216 research outputs found
Quenching of excited carbonyl triplets by benzene derivatives
Se ha medido la velocidad de desactivación de tripletes carbonilicos (biacetilo, bencilo, benzofenona y 4-metil-2-pentanona) por una serie d,e derivados del benceno. Los resultados pueden ser interpretados por un mecanismo de transferencia de carga. Los compuestos con hidrógenos lábiles (i.e.cumeno) muestran una mayor reactividad. La abstracción de hidrógeno ocurre desde el complejo de transferencia de carga. La desactivación del triplete de la 4-metil-2-pentanona fue medida entre - 5 y 70°C. Las energias de activación obtenidas variaron entre 8.1 kcal (para el cumeno) y 10 kcal (para el benceno)
Dizajniranje i sinteza novih derivata tiofenkarbohidrazida, tienopirazola i tienopirimidina s antioksidativnim i antitumorskim djelovanjem
2-Amino-5-acetyl-4-methyl-thiophene-3-carboxylic acid ethyl ester (1) and 5-acetyl-2-amino-4-methylthiophene-3-carbohydrazide (2) were synthesized and used as starting materials for the synthesis of new series of 1-(5-amino-4-(3,5-dimethyl-1H-pyrazole-1-carbonyl)-3-methylthiophen-2-yl) ethanone (3a), 1-(5-amino-4-(4-chloro-3,5-dimethyl-1H-pyrazole-1-carbonyl)-3-methylthiophen-2-yl) ethanone (3b), 1-(4-methyl-2-amino-5-acetylthiophene-3-carbonyl) pyrazolidine-3,5-dione (4), (Z)-N\u27-(4-methyl-2-amino-5-acetylthiophene-3-carbonyl) formohydrazonic acid (5a), (Z)-ethyl-N\u27-(4-methyl-2-amino-5-acetylthiophene-3-carbonylformo hydrazonate (5b), 6-acetyl-3-amino-2,5-dimethylthieno2,3-dpyrimidin-4(3H)-one (8), 5-methyl-3-amino-2-mercapto-6-acetylthieno2,3-dpyrimidin-4(3H)-one (10) and 5-methyl-6-acetyl-2-thioxo-2,3-dihydrothieno2,3-dpyrimidin-4(1H)-one (12) as potential antioxidant and antitumor agents. Pharmacological results showed that compounds 6a, 6b, 8, 10 and 12 exhibited promising antitumor and antioxidant activity.Etilni ester 2-amino-5-acetil-4-metil-tiofen-3-karboksilne kiseline (1) i 5-acetil-2-amino-4-metiltiofen-3-karbohidrazid (2) sintetizirani su i upotrebljeni kao reaktanti u sintezi novih spojeva 1-(5-amino-4-(3,5-dimetil-1H-pirazol-1-karbonil)-3-metiltiofen-2-il) etanona (3a), 1-(5-amino-4-(4-klor-3,5-dimetil-1H-pirazol-1-karbonil)-3-metiltiofen-2-il) etanona (3b), 1-(4-metil-2-amino-5-acetiltiofen-3-karbonil) pirazolidin-3,5-diona (4), (Z)-N\u27-(4-metil-2-amino-5-acetiltiofen-3-karbonil) formohidrazonske kiseline (5a), (Z)-etil-N\u27-(4-metil-2-amino-5-acetiltiofen-3-karbonilformo hidrazonata (5b), 6-acetil-3-amino-2,5-dimetiltieno2,3-dpirimidin-4(3H)-one (8), 5-metil-3-amino-2-merkapto-6-acetiltieno2,3-dpirimidin-4(3H)-ona (10) i 5-metil-6-acetil-2-tiokso-2,3-dihidrotieno2,3-dpirimidin-4(1H)-ona (12) kao potencijalnih antioksidansa i citostatika. Farmakološka ispitivanja ukazuju na to da spojevi 6a, 6b, 8, 10 i 12 imaju značajno antitumorsko i antioksidativno djelovanje
High-volume infiltration analgesia in bilateral hip arthroplasty: A randomized, double-blind placebo-controlled trial
Study on cosmogenic activation above ground for the DarkSide-20k project
The activation of materials due to the exposure to cosmic rays may become an
important background source for experiments investigating rare event phenomena.
DarkSide-20k is a direct detection experiment for galactic dark matter
particles, using a two-phase liquid argon time projection chamber filled with
49.7 tonnes (active mass) of Underground Argon (UAr) depleted in 39Ar. Here,
the cosmogenic activity of relevant long-lived radioisotopes induced in the
argon and other massive components of the set-up has been estimated; production
of 120 t of radiopure UAr is foreseen. The expected exposure above ground and
production rates, either measured or calculated, have been considered. From the
simulated counting rates in the detector due to cosmogenic isotopes, it is
concluded that activation in copper and stainless steel is not problematic.
Activation of titanium, considered in early designs but not used in the final
design, is discussed. The activity of 39Ar induced during extraction,
purification and transport on surface, in baseline conditions, is evaluated to
be 2.8% of the activity measured in UAr from the same source, and thus
considered acceptable. Other products in the UAr such as 37Ar and 3H are shown
to not be relevant due to short half-life and assumed purification methods
Antioxidant and free radical scavenging effects in extracts of the medicinal herb Achyrocline satureioides (Lam.) DC. ("marcela")
Solvation Dynamics of the Fluorescent Probe PRODAN in Heterogeneous Environments: Contributions from the Locally Excited and Charge-Transferred States
L\u2019uso del Mini Mental State Examination e dell\u2019Esame Neuropsicologico Breve come strumenti di screening neuropsicologico
La valutazione neuropsicologica
\ue8 ritenuta oggi indispensabile per la corretta diagnosi in
ambito neurologico e geriatrico. Esistono numerosi strumenti
utilizzabili dal neuropsicologo per stilare il profilo
neuropsicologico del paziente. La valutazione prevede due
fasi: lo screening e l\u2019approfondimento. Obiettivo. Scopo della
presente ricerca \ue8 il confronto tra due strumenti di screening
neuropsicologico comunemente utilizzati: il \u201cMini Mental
State Examination\u201d e l\u2019\u201cEsame Neuropsicologico Breve\u201d.
Metodo. Lo studio ha preso in esame lo screening
neuropsicologico di 56 pazienti con esiti di ictus, degenti
presso l\u2019U.O. Neuroriabilitazione, FSM di Lumezzane.
I pazienti sono stati suddivisi in tre gruppi, a seconda della
localizzazione della lesione cerebrale (destra, sinistra,
multinfartuale). Risultati. I risultati mostrano che non ci sono
differenze significative tra i vari gruppi patologici, con
l\u2019impiego del MMSE come test di screening. Grazie alla
maggiore completezza dello strumento, ENB \ue8 invece in grado
di rilevare maggiori differenze, ma soltanto a livello
descrittivo: per esempio emergono maggiori errori nelle prove
visuo-spaziali nei pazienti con lesione destra, mentre i pazienti
con lesione sinistra hanno una prestazione inferiore
nella memoria di prosa. Conclusioni. Dai risultati emerge
il problema della sensibilit\ue0 della valutazione neuropsicologica
di screening nei pazienti con esiti di tipo vascolare; entrambi
gli strumenti appaiono inadeguati nel differenziare pazienti
con diverse lesioni cerebrali; viene inoltre considerata
la tempistica di somministrazione degli stessi nei pazienti
in fase post-acuta
Solubilidad de naftaleno y antraceno en n-alcanos
En este trabajo se determina la energía libre molar estándar del naftaleno y antraceno en soluciones de n-pen-tano, n-heptano, n-dodecano y n-hexadecano. Los resultados indican que μ° decrece cuando el tamaño del solvente aumenta. La variación, que es mayor cuando las concentraciones se expresan en fracciones molares, se atribuyen a variaciones conformacionales del solvente
Contaminación interior de viviendas: III Aplicabilidad del modelo simplificado de un compartimiento
A partir de mediciones de acumulación y decaimiento de las concentraciones de CO en diferentes partes de una vivienda, se concluye que el modelo simplificado de un compartimento es adecuado para predecir los niveles de contaminación interior. El volumen de dispersión, a considerar, debe incluir el recinto donde se ubica la fuente emisora, y a todos aquellos espacios conectados a él por puertas abiertas
Deactivation of Pyrene Derivatives by Nitroxides in AOT Reverse Micelles. Dependence of Quenching Efficiency on the Probe and Quencher Location in the Microaggregates
- …