Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.


The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation

Search Page


My NCBI Filters

Results by year

Table representation of search results timeline featuring number of search results per year.

Year Number of Results
1960 1
1987 1
1988 1
1996 1
2005 1
2009 3
2011 1
2012 1
2013 2
2014 2
2015 1
2023 0

Text availability

Article attribute

Article type

Publication date

Search Results

14 results

Results by year

Filters applied: . Clear all
Page 1
Frequently asked questions about global modeling.
Letellier C, Aguirre LA, Freitas US. Letellier C, et al. Among authors: freitas us. Chaos. 2009 Jun;19(2):023103. doi: 10.1063/1.3125705. Chaos. 2009. PMID: 19566238
A soy-based phosphatidylserine/ phosphatidic acid complex (PAS) normalizes the stress reactivity of hypothalamus-pituitary-adrenal-axis in chronically stressed male subjects: a randomized, placebo-controlled study.
Hellhammer J, Vogt D, Franz N, Freitas U, Rutenberg D. Hellhammer J, et al. Among authors: freitas u. Lipids Health Dis. 2014 Jul 31;13:121. doi: 10.1186/1476-511X-13-121. Lipids Health Dis. 2014. PMID: 25081826 Free PMC article. Clinical Trial.
Electron correlations in semiconductor heterostructures.
de Freitas U, Studart N. de Freitas U, et al. Phys Rev B Condens Matter. 1987 Oct 15;36(12):6677-6680. doi: 10.1103/physrevb.36.6677. Phys Rev B Condens Matter. 1987. PMID: 9942385 No abstract available.
Working conditions for safe detection of nonlinearity and noise titration.
Roulin E, Freitas US, Letellier C. Roulin E, et al. Among authors: freitas us. Phys Rev E Stat Nonlin Soft Matter Phys. 2011 Apr;83(4 Pt 2):046225. doi: 10.1103/PhysRevE.83.046225. Epub 2011 Apr 29. Phys Rev E Stat Nonlin Soft Matter Phys. 2011. PMID: 21599288
14 results