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1.
Phys Rev Lett ; 131(3): 031802, 2023 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-37540851

RESUMEN

We report the direct observation of muon neutrino interactions with the SND@LHC detector at the Large Hadron Collider. A dataset of proton-proton collisions at sqrt[s]=13.6 TeV collected by SND@LHC in 2022 is used, corresponding to an integrated luminosity of 36.8 fb^{-1}. The search is based on information from the active electronic components of the SND@LHC detector, which covers the pseudorapidity region of 7.2<η<8.4, inaccessible to the other experiments at the collider. Muon neutrino candidates are identified through their charged-current interaction topology, with a track propagating through the entire length of the muon detector. After selection cuts, 8 ν_{µ} interaction candidate events remain with an estimated background of 0.086 events, yielding a significance of about 7 standard deviations for the observed ν_{µ} signal.

2.
Diabetes Res Clin Pract ; 67(3): 267-72, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15713360

RESUMEN

Over 1 year, a survey on contraception and obstetric history was performed on a cohort of 667 Caucasian fertile diabetic women (446, type 1 and 201, type 2) living in Italy. RESULTS: Of these women, 30.4% used hormonal contraceptives, 12.0% intra-uterine device (IUD), 10.7% declared they used no contraception, 47.0% only utilised barrier and/or natural methods. However, irrespective of their previous contraceptive strategy, 7.2% of all the studied population was surgically sterilized during caesarean section. HORMONAL CONTRACEPTION: Of these women, 60.4% was prescribed by a gynaecologist, 11.2% by a diabetologist, 15% by both of them and 13.4% by others. The proportion using oral contraception was similar among types 1 and 2 women (29.4% versus 27.8%, chi(2) = ns). SMOKING HABITS: Of women taking hormonal contraception, 30.0% were smokers. EDUCATIONAL LEVEL: University graduates (37.1%), high school leaves (32.2%), secondary school (28.2%) and primary school leaves (15.5%) used oral contraceptives (OC). OBSTETRIC HISTORY: The mean number of deliveries was 1.14 +/- 1.1, of miscarriages was 1.3 +/- 0.7 and of induced abortions 0.17 +/- 0.5. Planning of at least one pregnancy was reported in 29.4% of patients.


Asunto(s)
Anticoncepción/estadística & datos numéricos , Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Adulto , Estudios de Cohortes , Retinopatía Diabética/epidemiología , Femenino , Geografía , Humanos , Italia , Estado Civil , Fumar/epidemiología , Población Blanca
3.
Biomaterials ; 16(16): 1249-53, 1995 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8589195

RESUMEN

Glasses were prepared by substituting La2O3 or Y2O3 for CaO in glassy wollastonite composition (CaO.SiO2). Their behaviour when they are soaked in a simulated body fluid (SBF) was studied by means of an electron microscope equipped with an energy dispersive system for elemental analysis, and by means of IR spectroscopy. Electron microscopy and energy dispersive microanalysis were performed on samples soaked as polished bulk samples, and IR analysis was on samples soaked as fine powders. A carbonate-containing hydroxyapatite layer is formed when glasses of low La2O3 content are soaked in SBF. When Y2O3-containing glasses are considered, even in the case of small substitution for CaO, the same layer forms only on fracture surfaces. The experimental results agree with the mechanism reported in the literature.


Asunto(s)
Apatitas/química , Materiales Biocompatibles/química , Cerámica/química , Líquidos Corporales/metabolismo , Compuestos de Calcio/química , Microanálisis por Sonda Electrónica , Vidrio/química , Humanos , Técnicas In Vitro , Ensayo de Materiales , Microscopía Electrónica , Modelos Biológicos , Silicatos/química , Espectroscopía Infrarroja por Transformada de Fourier
4.
Biomaterials ; 18(6): 453-8, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9111947

RESUMEN

Glasses were prepared whose composition is defined by the following general formula: (2.5-x)CaO.x/3Y2O3.2SiO2 (0 < or = x < or = 1). Their behaviour when they were soaked in a simulated body fluid (SBF) and their thermal properties (glass transformation and softening temperatures, Tg and Ts respectively) were studied Tg and Ts increase with the Y2O3 content. The trend can be explained on the basis of the increased structural rigidity when Ca2+ ions are substituted by Y2+ ions, because of the formation of stronger bonds to the oxygen. The bioactivity was studied by means of electron microscopy equipped with an energy dispersive system for elemental analysis and IR spectroscopy. All the glasses studied except the one with the greatest amount of Y2O3. x = 1.0, reacted with SBF by forming a calcium phosphate layer. The experimental results suggest that the bioactivity is negatively influenced by the Y2O3 content: the tendency to form a calcium phosphate layer is reduced the greater the amount of CaO substituted. A comparison with literature data indicates that the amount of Y2O3 that can be substituted depends on the CaO content of the base CaO-SiO2 glass. The experimental results are in good agreement with the mechanism reported in the literature. After 7 days soaking, crystalline hydroxyapatite is formed in the Y2O3-free glass and in the glasses of low Y2O3 content (x-0.2).


Asunto(s)
Materiales Biocompatibles , Compuestos de Calcio/química , Vidrio , Óxidos/química , Dióxido de Silicio/química , Itrio/química , Apatitas , Ensayo de Materiales , Microscopía Electrónica , Espectroscopía Infrarroja por Transformada de Fourier , Relación Estructura-Actividad , Termodinámica
5.
Biomaterials ; 17(23): 2247-51, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8968519

RESUMEN

Powdered samples (170-230 mesh) of a glass of composition 1.25CaO.SiO2 were soaked in a simulated body fluid (SBF). The powders were submitted to Fourier transform infrared transmission spectroscopy as coarse powders (such as drawn out from the SBF) and as fine powders (soaked and subsequently ground). Soaked samples were submitted to differential thermal analysis (DTA) and the crystalline phases formed during heating in the DTA apparatus were identified by means of X-ray diffraction analysis. The method appears to be useful in studying the mechanism of deposition of the hydroxyapatite layer. It is documented, by using the same method, that the mechanism involves the reactions of hydrolysis and successive condensation and repolymerization of the silicate substrate. These reactions are very fast. Extensive Ca2+ cation depletion occurs, but appears to be slower.


Asunto(s)
Materiales Biocompatibles/química , Compuestos de Calcio/análisis , Vidrio/química , Óxidos/análisis , Dióxido de Silicio/análisis , Líquidos Corporales/química , Fenómenos Químicos , Química Física , Análisis Diferencial Térmico , Durapatita/análisis , Ensayo de Materiales , Polvos , Soluciones/farmacología , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
7.
J Agric Food Chem ; 47(12): 5252-6, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10606604

RESUMEN

A new supercritical extraction methodology was applied to extract azadirachtin A (AZA-A) from neem seed kernels. Supercritical and liquid carbon dioxide (CO(2)) were used as extractive agents in a three-separation-stage supercritical pilot plant. Subcritical conditions were tested too. Comparisons were carried out by calculating the efficiency of the pilot plant with respect to the milligrams per kilogram of seeds (ms/mo) of AZA-A extracted. The most convenient extraction was gained using an ms/mo ratio of 119 rather than 64. For supercritical extraction, a separation of cuticular waxes from oil was set up in the pilot plant. HPLC and electrospray mass spectroscopy were used to monitor the yield of AZA-A extraction.


Asunto(s)
Insecticidas/aislamiento & purificación , Limoninas , Semillas/química , Árboles , Triterpenos/aislamiento & purificación , Animales , Cromatografía Líquida de Alta Presión , Cromatografía de Gases y Espectrometría de Masas
9.
J Biomed Mater Res ; 32(2): 187-92, 1996 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8884494

RESUMEN

Glasses of the following composition were prepared: (2.5-x)CaO.x/3La2O3.2SiO2 (0 < or = x < or = 1). Their behavior when soaked in a simulated body fluid (SBF) was studied by means of electron microscopy (EM) equipped with an energy-dispersive system (EDS) for elemental analysis, IR spectroscopy, and x-ray diffraction. All the studied glasses react with SBF by forming a calcium phosphate layer. This layer appears to be increasingly thinner with increasing amounts of La2O3 substituted. The experimental results are in good agreement with mechanisms reported in the literature. Moreover they suggest that lanthanum oxide is retained in the layer below the phosphate. After 6 days of soaking, crystalline hydroxyapatite is formed in the case of La2O3 free glass.


Asunto(s)
Compuestos de Calcio , Vidrio , Lantano , Óxidos , Sangre , Líquidos Corporales , Fosfatos de Calcio , Humanos , Microscopía Electrónica , Espectrofotometría Infrarroja , Difracción de Rayos X
10.
Talanta ; 62(3): 523-30, 2004 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-18969327

RESUMEN

Beauvericin (BEA), a supercritical fluid extraction with supercritical carbon dioxide from maize was investigated. Extraction efficiencies under several different extraction conditions were examined. Pressure, temperature, extraction time, organic modifier and water matrix content (10%) were investigated. The best extraction conditions were at a temperature of 60 degrees C, 3200psi, for 30min static extraction time and methanol as modifier solvent. Extraction recovery of 36% without modifier by adding water to the matrix in the extraction vessel (reproducibility relative standard deviations (R.S.D.)=3-5%) were recorded. Extraction recovery of 76.9% with methanol as co-solvent (reproducibility R.S.D.=3-5%) was obtained. Data shows that SFE gives a lower BEA recovery compared to conventional extraction protocol with organic solvents while SFE with modifier and conventional extraction yields are comparable. BEA extract contents were determined by high pressure liquid chromatography (HPLC) with a diode array detector (DAD) at 205nm and BEA peak confirmed by LC-MS. Acetonitrile-water as mobile phase and column C-18 were both tested. Instrumental and analytical parameters were optimized in the range linear interval from 1 to 500mgkg(-1) and reached a detection limit of 2ng.

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