Low cross-taxon congruence among aquatic organisms in artificial tropical ponds: implications for biomonitoring

Author(s):  
Fernanda Melo Carneiro ◽  
João Paulo Francisco de Souza ◽  
Karina Dias Silva ◽  
Denis Silva Nogueira ◽  
David Bichsel ◽  
...  

The use of biodiversity surrogates is often suggested to increase the cost-effectiveness of biomonitoring programs, as this demands less time and taxonomic expertise. In addition, the detection of multi-taxon associations is a first step toward a better understanding of how organisms interact with each other. Such a multi-taxon association is termed a congruence, and can be detected through measuring the similarity in the distributional patterns shown by different biological groups. To assess the ability of different taxa to serve as surrogates for others, we carried out a Procrustes analysis on the beta diversity patterns of seven biological groups (aquatic birds, Amphibians, Macrophytes, Coleoptera, Odonata, Heteroptera and phytoplankton) in 35 ponds of the Cerrado biome. We found that: (i) the values of congruence in the studied ponds were weak; (ii) among all the biological groups compared, the highest congruence was found between amphibians and macrophytes; (iii) amphibians were congruent with the Coleoptera, Heteroptera, and macrophytes; (iv) the different taxa studied had different responses to environmental conditions; and (v) although they showed relatively weak congruence with the other taxa in each pond environment, amphibian communities were the most strongly influenced by environment variables. Almost all the communities observed in these systems showed unique pattern and thus should be studied and monitored in their entirety.

2012 ◽  
Vol 102 (7) ◽  
pp. 3561-3573 ◽  
Author(s):  
Ayala Arad ◽  
Ariel Rubinstein

We study experimentally a new two-player game: each player requests an amount between 11 and 20 shekels. He receives the requested amount and if he requests exactly one shekel less than the other player, he receives an additional 20 shekels. Level-k reasoning is appealing due to the natural starting point (requesting 20) and the straightforward best-response operation. Nevertheless, almost all subjects exhibit at most three levels of reasoning. Two variants of the game demonstrate that the depth of reasoning is not increased by enhancing the attractiveness of the level-0 strategy or by reducing the cost of undercutting the other player.


Vox Patrum ◽  
2011 ◽  
Vol 56 ◽  
pp. 339-348
Author(s):  
Bogdan Czyżewski

Although St. Basil did not live 50 years, the topic of the old age appears in his works quite often. On the other hand, it is clear that Basil does not discuss this issue in one par­ticular work or in the longer argumentation. The fragmentary statements about old age can be found in almost all his works, but most of them can be found in the correspondence of Basil. In this paper we present the most important ad the most interesting aspect of teach­ing of Basil the Great. As these certificates show that the bishop of Caesarea looked at the old age maturely, rationally estimated passage of time, which very often makes a man different. He experienced it, for example as a spiritual and physical suffering, which often were connected with his person. He saw a lot of aspect of the old age, especially its advan­tages – spiritual maturity and wisdom. What is more, he pointed also to passage of time, which leads a man to eternity, which should be prepared to, regardless how old he is. In his opinion fear is not seen opinions of St. Basil present really Christian way of thinking, well-balanced and calm.


2020 ◽  
Vol 12 (7) ◽  
pp. 2767 ◽  
Author(s):  
Víctor Yepes ◽  
José V. Martí ◽  
José García

The optimization of the cost and CO 2 emissions in earth-retaining walls is of relevance, since these structures are often used in civil engineering. The optimization of costs is essential for the competitiveness of the construction company, and the optimization of emissions is relevant in the environmental impact of construction. To address the optimization, black hole metaheuristics were used, along with a discretization mechanism based on min–max normalization. The stability of the algorithm was evaluated with respect to the solutions obtained; the steel and concrete values obtained in both optimizations were analyzed. Additionally, the geometric variables of the structure were compared. Finally, the results obtained were compared with another algorithm that solved the problem. The results show that there is a trade-off between the use of steel and concrete. The solutions that minimize CO 2 emissions prefer the use of concrete instead of those that optimize the cost. On the other hand, when comparing the geometric variables, it is seen that most remain similar in both optimizations except for the distance between buttresses. When comparing with another algorithm, the results show a good performance in optimization using the black hole algorithm.


2016 ◽  
Vol 18 (1) ◽  
Author(s):  
Roelof Baard ◽  
George Nel

Background: Although research shows that almost all listed companies have corporate websites with dedicated investor relations (IR) sections that enable companies to ‘push’ information to investors, it was argued that such an asymmetrical approach to communication is insufficient for companies wishing to exercise good IR. The purpose of this study was to test the effectiveness of the Internet to act as a mechanism to achieve more interactive communication between companies and investors.Objectives: The objectives of the study were to measure the responsiveness, timeliness and relevance of companies’ responses to e-mail requests, and to test for the determinants (size, market-to-book ratio, profitability, leverage and liquidity) thereof.Method: The mystery investor approach and a content analysis were used to study the e-mail handling performance of companies. The associations between company-specific characteristics were statistically tested.Results: It was found that the e-mail handling performance of companies in this study was poor compared with previous studies. Significant relationships between company size and responsiveness and relevance, and between market-to-book ratio and relevance were reported, as well as between the contact method used to request information and relevance and the use of social media and timeliness.Conclusion: Specific areas where companies could improve their investor communications were identified. The need for further research was discussed to explain some of the relationships found, as well as those not found, in contrast to what was expected. Future research is warranted to examine the relationship between the e-mail handling performance of companies and information asymmetry and the cost of equity of companies.


2020 ◽  
Vol 3 (1) ◽  
pp. 61
Author(s):  
Kazuhiro Aruga

In this study, two operational methodologies to extract thinned woods were investigated in the Nasunogahara area, Tochigi Prefecture, Japan. Methodology one included manual extraction and light truck transportation. Methodology two included mini-forwarder forwarding and four-ton truck transportation. Furthermore, a newly introduced chipper was investigated. As a result, costs of manual extractions within 10 m and 20 m were JPY942/m3 and JPY1040/m3, respectively. On the other hand, the forwarding cost of the mini-forwarder was JPY499/m3, which was significantly lower than the cost of manual extractions. Transportation costs with light trucks and four-ton trucks were JPY7224/m3 and JPY1298/m3, respectively, with 28 km transportation distances. Chipping operation costs were JPY1036/m3 and JPY1160/m3 with three and two persons, respectively. Finally, the total costs of methodologies one and two from extraction within 20 m to chipping were estimated as JPY9300/m3 and JPY2833/m3, respectively, with 28 km transportation distances and three-person chipping operations (EUR1 = JPY126, as of 12 August 2020).


Games ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 53
Author(s):  
Roberto Rozzi

We consider an evolutionary model of social coordination in a 2 × 2 game where two groups of players prefer to coordinate on different actions. Players can pay a cost to learn their opponent’s group: if they pay it, they can condition their actions concerning the groups. We assess the stability of outcomes in the long run using stochastic stability analysis. We find that three elements matter for the equilibrium selection: the group size, the strength of preferences, and the information’s cost. If the cost is too high, players never learn the group of their opponents in the long run. If one group is stronger in preferences for its favorite action than the other, or its size is sufficiently large compared to the other group, every player plays that group’s favorite action. If both groups are strong enough in preferences, or if none of the groups’ sizes is large enough, players play their favorite actions and miscoordinate in inter-group interactions. Lower levels of the cost favor coordination. Indeed, when the cost is low, in inside-group interactions, players always coordinate on their favorite action, while in inter-group interactions, they coordinate on the favorite action of the group that is stronger in preferences or large enough.


1978 ◽  
Vol 56 (9) ◽  
pp. 2055-2057 ◽  
Author(s):  
J. W. Moore ◽  
I. A. Moore

Descriptions of larvae of Procladius denticulatus, Procladius culiciformis, Procladius freemani, and Procladius bellus collected from Yellowknife Bay (lat., 62°25′; long., 114°20′) are given. Procladius denticulatus was separated from the other species by its large size, a character which always proved distinctive. Procladius culiciformis and P. freemani were separated from one another through several measurements including those of the basal antennal segment and the basal palpal segment. Almost all characters of the head were useful in distinguishing the much smaller P. bellus from the other species.


2014 ◽  
Vol 665 ◽  
pp. 643-646
Author(s):  
Ying Liu ◽  
Yan Ye ◽  
Chun Guang Li

Metalearning algorithm learns the base learning algorithm, targeted for improving the performance of the learning system. The incremental delta-bar-delta (IDBD) algorithm is such a metalearning algorithm. On the other hand, sparse algorithms are gaining popularity due to their good performance and wide applications. In this paper, we propose a sparse IDBD algorithm by taking the sparsity of the systems into account. Thenorm penalty is contained in the cost function of the standard IDBD, which is equivalent to adding a zero attractor in the iterations, thus can speed up convergence if the system of interest is indeed sparse. Simulations demonstrate that the proposed algorithm is superior to the competing algorithms in sparse system identification.


2010 ◽  
Vol 26 (2) ◽  
pp. 170-174 ◽  
Author(s):  
Shin Yuh Ang ◽  
Rachel Woo Yin Tan ◽  
Mariko Siyue Koh ◽  
Jeremy Lim

Objectives: Endobronchial ultrasound (EBUS), encompassing endobronchial ultrasound transbronchial needle aspiration (EBUS-TBNA) and Endobronchial ultrasound transbronchial lung biopsy (EBUS-TBLB) has been proven to be a useful modality in the staging and diagnosis of lung cancer. However, there are limited publications on the cost-effectiveness of EBUS and no economic evaluations relevant to the Singapore setting. An economic evaluation using our hospital's data was used to assess the cost implications of EBUS substituting where clinically appropriate: transthoracic needle aspiration; (TTNA), fluoroscopy-guided transbronchial lung biopsy (TBLB), and mediastinoscopy in the diagnosis and staging of lung cancer.Methods: Relationship between the clinical and economic implications of alternative modalities was modeled using data inputs that were relevant to the Singapore setting. Two decision analytic models were constructed to evaluate the cost of EBUS compared with TTNA, TBLB, and staging mediastinoscopy. Only direct costs were imputed.Results: In the base–case analysis, TTNA was the most economical strategy (SGD3,335 = US$2,403) where clinically suitable for the diagnosis of lung cancer as compared to the other options: TBLB (SGD4,499) and EBUS-TBLB (SGD4,857). On the other hand, EBUS-TBNA resulted in expected cost savings of SGD1,214 per positive staging of lung cancer as compared to mediastinoscopy.Conclusions: The use of EBUS-TBNA could result in cost savings of SGD1,214 per positive staging of lung cancer as compared to mediastinoscopy. Whereas TTNA was the most economical intervention for the diagnosis of lung cancer as compared to the other options, its main limitation lies in its suitability only for peripheral lung lesions and high complication rate.


1981 ◽  
Vol 8 (1) ◽  
pp. 203 ◽  
Author(s):  
AA Burbidge

Western swamp tortoise (Pseudemydura umbrina) was rediscovered in Western Australia in 1954. It is a relict species of a monotypic genus, of very restricted range and specialized habitat. Population was estimated to be 13 to 45 and decreasing at 1 of its 2 native reserves and to be 10 to 45 and static at the other reserve. It does not use permanent water, but lives and feeds in ephemeral winter swamps and spends the other 6 to 9 months of the year in refuges in leaf litter, under fallen branches or in holes in the ground, in contact with the soil. The tortoise is carnivorous and in the wild takes only live aquatic organisms. Captive adults will not take meat until they have starved for many months. Stomach of 1 female (Edward, pers. commun.) had aquatic crustaceans, chiefly Eulimnadia sp., with insects and insect larvae, mainly Coleoptera and Diptera. Study of faeces confirmed that observation had shown that small tadpoles and an aquatic earthworm (Eodrilus cornigravei) were eaten also. Reproduction, growth, activity relative to body and water temperature, and desiccation rate, were noted. One adult female tortoise was eaten by a fox. Foxes and bandicoots (Isoodon obesulus) eat eggs of other tortoises and would eat those of P. umbrina. Hatchlings may be eaten by large wading birds such as straw-necked ibis (Threskiornis spinicollis) and white-faced heron (Notophoyx novaehollandiae).


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