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AmeriFlux is a network of research sites that measure carbon, water, and energy fluxes between ecosystems and the atmosphere using the eddy covariance technique to study a variety of Earth science questions. AmeriFlux's diversity of ecosystems, instruments, and data-processing routines create challenges for data standardization, quality assurance, and sharing across the network. To address these challenges, the AmeriFlux Management Project (AMP) designed and implemented the BASE data-processing pipeline. The pipeline begins with data uploaded by the site teams, followed by the AMP team's quality assurance and quality control (QA/QC), ingestion of site metadata, and publication of the BASE data product. The semi-automated pipeline enables us to keep pace with the rapid growth of the network. As of 2022, the AmeriFlux BASE data product contains 3,130 site years of data from 444 sites, with standardized units and variable names of more than 60 common variables, representing the largest long-term data repository for flux-met data in the world. The standardized, quality-ensured data product facilitates multisite comparisons, model evaluations, and data syntheses.

Ovaries obtained from rats of 4 and 18 mo of age were incubated with H-pregnenolone as the added precursor. Incorporation of radioactivity into progesterone (p), 20α-dihydroprogesterone (20α-P), 17α-hydroxyprogesterone (17α-OHP), androstenedione, and testosterone were studied by serial paper and thin-layer chromatography. Significantly more P, 17α-OHP and androgen was produced by the older ovaries. Addition of hCG (100 I.U.) to the incubate increased 20α-P production in the ovaries of both age groups, depressed 17α-OHP and androgen formation in the ovaries of older rats, and had no effect on progesterone synthesis in either age group. Serum progesterone in 4-mo-old rats was 13.5 ± 1.91 ng/ml at estrus and 3.69 ± 0.9 ng/ml at diestrus, whereas serum progesterone in 18-mo-old rats was 0.85 ± 0.15 ng/ml at constant estrus and 1.23 ± 0.54 ng/ml at constant diestrus. Treatment with hCG for 20 days increased serum progesterone to 29.6 ng/ml in young rats and to 4.21 ± 2.0 ng/ml in older rats. Shorter treatments were less effective. These data reveal a definite change in steroidogenic competence in older rat ovaries. [ABSTRACT FROM PUBLISHER]

In reptiles, there is adequate evidence to indicate environmental control of the ovarian cycle through hvpothalamic pathways and the subsequent release of tropic hormone (s) from the anterior pituitary. The role of the pineal-parietal complex still remains to be elucidated. In the hypothalamus there appear to be steroid sensitive areas and both progesterone and estrogen appear to have important feedback influences upon gonadal growth ovulation, and ovarian steroid production. Cytological studies of the reptilian pituitary indicate similar cell types to those observed in mammalian pituitaries, but thus far, two gonadotrophs cannot be identified with any certainty. Chemical and biological studies of the action of mammalian gonadotropuis suggest that in reptiles hormones which are FSH-like in mammals are able to stimulate gonadal development, ovulation, and steroid biosynthesis under certain conditions. Preliminary studies of the chemistry of turtle gonadotropuis have so far demonstrated only one active principle, which is chemically similar to mammalian LH, but is far more active than the latter hormone in reptilian systems. Further, the hormone also has FSH-like activity in the reptile. Thus reptilian gonadal development can be stimulated by treatment with a variety of mammalian gonadotropins. Recent studies have indicited an important role for growth hormone, acting in concert with gonadotropin and estrogen in the regulation of vitellogenesis and ovarian growth. Piolactin appears to be an antigonadal agent in reptiles, as does progesterone. The exact manner in which these hormones exert their antigonadal action remains to be clarified, but at least one site of action is the central nervous system; other sites maybe the liver and the fat depot. Ovarian tissue from reptiles is able to synthesize and secrete steioid hormones by pathways similar to those present in mammalian ovaries. Circulating levels of estrogen have not been measured, but progesterone levels in the blood show distinct changes assocnted with pregnancy and the presence of corpora lutea in the ovary. [ABSTRACT FROM PUBLISHER]