scholarly journals Plant functional types determine how close postfire seedlings are from their parents in a species-rich shrubland

2020 ◽  
Author(s):  
Byron B Lamont ◽  
Ed T F Witkowski
Keyword(s):  
Community Dynamics ◽  
Scale Up ◽  
Spatial Relations ◽  
Matched Pairs ◽  
Shrub Species ◽  
Data Set ◽  
Functional Types ◽  
Biological Explanation ◽  
Total Data ◽  
Adult Plants

Abstract Background and Aims Fine-scale spatial patterns of the seedlings of co-occurring species reveal the relative success of reproduction and dispersal and may help interpret coexistence patterns of adult plants. To understand whether postfire community dynamics are controlled by mathematical, biological or environmental factors, we documented seedling–adult (putative parent) distances for a range of co-occurring species. We hypothesized that nearest-seedling-to-adult distances should be a function of the distance between the closest conspecific seedlings, closest inter-adult distances and seedling-to-parent ratios, and also that these should scale up in a consistent way from all individuals, to within and between species and finally between functional types (FTs). Methods We assessed seedling–adult, seedling–seedling and adult–adult distances for 19 co-occurring shrub species 10 months after fire in a species-rich shrubland in south-western Australia. Species were categorized into 2 × 2 FTs: those that are killed by fire [non-(re)sprouters] vs. those that survive (resprouters) in nine taxonomically matched pairs, and those that disperse their seeds prefire (geosporous) vs. those that disperse their seeds postfire (serotinous). Key Results For the total data set and means for all species, seedling–adult distance was essentially a mathematical phenomenon, and correlated positively with seedling–seedling distance and adult–adult distance, and inversely with seedlings per adult. Among the four FTs, seedling–adult distance was shortest for geosporous non-sprouters and widest for serotinous resprouters. Why adults that produce few seedlings (resprouters) should be further away from them defies a simple mathematical or biological explanation at present. Ecologically, however, it is adaptive: the closest seedling was usually under the (now incinerated) parent crown of non-sprouters whereas those of resprouters were on average four times further away. Conclusions Our study highlights the value of recognizing four reproductive syndromes within fire-prone vegetation, and shows how these are characterized by marked differences in their seedling–adult spatial relations that serve to enhance biodiversity of the community.

An analysis of the safety of the single dose, two drug regimens used in programmes to eliminate lymphatic filariasis

Parasitology ◽  
2000 ◽  
Vol 121 (S1) ◽  
pp. S147-S160 ◽  
Author(s):  
J. HORTON ◽  
C. WITT ◽  
E.A. OTTESEN ◽  
J.K. LAZDINS ◽  
D.G. ADDISS ◽  
...  
Keyword(s):  
Lymphatic Filariasis ◽  
Wuchereria Bancrofti ◽  
The Philippines ◽  
Data Set ◽  
Direct Observations ◽  
National Public Health ◽  
Total Data ◽  
Drug Regimens ◽  
At Risk Populations ◽  
Health Programmes

This review of the safety of the co-administration regimens to be used in programmes to eliminate lymphatic filariasis (albendazole+ivermectin or albendazole+diethylcarbamazine [DEC]) is based on 17 studies conducted in Sri Lanka, India, Haiti, Ghana, Tanzania, Kenya, Ecuador, the Philippines, Gabon, Papua New Guinea, and Bangladesh. The total data set comprises 90635 subject exposures and includes individuals of all ages and both genders. Results are presented for hospital-based studies, laboratory studies, active surveillance of microfilaria-positive and microfilaria-negative individuals, and passive monitoring in both community-based studies and mass treatment programmes of individuals treated with albendazole (n=1538), ivermectin (9822), DEC (576), albendazole+ivermectin (7470), albendazole+DEC (69020), or placebo (1144). The most rigorous monitoring, which includes haematological and biochemical laboratory parameters pre- and post-treatment, provides no evidence that consistent changes are induced by any treatment; the majority of abnormalities appear to be sporadic, and the addition of albendazole to either ivermectin or DEC does not increase the frequency of abnormalities. Both DEC and ivermectin show, as expected, an adverse event profile compatible with the destruction of microfilariae. The addition of albendazole to either single-drug treatment regimen does not appear to increase the frequency or intensity of events seen with these microfilaricidal drugs when used alone. Direct observations indicated that the level of adverse events, both frequency and intensity, was correlated with the level of microfilaraemia. In non microfilaraemic individuals, who form 80–90% of the ‘at risk’ populations to be treated in most national public health programmes to eliminate lymphatic filariasis (LF), the event profile with the compounds alone or in combination does not differ significantly from that of placebo. Data on the use of ivermectin+albendazole in areas either of double infection (onchocerciasis and LF), or of loiais (with or without concurrent LF) are still inadequate and further studies are needed. Additional data are also recommended for populations infected with Brugia malayi, since most data thus far derive from populations infected with Wuchereria bancrofti.

scholarly journals Twitter, Telepractice, and the COVID-19 Pandemic: A Social Media Content Analysis

2021 ◽  
pp. 1-11
Author(s):  
Kristen Weidner ◽  
Joneen Lowman ◽  
Anne Fleischer ◽  
Kyle Kosik ◽  
Peyton Goodbread ◽  
...  
Keyword(s):  
Social Media ◽  
Content Analysis ◽  
Technology Implementation ◽  
Scale Up ◽  
Media Content Analysis ◽  
Data Set ◽  
Implementation Framework ◽  
Health Crisis ◽  
Wide Scale ◽  
Twitter Users

Purpose Telepractice was extensively utilized during the COVID-19 pandemic. Little is known about issues experienced during the wide-scale rollout of a service delivery model that was novel to many. Social media research is a way to unobtrusively analyze public communication, including during a health crisis. We investigated the characteristics of tweets about telepractice through the lens of an established health technology implementation framework. Results can help guide efforts to support and sustain telehealth beyond the pandemic context. Method We retrieved a historical Twitter data set containing tweets about telepractice from the early months of the pandemic. Tweets were analyzed using a concurrent mixed-methods content analysis design informed by the nonadoption, abandonment, scale-up, spread, and sustainability (NASSS) framework. Results Approximately 2,200 Twitter posts were retrieved, and 820 original tweets were analyzed qualitatively. Volume of tweets about telepractice increased in the early months of the pandemic. The largest group of Twitter users tweeting about telepractice was a group of clinical professionals. Tweet content reflected many, but not all, domains of the NASSS framework. Conclusions Twitter posting about telepractice increased during the pandemic. Although many tweets represented topics expected in technology implementation, some represented phenomena were potentially unique to speech-language pathology. Certain technology implementation topics, notably sustainability, were not found in the data. Implications for future telepractice implementation and further research are discussed.

scholarly journals Portrait of a Russian Homeschooler’s Family: Results of an Online Poll

Discourse ◽  
2021 ◽  
Vol 6 (6) ◽  
pp. 87-98
Author(s):  
M. N. Yashina
Keyword(s):  
Online Survey ◽  
Primary School Children ◽  
Family Education ◽  
Data Set ◽  
Number Of Children ◽  
Random Samples ◽  
The Social ◽  
The Family ◽  
Total Data ◽  
High Level

Introduction. The practice of obtaining family education has become a fashionable trend in our country in recent years. Despite the growing popularity among the population, we have not yet received enough scientific understanding of this form of training. The purpose of the article is to describe the social portrait of families who have chosen a family form of education for a child. The scientific novelty of the work is due to the empirical data presented in it, which have a dynamic nature of observing the studied object.Methodology and sources. The methodological basis for the study was the conflict approach and the principles of a radical humanistic approach to education in the interpretation of I. Illich. The empirical basis of the study is the results of three surveys of parents o f c hildren f rom 6 t o 1 8 y ears o ld w ho are o n f amily e ducation. S urveys w ere implemented from 2016 to 2020, according to the same methodology and tools. To collect data, a questionnaire for an online survey was developed, which was distributed on social networks, mainly in VKontakte communities dedicated to family education. The total data set includes 443 respondents.Results and discussion. According to surveys, children in family education grow up in full families, where the parent's ode has a high level of education, the mother, as a rule, does not work or has the possibility of a free schedule and is a teacher for the child. The main source of income in the family is the father. The total income of the family, which averages from 40 to 60 thousand rubles per month. In the family, most often two children, one of whom is in family education. Family education is mainly provided with primary school children.Conclusion. The peculiarity of studying family education not only in our country, but also in the world is the lack of accurate statistics on the number of children of homeschoolers. In this regard, only non-random samples are possible in the implementation. The portrait of Russian homeschoolers differs from American ones, in particular in the level at which family education is implemented, the place of residence of families, and their income.

Morphological diversification of Ptychopariida (Trilobita) from the Marjumiid biomere (Middle and Upper Cambrian)

Paleobiology ◽  
1996 ◽  
Vol 22 (1) ◽  
pp. 49-65 ◽  
Author(s):  
Frederick A. Sundberg
Keyword(s):  
Great Basin ◽  
Limited Range ◽  
Data Set ◽  
Morphological Diversification ◽  
Upper Cambrian ◽  
Causal Mechanisms ◽  
Environmental Controls ◽  
Total Data ◽  
Adaptive Radiations ◽  
Endemic Evolution

Ptychopariid trilobites from the Marjumiid biomere of Laurentia underwent a statistically significant morphological diversification that is concordant with proposed adaptive radiations of trilobites in each of the Cambrian biomeres. An analysis of a subset consisting of the biomere's most characteristic taxa, the Asaphiscacea, Raymondinacea, and Marjumiacea, also illustrates this morphological diversification. In detail, the total data set and subset show a limited range of morphologies near the base of the biomere and a large increase in range in the upper portion of the biomere.Regional assemblages from the Appalachians, Great Basin, and Texas were also studied to determine if they too show the larger-scale macroevolutionary patterns of trilobites from Laurentia as a whole. The regional assemblages illustrate similar, butnot identical, morphological diversifications, which are also similar to the overall Laurentian pattern. Subsets of the characteristic taxa also show this diversification. These results suggest that regional assemblages can be used to investigate these larger-scale macroevolutionary patterns.Causal mechanisms for the diversification patterns are not clear. Potential mechanisms include: (1) endemic evolution of new morphologies in Laurentia; (2) migration of new morphologies, including intra- and inter-continental migrations; and (3) environmental controls over the distribution of morphologies. Likely causes for the morphological diversification and its similarity among regions probably include aspects of all three mechanisms.

scholarly journals On solving large p-median problems

2019 ◽  
Vol 47 (6) ◽  
pp. 981-996
Author(s):  
Wangshu Mu ◽  
Daoqin Tong
Keyword(s):  
Big Data ◽  
Random Sampling ◽  
Computing Time ◽  
Scale Up ◽  
Problem Solution ◽  
Median Problem ◽  
Data Set ◽  
Location Models ◽  
Spatial Voting ◽  
Median Problems

Incorporating big data in urban planning has great potential for better modeling of urban dynamics and more efficiently allocating limited resources. However, big data may present new challenges for problem solutions. This research focuses on the p-median problem, one of the most widely used location models in urban and regional planning. Similar to many other location models, the p-median problem is non-deterministic polynomial-time hard (NP-hard), and solving large-sized p-median problems is difficult. This research proposes a high performance computing-based algorithm, random sampling and spatial voting, to solve large-sized p-median problems. Instead of solving a large p-median problem directly, a random sampling scheme is introduced to create smaller sub- p-median problems that can be solved in parallel efficiently. A spatial voting strategy is designed to evaluate the candidate facility sites for inclusion in obtaining the final problem solution. Tests with the Balanced Iterative Reducing and Clustering using Hierarchies (BIRCH) data set show that random sampling and spatial voting provides high-quality solutions and reduces computing time significantly. Tests also demonstrate the dynamic scalability of the algorithm; it can start with a small amount of computing resources and scale up and down flexibly depending on the availability of the computing resources.

Comparisons of Environmental Ordinations with Principal Component Vegetational Ordinations for Sets of Data Having Different Degrees of Complexity

1971 ◽  
Vol 1 (2) ◽  
pp. 99-112 ◽  
Author(s):  
J. K. Jeglum ◽  
C. F. Wehrhahn ◽  
J. M. A. Swan
Keyword(s):  
Principal Component Analysis ◽  
Water Level ◽  
Principal Component ◽  
Low Complexity ◽  
Component Analysis ◽  
Two Dimensional ◽  
High Complexity ◽  
Water Conductivity ◽  
Data Set ◽  
Total Data

Data from a survey of lowland, mainly peatland, vegetation were subjected to environmental ordination based on measurements of water level and water conductivity, and to vegetational ordination derived from principal component analysis (P.C.A.). Analyzed were the total set of the data ("all types"), half sets ("nonwoody" and "woody types") and quarter sets (stands of "marshes", "meadows", "shrub fens", and "other woody types"); the number of distinct physiognomic groups in a set of data, and presumably the amount of contained heterogeneity, decreased at each segmentation.The effectiveness of the ordination models was tested by correlating measured distances in two-dimensional ordination models with 2W/(A + B) indices of vegetational similarity for randomly selected pairs of types or stands. As the physiognomic complexity decreased, the effectiveness of the P.C.A. vegetational ordination increased whereas that of the environmental ordination decreased. The environmental ordination seemed most appropriate to the data encompassing high complexity (total data set), while the P.C.A. vegetational ordination seemed most appropriate to data with low complexity (quarter sets of the data).

scholarly journals Large-Scale Distributed Training Applied to Generative Adversarial Networks for Calorimeter Simulation

2019 ◽  
Vol 214 ◽  
pp. 06025
Author(s):  
Jean-Roch Vlimant ◽  
Felice Pantaleo ◽  
Maurizio Pierini ◽  
Vladimir Loncar ◽  
Sofia Vallecorsa ◽  
...  
Keyword(s):  
Large Scale ◽  
Message Passing Interface ◽  
Scale Up ◽  
High Energy ◽  
Neural Nets ◽  
Generative Adversarial Networks ◽  
Detector Response ◽  
Data Set ◽  
Distributed Training ◽  
Adversarial Networks

In recent years, several studies have demonstrated the benefit of using deep learning to solve typical tasks related to high energy physics data taking and analysis. In particular, generative adversarial networks are a good candidate to supplement the simulation of the detector response in a collider environment. Training of neural network models has been made tractable with the improvement of optimization methods and the advent of GP-GPU well adapted to tackle the highly-parallelizable task of training neural nets. Despite these advancements, training of large models over large data sets can take days to weeks. Even more so, finding the best model architecture and settings can take many expensive trials. To get the best out of this new technology, it is important to scale up the available network-training resources and, consequently, to provide tools for optimal large-scale distributed training. In this context, our development of a new training workflow, which scales on multi-node/multi-GPU architectures with an eye to deployment on high performance computing machines is described. We describe the integration of hyper parameter optimization with a distributed training framework using Message Passing Interface, for models defined in keras [12] or pytorch [13]. We present results on the speedup of training generative adversarial networks trained on a data set composed of the energy deposition from electron, photons, charged and neutral hadrons in a fine grained digital calorimeter.

scholarly journals Similarity between seed rain and neighbouring mature tree communities in an old-growth temperate forest

2019 ◽  
Vol 31 (6) ◽  
pp. 2435-2444
Author(s):  
Yunyun Wang ◽  
Jalene M. LaMontagne ◽  
Fei Lin ◽  
Zuoqiang Yuan ◽  
Ji Ye ◽  
...  
Keyword(s):  
Seed Dispersal ◽  
Temperate Forest ◽  
Community Dynamics ◽  
Basal Area ◽  
Seed Rain ◽  
Mature Trees ◽  
Data Set ◽  
Deposition Patterns ◽  
Tree Communities ◽  
Tree Traits

Abstract Seed distribution and deposition patterns around parent trees are strongly affected by functional traits and therefore influence the development of plant communities. To assess the limitations of seed dispersal and the extent to which diaspore and neighbouring parental traits explain seed rain, we used a 9-year seed data set based on 150 seed traps in a 25-ha area of a temperate forest in the Changbai Mountain. Among 480,598 seeds belonging to 12 families, 17 genera, and 26 species were identified, only 54% of the species with mature trees in the community were represented in seeds collected over the 9 years, indicating a limitation in seed dispersal. Understory species were most limited; overstory species were least limited. Species with wind-dispersed seed had the least limitation, while the lowest similarity in species richness was for animal-dispersed species followed by gravity-dispersed species; fleshy-fruited species had stronger dispersal limitations than dry-fruited species. Generalized linear mixed models showed that relative basal area had a significant positive effect on seed abundance in traps, while the contribution of diaspore traits was low for nearly all groups. These results suggest that tree traits had the strongest contribution to seed dispersal and deposition for all functional groups examined here. These findings strengthen the knowledge that tree traits are key in explaining seed deposition patterns, at least at the primary dispersal stage. This improved knowledge of sources of seeds that are dispersed could facilitate greater understanding of seedling and community dynamics in temperate forests.

scholarly journals Analysis of the PilQ Secretin from Neisseria meningitidis by Transmission Electron Microscopy Reveals a Dodecameric Quaternary Structure

2001 ◽  
Vol 183 (13) ◽  
pp. 3825-3832 ◽  
Author(s):  
Richard F. Collins ◽  
Linn Davidsen ◽  
Jeremy P. Derrick ◽  
Robert C. Ford ◽  
Tone Tønjum
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Neisseria Meningitidis ◽  
Quaternary Structure ◽  
Rotational Symmetry ◽  
Outer Membrane Proteins ◽  
Data Set ◽  
Type Iv ◽  
Transmission Electron ◽  
Total Data

ABSTRACT PilQ is a member of the secretin family of outer membrane proteins and is specifically involved in secretion of type IV pili inNeisseria meningitidis, Neisseria gonorrhoeae, andPseudomonas aeruginosa. The quaternary structure of PilQ from N. meningitidis was analyzed by transmission electron microscopy by using a negative stain. Single particle averaging was carried out with a total data set of 650 individual particles, which produced a projection map generated from 296 particles at an estimated resolution of 2.6 nm. Oligomeric PilQ adopts a donut-like structure with an external ring that is 16.5 nm in diameter surrounding a central cavity that is 6.5 nm in diameter. Self-rotation and power spectrum analysis demonstrated the presence of 12-fold rotational symmetry, showing that PilQ is organized as a ring of 12 identical subunits. A model of the type IV meningococcal pilus fiber, based on the X-ray crystal structure of the N. gonorrhoeae pilin subunit, fitted neatly into the cavity, demonstrating how PilQ could serve as a channel for the growing pilus fiber.

scholarly journals Testing the stability of the suitability coefficients from an eastern Bering Sea multispecies virtual population analysis

2005 ◽  
Vol 62 (5) ◽  
pp. 915-924 ◽  
Author(s):  
Jesús Jurado-Molina ◽  
Patricia A. Livingston ◽  
Vincent F. Gallucci
Keyword(s):  
Stomach Content ◽  
Bering Sea ◽  
Population Analysis ◽  
Data Set ◽  
Predator Species ◽  
Eastern Bering Sea ◽  
Virtual Population Analysis ◽  
Virtual Population ◽  
Total Data ◽  
The Stability

Abstract Suitability coefficients are important for the estimation of predation mortality in a multispecies virtual population analysis (MSVPA) and subsequent use in the multispecies forecasting model (MSFOR). Testing the assumption of the stability of the suitability coefficients is important in assessing the robustness of the predictions made with MSFOR. We used different statistical methods to partially test this assumption for the eastern Bering Sea MSVPA model with eight species, using stomach content data for the years 1985–1989. Comparison of the estimates from two different sets of stomach content data (set one with all data and set two mainly with data from 1985) suggested that the differences between the two types of estimates were much reduced when the number of predator stomachs sampled increased. In a second approach, we contrasted the residual variances of partial data sets with the results from the fit of the total data set. Results suggested a small increase (∼10.8%) in the variation of the suitability coefficients. Comparison of the means of the suitability coefficients associated with each predator species suggests that only 13 of the 50 possible pairwise contrasts were significantly different (α = 0.05). In general, results suggested that the predator preferences and prey vulnerabilities remained stable over the time period studied. Therefore, MSFOR could be considered as a tool to advise fisheries managers within a multispecies context.

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