Search results for "figuration"
showing 10 items of 615 documents
Experimental and numerical analysis on FSWed magnesium alloy thin sheets obtained using “pin” and “pinless” tool
2012
Acid rearrangment of epoxy-germacranolides and absolute configuration of 1beta, 10alpha-epoxy-salonitenolide
2010
The acid-catalyzed cyclization of mono epoxides of cnicin acetonide (3) was investigated. Several 6,12-eudesmanolides were obtained, and their stereochemistry established by extensive spectroscopic analyses. Chemical correlations also led to the assignment of the absolute configuration of 1beta,10alpha-epoxy-salonitenolide (13), a previously isolated natural product. The cytotoxic activities of some compounds were determined against A549 and MCF-7 tumor cell lines. The esterified germacranolides 2-6 were selectively cytotoxic against the MCF-7 breast cancer cell line.
A New Cacospongionolide Inhibitor of Human Secretory Phospholipase A2 from the Tyrrhenian Sponge Fasciospongia cavernosa and Absolute Configuration o…
1998
A new inhibitor of human secretory phospholipase A2 (PLA2), cacospongionolide E (4a), has been isolated from the Tyrrhenian sponge Fasciospongia cavernosa. The structure was proposed on the basis of spectroscopic data and by chemical transformations. The absolute configuration of cacospongionolides 2a-4a was established using the modified Mosher's method. Cacospongionolide E was the most potent inhibitor toward human synovial PLA2, showing higher potency than the reference compound manoalide and exerting no signs of toxicity on human neutrophils. It showed high activity in the Artemia salina bioassay and moderate toxicity in the fish (Gambusia affinis) lethality assay.
Sesquiterpenoids from the Endophytic Fungus Rhinocladiella similis
2019
Ten new sesquiterpenoid derivatives, rhinomilisins A-J (1-10), along with six known analogues (11-16), were isolated from the mangrove-derived endophytic fungus Rhinocladiella similis. The structures of the new compounds were elucidated by their NMR and MS data, while the absolute configuration of 3 and 6 was determined by X-ray crystallographic analysis and Mosher's method, respectively. All isolated compounds (1-16) were evaluated for their cytotoxicity against the mouse lymphoma cell line L5178Y, and compounds 1, 7, and 15 showed moderate activity with IC50 values of 5.0, 8.7, and 24.4 μM, respectively.
Metal-Controlled Magnetoresistance at Room Temperature in Single-Molecule Devices
2017
The appropriate choice of the transition metal complex and metal surface electronic structure opens the possibility to control the spin of the charge carriers through the resulting hybrid molecule/metal spinterface in a single-molecule electrical contact at room temperature. The single-molecule conductance of a Au/molecule/Ni junction can be switched by flipping the magnetization direction of the ferromagnetic electrode. The requirements of the molecule include not just the presence of unpaired electrons: the electronic configuration of the metal center has to provide occupied or empty orbitals that strongly interact with the junction metal electrodes and that are close in energy to their F…
Qualitative differences in the exploration of upright and upside-down faces in four-month-old infants : An eye-movement study
2006
The goal of this study was to test if apprentice readers (6-7 to 7-8 years old) and beginner readers (8-9 to 10-11 years old) perceive syllabic units in written words. The paradigm of illusory conjunctions was used because it can determine the infra-lexical units identified at the first steps of the written stimuli process. Two experiments were conducted on children from the first (6-7 years old) to the last years (10-11 years old) of the learning-to-read process. Results have shown that children perceive syllables in letter sequences as soon as the end of the first year of the learning-to-read process. The perception of these units is the result of two information sources: the syllabic pho…
Objectively Measured Physical Activity and Changes in Life-Space Mobility Among Older People
2015
Background Our aim was to study the relationship between objectively measured physical activity and subsequent changes in life-space mobility over 2 years among older people. Life-space mobility refers to the area a person moves through in daily life, taking into account frequency, and need of assistance. Life-space mobility and physical activity correlate, but whether different intensities of objectively assessed physical activity predicts decline in life-space mobility is not known. Methods Prospective cohort study of the "Life-space Mobility in Old Age" (LISPE) project accelerometer substudy. Participants were community-dwelling older people aged 75-90 (n = 164). Life-space mobility was …
Task Modifications in Walking Postpone Decline in Life-Space Mobility Among Community-Dwelling Older People: A 2-year Follow-up Study
2017
Background Task modification refers to performing a task differently than before. While task modification in walking may be a sign of looming walking difficulty, it may also be adaptive in and postpone the decline in life-space mobility. However, this has not been studied. This study examined whether changes in life-space mobility over a 2-year period differ between people who at baseline report no walking difficulty and no task modification, those who report no walking difficulty but task modification, and those who report walking difficulty. Methods Community-dwelling people aged 75–90 years were interviewed face-to-face at baseline (N = 848), and over phone one (n = 816) and two (n = 761…
Characterization of DNA adducts at the bay region of dibenz[a,h]anthracene formed in vitro
1993
Bay region diolepoxide-DNA adducts of dibenz[a,h]anthracene (DBA) formed in vitro were identified and their absolute stereochemistry was assigned. After activation of [5,12-14C]DBA with liver microsomes obtained from Aroclor 1254 treated male Sprague-Dawley rats in the presence of calf thymus DNA for 1 h, the amount of DNA adducts was found to be 9.9 +/- 2.4 pmol/mg DNA, calculated on the basis of the portion of radioactivity eluted from the HPLC reversed-phase column with a water/acetonitrile gradient. Bay region diolepoxide-DNA adducts represented 27.5% of radioactivity associated with DNA adducts. The absolute configuration of the various adducts was determined from the reaction of the (…
The impact of structural and functional characteristics of social relations as determinants of functional decline.
2004
Objectives This study examines whether aspects of social relations at baseline are related to functional decline at 5-year follow-up among nondisabled old men and women. Methods The investigation is based on baseline and follow-up data on 651 nondisabled 75-year-old persons in Jyvaskyla (Finland) and Glostrup (Denmark). The analyses are performed separately for men and women. Possible selection problems were considered by using three outcome measures: first, functional decline among the survivors (n = 425); second, functional decline, including death, assuming that death is part of a general decline pattern (n = 565); and third, mortality (n = 651). Social relations were measured at baselin…