Evaluation and sensitivity analysis of diatom DNA metabarcoding for WFD bioassessment of Mediterranean rivers

2020 ◽  
Vol 727 ◽  
pp. 138445 ◽  
Author(s):  
Javier Pérez-Burillo ◽  
Rosa Trobajo ◽  
Valentin Vasselon ◽  
Frédéric Rimet ◽  
Agnès Bouchez ◽  
...  
2021 ◽  
Vol 4 ◽  
Author(s):  
Rosa Trobajo ◽  
Javier Pérez Burillo ◽  
Valentin Vasselon ◽  
Frederic Rimet ◽  
Agnès Bouchez ◽  
...  

Recent metabarcoding work in European rivers, including our own studies of Mediterranean rivers in Catalonia (Pérez-Burillo et al. 2020), has shown promising agreement between morphology- (LM) and DNA-based (HTS) assessments of diatom periphyton for the Water Framework Directive. However, in 10 out of the 164 Catalan sites we analysed, the ecological status class was downgraded from “Good”/ “High” with LM to “Moderate”/ “Poor”/ “Bad”by HTS. We call these the “critical” sites and they are especially important because the WFD requires remedial action to be taken by water managers for any river stretch with Moderate or lower status. In order to discover the reasons for downgrading we investigated the contribution of each species to the Indice de Polluosensibilité Spécifique [Specific Pollution-sensitivity Index, IPS] using a “leave-one-out” sensitivity analysis, paying special attention to the critical sites. Discrepancies in IPS between LM and HTS were mainly due to the misidentification and overlooking in LM of a few species, which were better recovered by HTS. This bias was particularly important in the case of Fistulifera saprophila, whose clear underrepresentation in LM was important for explaining 8 out of the 10 critical sites and probably reflected destruction of its very weakly-silicified frustules during sample preparation for LM. Another important bias was brought about by differences between species in the rbcL copy number per cell, which for example affected the relative abundance obtained by HTS for Nitzschia inconspicua and Ulnaria ulna; these species were also identified by the sensitivity analysis as important for the WFD. However, blanket application of a correction factor based on cell volume did not lead to a clear improvement in the agreement between HTS and LM assessments. Only minor IPS discrepancies could be attributed to the incompleteness of the reference library, as most of the abundant and influential species (to the IPS) were well represented there. Finally, we propose that leave-one-out analysis is a valuable method for identifying priority species for isolation and barcoding that are currently not, or only poorly, represented in the DNA reference database.


Author(s):  
Empya Charlie ◽  
Siti Rusdiana ◽  
Rini Oktavia

Penelitian ini bertujuan untuk mengoptimalkan penjadwalan karyawan di CV. Karya Indah Bordir dalam melakukan tugas-tugas tertentu menggunakan metode Hungaria, serta menganalisis sensitivitas solusi optimal jika ada pengurangan waktu karyawan untuk menyelesaikan tugas-tugas. Metode Hongaria diterapkan pada proses bordir yang melibatkan 11 karyawan dan 10 tugas. Hasil penjadwalan yang optimal meminimalkan waktu produksi bordir perusahaan. Hasil penjadwalan optimal yang ditemukan adalah: karyawan 1 mengerjakan tas Mambo, karyawan 2 mengerjakan tas Elli, karyawan 3 mengerjakan tas Lonjong, karyawan 4 mengerjakan tas Tampang bunga, karyawan 6 mengerjakan tas Ransel, karyawan 7 mengerjakan tas Tima, karyawan 8 mengerjakan tas Keong, karyawan 9 mengerjakan tas Alexa, karyawan 10 mengerjakan tas Luna, dan karyawan 11 mengerjakan tas Mikha, dengan total waktu kerja adalah 13,7 jam. Setelah metode Hongaria diterapkan, CV. Karya Indah Bordir mendapat peningkatan pendapatan sebanyak 9,09%. Analisis sensitivitas dilakukan dengan mengurangi waktu karyawan dalam menyulam tas. Hasil analisis sensitivitas adalah beberapa batasan untuk variabel basis dan non basis untuk mempertahankan solusi optimal.   This research has a purpose to optimize the scheduling of employees in CV. Karya Indah Bordir in doing certain tasks using Hungarian method, as well as analyzing the sensitivity of the optimal solution if there is a reduction on the employees time to finish the tasks. The Hungarian method was applied on the embroidery process involving 11 employees and 10 tasks. The optimal scheduling result minimize the time of the embroidery production of the company. The optimal scheduling result found is: employee 1 does the Mambo bag, employee 2 does the Elli bag, employee 3 does the Lonjong bag, employee 4 does the Tampang bunga bag, employee 6 does the Ransel, employee 7 does the Tima bag, employee 8 does the Keong bag, employee 9 does the Alexa bag, employees 10 does the Luna bag, and employee 11 does the Mikha bag, with the total work time is 13,7 hours. After the Hungarian method was applied, CV. Karya Indah Bordir got the increasing revenue as much as 9,09 %. The sensitivity analysis was conducted by reducing the time of the employees take in embroidery the bags. The results of the sensitivity analysis are some boundaries for basis and non basis variables to maintain the optimal solution. 


2019 ◽  
Vol 2 (5) ◽  
Author(s):  
Mengda Zhang ◽  
Chenjing Zhou ◽  
Tian-tian Zhang ◽  
Yan Han

Selecting check index quantitatively is the core of the calibration of micro traffic simulation parameters at signal intersection. Five indexes in the node (intersection) module of VISSIM were selected as the check index set. Twelve simulation parameters in the core module were selected as the simulation parameters set. Optimal process of parameter calibration was proposed and model of the intersection of Huangcun west street and Xinghua street in Beijing was built in VISSIM to verify it. The sensitivity analysis between each check index and simulation parameter in their own set was conducted respectively. Sensitive parameter sets of different check indices were obtained and compared. The results show that different indexes have different size of set, and average vehicle delay's is maximum, so it's necessary to select index quantitatively. The results can provide references for scientific selection of the check indexes and improve the study efficiency of parameter calibration.


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