scholarly journals Robust Measurement Selection Design for Experimental Systems with Input Uncertainty

2021 ◽  
Author(s):  
Ke Wang ◽  
Hong Yue
Keyword(s):  
Input Uncertainty ◽  
Experimental Systems ◽  
Measurement Selection

Wastewater Treatment by Stabilization Ponds with and without Macrophytes under Arid Climate

1993 ◽  
Vol 28 (10) ◽  
pp. 177-181 ◽  
Author(s):  
L. Mandi ◽  
N. Ouazzani ◽  
K. Bouhoum ◽  
A. Boussaid
Keyword(s):  
Bacterial Load ◽  
Fecal Coliforms ◽  
Arid Climate ◽  
Organic Load ◽  
Experimental Systems ◽  
Helminth Eggs ◽  
Stabilization Ponds ◽  
Treated Effluents ◽  
Summer Time ◽  
Influent Flow

This paper presents a comparative study of two experimental systems, stabilization ponds without macrophytes and macrophytic ponds, to purify wastewater under arid climate of Marrakesh. Organic load (COD, TSS), bacterial load (SF, CF) and parasitical load (helminth eggs) are significantly reduced in both systems. Even though water loss was more important at the macrophytic ponds (evapotranspiration reaches 60% of influent flow), this system shows generally the best efficiency in purifying wastewater. In summer time, TSS and COD depletion is better on macrophytic ponds (TSS: 95%, COD: 87%). The stabilization ponds are more efficient to reduce nutrients: NH4+: 72%. PO4: 63% at the same period. Fecal streptococci and fecal coliforms are reduced more in stabilization ponds (CF: 99.4%, SF: 99.7%) than macrophytic ponds (CF: 96.2%, SF: 94.7%). No helminth eggs were found in the effluent from either system. The two systems ensure optimal removal of parasites allowing the eventual reuse of the treated effluents for agricultural purposes.

scholarly journals A 3D Bioprinted Material That Recapitulates the Perivascular Bone Marrow Structure for Sustained Hematopoietic and Cancer Models

Polymers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 480
Author(s):  
Caitlyn A. Moore ◽  
Zain Siddiqui ◽  
Griffin J. Carney ◽  
Yahaira Naaldijk ◽  
Khadidiatou Guiro ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Bone Marrow ◽  
Translational Medicine ◽  
Drug Response ◽  
Drug Approval ◽  
3D Models ◽  
3D Bioprinting ◽  
Effective Evaluation ◽  
Experimental Systems ◽  
Cancer Models

Translational medicine requires facile experimental systems to replicate the dynamic biological systems of diseases. Drug approval continues to lag, partly due to incongruencies in the research pipeline that traditionally involve 2D models, which could be improved with 3D models. The bone marrow (BM) poses challenges to harvest as an intact organ, making it difficult to study disease processes such as breast cancer (BC) survival in BM, and to effective evaluation of drug response in BM. Furthermore, it is a challenge to develop 3D BM structures due to its weak physical properties, and complex hierarchical structure and cellular landscape. To address this, we leveraged 3D bioprinting to create a BM structure with varied methylcellulose (M): alginate (A) ratios. We selected hydrogels containing 4% (w/v) M and 2% (w/v) A, which recapitulates rheological and ultrastructural features of the BM while maintaining stability in culture. This hydrogel sustained the culture of two key primary BM microenvironmental cells found at the perivascular region, mesenchymal stem cells and endothelial cells. More importantly, the scaffold showed evidence of cell autonomous dedifferentiation of BC cells to cancer stem cell properties. This scaffold could be the platform to create BM models for various diseases and also for drug screening.

scholarly journals Mechatronics: Experiential Learning and the Stimulation of Thinking Skills

2021 ◽  
Vol 11 (2) ◽  
pp. 46
Author(s):  
Maki K. Habib ◽  
Fusaomi Nagata ◽  
Keigo Watanabe
Keyword(s):  
Critical Thinking ◽  
Experiential Learning ◽  
Learning Process ◽  
Laboratory Experiments ◽  
Thinking Skills ◽  
Project Based Learning ◽  
Critical Thinking Skills ◽  
Learning Approach ◽  
Learning Approaches ◽  
Experimental Systems

The development of experiential learning methodologies is gaining attention, due to its contributions to enhancing education quality. It focuses on developing competencies, and build-up added values, such as creative and critical thinking skills, with the aim of improving the quality of learning. The interdisciplinary mechatronics field accommodates a coherent interactive concurrent design process that facilitates innovation and develops the desired skills by adopting experiential learning approaches. This educational learning process is motivated by implementation, assessment, and reflections. This requires synergizing cognition, perception, and behavior with experience sharing and evaluation. Furthermore, it is supported by knowledge accumulation. The learning process with active student’s engagement (participation and investigation) is integrated with experimental systems that are developed to facilitate experiential learning supported by properly designed lectures, laboratory experiments, and integrated with course projects. This paper aims to enhance education, learning quality, and contribute to the learning process, while stimulating creative and critical thinking skills. The paper has adopted a student-centered learning approach and focuses on developing training tools to improve the hands-on experience and integrate it with project-based learning. The developed experimental systems have their learning indicators where students acquire knowledge and learn the target skills through involvement in the process. This is inspired by collaborative knowledge sharing, brainstorming, and interactive discussions. The learning outcomes from lectures and laboratory experiments are synergized with the project-based learning approach to yield the desired promising results and exhibit the value of learning. The effectiveness of the developed experimental systems along with the adopted project-based learning approach is demonstrated and evaluated during laboratory sessions supporting different courses at Sanyo-Onoda City University, Yamaguchi, Japan, and at the American University in Cairo.

scholarly journals Standardized Method for the Assessment of Behavioral Responses of Zebrafish Larvae

Biomedicines ◽  
2021 ◽  
Vol 9 (8) ◽  
pp. 884
Author(s):  
Hideyuki Maeda ◽  
Noritoshi Fukushima ◽  
Akihiro Hasumi
Keyword(s):  
Early Stage ◽  
Scientific Evidence ◽  
Video Tracking ◽  
Abnormal Behavior ◽  
Laboratory Setting ◽  
Zebrafish Larvae ◽  
Experimental Systems ◽  
Standardized Method ◽  
Life Phenomena ◽  
And Behavior

Zebrafish are easy to breed in a laboratory setting as they are extremely fertile and produce dozens of eggs per set. Because zebrafish eggs and the skin of the early-stage larvae are transparent, their embryos and the hearts and muscles of their larvae can be easily observed. Multiple rapid analyses of heart rate and behavior can be performed on these larvae simultaneously, enabling investigation of the influence of neuroactive substances on abnormal behavior, death, and associated pathogenetic mechanisms. Zebrafish larvae are becoming increasingly popular among researchers and are used in laboratories worldwide to study various vertebrate life phenomena; more experimental systems using zebrafish will undoubtedly be developed in the future. However, based on the available literature, we believe that the conceptualization of a protocol based on scientific evidence is necessary to achieve standardization. We exposed zebrafish larvae at 6–7 days post-fertilization to 50 repeated light–dark stimuli at either 15-min or 5-min intervals. We measured the traveled distance and habituation time through a video tracking apparatus. The traveled distance stabilized after the 16th repetition when the zebrafish were exposed to light–dark stimuli at 15-min intervals and after the 5th repetition when exposed at 5-min intervals. Additionally, at 15-min intervals, the peak of the traveled distance was reached within the first minute in a dark environment, whereas at 5-min intervals, it did not reach the peak even after 5 min. The traveled distance was more stable at 5-min intervals of light/dark stimuli than at 15-min intervals. Therefore, if one acclimatizes zebrafish larvae for 1 h and collects data from the 5th repetition of light/dark stimuli at intervals of 5 min in the light/dark test, a stable traveled distance result can be obtained. The establishment of this standardized method would be beneficial for investigating substances of unknown lethal concentration.

scholarly journals Generalizing game-changing species across microbial communities

2021 ◽  
Vol 1 (1) ◽  
Author(s):  
Jie Deng ◽  
Marco Tulio Angulo ◽  
Serguei Saavedra
Keyword(s):  
Microbial Communities ◽  
Context Dependency ◽  
Heuristic Rules ◽  
Resident Species ◽  
Experimental Systems ◽  
Environment And Health ◽  
Structuralist Theory ◽  
Context Specific

AbstractMicrobes form multispecies communities that play essential roles in our environment and health. Not surprisingly, there is an increasing need for understanding if certain invader species will modify a given microbial community, producing either a desired or undesired change in the observed collection of resident species. However, the complex interactions that species can establish between each other and the diverse external factors underlying their dynamics have made constructing such understanding context-specific. Here we integrate tractable theoretical systems with tractable experimental systems to find general conditions under which non-resident species can change the collection of resident communities—game-changing species. We show that non-resident colonizers are more likely to be game-changers than transients, whereas game-changers are more likely to suppress than to promote resident species. Importantly, we find general heuristic rules for game-changers under controlled environments by integrating mutual invasibility theory with in vitro experimental systems, and general heuristic rules under changing environments by integrating structuralist theory with in vivo experimental systems. Despite the strong context-dependency of microbial communities, our work shows that under an appropriate integration of tractable theoretical and experimental systems, it is possible to unveil regularities that can then be potentially extended to understand the behavior of complex natural communities.

scholarly journals Natural Variation in Plant Pluripotency and Regeneration

Plants ◽  
2020 ◽  
Vol 9 (10) ◽  
pp. 1261
Author(s):  
Robin Lardon ◽  
Danny Geelen
Keyword(s):  
De Novo ◽  
Shoot Organogenesis ◽  
In Vitro Regeneration ◽  
Relative Role ◽  
Root Explants ◽  
Experimental Systems ◽  
Complex Process ◽  
Insight Into ◽  
Molecular Framework

Plant regeneration is essential for survival upon wounding and is, hence, considered to be a strong natural selective trait. The capacity of plant tissues to regenerate in vitro, however, varies substantially between and within species and depends on the applied incubation conditions. Insight into the genetic factors underlying this variation may help to improve numerous biotechnological applications that exploit in vitro regeneration. Here, we review the state of the art on the molecular framework of de novo shoot organogenesis from root explants in Arabidopsis, which is a complex process controlled by multiple quantitative trait loci of various effect sizes. Two types of factors are distinguished that contribute to natural regenerative variation: master regulators that are conserved in all experimental systems (e.g., WUSCHEL and related homeobox genes) and conditional regulators whose relative role depends on the explant and the incubation settings. We further elaborate on epigenetic variation and protocol variables that likely contribute to differential explant responsivity within species and conclude that in vitro shoot organogenesis occurs at the intersection between (epi) genetics, endogenous hormone levels, and environmental influences.

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