The Primary STEM Ideas Book

The primary stem cells of the cerebral cortex are the radial glial cells (RGCs), and disturbances in their operation lead to myriad brain disorders in all mammals from mice to humans. Here, we found in mice that maternal gestational obesity and hyperglycemia can impair the maturation of RGC fibers and delay cortical neurogenesis. To investigate potential mechanisms, we used optogenetic live-imaging approaches in embryonic cortical slices. We found that Ca2+signaling regulates mitochondrial transport and is crucial for metabolic support in RGC fibers. Cyclic intracellular Ca2+discharge from localized RGC fiber segments detains passing mitochondria and ensures their proper distribution and enrichment at specific sites such as endfeet. Impairment of mitochondrial function caused an acute loss of Ca2+signaling, while hyperglycemia decreased Ca2+activity and impaired mitochondrial transport, leading to degradation of the RGC scaffold. Our findings uncover a physiological mechanism indicating pathways by which gestational metabolic disturbances can interfere with brain development.

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Chloroquine or Chloroquine-PI3K/Akt Pathway Inhibitor Combinations Strongly Promote γ-Irradiation-Induced Cell Death in Primary Stem-Like Glioma Cells

PLoS ONE ◽

10.1371/journal.pone.0047357 ◽

2012 ◽

Vol 7 (10) ◽

pp. e47357 ◽

Cited By ~ 63

Author(s):

Elke Firat ◽

Astrid Weyerbrock ◽

Simone Gaedicke ◽

Anca-Ligia Grosu ◽

Gabriele Niedermann

Keyword(s):

Cell Death ◽

Glioma Cells ◽

Akt Pathway ◽

Γ Irradiation ◽

Primary Stem

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THE DEVELOPMENT OF A CURIOSITY TOWARDS PRIMARY STEM EDUCATION QUESTIONNAIRE INSTRUMENT

International Journal of Education, Psychology and Counseling ◽

10.35631/ijepc.640023 ◽

2021 ◽

Vol 6 (40) ◽

pp. 274-292

Author(s):

Jamilah Ahmad ◽

Nyet Moi Siew

Keyword(s):

Stem Education ◽

Primary Schools ◽

High Reliability ◽

Measurement Model ◽

Validity And Reliability ◽

School Students ◽

Item Fit ◽

Primary Stem ◽

Item Reliability ◽

Variance Explained

The Curiosity towards STEM Education Questionnaire Instrument (CQI-STEM) was developed to measure the level of curiosity towards STEM education among primary school students. CQI-STEM consisted of 10 items measuring the two constructs of curiosity towards STEM, namely stretching, and embracing. A total of 166 years five students aged 10 to 11 years enrolled in five urban schools in the Tawau district, Sabah was involved as a research sample. Rasch Measurement Model was applied to determine the validity and reliability of CQI-STEM. The results of the validity analysis found that the polarity of the items through the PTMEA-CORR values showed that all 10 items were > .00 (+). Through item fit analysis, all items were retained because items meet the requirements of the range in MNSQ outfit, ZSTD outfit, and PTMEA-CORR. The value of Raw Variance Explained by Measures was 63.1% (excellent) and the value of Unexplained variance in the first contrast was below 15%, showing that the instrument had strong dimensionality and high construct validity. The CQI-STEM instrument was found to have high reliability with a Cronbach’s alpha value (KR-20) of .93. Results also showed that CQI-STEM has excellent item reliability and moderate-high item separation value of .96 and 4.83 respectively. CQI-STEM also has high person reliability and person separation value of .92 and 3.48 respectively. In conclusion, CQI-STEM has good validity and high reliability in measuring curiosity towards STEM Education among year five students in primary schools.

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Sent to the Corner: xylem vessel anatomy not surface area determines megaphyll hydraulics in Cecropia obtusa Trécul (Urticaceae)

10.1101/259036 ◽

2018 ◽

Cited By ~ 1

Author(s):

Sébastien Levionnois ◽

Sabrina Coste ◽

Eric Nicolini ◽

Clément Stahl ◽

Hélène Morel ◽

...

Keyword(s):

Cross Sections ◽

Specific Conductivity ◽

Secondary Growth ◽

Cross Sectional ◽

Positive Correlation ◽

Leaf Level ◽

Leaf Dimensions ◽

Level Model ◽

Primary Stem ◽

Leaf Model

AbstractCorners rule predicts a positive correlation between leaf dimensions and the cross-sectional area of the primary stem. Although this relationship is usually explained by hydraulic and mechanical requirements, these hypotheses have never been tested empirically. However, Corner’s rule is tricky to investigate since rapid secondary growth of the stem prevents a rigorous link being established between a given leaf and the supporting stem. We chose a twig-like leaf model since petiole anatomy is only linked to the attached lamina. We tested the hypothesis that anatomical adjustments to hydraulic requirements related to vessel size enable reduced investment in tissue in the framework of Corner’s rule. We conducted a functional, mechanistic and intraspecific investigation of Cecropia obtusa Trécul, a Neotropical pioneer tree, by integrating morphological, anatomical and theoretical hydraulic traits around the lamina-petiole size relationship. The twig-like structure of the leaf and the strong lamina-petiole correlation of this model tree species made it possible to use the leaf-level model for a rigorous investigation of the functional implications of Corner’s rule. We found a positive correlation between petiole size, lamina size, the ratio of mean vessel area to vessel frequency in the petiole xylem and theoretical specific conductivity in the petiole xylem. Hydraulic function supports Corner’s rule to a lesser extent than previously thought. Variations in vessel dimensions mainly drive xylem hydraulic performances and avoid disproportionate petiole cross-sections to answer to hydraulic requirements associated with lamina size.

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Faculty Opinions recommendation of Chloroquine or chloroquine-PI3K/Akt pathway inhibitor combinations strongly promote γ-irradiation-induced cell death in primary stem-like glioma cells.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.717968148.793467955 ◽

2012 ◽

Author(s):

John Lazo

Keyword(s):

Cell Death ◽

Glioma Cells ◽

Akt Pathway ◽

Γ Irradiation ◽

Primary Stem

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THE CONTROL OF GROWTH AND DEVELOPMENT IN RED CLOVER (TRIFOLIUM PRATENSE L.): I. RECORDING AND ANALYSIS OF DEVELOPMENTAL PATTERNS IN MORPHOGENESIS

Canadian Journal of Plant Science ◽

10.4141/cjps59-002 ◽

1959 ◽

Vol 39 (1) ◽

pp. 9-24 ◽

Cited By ~ 7

Author(s):

Bruce G. Cumming

Keyword(s):

Shoot Growth ◽

Indoleacetic Acid ◽

Trifolium Pratense ◽

Red Clover ◽

Simple Method ◽

Node Number ◽

Developmental Patterns ◽

Lateral Bud ◽

Trifolium Pratense L ◽

Primary Stem

A key is described that provides a simple method for recording the sequential distribution of all leaves, buds, and inflorescences visible on a primary stem. Numbers are assigned to nodes in a basipetal sequence with each flowering node as number 1.In the "first cycle of growth" of a primary bud the number of nodes on each lateral flowering shoot was found to be positively correlated with, and linearly related to, the number of the node at which each was borne. It was also found that both the number of buds, non-flowering and flowering shoots, [T], and the number of inflorescences, [I], were linearly related to primary node number. Indoleacetic acid (IAA), 2,3,5-triiodobenzoic acid (TIBA), and maleic hydrazide amine (MH), altered the amount of lateral bud and shoot growth but not the linear relationships.Attainment of "ripeness-to-flower" coincident with production of a systemic non-polar florigenic stimulus could result in the observed conformity to theoretically "expected node numbers for flowering" on all lateral shoots.Treatment with 800 p.p.m. MH caused abortion of inflorescences and hastened onset of the "second cycle of vegetative growth" through cessation of growth and differentiation of "first cycle" floral apices; virus infection has caused similar effects.

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