Physical and biological variability in the Namibian upwelling system: October 1997–October 2001

AbstractRecent technological advances, such as single-cell RNA sequencing (scRNA-seq), allow the measurement of gene expression profiles of individual cells. These expression profiles typically exhibit substantial variations even across seemingly homogeneous populations of cells. Two main different sources contribute to this measured variability: actual differences between the biological activity of the cells and technical measurement errors. Analysis of the biological variability may provide information about the underlying gene regulation of the cells, yet distinguishing it from the technical variability is a challenge. Here, we apply a recently developed computational method for measuring the global gene coordination level (GCL) to systematically study the cell-to-cell variability in numerical models of gene regulation. We simulate ‘biological variability’ by introducing heterogeneity in the underlying regulatory dynamic of different cells, while ‘technical variability’ is represented by stochastic measurement noise. We show that the GCL decreases for cohorts of cells with increased ‘biological variability’ only when it is originated from the interactions between the genes. Moreover, we find that the GCL can evaluate and compare—for cohorts with the same cell-to-cell variability—the ratio between the introduced biological and technical variability. Finally, we show that the GCL is robust against spurious correlations that originate from a small sample size or from the compositionality of the data. The presented methodology can be useful for future analysis of high-dimensional ecological and biochemical dynamics.

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Spanish society of laboratory medicine external quality assurance programmes: evolution of the analytical performance of clinical laboratories over 30 years and comparison with other programmes

Advances in Laboratory Medicine / Avances en Medicina de Laboratorio ◽

10.1515/almed-2020-0019 ◽

2020 ◽

Vol 1 (2) ◽

Author(s):

Carmen Perich ◽

Carmen Ricós ◽

Fernando Marqués ◽

Joana Minchinela ◽

Angel Salas ◽

...

Keyword(s):

Quality Assurance ◽

State Of The Art ◽

Laboratory Medicine ◽

Analytical Performance ◽

External Quality Assurance ◽

Biological Variability ◽

External Quality ◽

Spanish Society ◽

Clinical Laboratories ◽

Quality Specifications

AbstractThe purpose of this study is to understand the evolution of the analytical performance of the laboratories participating in the Spanish society of laboratory medicine (SEQCML) external quality assurance (EQA) programmes during its 30 years of operation and to compare it with the performance of other EQA programmes to establish whether the results are similar. The results obtained during this period are evaluated by applying the biological variability (BV) and state of the art-derived quality specifications. In addition, the results are compared with those obtained by other EQA programme organisations. It is noted that the laboratories participating in the EQA–SEQCML programmes have improved their performance over 30 years of experience and that the specifications derived from biological variation are achievable. It is difficult to compare EQA programmes, due to lack of accessibility and the differences in the design of these programmes (control materials, calculations used and analytical specifications established). The data from this study show that for some biological magnitudes the results obtained by the programmes are not yet harmonised, although efforts are being made to achieve this. Organisers of EQA programmes should also join the harmonisation effort by providing information on their results to enable comparison.

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Concurrent validity, inter-unit reliability and biological variability of a low-cost pocket radar for ball velocity measurement in soccer and tennis

Journal of Sports Sciences ◽

10.1080/02640414.2020.1868090 ◽

2020 ◽

pp. 1-8

Author(s):

Alejandro Hernández-Belmonte ◽

Alejandro Sánchez-Pay

Keyword(s):

Velocity Measurement ◽

Concurrent Validity ◽

Low Cost ◽

Biological Variability ◽

Ball Velocity

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On the robustness of an eastern boundary upwelling ecosystem exposed to multiple stressors

Scientific Reports ◽

10.1038/s41598-021-81549-1 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Ndague Diogoul ◽

Patrice Brehmer ◽

Hervé Demarcq ◽

Salaheddine El Ayoubi ◽

Abou Thiam ◽

...

Keyword(s):

Multiple Stressors ◽

Marine Ecosystem ◽

Trophic Levels ◽

Sea Surface ◽

Relative Index ◽

Upwelling System ◽

The North ◽

Latitudinal Shift ◽

Large Marine Ecosystem ◽

North And South

AbstractThe resistance of an east border upwelling system was investigated using relative index of marine pelagic biomass estimates under a changing environment spanning 20-years in the strongly exploited southern Canary Current Large marine Ecosystem (sCCLME). We divided the sCCLME in two parts (north and south of Cap Blanc), based on oceanographic regimes. We delineated two size-based groups (“plankton” and “pelagic fish”) corresponding to lower and higher trophic levels, respectively. Over the 20-year period, all spatial remote sensing environmental variables increased significantly, except in the area south of Cap Blanc where sea surface Chlorophyll-a concentrations declined and the upwelling favorable wind was stable. Relative index of marine pelagic abundance was higher in the south area compared to the north area of Cap Blanc. No significant latitudinal shift to the mass center was detected, regardless of trophic level. Relative pelagic abundance did not change, suggesting sCCLME pelagic organisms were able to adapt to changing environmental conditions. Despite strong annual variability and the presence of major stressors (overfishing, climate change), the marine pelagic ressources, mainly fish and plankton remained relatively stable over the two decades, advancing our understanding on the resistance of this east border upwelling system.

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