August 2017, to identify studies reporting on talus OCDs treated with bone marrow stimulation. 21 articles were identified. The overall quality of evidence was fair.Findings21 articles were included in which 1303 ankles with OCD of talus were evaluated. Patients were assessed at a median follow-up period of 38.1 months, ranging from 6.3 to 217 months. Considering a cut-off of an area <1.5 cm2 or with a diameter ≤1.5 cm, the mean postoperative AOFAS (American Orthopaedic Foot and Ankle Society) value was 89.1±3 and 84.65±2.7, respectively (p=0.016).Conclusions and relevanceDespite the current lack of high-level evidence, our results suggest that bone marrow stimulation techniques provide an effective and reliable means to treat small to mid-sized OCD. Arthroscopic bone marrow stimulation for isolated osteochondral lesions of the talus is a safe and effective procedure that provides good clinical outcomes for lesions with an area less than 1.5 cm2 or with a diameter less than 1.5 cm. The attempt to find a new cut-off value to identify more precisely good outcome lesions was unsuccessful. However, the long-term benefits of bone marrow stimulation techniques should be tested in larger cohort of patients with longer term evaluations.Level of evidenceSystematic review, level III.
APA, Harvard, Vancouver, ISO, and other styles
12

Lauterbach, Stefan, Emmanuel Chapron, Achim Brauer, Matthias Hüls, Adrian Gilli, Fabien Arnaud, Andrea Piccin, et al. "A sedimentary record of Holocene surface runoff events and earthquake activity from Lake Iseo (Southern Alps, Italy)." Holocene 22, no. 7 (January 17, 2012): 749–60. http://dx.doi.org/10.1177/0959683611430340.

Full text
Abstract:
This study presents a record of Holocene surface runoff events and several large earthquakes, preserved in the sediments of pre-Alpine Lake Iseo, northern Italy. A combination of high-resolution seismic surveying, detailed sediment microfacies analysis, non-destructive core-scanning techniques and AMS 14C dating of terrestrial macrofossils was used to detect and date these events. Based on this approach, our data shed light on past seismic activity in the vicinity of Lake Iseo and the influence of climate variability and human impact on allochthonous detrital matter flux into the lake. The 19 m long investigated sediment sequence of faintly layered lake marl contains frequent centimetre- to decimetre-scale sandy-silty detrital layers. During the early to mid Holocene, these small-scale detrital layers, reflecting sediment supply by extreme surface runoff events, reveal a distinct centennial-scale recurrence pattern. This is in accordance with regional lake-level highstands and minima in solar activity and thus apparently mainly climate-controlled. After c. 4200 cal. yr BP, intervals of high detrital flux occasionally also correlate with periods of enhanced human settlement activity. In consequence, deposition of small-scale detrital layers during the late Holocene apparently reflects a rather complex interplay between climatic and anthropogenic influences on catchment erosion processes. Besides the small-scale detrital layers, five up to 2.40 m thick large-scale detrital event layers, composed of basal mass-wasting deposits overlain by large-scale turbidites, were identified, which are supposed to be triggered by strong earthquakes. The uppermost large-scale event layer can be correlated to a documented Mw=6.0 earthquake in ad 1222 in Brescia. The four other large-scale event layers are supposed to correspond to previously undocumented local earthquakes. These occurred around 350 bc, 570 bc, 2540 bc and 6210 bc and most probably also reached magnitudes in the order of Mw = 5.0–6.5.
APA, Harvard, Vancouver, ISO, and other styles
13

Gestel, Joannes Van. "Developments in elite level Thai boxing in Belgium: has there been a civilising influence?" International Sports Studies 41, no. 2 (February 12, 2019): 32–54. http://dx.doi.org/10.30819/iss.41-2.03.

Full text
Abstract:
This paper analyses the changes in the elite level of Thai Boxing in Belgium from the mid-1980s by employing the concept of ‘sportization’. This analysis demonstrates that there has been a small development towards the condemnation of violence and an increase in the number of weight categories which support an argument in favour of the sportization process, while a reduction of the minimum participation age suggests a counter trend. Although clear changes have been identified for other combat sports, the relative immobility of Thai Boxing is due to the diversified figurational network involving the Belgian Thai Boxing Federation. On the one hand, the federation seeks recognition from the public and the international federations representing the official sports organisations, which requires a visually attractive and safe sport. On the other hand, it also attracts those interested and inspired by its more dangerous physical characteristics. Despite the ambiguity of these findings it is argued that Thai Boxing has undergone a slight sportization process. As the rules and regulations applied in Belgium have always adhered to those of the international federation, it is likely that the results can be seen as reflecting the sport’s development in other nations.
APA, Harvard, Vancouver, ISO, and other styles
14

Bhatta, Gopal Datt, and Werner Doppler. "Spatial Distribution of Farm-Family Resources in the Mid-Hills of Nepal." Asian Journal of Agriculture and Development 8, no. 2 (December 15, 2011): 43–59. http://dx.doi.org/10.37801/ajad2011.8.2.4.

Full text
Abstract:
The location of farm households along the spatial gradient affects resource availability and farmers’ livelihoods. Many socioeconomic variables have strong spatial affinity that would otherwise be overlooked by data aggregation at household levels. The Geographic Information System (GIS) displays and analyzes socioeconomic data that could aid many social researchers in understanding socioeconomic reality influenced by geographical positions. This paper aims to integrate socioeconomic data into a GIS environment. It examines spatial tendencies of farm-family resources in the mid-hills of Nepal using spatial and random sampling techniques. Farmers living in relatively flat lands and nearby urban centers have small families, higher level of education, farm and family income. In addition, they have small agricultural holdings and engage in commercial farming. Meanwhile, the opposite applies to farmers living in the hills. These spatial differences are related mainly to road, market, and other infrastructure that are crucial for agricultural development and livelihood enhancement. Strong spatial trend in socioeconomic aspects and farm-family resource availability infer the need to focus development activities spatially.
APA, Harvard, Vancouver, ISO, and other styles
15

Gooch, James L., and Douglas S. Glazier. "TEMPORAL AND SPATIAL PATTERNS IN MID-APPALACHIAN SPRINGS." Memoirs of the Entomological Society of Canada 123, S155 (1991): 29–49. http://dx.doi.org/10.4039/entm123155029-1.

Full text
Abstract:
AbstractThe major topographic features and river courses of the mid-Appalachian Mountains are geologically ancient. Small rheocrenes are numerous in carbonate valleys with macroinvertebrate assemblages typically dominated by peracaridans and sometimes gastropods, with subordinate abundances of bivalves, triclads, and insects. Springs were approximately rank ordered by temporal persistence, using size, catchment area, proximity to base level, and bedrock permeability factors as criteria. A 38-m2 rheocrene, Ell Spring, was sampled seasonally over a 2-year period for distribution and abundances of taxa. Physicochemical factors and rank order of ordinal abundances were stable the 1st year, but less so the 2nd year after a watercress cover was removed. Ell Spring is divided into nine distinct habitat patches. Some species distributions are strongly associated with patches and others are broader. Regionally, heterozygosity and allele frequency patterns of Gammarus minus (Amphipoda) are conditioned by latitude, indicative of the effects of Pleistocene glaciation, and by distance to regional master streams. These factors do not detectably influence the ordinal composition of macroinvertebrate assemblages. However overall invertebrate abundances and the ratio of non-insect orders (which are presumably less rapid colonists) to insect orders are greater in long-persisting than in frequently disturbed springs. The species assemblages of disturbed springs may be influenced by recent history as well as by water chemistry, substratum, and other equilibrium factors.
APA, Harvard, Vancouver, ISO, and other styles
16

Semelbauer, Marek, Jozef Oboňa, Marek Barta, Barbara Mangová, and Milan Kozánek. "Spatial distribution and seasonal dynamics of non-biting moth flies (Diptera, Psychodidae) in confound conditions of a stable." Polish Journal of Entomology 89, no. 4 - Ahead of print (December 31, 2020): 190–99. http://dx.doi.org/10.5604/01.3001.0014.4974.

Full text
Abstract:
Many small Diptera adopted at some level endophilic life style, including man-made buildings. Stables create a specific type of microhabitat, which provides shady and relatively humid conditions in combination with excess of organic matter. Unlike the parasites (mosquitos, biting midges, etc.), the commensal fauna of stables is poorly studied. Moth flies (Psychodidae) were collected in cow stable located in Šenkvice, SW Slovakia. Special traps (derived from Malaise traps) were installed along the stable internal wall and in three different heights. In total, we recorded 6325 moth flies belonging to 8 species. The flight period lasted from spring to autumn. Seasonal dynamics was strongly influenced by rainfall and mean week temperature, e.g. high temperature in mid-summer caused drop in moth flies captures. The moth flies clearly preferred the ground and moderately preferred the interior of stable.
APA, Harvard, Vancouver, ISO, and other styles
17

Ding, Carl-Philipp, David Vuilleumier, Namho Kim, David L. Reuss, Magnus Sjöberg, and Benjamin Böhm. "Effect of engine conditions and injection timing on piston-top fuel films for stratified direct-injection spark-ignition operation using E30." International Journal of Engine Research 21, no. 2 (September 5, 2019): 302–18. http://dx.doi.org/10.1177/1468087419869785.

Full text
Abstract:
Mid-level ethanol/gasoline blends can provide knock resistance benefits for stoichiometric spark-ignition engine operation, but previous studies have identified challenges associated with spray impingement and wall wetting, leading to excessive particulate matter emissions. At the same time, stratified-charge spark-ignition operation can provide increased thermal efficiency, but care has to be exercised to avoid excessive in-cylinder soot formation. In support of the use of mid-level ethanol/gasoline blends in advanced spark-ignition engines, this study presents spray and fuel-film measurements in a direct-injection spark-ignition engine operated with a 30 vol.%/70 vol.% ethanol/gasoline blend (E30). Crank-angle resolved fuel-film measurements at the piston surface are conducted using two different implementations of the refractive index matching technique. A small-angle refractive index matching implementation allows quantification of the wetted area, while a large-angle refractive index matching implementation enables semi-quantitative measurements of fuel-film thickness and volume, in addition to fuel-film area. The fuel-film measurements show that both the amount of fuel deposited on the piston and the shape of the fuel-film patterns are strongly influenced by the injection timing, duration, intake pressure, and coolant temperature. For combinations of high in-cylinder gas density and long injection duration, merging of the individual spray plumes, commonly referred to as spray collapse, can cause a dramatic change to the shape and thickness of the wall fuel films. Overall, the study provides guidance to engine designers aiming at minimizing wall wetting through tailored combinations of injection timings and durations.
APA, Harvard, Vancouver, ISO, and other styles
18

Hoffmann, Lars, Alison W. Grimsdell, and M. Joan Alexander. "Stratospheric gravity waves at Southern Hemisphere orographic hotspots: 2003–2014 AIRS/Aqua observations." Atmospheric Chemistry and Physics 16, no. 14 (July 28, 2016): 9381–97. http://dx.doi.org/10.5194/acp-16-9381-2016.

Full text
Abstract:
Abstract. Stratospheric gravity waves from small-scale orographic sources are currently not well-represented in general circulation models. This may be a reason why many simulations have difficulty reproducing the dynamical behavior of the Southern Hemisphere polar vortex in a realistic manner. Here we discuss a 12-year record (2003–2014) of stratospheric gravity wave activity at Southern Hemisphere orographic hotspots as observed by the Atmospheric InfraRed Sounder (AIRS) aboard the National Aeronautics and Space Administration's (NASA) Aqua satellite. We introduce a simple and effective approach, referred to as the “two-box method”, to detect gravity wave activity from infrared nadir sounder measurements and to discriminate between gravity waves from orographic and other sources. From austral mid-fall to mid-spring (April–October) the contributions of orographic sources to the observed gravity wave occurrence frequencies were found to be largest for the Andes (90 %), followed by the Antarctic Peninsula (76 %), Kerguelen Islands (73 %), Tasmania (70 %), New Zealand (67 %), Heard Island (60 %), and other hotspots (24–54 %). Mountain wave activity was found to be closely correlated with peak terrain altitudes, and with zonal winds in the lower troposphere and mid-stratosphere. We propose a simple model to predict the occurrence of mountain wave events in the AIRS observations using zonal wind thresholds at 3 and 750 hPa. The model has significant predictive skill for hotspots where gravity wave activity is primarily due to orographic sources. It typically reproduces seasonal variations of the mountain wave occurrence frequencies at the Antarctic Peninsula and Kerguelen Islands from near zero to over 60 % with mean absolute errors of 4–5 percentage points. The prediction model can be used to disentangle upper level wind effects on observed occurrence frequencies from low-level source and other influences. The data and methods presented here can help to identify interesting case studies in the vast amount of AIRS data, which could then be further explored to study the specific characteristics of stratospheric gravity waves from orographic sources and to support model validation.
APA, Harvard, Vancouver, ISO, and other styles
19

RIDHA, M., S. FONNA, S. HUZNI, and A. K. ARIFFIN. "CORROSION RISK ASSESSMENT OF PUBLIC BUILDINGS AFFECTED BY THE 2004 TSUNAMI IN BANDA ACEH." Journal of Earthquake and Tsunami 07, no. 01 (March 2013): 1350004. http://dx.doi.org/10.1142/s1793431113500048.

Full text
Abstract:
Banda Aceh region has a coastal environment and frequent earthquakes. The 2004 Sumatra tsunami caused many buildings to collapse and became submerged by seawater in the region. Thus, the buildings might become susceptible to corrosion, which will reduce their strength. Consequently, sudden failure might happen when even a small earthquake occurs. This study reports a corrosion risk assessment for some reinforced concrete (RC) public buildings in Banda Aceh region in order to understand how the tsunami has influenced the corrosion risk level. The assessment was performed by using half-cell potential mapping technique. Six buildings were chosen: three existing buildings, two newly constructed buildings in the tsunami-affected area and one building located outside that area. The assessments were carried out from 2009 until mid of 2010. The assessment results indicated that the corrosion risk to the existing buildings were at intermediate to severe level. In addition, newly developed buildings were at intermediate level, while outside building was still at low levels. Those findings showed that the RC buildings around the tsunami-affected area, either existing or new buildings, had become corrosive. Therefore, it is important to conduct regular corrosion assessments to prevent early failure due to the coexistence of rebar corrosion and earthquake.
APA, Harvard, Vancouver, ISO, and other styles
20

Ndui, Augustus, L. Kasonka, and B. Vwalika. "Determinants of small for gestational age among HIV exposed infants delivered at the Women and Newborn hospital, Lusaka, Zambia." Medical Journal of Zambia 49, no. 1 (August 5, 2022): 42–47. http://dx.doi.org/10.55320/mjz.49.1.984.

Full text
Abstract:
Objectives: To explore the factors that influence small for gestational age outcome among HIV exposed infants delivered at the Women and Newborn Hospital, Lusaka, Zambia. Materials and Methods: This was a facility-based unmatched case control study nested in the Zambia Preterm Birth Prevention Study (ZAPPS) conducted at the Women and Newborn Hospital in Lusaka district between October 2017 and February 2021. Convenience sampling was used to select all the 53 HIV exposed small for gestational age infants (as cases) and 152 HIV unexposed small for gestational age infants (as controls). An excel data extraction tool was used to extract categorised variables from the ZAPPS data set into Stata version 19. Chi-square test was used to test for association, foetal and maternal variables with a p-value of 0.2 at univariate analyses were entered into a multiple logistic regression model. Results: The proportion of SGA, though not statistically significant, was found to be 19.9% among the HIV exposed infants compared to 17.3% in the unexposed group (p= 0.34). More than three quarters of participants in both the HIV positive arm (71.7%) and HIV negative arm (81.3%) were aged between 20-35 years. On multivariate analysis, Maternal chronic illness [AOR: 4.39, 95% CI: (1.66 - 11.6), p=0.003] and spontaneous preterm delivery [AOR: 1.58, 95% CI: (1.02 - 2.46), p=0.040] had a strong association with small for gestational age. Tertiary Level of education [AOR: 0.45, (0.24 - 0.85), p=0.014] was found to be significantly protective against small for gestational age. Maternal factors such as married status [AOR: 0.74, (0.48 - 1.13), p=0.164], secondary level of education [AOR: 0.82, (0.54 - 1.24), p=0.743], history of stillbirth [AOR: 1.31, (0.92-1.85), p=0.123] and the Mid-upper arm circumference [AOR: 0.96, (0.92-1.00), p=0.064] was not associated with small for gestational age. Conclusion: There was no association between maternal HIV infection and SGA. Maternal chronic illness and spontaneous preterm birth increase the odds of SGA outcome while tertiary level of education is protective. Further research is needed to broaden the evidence base for addressing small for gestational age as a gateway to improve perinatal mortality, and for policy implementers to devise cost-effective and sustainable ways of reaching the at-risk population.
APA, Harvard, Vancouver, ISO, and other styles
21

Ndui, Augustus, L. Kasonka, and B. Vwalika. "Determinants of small for gestational age among HIV exposed infants delivered at the Women and Newborn hospital, Lusaka, Zambia." Medical Journal of Zambia 49, no. 1 (August 5, 2022): 42–47. http://dx.doi.org/10.55320/mjz.49.1.24.

Full text
Abstract:
Objectives: To explore the factors that influence small for gestational age outcome among HIV exposed infants delivered at the Women and Newborn Hospital, Lusaka, Zambia. Materials and Methods: This was a facility-based unmatched case control study nested in the Zambia Preterm Birth Prevention Study (ZAPPS) conducted at the Women and Newborn Hospital in Lusaka district between October 2017 and February 2021. Convenience sampling was used to select all the 53 HIV exposed small for gestational age infants (as cases) and 152 HIV unexposed small for gestational age infants (as controls). An excel data extraction tool was used to extract categorised variables from the ZAPPS data set into Stata version 19. Chi-square test was used to test for association, foetal and maternal variables with a p-value of 0.2 at univariate analyses were entered into a multiple logistic regression model. Results: The proportion of SGA, though not statistically significant, was found to be 19.9% among the HIV exposed infants compared to 17.3% in the unexposed group (p= 0.34). More than three quarters of participants in both the HIV positive arm (71.7%) and HIV negative arm (81.3%) were aged between 20-35 years. On multivariate analysis, Maternal chronic illness [AOR: 4.39, 95% CI: (1.66 - 11.6), p=0.003] and spontaneous preterm delivery [AOR: 1.58, 95% CI: (1.02 - 2.46), p=0.040] had a strong association with small for gestational age. Tertiary Level of education [AOR: 0.45, (0.24 - 0.85), p=0.014] was found to be significantly protective against small for gestational age. Maternal factors such as married status [AOR: 0.74, (0.48 - 1.13), p=0.164], secondary level of education [AOR: 0.82, (0.54 - 1.24), p=0.743], history of stillbirth [AOR: 1.31, (0.92-1.85), p=0.123] and the Mid-upper arm circumference [AOR: 0.96, (0.92-1.00), p=0.064] was not associated with small for gestational age. Conclusion: There was no association between maternal HIV infection and SGA. Maternal chronic illness and spontaneous preterm birth increase the odds of SGA outcome while tertiary level of education is protective. Further research is needed to broaden the evidence base for addressing small for gestational age as a gateway to improve perinatal mortality, and for policy implementers to devise cost-effective and sustainable ways of reaching the at-risk population.
APA, Harvard, Vancouver, ISO, and other styles
22

Turashvili, Nino, Lali Javashvili, and Elene Giorgadze. "“Vitamin D Deficiency Is More Common in Women with Autoimmune Thyroiditis: A Retrospective Study”." International Journal of Endocrinology 2021 (August 17, 2021): 1–6. http://dx.doi.org/10.1155/2021/4465563.

Full text
Abstract:
Background. Vitamin D is a hormone that is mainly produced in the skin upon ultraviolet B radiation exposure and has important influence on various organs. In recent years, data have been collected that vitamin D deficiency plays an important role in the development of various nonskeletal diseases, including autoimmune diseases. Chronic autoimmune thyroiditis (Hashimoto’s thyroiditis) is one of the most common organ-specific autoimmune endocrine diseases. It is characterized by increased level of antithyroid peroxidase and/or antithyroglobulin antibodies in blood, which often leads to thyroid dysfunction and structural changes of the gland. There is an opinion that vitamin D deficiency may be considered as an important risk factor for development of chronic autoimmune thyroiditis, but data of various small studies are controversial. Despite the fact that Georgia is a sunny country, vitamin D deficiency is a widespread problem here. Thyroid diseases, including the chronic autoimmune thyroiditis, are also very common in Georgia. The aim of our research was to compare the level of vitamin D between the patients with chronic autoimmune thyroiditis and the healthy subjects. Methods. This retrospective study enrolled subjects, who were 18–70 years old and visited the clinics “Cortex” and “National Institute of Endocrinology” in 2018 or in 2019 from mid-spring to mid-summer. Data of thyroid-stimulating hormone, free thyroxine, antithyroid peroxidase antibodies, antithyroglobulin antibodies, thyroid ultrasonography, and 25(OH) vitamin D were retrospectively analysed based on medical history. In total, data of 1295 patients were collected. The statistical processing of data was performed through the SPSS 20 program. Results. The negative association between thyroid-stimulating hormone, antithyroid peroxidase antibodies, antithyroglobulin antibodies, heterogeneous parenchyma of thyroid gland, and vitamin D was found in women. Statistically significant association was not detected in men. Conclusions. Serum vitamin D is lower in women with autoimmune thyroiditis and primary hypothyroidism. Further studies are needed to evaluate the influence of vitamin D supplementation on thyroid autoantibody positivity or primary hypothyroidism.
APA, Harvard, Vancouver, ISO, and other styles
23

Ramelli, Fabiola, Jan Henneberger, Robert O. David, Annika Lauber, Julie T. Pasquier, Jörg Wieder, Johannes Bühl, et al. "Influence of low-level blocking and turbulence on the microphysics of a mixed-phase cloud in an inner-Alpine valley." Atmospheric Chemistry and Physics 21, no. 6 (April 1, 2021): 5151–72. http://dx.doi.org/10.5194/acp-21-5151-2021.

Full text
Abstract:
Abstract. Previous studies that investigated orographic precipitation have primarily focused on isolated mountain barriers. Here we investigate the influence of low-level blocking and shear-induced turbulence on the cloud microphysics and precipitation formation in a complex inner-Alpine valley. The analysis focuses on a mid-level cloud in a post-frontal environment and a low-level feeder cloud induced by an in-valley circulation. Observations were obtained from an extensive set of instruments including ground-based remote sensing instrumentation, in situ instrumentation on a tethered-balloon system and ground-based precipitation measurements. During this event, the boundary layer was characterized by a blocked low-level flow and enhanced turbulence in the region of strong vertical wind shear at the boundary between the blocked layer in the valley and the stronger cross-barrier flow aloft. Cloud radar observations indicated changes in the microphysical cloud properties within the turbulent shear layer including enhanced linear depolarization ratio (i.e., change in particle shape or density) and increased radar reflectivity (i.e., enhanced ice growth). Based on the ice particle habits observed at the surface, we suggest that riming, aggregation and needle growth occurred within the turbulent layer. Collisions of fragile ice crystals (e.g., dendrites, needles) and the Hallett–Mossop process might have contributed to secondary ice production. Additionally, in situ instrumentation on the tethered-balloon system observed the presence of a low-level feeder cloud above a small-scale topographic feature, which dissipated when the low-level flow turned from a blocked to an unblocked state. Our observations indicate that the low-level blocking (due to the downstream mountain barrier) created an in-valley circulation, which led to the production of local updrafts and the formation of a low-level feeder cloud. Although the feeder cloud did not enhance precipitation in this particular case (since the majority of the precipitation sublimated when falling through a subsaturated layer above), we propose that local flow effects such as low-level blocking can induce the formation of feeder clouds in mountain valleys and on the leeward slope of foothills upstream of the main mountain barrier, where they can act to enhance orographic precipitation through the seeder–feeder mechanism.
APA, Harvard, Vancouver, ISO, and other styles
24

Wang, Kan, Ahmed El-Mowafy, Weijin Qin, and Xuhai Yang. "Integrity Monitoring of PPP-RTK Positioning; Part I: GNSS-Based IM Procedure." Remote Sensing 14, no. 1 (December 23, 2021): 44. http://dx.doi.org/10.3390/rs14010044.

Full text
Abstract:
Nowadays, integrity monitoring (IM) is required for diverse safety-related applications using intelligent transport systems (ITS). To ensure high availability for road transport users for in-lane positioning, a sub-meter horizontal protection level (HPL) is expected, which normally requires a much higher horizontal positioning precision of, e.g., a few centimeters. Precise point positioning-real-time kinematic (PPP-RTK) is a positioning method that could achieve high accuracy without long convergence time and strong dependency on nearby infrastructure. As the first part of a series of papers, this contribution proposes an IM strategy for multi-constellation PPP-RTK positioning based on global navigation satellite system (GNSS) signals. It analytically studies the form of the variance-covariance (V-C) matrix of ionosphere interpolation errors for both accuracy and integrity purposes, which considers the processing noise, the ionosphere activities and the network scale. In addition, this contribution analyzes the impacts of diverse factors on the size and convergence of the HPLs, including the user multipath environment, the ionosphere activity, the network scale and the horizontal probability of misleading information (PMI). It is found that the user multipath environment generally has the largest influence on the size of the converged HPLs, while the ionosphere interpolation and the multipath environments have joint impacts on the convergence of the HPL. Making use of 1 Hz data of Global Positioning System (GPS)/Galileo/Beidou Navigation Satellite System (BDS) signals on L1 and L5 frequencies, for small- to mid-scaled networks, under nominal multipath environments and for a horizontal PMI down to 2×10−6, the ambiguity-float HPLs can converge to 1.5 m within or around 50 epochs under quiet to medium ionosphere activities. Under nominal multipath conditions for small- to mid-scaled networks, with the partial ambiguity resolution enabled, the HPLs can converge to 0.3 m within 10 epochs even under active ionosphere activities.
APA, Harvard, Vancouver, ISO, and other styles
25

Grose, Michael R., Mitchell T. Black, Guomin Wang, Andrew D. King, Pandora Hope, and David J. Karoly. "The warm and extremely dry spring in 2015 in Tasmania contained the fingerprint of human influence on the climate." Journal of Southern Hemisphere Earth Systems Science 69, no. 1 (2019): 183. http://dx.doi.org/10.1071/es19011.

Full text
Abstract:
Tasmania saw a warm and very dry spring and summer in 2015–16, including a record dry October, which had significant, wide-ranging impacts. A previous study using two probabilistic event-attribution techniques found a small but statistically significant increase in the likelihood of the record dry October due to anthropogenic influence. Given the human signal was less clear amid natural variability for rainfall compared to temperature extremes, here we provided further evidence and context for this finding. An additional attribution method supported the October rainfall finding, and the median attributable risk to human influence in the three methods was ~25%, 48% and 75%. The results suggested that human influence on rainfall was partly through increased sea level pressure in the mid-latitudes associated with fewer rainbearing systems, a circulation driver that was consistent with recent trends that have been attributed to human influence. Dry conditions were also driven by a positive Indian Ocean Dipole and El Niño at the time, but this study could not reliably estimate the effect of human influence on these phenomena, as each model gave a different estimate of the ocean warming pattern. Along with rainfall, attribution modelling showed a role for human influence in higher temperature and evaporation through October 2015, as well as a high drought index throughout spring. Confidence in the attribution of a human signal on this extreme dry event increased as multiple attribution methods agreed, a plausible atmospheric circulation driver was identified, and temperature and evaporation also showed an anthropogenic signal.
APA, Harvard, Vancouver, ISO, and other styles
26

Hetzel, Yasha, Ivica Janekovic, and Charitha Pattiaratchi. "BENEFITS AND LIMITATIONS OF A COUPLED WAVE-SURGE MODEL FOR AUSTRALIAN EXTREMES." Coastal Engineering Proceedings, no. 36v (December 28, 2020): 49. http://dx.doi.org/10.9753/icce.v36v.waves.49.

Full text
Abstract:
Extreme sea levels result from a combination of a range of factors that include long term mean sea level variability, astronomical tides, storm surges due to atmospheric pressure and wind, wave breaking, and other regional dynamics. Numerical circulation/storm-surge models are frequently used to predict water levels over broad areas with the outputs used for planning or emergency management applications. Recently, coupled wave-circulation models have been shown to improve extreme sea level predictions through the inclusion of wave setup that results from the transfer of momentum of breaking waves into sea level at the shoreline. Other studies have shown that the representations of surface wind drag can be improved when the sea state is considered, and this can directly influence the amplitude of storm surges at the coast. However, most coupled wave-circulation model studies have been undertaken for relatively small computational domains and for a limited range of coastal morphologies and storm types. In this paper we assess the benefits and limitations of using a coupled wave-circulation model to predict extreme sea levels and determine wave effects for a broad range of coastal morphologies and extreme storm events all around Australia. Simulated events occurred in three oceans and considered tropical cyclones, a cyclone undergoing extratropical transition, and a large mid-latitude extratropical low-pressure system.Recorded Presentation from the vICCE (YouTube Link): https://youtu.be/UfyWHI4OHBA
APA, Harvard, Vancouver, ISO, and other styles
27

Thompson, S. P., A. Herlihy, C. A. Murray, A. R. Baker, S. J. Day, A. J. Smith, and T. Snow. "Amorphous Mg–Fe silicates from microwave-dried sol–gels." Astronomy & Astrophysics 624 (April 2019): A136. http://dx.doi.org/10.1051/0004-6361/201834691.

Full text
Abstract:
Context. Laboratory analogues can provide physical constraints to the interpretation of astronomical observations of cosmic dust but clearly do not experience the same formation conditions. To distinguish between properties intrinsic to the material and properties imprinted by their means of formation requires extensive characterisation. Aims. Sol–gel methods can produce amorphous silicates with potentially high reproducibility, but often require long drying times (24+ h) at elevated temperatures in air, controlled atmosphere, or vacuum. We investigate the possibility that microwave drying can be used to form amorphous silicate on a timescale of ∼10 min and characterise their structural and spectroscopic properties relative to silicates produced by other drying methods. Methods. Microwave-dried amorphous MgSiO3, Fe0.1Mg0.9SiO3 and Mg2SiO4 are characterised using X-ray powder diffraction, total X-ray scattering, small angle X-ray scattering and mid-IR FTIR spectroscopy, and compared to samples produced from the same gels but dried in-air and under vacuum. The development of crystalline structure in the microwave-dried silicates via thermal annealing up to 999°C is also investigated using in situ X-ray powder diffraction. Results. At the inter-atomic level the silicate structures are largely independent of drying method, however larger-scale structured domains, ranging from a ∼few × 10 Å to ∼100’s Å in size, are observed. These are ordered as mass fractals with discernible variation caused by the drying processes. The mid-IR 10 μm band profile is also found to be influenced by the drying process, likely due to the way removal of water and bonded OH influences the distribution of tetrahedral species. However, microwave drying also allows Fe to be easily incorporated into the silicate structure. In situ annealing shows that for amorphous MgSiO3 crystalline forsterite, enstatite and cristobalite are high temperature phases, while for Mg2SiO4 forsterite crystallises at lower temperatures followed by cristobalite at high temperature. For Fe0.1Mg0.9SiO3 the crystallisation temperature is significantly increased and only forsterite is observed. Crystalline SiO2 may be diagnostic of Mg-rich, Fe-poor grain mineralogies. The results are discussed in relation to the different thermal conditions required for dust to crystallise within protoplanetary disk lifetimes. Conclusions. Sol–gel microwave drying provides a fast and easy method of producing amorphous Mg- and Fe,Mg-silicates of both pyroxene and olivine compositions. Their structure and spectroscopic characteristics although similar to silicates produced using other drying methods, exhibit subtle variations which are particularly manifest spectroscopically in the mid-IR, and structurally over medium- and long-range length scales.
APA, Harvard, Vancouver, ISO, and other styles
28

Vitt, Dale H. "AN OVERVIEW OF FACTORS THAT INFLUENCE THE DEVELOPMENT OF CANADIAN PEATLANDS." Memoirs of the Entomological Society of Canada 126, S169 (1994): 7–20. http://dx.doi.org/10.4039/entm126169007-1.

Full text
Abstract:
AbstractCanadian peatlands can be classified into ombrotrophic bogs and minerotrophic fens, the latter subdivided into poor, moderate-rich, and extreme-rich fens, each with distinctive indicator species, acidity, alkalinity, and base cation content. If hydrology is considered the most important factor in peatland classification then the primary division must be between ombrotrophic bogs and minerotrophic fens; however both chemical and vegetational differences strongly indicate that the primary division of peatlands should be between acidic, Sphagnum-dominated bogs and poor fens on the one hand, and alkaline, brown-moss-dominated rich fens on the other. Although some metals such as sulphur and aluminum also vary along this gradient, nutrient contents of the surface waters do not. Bogs and fens are oligotrophic to mesotrophic wetlands that should be distinguished from eutrophic, non-peat-forming wetlands such as marshes and swamps by the presence in the former of a well-developed ground layer of bryophytes associated with relatively little seasonal water level fluctuation. Oligotrophy is probably maintained in bogs and poor fens by reduced water flow, whereas rich fens maintain mesotrophy by having larger water through-puts; however this is not well documented. Sphagnum appears to have real ecological significance, both in the initial stages of acidification and in controlling surface water temperature. Seasonal variation in surface water chemistry in all peatland types is relatively small, however precipitation events leading to changes in water levels do affect some chemical components. Although both autogenic and allogenic factors affect peatland development, initiation of peat formation and early development of peatlands during the Early and Mid Holocene were considerably influenced by regional climatic change. Later developmental patterns during the late Holocene and those seen at the present time appear to be more influenced by autogenic factors.
APA, Harvard, Vancouver, ISO, and other styles
29

Zhou, Wencang, Zhu Zhu, and Donald Vredenburgh. "Emotional intelligence, psychological safety, and team decision making." Team Performance Management: An International Journal 26, no. 1/2 (March 12, 2020): 123–41. http://dx.doi.org/10.1108/tpm-10-2019-0105.

Full text
Abstract:
Purpose As teamwork becomes more prevalent in organizational decision-making, the influence of emotional intelligence (EI) on team decision-making process demands more research attention. This study aims to investigate the impact of EI on team psychological safety and decision-making performance. Design/methodology/approach Team decision-making performance and decision quality from a team decision task were obtained from 54 decision-making teams composed of 241 undergraduate business students from a Mid-Atlantic university. Regression analyses were used to test individual and team’s EI relationship with team decision performance and the mediation effect of psychological safety. Findings This study provides empirical evidence that individual EI is positively related to individual influence on team decisions. Team-level EI improves team decision-making performance through increases in psychological safety. Research limitations/implications The sample size is relatively small, and the participants were business students; therefore, the research results may lack generalizability. Future research is encouraged to explore this topic further. Practical implications As teamwork becomes more prevalent in organizational decision-making, the influence of EI on team decision-making process demands more research and managerial attention. The findings of this paper provide insights on the importance of individual/team EI and psychological safety in team decision performance. Originality/value This study furthers research showing that emotions are pertinent to social interactions, including group decision-making, and therefore suggests the desirability of investigating other social processes affecting group decision-making.
APA, Harvard, Vancouver, ISO, and other styles
30

Liu, Xiaobo, Hai Chu, Jun Sun, Wei Zhao, and Qingtao Meng. "A Numerical Simulation of the Development Process of a Mesoscale Convection Complex Causing Severe Rainstorm in the Yangtze River Delta Region behind a Northward Moving Typhoon." Atmosphere 13, no. 3 (March 14, 2022): 473. http://dx.doi.org/10.3390/atmos13030473.

Full text
Abstract:
In recent years, due to the influence of global warming, extreme weather events occur frequently, such as the continuous heavy precipitation, regional high temperature, super typhoon, etc. Tropical cyclones make frequent landfall, heavy rains and flood disasters caused by landfall typhoons have a huge impact, and typhoon rainstorms are often closely related to mesoscale and small-scale system activities. The application 2020 NCEP (National Centers for Environmental Prediction) final operational global analysis data and WRF (Weather Research and Forecasting model, version 3.9) mesoscale numerical prediction model successfully simulates the evolution characteristics of the mesoscale convective complex (MCC) that caused an extreme rainstorm in the Yangtze River delta region behind a northwards typhoon in this article. The results show that a meso-β-scale vortex existed in the mid- to upper troposphere in the region where the MCC occurred; accompanied by the occurrence of the meso-β-scale vortex, the convective cloud clusters developed violently, and its shape is a typical vortex structure. The simulation-sensitive experiment shows that the development of the meso-β-scale cyclonic vortex is the main reason for the enhancement of MCC. The occurrence and development of the MCC is manifested as a vertical positive vorticity column and a strong vertical ascending motion region in the dynamic field. In the development and maturity stage of the MCC, the vorticity and vertical rising velocity in the MCC area are significantly greater than those in the weakened typhoon circulation, which shows significant mesoscale convective system characteristics. The diagnostic analysis of the vorticity equation shows that the positive vorticity advection caused by the meso-β-scale cyclonic vortex in the mid- to upper troposphere plays important roles in the development of the MCC. Enhanced low-level convergence enhances vertical ascending motion. The convective latent heat release also plays an important role on the development of the MCC, changes the atmospheric instability by heating, enhances the upward movement, and delivers positive vorticity to the upper level, making the convection develop higher, forming a positive feedback mechanism between low-level convergence and high-level divergence. The simulation-sensitive experiment also shows that the meso-β-scale cyclonic vortex formation in this process is related to convective latent heat release.
APA, Harvard, Vancouver, ISO, and other styles
31

Elsaman, Hosam Azat, Nourhan El-Bayaa, and Suriyakumaran Kousihan. "Measuring and Validating the Factors Influenced the SME Business Growth in Germany—Descriptive Analysis and Construct Validation." Data 7, no. 11 (November 10, 2022): 158. http://dx.doi.org/10.3390/data7110158.

Full text
Abstract:
In Germany, the medical device industry constitutes a cornerstone of the health sector. In this study, we investigated the challenges and factors affecting the present-day performance of German SMEs concerned with medical devices. The research methodology adopted a cross-sectional and correlational research design, with simple random-sampling techniques, to data obtained from 110 mid-level and senior managers in German SMEs by means of an online structured survey in August 2022. We statistically validated our study data using exploratory factor analysis (EFA), Kaiser–Meyer–Olkin (KMO) testing, and Bartlett’s test, to assess the relationship between study variables and measure data adequacy using the R4.1.1(21) software, then carried out principal component analysis (PCA) with varimax factor loading and extracted six factors for use as research variables. The researchers also applied descriptive data analysis techniques using SPSS.21. The main study variables were: (1) the business performance of small and medium businesses (SMP); (2) their financial situation (SMEF); and (3) their implementation of new medical device industry regulations (MDR). By such statistical means, results confirmed poorer business performance and lower anticipated growth amongst SMEs affected by MDR, over and above the impacts of the present-day economic situation. The data can be used by management information systems (MIS) and decision system support professionals for planning and developing practical models about how to cope with current industry challenges. We recommend further research involving inferential analysis and triangulation of these data in the form of a semi-structured qualitative study in the larger scope of the population and different sectors.
APA, Harvard, Vancouver, ISO, and other styles
32

O Ericson, M., A. Bratt, R. Nisell, G. Németh, and J. Ekholm. "Load moments about the hip and knee joints during ergometer cycling." Journal of Rehabilitation Medicine 18, no. 4 (August 6, 2020): 165–72. http://dx.doi.org/10.2340/16501977198618165172.

Full text
Abstract:
The aim of the study was to calculate the magnitudes of moments of force acting about the bilateral hip and knee joint axes during ergometer cycling. Six healthy subjects pedalled a weight-braked bicycle ergometer at different workloads, pedalling rates, saddle heights and pedal foot position. During cycling at 120 Watts, 60 revolutions per minute with mid-saddle height and anterior pedal foot position, the mean peak flexing and extending hip load moments were 34.3 and 8.9 Nm, respectively. Mean peak flexing knee load moments was 28.8 Nm and extending moment was 11.9 Nm. Hip load moments were significantly increased by increasing the ergometer workload or pedalling rate. For knee load moments, workload was the most important factor. The flexing knee load moment did not change with changes in pedalling rate. Different saddle heights or pedal food positions had a slight but not always statistically significant influence on the hip and knee joint loads. The maximum hip and knee joint load moments induced during cycling were small compared with those obtained during other exercises or normal activities such as level walking, stair climbing, and lifting.
APA, Harvard, Vancouver, ISO, and other styles
33

Beever, D. E., M. S. Dhanoa, H. R. Losada, R. T. Evans, S. B. Cammell, and J. France. "The effect of forage species and stage of harvest on the processes of digestion occurring in the rumen of cattle." British Journal of Nutrition 56, no. 2 (September 1986): 439–54. http://dx.doi.org/10.1079/bjn19860124.

Full text
Abstract:
1. Pure swards of perennial ryegrass (Lolium perenne L. cv. Melle) or white clover (Trifolium repens L. cv. Blanca) were harvested daily as either primary growth (May-June) or mid- (July) and late- (August-September) season 4-week regrowths and offered to Friesian steers at two levels of feed allowance (18 and 24 g dry matter (DM)/kg live weight), to examine the effect of forage species and stage of harvest on nutrient digestion and supply.2. The early- and mid-season grasses had low nitrogen (23 g/kg DM) and high water-soluble carbohydrate (169 g/kg) contents whilst the late-season grass had a higher N content (28 g/kg). All clover diets had high N (average 45 g/kg) and low water-soluble carbohydrate (89 g/kg) contents, and DM digestibility on all diets ranged from 0.77 to 0.83 (mean of two feeding levels).3. Mean total rumen volatile fatty acid concentrations were significantly (P < 0.001) higher on the clover diets, whilst on the grass diets molar proportions of propionate showed a slight but not significant decline with advancing season and tended to be higher than those on the clover diets. Mean rumen ammonia concentrations were significantly (P < 0.001) lower on the early- and mid-season grasses (59 mg NH3-N/1) than the late-season grass (242 mg/l) and early-season clover (283 mg/l) which were all significantly (P < 0.01) lower than the mid-and late-season clovers (372 and 590 mg/l) respectively.4. Rates of organic matter (OM) and N digestion in the rumen were estimated using established nylon-bag techniques and found to be high on all diets, but significant effects due to forage species (clover > grass; P < 0.001) were detected, whilst overall potential degradability in the rumen exceeded 0.89 for both OM and N on all diets.5. Significantly (P < 0.001) more OM entered the small intestine of calves fed on white clover (10.2 g/kg live weight) than those fed on ryegrass (8.33 g/kg) and similar effects due to level of feeding (g/kg; low 7.9, high 10.6; P < 0.05) and stage of harvest (g/kg; early 8.3 v. mid 10.0, late 9.50; P < 0.05) were also detected. Non-NH3-N (NAN) flow (g/kg) to the small intestine was increased by forage species (grass 0.56, clover 0.69; P < 0.05) and stage of harvest (early 0.59 v. mid 0.65, late 0.64; P > 0.05) whilst NAN flow/N intake ranged from 0.96 to 1.65 g/g (mean 1.25) on the grass diets and from 0.64 to 0.84 g/g (mean 0.75) on the clovers (P < 0001).6. Microbial N flow to the small intestine averaged 0.72 of duodenal NAN (grass 0.76, clover 0.69). Efficiency of microbial N synthesis was high on all diets, (g/kg OM truly digested in the rumen; grass 33.5, clover 36.3), as was the estimated extent of in vivo feed N degradation (g/g N intake; grass 0.75, clover 0.79).7. A model is described to simulate the progress curves of the ratio, degraded N:degraded OM in the rumen for the six diets, using indices obtained in the present study. The results are ratified with the in vivo observations of N utilization in the rumen for the grass and clover diets.8. It is concluded that both forage species and stage of harvest can significantly influence the processes of rumen digestion and nutrient supply, but with the fresh forages examined in the present study, it would appear that the processes of digestion in the rumen greatly outweighed the passage of potentially digestible nutrients from the rumen.
APA, Harvard, Vancouver, ISO, and other styles
34

Stacey, Dennis W., Masahiro Hitomi, and Guan Chen. "Influence of Cell Cycle and Oncogene Activity upon Topoisomerase IIα Expression and Drug Toxicity." Molecular and Cellular Biology 20, no. 24 (December 15, 2000): 9127–37. http://dx.doi.org/10.1128/mcb.20.24.9127-9137.2000.

Full text
Abstract:
ABSTRACT The cell cycle, oncogenic signaling, and topoisomerase (topo) IIα levels all influence sensitivity to anti-topo II drugs. Because the cell cycle and oncogenic signaling influence each other as well as topo IIα levels, it is difficult to assess the importance of any one of these factors independently of the others during drug treatment. Such information, however, is vital to an understanding of the cellular basis of drug toxicity. We, therefore, developed a series of analytical procedures to individually assess the role of each of these factors during treatment with the anti-topo II drug etoposide. All studies were performed with asynchronously proliferating cultures by the use of time-lapse and quantitative fluorescence staining procedures. To our surprise, we found that neither oncogene action nor the cell cycle altered topo IIα protein levels in actively cycling cells. Only a minor population of slowly cycling cells within these cultures responded to constitutively active oncogenes by elevating topo IIα production. Thus, it was possible to study the effects of the cell cycle and oncogene action on drug-treated cells while topo IIα levels remained constant. Toxicity analyses were performed with two consecutive time-lapse observations separated by a brief drug treatment. The cell cycle phase was determined from the first observation, and cell fate was determined from the second. Cells were most sensitive to drug treatment from mid-S phase through G2 phase, with G1 phase cells nearly threefold less sensitive. In addition, the presence of an oncogenicsrc gene or microinjected Ras protein increased drug toxicity by approximately threefold in actively cycling cells and by at least this level in the small population of slowly cycling cells. We conclude that both cell cycle phase and oncogenic signaling influence drug toxicity independently of alterations in topo IIα levels.
APA, Harvard, Vancouver, ISO, and other styles
35

Blanchard, P. J., C. C. Warkup, M. Ellis, M. B. Willis, and P. Avery. "The influence of the proportion of Duroc genes on growth, carcass and pork eating quality characteristics." Animal Science 68, no. 3 (April 1999): 495–501. http://dx.doi.org/10.1017/s1357729800050505.

Full text
Abstract:
AbstractA study was carried out involving 721 pigs, comprising boars and gilts, with either 0, 0.25 , or 0.50 Duroc inclusion level, which were produced by mating Large White boars with Large White × British Landrace sows, Large White boars with Duroc × (Large White × British Landrace) sows, or Duroc boars with Large White × British Landrace sows, respectively. Animals were reared on one of seven different feeding regimens from 30 to 90 kg live weight. Tissue growth rates were determined using a triple sampling procedure based on a combination of full-side and ham joint dissection on subsamples of pigs (127 and 366 pigs, respectively) and P2 backfat thickness on the remainder. Initial body composition was determined at 30 kg on subsamples of the three genotypes. Daily food intakes increased with increasing Duroc inclusion but live-weight gains were similar for the three genotypes. Lean and fat growth rates and food conversion ratios were greatest for the 0·50 Duroc group, although the genotype differences were small. Killing-out proportions and P2 fat depths were higher for the 0.25 and 0·50 Duroc groups. The proportion of lean in the carcass was lower (P < 0·01) for 0·50 Duroc pigs. Japanese colour scores and EEL reflectance indicated that the longissimus muscle was darker for the 0·25 and 0·50 Duroc genotypes. Subcutaneous fat firmness scores and penetrometer readings taken in the mid back indicated softer fat for the 0 Duroc group. Intramuscular fat levels increased (P < 0·01) with increasing Duroc inclusion (10.4, 11.2, and 18·2 g/kg for the 0, 0.25, and 0.50 groups respectively). Cooked longissimus from pigs with 0·50 Duroc had a lower shear force and was judged to have a stronger pork odour and to be more tender and acceptable than that from the 0 Duroc group. The 0.25 Duroc group showed a small improvement in tenderness but a weaker pork odour and similar overall acceptability compared with the 0 Duroc group. This study suggests that the use of the Duroc in crossing systems in the United Kingdom will have limited impact on growth performance but that 0·50 Duroc inclusion will result in fatter carcasses, higher intramuscular fat levels and improved eating quality.
APA, Harvard, Vancouver, ISO, and other styles
36

Johnson, Richard H., Steven L. Aves, Paul E. Ciesielski, and Thomas D. Keenan. "Organization of Oceanic Convection during the Onset of the 1998 East Asian Summer Monsoon." Monthly Weather Review 133, no. 1 (January 1, 2005): 131–48. http://dx.doi.org/10.1175/mwr-2843.1.

Full text
Abstract:
Abstract The organizational modes of convection over the northern South China Sea (SCS) during the onset of the summer monsoon are documented using radar and sounding data from the May–June 1998 South China Sea Monsoon Experiment (SCSMEX). The onset occurred in mid-May with a rapid increase in deep convection over a 10-day period, accompanied by a major shift in the circulation over the east Asian region. Analysis of Bureau of Meteorology Research Centre (BMRC) radar data from Dongsha Island reveals a wide range of organizational modes of convection over the northern SCS. Proximity sounding data indicate that lower- and middle-level vertical wind shears exerted a dominant control over the orientation of convective lines within mesoscale convective systems in this region, as has been found in the Australian monsoon region and the equatorial western Pacific. The results are consistent with the conceptual model of LeMone et al. based on the Tropical Ocean Global Atmosphere Coupled Ocean–Atmosphere Response Experiment (TOGA COARE), except two new organizational modes have been identified: shear-parallel bands for strong low-level shear and weak midlevel shear when there is weak instability and the air is dry aloft, and shear-parallel bands for strong shears in both layers when the shear vectors are in the same direction. Midlatitude influences, namely, the passage of troughs over southern China, likely contributed to these two additional modes. The stratiform rain fraction from the convective systems during the monsoon onset period was relatively small (26%) compared to the estimated average of about 40% for the entire Tropics. This small fraction is attributed to the weak instability during the onset period and relatively dry air in the upper troposphere.
APA, Harvard, Vancouver, ISO, and other styles
37

Murugesu, John, and Chandra Sakaran. "The Interaction of Market Risk and Idiosyncratic Risk on Equity Mutual Fund Returns." International Journal of Financial Research 10, no. 6 (August 8, 2019): 1. http://dx.doi.org/10.5430/ijfr.v10n6p1.

Full text
Abstract:
This study examines the importance of idiosyncratic and systematic risks in explaining equity fund returns in Malaysia. The level of market and idiosyncratic risk in a mutual fund depends on what asset class it invests in. Equity type asset classes are exposed to both systematic and idiosyncratic risk but research generally suggest that only systematic risk is relevant in mutual fund selection since idiosyncratic risk can be reduced through fund diversification. This study attempts to expand the insights of the risk-return relationship by providing additional evidence on the direct and indirect effects of investment risk on equity mutual fund returns. Employing partial least squares structural equation modelling (PLS-SEM), we also explore if idiosyncratic risk moderates the relationship between market risk and mutual fund returns. A sample of 150 Malaysian domestic equity mutual funds comprising of large, mid & small-cap equity funds were selected from the Morningstar website. The results indicate that market risk does not influence mutual funds returns but idiosyncratic risk has a significant and positive effect. Idiosyncratic risk is proxied by fund characteristics comprising of size, age, expenses and fund manager ability. This study shows that fund size, age or expenses are not significant and only the fund alpha which measures fund manager ability is relevant in predicting fund returns. The study also finds that the fund alpha moderates the influence of market risk on returns by changing the nature of the relationship from positive to negative.
APA, Harvard, Vancouver, ISO, and other styles
38

Lyons, Betsy, Nalini M. Nadkarni, and Malcolm P. North. "Spatial distribution and succession of epiphytes on Tsuga heterophylla (western hemlock) in an old-growth Douglas-fir forest." Canadian Journal of Botany 78, no. 7 (July 1, 2000): 957–68. http://dx.doi.org/10.1139/b00-064.

Full text
Abstract:
We examined the distribution and abundance of nonvascular epiphytes on western hemlock trees in an old-growth coniferous forest focusing on patterns of epiphyte distribution at different spatial scales, epiphyte abundance amongst trees differing in size, and crown structures associated with epiphyte abundance. Total epiphyte cover was greatest in four canopy microhabitats: the upper canopy strata, crowns of large trees, lower crown branches, and inner branch plots. Epiphyte functional groups were stratified vertically within the stand and horizontally within branches. Alectorioid and "other" lichens were most abundant in the upper canopy and outer branch plots. Cyanolichens and Sphaerophorus globosus (Huds.) Vain. were most abundant in the lower to mid canopy. Although cyanolichens were most abundant in middle branch plots, Sphaerophorus was most abundant in inner branch plots. Bryophytes were most abundant in the lower canopy and inner branch plots. At the stand level, canopy height and tree size were the main influences on epiphytes. Within trees, plots closer to the tree trunk and lower in the crown had the greatest abundance of epiphytes. In this forest, understory trees were colonized first by bryophytes, not by alectorioid and "other" lichens as is common for small trees in young stands.Key words: epiphyte succession, lichens, western hemlock, old growth, forest canopy, crown structure.
APA, Harvard, Vancouver, ISO, and other styles
39

Luo, Hongying, and Ran Tao. "Prediction of the Cavitation over a Twisted Hydrofoil Considering the Nuclei Fraction Sensitivity at 4000 m Altitude Level." Water 13, no. 14 (July 13, 2021): 1938. http://dx.doi.org/10.3390/w13141938.

Full text
Abstract:
Cavitation phenomenon is important in hydraulic turbomachineries. With the construction of pumping stations and hydro power stations on plateau, the influence of nuclei fraction on cavitation becomes important. As a simplified model, a twisted hydrofoil was used in this study to understand the cavitation behaviors on pump impeller blade and turbine runner blade at different altitude levels. The altitudes of 0 m, 1000 m, 2000 m, 3000 m and 4000 m were comparatively studied for simulating the plateau situation. Results show that the cavitation volume proportion fcav increases with the decreasing of cavitation coefficient Cσ. At a specific Cσ, high altitude and few nuclei will cause smaller size of cavitation. The smaller Cσ is, the higher the sensitivity Δfcav is. The larger Cσ is, the higher the relative sensitivity Δfcav* is. On the twisted foil, flow incidence angle increases from the sidewall to mid-span with the decreasing of the local minimum pressure. When Cσ is continually decreasing, the size of cavitation extends in spanwise, streamwise and thickness directions. The cavity is broken by the backward-jet flow when Cσ becomes small. A tail generates and the cavity becomes relatively unstable. This study will provide reference for evaluating the cavitation status of the water pumps and hydroturbines installed on a plateau with high altitude level.
APA, Harvard, Vancouver, ISO, and other styles
40

Liang, Linda, and Guangzheng Yu. "Effect of spatial separation of sources on speech intelligibility in an automotive environment." Journal of the Acoustical Society of America 152, no. 4 (October 2022): A42. http://dx.doi.org/10.1121/10.0015478.

Full text
Abstract:
Speech intelligibility has been shown to be enhanced when the target speech source is spatially separated from the interferer, which is related to the spatial unmasking phenomenon. However, this issue has not been studied in the small acoustical space of an automobile. This study, thus, examines the effect of spatial separation of sources on the speech reception threshold (SRT) in an automobile, and compared with the results in a weak-reflective listening room. The target was always presented at the front-passenger seat, and the interferer was presented at the front-passenger seat, right-back seat, mid-back seat, and left-back seat in sequence. The stimuli were synthesized using convolution with binaural room impulse responses measured on a dummy head in driver seat under different interferer locations. Sentence SRTs in Mandarin Chinese were measured via headphones virtually in an automobile and a listening room. Accordingly, the spatial release from masking (SRM) was obtained based on the SRT result. Results show that the SRM in automobile is always smaller than that in listening room, because the early reflections and seat-back occlusions cannot only obscure the binaural cues related to the source localization such as the interaural-time-difference and interaural-level-difference, but also influence the target-to-interferer ratio.
APA, Harvard, Vancouver, ISO, and other styles
41

Schwarz, Tomasz, Marcin Kopyra, and Jacek Nowicki. "Physiological mechanisms of ovarian follicular growth in pigs — A review." Acta Veterinaria Hungarica 56, no. 3 (September 1, 2008): 369–78. http://dx.doi.org/10.1556/avet.56.2008.3.10.

Full text
Abstract:
Follicular growth after antrum formation is determined by follicle-stimulating hormone (FSH). Only two ways are possible for recruited follicles, continuing development or atresia. In gilts, intensive ovarian follicular growth begins between 60 and 100 days of age, and fluctuations of the ovarian morphological status last about 20 days; however, at that time there are no really large follicles. Final follicular development is under luteinising hormone (LH) control; this is why the attainment of puberty is related to an increase in serum oestradiol to a level that causes a preovulatory surge of this gonadotropin. The pool of follicles at the beginning of the oestrous cycle is about 30–40, most of which are small (< 3 mm) and growing. Then, the pool of follicles increases to about 80 in the mid-luteal phase but about 50 of them are small and 30 are medium sized (3–6.9 mm). Some of these follicles are in the growing phase, but some are atretic. Between days 7 and 15 of the oestrous cycle the percentage of atretic follicles fluctuates between 12 and 73%. At that time there are no large (> 7 mm) follicles because of the suppressing effect of progesterone. The number of small follicles declines after luteolysis. From the pool of medium follicles, large follicles are selected under the influence of LH, but about 70% of the medium-sized follicles become atretic. Because of the long-lasting selection process there is a significant heterogeneity in the diameter of large follicles in oestrus. However, the number of follicles correlates with the number of corpora lutea after ovulation. Individual follicular development and the relationship between follicles are still poorly known. The use of ultrasonography may give a closer insight into these phenomena.
APA, Harvard, Vancouver, ISO, and other styles
42

Camp, Charles D., and Ka-Kit Tung. "The Influence of the Solar Cycle and QBO on the Late-Winter Stratospheric Polar Vortex." Journal of the Atmospheric Sciences 64, no. 4 (April 1, 2007): 1267–83. http://dx.doi.org/10.1175/jas3883.1.

Full text
Abstract:
Abstract A statistical analysis of 51 years of NCEP–NCAR reanalysis data is conducted to isolate the separate effects of the 11-yr solar cycle (SC) and the equatorial quasi-biennial oscillation (QBO) on the Northern Hemisphere (NH) stratosphere in late winter (February–March). In a four-group [SC maximum (SC-max) versus minimum (SC-min) and east-phase versus west-phase QBO] linear discriminant analysis, the state of the westerly phase QBO (wQBO) during SC-min emerges as a distinct least-perturbed (and coldest) state of the stratospheric polar vortex, statistically well separated from the other perturbed states. Relative to this least-perturbed state, the SC-max and easterly QBO (eQBO) each independently provides perturbation and warming as does the combined perturbation of the SC-max–eQBO. All of these results (except the eQBO perturbation) are significant at the 95% confidence level as confirmed by Monte Carlo tests; the eQBO perturbation is marginally significant at the 90% level. This observational result suggests a conceptual change in understanding the interaction between solar cycle and QBO influences: while previous results imply a more substantial interaction, even to the extent that the warming due to SC-max is reversed to cooling by the eQBO, results suggest that the SC-max and eQBO separately warm the polar stratosphere from the least-perturbed state. While previous authors emphasize the importance of segregating the data according to the phase of the QBO, here the same polar warming by the solar cycle is found regardless of the phase of the QBO. The polar temperature is positively correlated with the SC, with a statistically significant zonal mean warming of approximately 4.6 K in the 10–50-hPa layer in the mean and 7.2 K from peak to peak. This magnitude of the warming in winter is too large to be explainable by UV radiation alone. The evidence seems to suggest that the polar warming in NH late winter during SC-max is due to the occurrence of sudden stratospheric warmings (SSWs), as noted previously by other authors. This hypothesis is circumstantially substantiated here by the similarity between the meridional pattern and timing of the warming and cooling observed during the SC-max and the known pattern and timing of SSWs, which has the form of large warming over the pole and small cooling over the midlatitudes during mid- and late winter. The eQBO is also known to precondition the polar vortex for the onset of SSWs, and it has been pointed out by previous authors that SSWs can occur during eQBO at all stages of the solar cycle. The additional perturbation due to SC-max does not double the frequency of occurrence of SSWs induced by the eQBO. This explains why the SC-max/eQBO years are not statistically warmer than either the SC-max/wQBO or SC minimum/eQBO years. The difference between two perturbed (warm) states (e.g., SC-max/eQBO versus SC-min/eQBO or SC-max/eQBO versus SC-max/wQBO), is small (about 0.3–0.4 K) and not statistically significant. It is this small difference between perturbed states, both warmer than the least-perturbed state, that in the past has been interpreted either as a reversal of SC-induced warming or as a reversal of QBO-induced warming.
APA, Harvard, Vancouver, ISO, and other styles
43

Wang, Zhuo, Yuxuan Ma, Guangming Kan, Baohua Liu, Xinghua Zhou, and Xiaobo Zhang. "An Inversion Method for Geoacoustic Parameters in Shallow Water Based on Bottom Reflection Signals." Remote Sensing 15, no. 13 (June 23, 2023): 3237. http://dx.doi.org/10.3390/rs15133237.

Full text
Abstract:
The inversion method based on the reflection loss-grazing angle curve is an effective tool to obtain local underwater acoustic parameters. Because geoacoustic parameters vary in sensitivity to grazing angle, it is difficult to get accurate results in geoacoustic parameter inversion based on small-grazing-angle data in shallow water. In addition, the normal-mode model commonly used in geoacoustic parameter inversion fails to meet the needs of accurate local sound field simulation as the influence of the secant integral is ignored. To solve these problems, an acoustic data acquisition scheme was rationally designed based on a sparker source, a fixed vertical array, and ship drifting with the swell, which could balance the trade-off among signal transmission efficiency and signal stability, and the actual local acoustic data at low-to-mid frequencies were acquired at wide grazing angles in the South Yellow Sea area. Furthermore, the bottom reflection coefficients (bottom reflection losses) corresponding to different grazing angles were calculated based on the wavenumber integration method. The local seafloor sediment parameters were then estimated using the genetic algorithm and the bottom reflection loss curve with wide grazing angles, obtaining more accurate local acoustic information. The seafloor acoustic velocity inverted is cp=1659 m/s and the sound attenuation is αp=0.656 dB/λ in the South Yellow Sea. Relevant experimental results indicate that the method described in this study is feasible for local inversion of geoacoustic parameters for seafloor sediments. Compared with conventional large-scale inversion methods, in areas where there are significant changes in the seabed sediment level, this method can obtain more accurate local acoustic features within small-scale areas.
APA, Harvard, Vancouver, ISO, and other styles
44

Vakharia, Neville, Marilena Vecco, Andrej Srakar, and Divya Janardhan. "Knowledge centricity and organizational performance: an empirical study of the performing arts." Journal of Knowledge Management 22, no. 5 (June 11, 2018): 1124–52. http://dx.doi.org/10.1108/jkm-06-2017-0219.

Full text
Abstract:
PurposeThis paper explores the concepts of knowledge-centric organizations in the performing arts sector to understand how specific organizational practices relate to measures of financial and operational performance.Design/methodology/approachA quantitative analysis of 368 small and mid-sized nonprofit performing arts organizations in the USA was undertaken via primary data on organizational practices and secondary data on performance metrics. Structural equation modeling was used to validate the latent construct of knowledge centricity and to test hypotheses on how knowledge centricity impacts financial and operational performance, and is influenced by firm-level demographic variables.FindingsResults show several distinct performance metrics that are statistically associated with knowledge-centric practices of the organizations analyzed.Research limitations/implicationsThis article investigates the knowledge centricity of organizations, a relatively nascent theoretical concept, which is of significant relevance in today’s knowledge-driven economy. The findings can serve as a basis to further investigate strategic approaches that arts organizations can undertake to remain sustainable and operate effectively in a knowledge-driven society.Practical/implicationsIt provides critical insights into management practices and approaches that can be instituted to drive improved organizational performance.Originality/valueBuilding on the extant literature, this article develops a conceptual framework of knowledge centricity and defines a knowledge-centric organization. It thoroughly investigates the latent construct of knowledge centricity, identifies how knowledge centricity impacts financial and operational performance of nonprofit performing arts organizations, and provides grounding for future studies.
APA, Harvard, Vancouver, ISO, and other styles
45

Murphy, E. J., R. D. Cavanagh, K. F. Drinkwater, S. M. Grant, J. J. Heymans, E. E. Hofmann, G. L. Hunt, and N. M. Johnston. "Understanding the structure and functioning of polar pelagic ecosystems to predict the impacts of change." Proceedings of the Royal Society B: Biological Sciences 283, no. 1844 (December 14, 2016): 20161646. http://dx.doi.org/10.1098/rspb.2016.1646.

Full text
Abstract:
The determinants of the structure, functioning and resilience of pelagic ecosystems across most of the polar regions are not well known. Improved understanding is essential for assessing the value of biodiversity and predicting the effects of change (including in biodiversity) on these ecosystems and the services they maintain. Here we focus on the trophic interactions that underpin ecosystem structure, developing comparative analyses of how polar pelagic food webs vary in relation to the environment. We highlight that there is not a singular, generic Arctic or Antarctic pelagic food web, and, although there are characteristic pathways of energy flow dominated by a small number of species, alternative routes are important for maintaining energy transfer and resilience. These more complex routes cannot, however, provide the same rate of energy flow to highest trophic-level species. Food-web structure may be similar in different regions, but the individual species that dominate mid-trophic levels vary across polar regions. The characteristics (traits) of these species are also different and these differences influence a range of food-web processes. Low functional redundancy at key trophic levels makes these ecosystems particularly sensitive to change. To develop models for projecting responses of polar ecosystems to future environmental change, we propose a conceptual framework that links the life histories of pelagic species and the structure of polar food webs.
APA, Harvard, Vancouver, ISO, and other styles
46

Prider, Jane N., and David C. Christophel. "Distributional ecology of Gymnostoma australianum (Casuarinaceae), a putative palaeoendemic of Australian wet tropic forests." Australian Journal of Botany 48, no. 4 (2000): 427. http://dx.doi.org/10.1071/bt99006.

Full text
Abstract:
The small, tropical Australian rainforest tree Gymnostoma australianum (L. Johnson) is presently only known from five sites in the environs of Thornton Peak, in north-eastern Queensland. Aggregated populations of these trees occur in open sites along rocky stream banks at various altitudes from sea level to 1200 m, and amongst granite outcrops and fern fields at high altitudes. Trees are tolerant of shallow, acidic soils but do not occur where light is limiting. The population of trees occurring on a mid-stream island in Noah Creek form monospecific stands on the central rocky portion of the island. This population is subject to moderate levels of disturbance during flooding. Lost individuals are likely to be replaced by conspecifics as seedling growth under adults is plentiful. Although disturbance enables current populations to persist, the species does not appear to be a coloniser of disturbed habitats. Gymnostoma australianum is more accurately described as a habitat specialist, occurring in marginal, low nutrient sites within various types of rain forest. These sites are narrow in range both geographically and ecologically. This restricts the expansion of current populations and has probably influenced population expansion in the past. Therefore, the hypothesis that the species, or its ancestor, was a recent immigrant from northern tropical Malesian forests was rejected. The current distribution of the species is more likely to represent the persistence and expansion of trees from local refugia.
APA, Harvard, Vancouver, ISO, and other styles
47

Powell, John H., Abdulkader M. Abed, and Yves-Michel Le Nindre. "Cambrian stratigraphy of Jordan." GeoArabia 19, no. 3 (July 1, 2014): 81–134. http://dx.doi.org/10.2113/geoarabia190381.

Full text
Abstract:
ABSTRACT The lower and middle Cambrian succession (Ram Group) in Jordan is described in lexicon-style format to document an important phase of Earth history following the uplift and erosion of the Arabian-Nubian Shield (Aqaba Complex) during the late Neoproterozoic, and younger, but more localised, intrusive and volcanic/volcaniclastic activity that formed the Araba Complex. The early Cambrian Ram Unconformity (ca. 530 Ma) marks the base of a predominantly fluvial siliciclastic succession derived from rapidly eroding Neoproterozoic (including Ediacaran) basement rocks, but includes a brief, but biostratigraphically significant, sequence of marine siliciclastics and carbonates, the early mid-Cambrian Burj Formation. Rapid uplift and erosion of the granitoid basement (Arabian-Nubian Shield or ANS) resulted in a peneplanation of the Aqaba Complex over millions of years duration (latest Neoproterozoic to Cambrian) in the Southern Desert of Jordan. Early Cambrian pebbly sandstones and locally derived conglomerates (Salib Formation) were deposited on an alluvial plain by high velocity-high discharge, northward flowing (NNE to NNW) braided rivers, characterised by trough cross-bedding and erosive tabular sets. Brief, and rare, marine influence is represented, locally, by thin Skolithos-burrowed sandstones. A regional sea-level rise in the early mid-Cambrian marks a major marine transgressive-regressive cycle and southward thinning carbonate-siliciclastic wedge (Burj Formation) widely present in the subsurface across the Arabian Platform. During deposition of this transgressive marine sequence the palaeoshoreline was oriented WNW-ESE in southern Jordan. The transgressive phase (TST) is represented by tidal-dominated siltstones and fine-grained sandstones (Tayan Member) containing a diverse Cruziana/Rusophycus ichnofaunal assemblage. The overlying carbonate unit (Numayri Member) represents the highstand (HST) and maximum marine flooding surface (MFS), and comprises a carbonate ramp sequence of shelly wackestone, packstone and grainstone with ooids and oncolites, and a diverse shelly fauna including trilobites, brachiopods and hyolithids. A return to regressive tidal-influenced sandstone and siltstone (along with thin carbonates in central Jordan) (Hanneh Member) represents a regressive wedge (RST) deposited in response to renewed uplift of the ANS. Trilobites, represented by the Kingaspis campbelli and Redlichops faunules, suggest a biostratigraphical age of early mid-Cambrian for the carbonate MFS, which equates approximately to the base of the Cambrian Series 3 (Stage 5). This event probably represents the Cambrian marine flooding surface Cm20 (approximate geochronological age of 509 to 505 Ma). South of Feinan, in the Wadi Araba, the carbonates pass laterally to marine sandstone (Abu Khusheiba Sandstone) with extensive Skolithos burrows and Cruziana/Rusophycus traces. Traced southwards (palaeohinterland) the marine influence diminishes, so that the Burj/Abu Khusheiba units are absent in the Southern Desert. Ediacaran intrusives, together with extrusive volcanic and volcaniclastic rocks (Araba Complex) are associated with rifting and half-graben formation in the Feinan-Petra area. This later tectonic activity produced a younger (Ediacaran to early Cambrian), immature palaeotopography, in marked contrast to the Neoproterozoic Aqaba Complex peneplain in the Southern Desert. Consequently, early and mid-Cambrian fluvial and shallow-marine siliciclastics (Salib and Abu Khusheiba formations) onlap progressively onto this immature palaeotopography that was subsequently buried by mid-Cambrian time. Increased basinal subsidence to the north of the Araba Complex ‘high’ provided increased accommodation space that resulted in the deposition of a thick sandstone succession in north Jordan. The Feinan-Petra region seems to have acted as an east-west hinge-line with greater subsidence of the Arabian Platform to the north; similar thickness trends are seen in the Burj and Umm Ishrin formations. Renewed uplift and erosion of the ANS to the south led to deposition of a thick succession of fluvial-dominated sands, again deposited by large-scale braided rivers (Umm Ishrin Formation). Fluvial sedimentation continued through mid to late Cambrian times and also the Ordovician (Disi and Umm Sahm formations), but episodic shallow-marine or estuarine flooding of the low-gradient alluvial plain resulted in colonisation, locally, by arthropods and annelid worms that produced a diverse and abundant Cruziana/Rusophycus/Planolites assemblage of tentative Floian (Arenig) age (upper Disi Formation). Overall the Cambrian to Ordovician Ram Group siliciclastics (Salib-Umm Ishrin-Disi-Umm Sahm formations) show an upward increase in sand maturity from arkose (Salib) to orthoquartzite (Disi); heavy-mineral signatures (ZTR), specifically datable zircons, indicate provenance from a predominantly distant Neoproterozoic granitoid source rock area located to the south (ANS) that was undergoing intensive weathering. However, a small zircon component was derived from older pre-Neoproterozoic rocks, consistent with the general trend in the Levant. The highly permeable Cambrian siliciclastics of Jordan and surrounding countries provide an important regional aquifer, the Ram (formerly Disi) Aquifer. In a suitable setting these reservoir rocks might have potential for hydrocarbon exploration where source rocks of Neoproterozoic, Silurian or Permian age are faulted and in proximity, at depth, in the central Arabian Platform.
APA, Harvard, Vancouver, ISO, and other styles
48

Gai, Yan, Janet L. Ruhland, and Tom C. T. Yin. "Effects of forward masking on sound localization in cats: basic findings with broadband maskers." Journal of Neurophysiology 110, no. 7 (October 1, 2013): 1600–1610. http://dx.doi.org/10.1152/jn.00255.2013.

Full text
Abstract:
Forward masking is traditionally measured with a detection task in which the addition of a preceding masking sound results in an increased signal-detection threshold. Little is known about the influence of forward masking on localization of free-field sound for human or animal subjects. Here we recorded gaze shifts of two head-unrestrained cats during localization using a search-coil technique. A broadband (BB) noise masker was presented straight ahead. A brief signal could come from 1 of the 17 speaker locations in the frontal hemifield. The signal was either a BB or a band-limited (BL) noise. For BB targets, the presence of the forward masker reduced localization accuracy at almost all target levels (20 to 80 dB SPL) along both horizontal and vertical dimensions. Temporal decay of masking was observed when a 15-ms interstimulus gap was added between the end of the masker and the beginning of the target. A large effect of forward masking was also observed for BL targets with low (0.2–2 kHz) and mid (2–7 kHz) frequencies, indicating that the interaural timing cue is susceptible to forward masking. Except at low sound levels, a small or little effect was observed for high-frequency (7–15 kHz) targets, indicating that the interaural level and the spectral cues in that frequency range remained relatively robust. Our findings suggest that different localization mechanisms can operate independently in a complex listening environment.
APA, Harvard, Vancouver, ISO, and other styles
49

KIM, DONG-WON. "Yoshio Nishina and two cyclotrons." Historical Studies in the Physical and Biological Sciences 36, no. 2 (March 1, 2006): 243–73. http://dx.doi.org/10.1525/hsps.2006.36.2.243.

Full text
Abstract:
ABSTRACT Yoshio Nishina is often honored as ““a father of modern physics in Japan.”” By performing multiple roles as a competent researcher, a formidable teacher, and a shrewd organizer, he not only made a great contribution to the emergence of a research network that produced two Nobel prize winners in physics but also raised the level of Japanese physics overall. Among Nishina's many contributions to the Japanese physics community, the construction and operation of two cyclotrons during the 1930s and 1940s were the most celebrated. In this paper I try to answer the following questions: why did Nishina start the construction of two cyclotron in the mid-1930s?; how did he secure the necessary financial support?; what were the original objectives of the machines, and how were they were actually used?; what difficulties did he meet and overcome in the construction and running of the cyclotrons?; how significant was the Berkeley connection in contributing to the construction and operation of the cyclotrons?; why did Nishina skip the construction of the medium size cyclotron (30––40 inches) and move directly from a small (26-inch) to a large one (60-inch)?; and how much did the cyclotron project influence the future path of Japanese physics? I argue that Nishina's two cyclotrons, especially the larger one, should be considered as successful examples of reverse engineering, a hallmark of Japanese technology in the interwar period.
APA, Harvard, Vancouver, ISO, and other styles
50

Nehme, Eileen, Sierra Castedo de Martell, Hannah Matthews, and David Lakey. "Experiences and Perspectives on Adopting New Practices for Social Needs-targeted Care in Safety-net Settings: A Qualitative Case Series Study." Journal of Primary Care & Community Health 12 (January 2021): 215013272110177. http://dx.doi.org/10.1177/21501327211017784.

Full text
Abstract:
Introduction Clinical settings are being encouraged to identify and address patients’ social needs within the clinic or through partner organizations. The purpose of this qualitative study was to describe the current practice of social needs-targeted care in 3 Texas safety net clinics, and facilitators and barriers to adopting new social needs-targeted care tools and practices. Methods Interviews were conducted with staff at 3 safety net clinics serving small and mid-sized communities. Analysis focused on perspectives and decisions around adopting new tools or practices related to social needs-targeted care, including standardized screening tools and community resource referral platforms. Results Nine staff across 3 organizations were interviewed. Two organizations were currently using a standard social needs screening tool in their routine practice, and a third was considering doing so. One organization had adopted a community resource referral platform in partnership with a large community collaboration. Three case studies illustrate a range of facilitators, barriers, perceived benefits, and drawbacks influencing social needs-targeted practices. Benefits of systematic data collection on social needs included the generation of data for community action. Drawbacks include concerns about data privacy. Community resource referral platforms were seen as valuable for creating accountability, but required an influential community partner and adequate community resources. Concerns about disempowering clients and blurring roles were voiced, and potential to increase provider job satisfaction was identified. Conclusions Benefits and drawbacks of adopting new tools and practices related to social needs-targeted care are strongly influenced by the community context. For the adoption of community resource referral platforms, the outer setting is particularly relevant; adoption readiness is best assessed at the community or regional level rather than the clinic system level. While screening tools are much easier than referral platforms for clinics to adopt, the ability to address identified needs remains heavily based on the outer setting.
APA, Harvard, Vancouver, ISO, and other styles
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography