Nonmetric Clustering and Association Analysis: Implications for the Evaluation of Multispecies Toxicity Tests and Field Monitoring

Author(s):  
GB Matthews ◽  
RA Matthews ◽  
WG Landis
2019 ◽  
Vol 7 (2A) ◽  
Author(s):  
João Victor Torres de Moraes ◽  
Ricardo Luiz Calazans Luna Filho ◽  
Williams Nascimento de Siqueira ◽  
Hianna Arely Milca Fagundes Silva ◽  
Dewson Rocha Pereira ◽  
...  

Ionizing radiation has been applied in several areas of knowledge, among them the study of the radiomodifier activity of natural substances. These substances can modify the cellular response to the damage induced by the radiation. Therefore, this work aimed to evaluate the radiomodifier action of Pityrocarpa moniliformis extract on Biomphalaria glabrata embryos exposed to 60Co gamma radiation. Initially, toxicity tests were performed on the extract against the B. glabrata embryos for the choice of concentration that did not cause death and embryonic malformation. Then, the antioxidant activity of the P. moniliformis extract with flavonoids and phenolic compounds was evaluated by means of the ABTS method. To evaluate the radiomodifier activity of the extract, embryos were selected in the blastula stage and irradiated with 7.5 Gy in a 60Co source (gammacell-Co60). Then, the embryos were exposed for 24 h to the extract of P. moniliformis at a concentration of 250 μg/mL. The results showed that the extract of P. moniliformis presents flavonoids and enzymatic inhibition by ABTS, which demonstrates the presence of antioxidant compounds. However, the tests of the radiomodifier activity did not present radioprotective effect for embryos exposed to ionizing radiation.


Author(s):  
Radovan Bačík ◽  
Mária Oleárová ◽  
Martin Rigelský

The development of the Internet and the current technologies have contributed to a significant progress in the consumer shopping process. Today, shopping decisions are more intuitive and much easier to make. E-shops, search engines, customer reviews and other similar tools reduce costs of searching for products or product information, thus boosting the habit of searching for information on the Internet - "Research Shopper Phenomenon" (Verhoef et al. 2007). According to Verhoef et al. (2015), this phenomenon leads to a phenomenon where consumers search for product information using one channel (Internet) and then make a purchase through another channel (brick-and-mortar shop). Heinrich and Thalmair (2013) refer to this effect as the "research online, purchase offline" or "ROPO" effect for short. This phenomenon can also be observed in reverse. Keywords: customer behavior, research online – purchase offline, association analysis


2013 ◽  
Vol 1 (1) ◽  
pp. 52 ◽  
Author(s):  
Melky R Pattiwael ◽  
Remy E. P Mangindaan ◽  
Rudi Prabowo ◽  
Inneke F. M Rumengan

Cyanide (CN) through leaching process in the gold processing could produce tailings that have negative impacts on the aquatic environment. To determine the acute and chronic effects of cyanide on aquatic organisms, toxicity tests have been conducted in the laboratory using Daphnia sp.This zooplankton organism is recommended by APHA as standard test animals. In this study the test concentrations refer to the Ministerial Decree No. 202 of 2004 and Government Regulation No. 82 of 2001. Cyanide was analyzed as free CN and WADS CN. The result of acute toxicity test using cyanide solution showed that Daphnia could survive a maximum concentration of 0.2 ppm. LC50 values for 24 and 72 hours were 0,59 mg/L and 0,10 mg/l, respectively. The LT50 was found at 42 hours. Daphnia sp. produced different numbers of offspring at different CN concentrations, and changed their reproduction pattern from parthenogenesis to sexual reproduction after exposure to a cyanide concentration of 0.1 ppm for 24 hours©  Sianida (CN) melalui proses leaching dalam proses pengolahan emas menghasilkan limbah yang dapat memberi dampak negatif bagi lingkungan perairan. Untuk mengetahui sampai seberapa jauh CN dapat memberi efek akut dan kronis terhadap biota air, telah dilakukan uji toksisitas di laboratorium dengan menggunakan Daphnia sp. Zooplankton ini direkomendasikan oleh APHA sebagai salah satu hewan uji standar. Dalam penelitian ini konsentrasi uji yang dipakai mengacu pada peraturan yang berlaku, yaitu Keputusan Menteri No. 202, Tahun 2004, dan Peraturan Pemerintah No. 82, Tahun 2001. Analisis sianida yang dihitung adalah nilai free CN dan WADS CN. Hasil penelitian uji toksisitas akut dengan menggunakan larutan sianida didapati Daphnia mampu bertahan hidup sampai pada konsentrasi 0,2 ppm dan nilai LC50 berada pada konsentarsi 0,1 ppm serta LT50 pada jam ke 42. Hasil uji efek kronis, Daphnia sp. menghasilkan jumlah anakan yang berbeda pada konsentrasi CN yang berlainan, dan mengalami perubahan pola reproduksi dari partenogenesis menjadi seksual setelah dipaparkan pada kosentrasi sianida 0,1 ppm selama 24 jam©


A comment on Zhao J, Yang Y, Huang H, Li D, Gu D, Lu X, et al. Association of ABO blood group and Covid19 susceptability. medRxiv [PREPRINT]. 2020; https://doi.org/10.1101/2020.03.11.20031096. Zeng X, Fan H, Lu D, Huang F, Meng X, Li Z, et al. Association between ABO blood group and clinical outcomes of Covid19. medRxiv[PREPRINT].2020; https://doi.org/10.1101/2020.04.15.20063107. Zietz M, Tatonetti N. Testing the association between blood type and COVID-19 infection, intubation, and death medRxiv [PREPRINT]. 2020; https://doi.org/10.1101/2020.04.08.20058073. Ellinghaus D, Degenhardt F, Bujanda L, al. e. The ABO blood group and a chromosome 3 gene cluster associate with SRAS-CoV2 respitarory failure in an Italy-Spain genome-wide association analysis. medRxiv. 2020; https://doi.org/10.1101/2020.05.31.20114991.


2014 ◽  
Vol 40 (1) ◽  
pp. 7 ◽  
Author(s):  
Mao-Ni CHAO ◽  
De-Rong HAO ◽  
Zhi-Tong YIN ◽  
Jin-Yu ZHANG ◽  
Hai-Na SONG ◽  
...  

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