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High efficiency electroluminescence (EL) in organic light emitting diodes (OLED) was achieved using cyclometallated platinum(II) complexes as new phosphorescent emitters. OLEDs containing bis[2-(2-thienyl)pyridine]platinum(II) [Pt(thpy)2] or bis[2-(5-trimethylsilanyl-2-thienyl)-pyridine]platinum(II) [Pt(thpy-SiMe3)2] show a high external EL quantum yield reaching 5.4 and 11.5% photon/electron, respectively. Both electroluminescent spectra fall in the “amber” color region defined by the automotive lighting standards; specifically the CIE coordinates are (0.58; 0.42) for Pt(thpy)2 and (0.60; 0.39) for Pt(thpy-SiMe3)2.

An HIV incidence estimation was performed among men who have sex with men (MSM), drug users (DUs), sex workers (SWs), and pregnant women (PW) from Argentina. Volunteers older than 18 years old without a previous HIV-positive diagnosis were included. HIV-positive samples were analyzed by the Serological Testing Algorithm for Recent HIV Seroconversion (STARHS) to estimate incidence. By partial RT-PCR and sequencing of the HIV pol gene, an HIV subtype and resistance profile were determined. A total of 12,192 volunteers were recruited from October 2006 to September 2008. A higher HIV prevalence was detected among trans SWs (33.9%, 38/112), male SWs (10.8%, 12/111), and MSM 10.4% (161/1549). HIV incidence estimates by STARHS was also higher on trans SWs (11.31 per 100 person-years), male SWs (6.06 per 100 person-years), and MSM (6.36 per 100 person-years). Antiretroviral primary resistant mutations were detected in 8.4% of the study group, with a higher frequency in female DUs (33.3%). Phylogenetic analysis showed that 124 (57.9%) samples were subtype B, 84 (39.3%) intersubtype BF recombinants, 5 (2.3%) subtype C, and 1 (0.5%) subtype F in the pol region. Subtype B was most commonly found in MSM and male SWs whereas the intersubtype BF recombinant was more prevalent in female DUs, female SWs, and PW. Given the high HIV prevalence and incidence found in most of these groups, monitoring the continuing spread of the HIV epidemic is essential for determining public health priorities, assessing the impact of interventions, and estimating current and future health care needs.

Walnut and almond kernels are highly nutritious mainly due to their high oil contents. In this study, 32 factorial experimental designs were used to optimize processes for oil extraction by screw-pressing at industrial scale. Experimental designs included seed moisture content (SMC), and restriction die (RD) as the main processing parameters. Theoretical models were scanned against experimental data in order to optimize oil extraction conditions. The response variables analyzed were oil yield (OY), fine solid content (FC) in oil, and oil quality parameters. Fitted models for OY indicated maximum predicted values similar to the highest experimental values. Walnut oil extractions showed a maximum OY (84.5 ± 2.3 %) at 7.21% SMC, and 10 mm RD. For almond kernels, maximum OY (71.9 ± 3.5%) was obtained at 9.42% SMC, and 12 mm RD. Chemical quality parameters from both oils were in the ranges stated in Codex (FAO/WHO) standards for virgin (non-refined) oils. Extracción de aceite de nuez y almendra a escala industrial: efecto de parámetros del proceso sobre el rendimiento y la calidad del aceite. La nuez y almendra son frutos sumamente nutritivos debido a su alto contenido de aceite. Mediante un diseño experimental de tipo factorial 32 se optimizó el proceso de extracción de estos aceites con prensa de tornillo a escala industrial. Las variables de proceso analizadas fueron el contenido de humedad de la semilla (CHS) y el diámetro de reducción (DR). Los modelos ajustados para rendimiento de aceite (RA) indicaron valores máximos predichos similares a los valores experimentales. Las extracciones de aceite de nuez mostraron un RA máximo (84,5 ± 2,3%) a 7,21% CHS, y 10 mm DR. Para almendra, se obtuvo un máximo de RA (71,9 ± 3,5%) con 9,42% de CHS y 12 mm de DR. Los parámetros de calidad química de ambos aceites se encontraban en los rangos establecidos en las normas del Codex (FAO / OMS) para aceites vírgenes (no refinados).

High efficiency electrophosphorescence (EPH) in organic light-emitting devices was achieved employing a cyclometallated platinum [Pt(II)]-complexes-doped blend of N,N-'-diphenyl-N,N-'-bis(3-methylphenyl)-1,1'-biphenyl-4,4' diamine and bisphenol-A-polycarbonate as the emitting layer. Using bis-[2-(5-trimethylsilanyl-thiophen-2-yl)-pyridine] Pt(II) [Pt(thpy-SiMe3)] as a phosphorescent dopant, a maximum EPH external quantum efficiency of 11.5+/-0.5% photons/carrier was achieved with a three-fold lower roll-off factor at increasing current density, compared with commonly used Pt-based dye 2,3,7,8,12,13,17,18-octaethyl-21H, 23H-porphine platinum (II) (PtOEP). The emission spectrum of the device peaking at congruent to590 nm shifts the chromaticity coordinates toward the orange relative to the PtOEP-based devices.

SummaryPhotosynthetic oxygen evolution by eight month old plants of the Coffea arabica hybrids H-421 (cv. Yellow Catuai × cv. Timor Hybrid) and H-430 (cv. Red Catuai × cv. Timor Hybrid), a Catimor progeny, and one line of cv. Red Catuai was followed polarographically during a dehydration/rehydration cycle. Fully hydrated plants showed a maximum photosynthetic rate (Amax) in the range of 20.6 to 34.6 µmol m−2 s−1 and an apparent quantum yield of 0.074 to 0.086. During dehydration Amax steadily decreased as the water potential declined. Changes were not found among the slope and the intercept values, with the exception of the slope value of hybrid H-421. The recovery was regained 96.0, 96.5, 85.0 and 78.0 h after rehydration for the genotypes Catimor, H-430, Catuai and H-421, respectively. In response to stress, the mesophyll resistance restricts carbon dioxide fixation, with after-effects of variable duration.

A Questionnaire on sleep and vigilance disorders has been developed by the Italian Association of Sleep Medicine to help the occupational health physicians in screening for sleep disorders. Aim of this study was to compare the Questionnaire with standardized questionnaires for sleepiness and sleep apnea and with a polysomnographic evaluation. Four hundred sixty-three (463#) commercial bus drivers (454M, 9F; mean age +/- S.D. 41.6 +/- 8.1 yrs; mean body mass index 26.2 +/- 3.6 kg/m2) underwent clinical evaluation that included the Italian Association of Sleep Medicine Questionnaire on sleep and vigilance disorders and two standardized questionnaires (Berlin Questionnaire and Epworth Sleepiness Scale). According to the Italian Association of Sleep Medicine Questionnaire on sleep and vigilance disorders 40 subjects presented an high risk for sleep disturbance and in 28 subject the questionnaires were concordant. Preliminary results (16 patients) showed an high rate of concordance between questionnaire and PSG. These data strongly suggest that sleep disorders and symptoms, that are frequent in a population of professional bus drivers, should be better evaluated during occupational health visit.

Cardiac rehabilitation after a myocardial infarction has been shown to improve exercise capacity. Beta blockade has been shown to be effective in treating angina and reducing mortality, but studies are controversial as to whether beta-blockade therapy attenuates the effects of training. We attempted to study the effects of beta blockade (metoprolol) on the response to training in patients enrolled in a cardiac rehabilitation program after an uncomplicated myocardial infarction. We studied 27 patients with a recent uncomplicated myocardial infarction who were subdivided in two groups: Group 1 (13 patients) not taking a beta blocker, and Group 2 (14 patients) taking metoprolol (mean 142 +/- 57 mg daily). All patients underwent a maximal cardiopulmonary exercise test before and after a 3-month training program. The training intensity was designed to approximate the ventilatory threshold. Results showed an increase in peak VO2 in both Group 1 (27%, p < 0.01) and Group 2 (33%, p < 0.001), and an increase in VO2 at the ventilatory threshold (39% in Group 1 and 28% in Group 2, p < 0.01). The mean changes in exercise capacity were not different between groups. It was concluded that metoprolol did not influence the beneficial effects of a cardiac rehabilitation program in postmyocardial infarction patients.

1. A study was conducted to evaluate how body weight and age of each female are related to the number and physical and chemical characteristics of the eggs produced throughout a breeding season in a captive-bred population of Greater Rheas (Rhea americana). 2. Reproductive performance of 15 females of three age classes (5 individuals per class) was monitored; female body weight was recorded before laying-onset. All the eggs laid were collected and identified, and different morphometric variables, percentage of components and fatty acid composition were determined. 3. The earlier the female started egg-laying, the longer the laying period and the greater the overall number of eggs produced. The onset of egg-laying in turn seemed to be related to the attainment of a high body weight. 4. Except for length, the values of the morphometric variables of the egg and unsaturated fatty acids (palmitoleic, oleic and linoleic) increased with female age. 5. High body weight was associated with low palmitic and palmitoleic fatty acids and high linoleic, linolenic and total unsaturated fatty acids. 6. Live weight and age of females can determine several physical and chemical characteristics of eggs.

Background Retinal abnormalities, particularly arteriolar narrowing, are powerful predictors of cardiovascular events. The precision of internists and ophthalmologists in the assessment of retinal vessels widths has been disputed but not evaluated against a technology of edge detection. Methods Fifty-two patients with hypertension had optic fundi examination done by an internist and an ophthalmologist, and had retinographies taken and digitized to determine vessel diameters by a new technology of edge detection (microdensitometric method). Physicians asserted the presence of arteriolar narrowing (≤0.67) through direct ophthalmoscopy and projected retinography. The microdensitometric method measures automatically the vessel widths based on the subpixel resolution of the edge of vessel walls. Sensitivity (SE), specificity (SP), positive (PPV) and negative predictive values (NPV), and kappa statistics were calculated, taken the microdensitometric method as reference. Results The performance of the direct examination by the internist to detect arteriolar narrowing was SE: 68.7 (67.0–70.4); SP: 72.7 (68.0–77.4); PPV: 88.0 (85.9–90.0); and NPV: 44.4 (41.5–47.4). For the ophthalmologist the figures were: SE: 74.4 (72.9–75.7); SP: 53.8 (49.8–57.8); PPV: 82.9 (81.3–84.4); and NPV: 41.2 (38.0–44.3). Kappa statistics were 0.34 (0.07–0.62) for the internist, and 0.26 (−0.03–0.53) for the ophthalmologist. Conclusions The performance of internists and ophthalmologists to detect hypertensive microangiopathy based on low arteriolar venous ratio is low and casts doubt about the usefulness of this examination in clinical practice.

1. Eggs from 4 farmed populations of Lesser Rhea (Pterocnemia pennata) were studied to determine their physical and chemical characteristics. 2. None of the physical variables (weight of whole egg, yolk, albumen and shell; proportion of yolk based on egg content; proportion of shell based on entire egg weight; volume; density) showed significant differences between populations. 3. Among chemical variables, moisture, both saturated fatty acids (palmitic 16 : 0 and stearic 18 : 0), one monounsaturated fatty acid (palmitoleic 16:1), and one polyunsaturated fatty acid (arachidonic 20 : 4), did not differ between populations, whereas other variables (protein, lipid and ash contents; fatty acids: oleic 18 : 1, linoleic 18 : 2, linolenic 18 : 3; PUFA; PUFA/SFA; cholesterol) differed significantly.

1. Eggs from wild and captive populations of Greater Rhea (Rhea americana) were studied to determine their physical and chemical characteristics. 2. Significant differences were found among populations in almost all chemical parameters studied, whereas within physical parameters only shell weight (as a proportion of the entire egg) and density showed differences. 3. Eggs from wild populations had the highest protein and linolenic acid and the lowest total lipid contents, while cholesterol levels of these eggs and of those from the largest captive area were the lowest.

Interest in tissue oxygen (PtiO2) monitoring is increasing. However the exact interactions between ptiO2, systemic and cerebral variables are a matter of debate. Particularly, the relationship between ptiO2, cerebral oxygen supply and consumption needs to be clarified. We designed a model to achieve progressive Cerebral Blood Flow (CBF) reduction through 3 steps: 1. baseline, 2. CBF between 50–60% of the baseline, 3. CBF < 30% of the baseline. In 7 pigs, under general anaesthesia, Cerebral Perfusion Pressure (CPP) and CBF were reduced through the infusion of saline in a lateral ventricle. PtiO2 and CBF were monitored respectively through a Clark electrode (Licox, GMS) and laser doppler (Peri-Flux). Blood from superior sagittal sinus and from an arterial line was simultaneously drawn to calculate the artero-venous difference of oxygen (AVD02). Brain oxygen supply was calculated by multiplying relative CBF change and arterial oxygen content. Pti02 reflected CBF reductions, as it was 27.95 (±10.15) mmHg during the first stage of intact CBF, declined to 14.77 (±3.58) mmHg during the first CBF reduction, declined to 3.45 (±2.89) mmHg during the second CBF reduction and finally fell to 0 mmHg when CBF was completely abolished. CBF changes were also followed by a decline in 02 supply and a parallel increase in AVD02. Conclusion: this model allows stable and reproducible steps of progressive CBF reduction in which ptiO2 changes can be studied together with oxygen supply and consumption.

Delayed graft function (DGF) is a relatively common complication after cadaveric renal transplantation. The adverse effect of DGF on long-term graft survival has lead to intensive efforts to reduce ischemic graft injury. In this study we examined the effects of a new protective treatment based on insulin growth factor (IGF)-I. We evaluated the impact of the treatment on renal recovery and on the nephrotoxicity that is a common side effect of mainstream immunosuppressants. Because therapy with IGF-I or the analog des(1-3)IGF-I is effective in treating experimental ischemic renal failure, these peptides may be useful as perspective clinical treatments.We have addressed three areas relating to the potential use of IGF-I and its analog des(1-3)IGF-I. First, because of the immunogenic properties of IGF-I, we assessed the effect of des(1-3)IGF-I on the rejection of skin allografts in Lewis rats. Next we determined whether treatment with des(1-3)IGF-I influences the early function of transplanted kidneys in a model of DGF induced by a combination of warm and cold ischemia. Finally we tested whether IGF-I protects against acute cyclosporine nephrotoxicity.Des(1-3)IGF-I did not accelerate the rejection of the skin grafts (P=0.57). The administration of this peptide in a model of syngenic renal transplant improved the early function of the graft. Postoperative values of creatinine and blood urea nitrogen were significantly better (P0.05) in treated animals. IGF-I also ameliorated the nephrotoxicity of cyclosporine, with better values of creatinine and blood urea nitrogen (P0.05).In evaluating this study it should be recognized that the animal models studied, although widely used, differ from the human condition. However, IGF-I and des(1-3)IGF-I exhibit properties that strongly suggest their value in preventing clinical DGF, and they deserve further studies.

The aims of this study were to determine and compare the antioxidant effect of essential oils from Thymus vulgaris, Laurus nobilis, Foeniculum vulgare, Eucalyptus globules, Tagetes minuta, Satureja parvifolia and Lippia polystachya in soybean oil. The concentrations of volatile oils in soybean oil were 0.1% and 0.02%. The antioxidant activity was measured by peroxide values. Thymus vulgaris and L. nobilis essential oils exhibited a significant antioxidant activity, followed by F. vulgare and E. globules in a decreasing order. Tagetes minuta, S. parvifolia and L. polystachya had not effect, and their contribution to the stability of soybean oil was negligible. Los objetivos de este estudio fueron determinar y comparar el efecto antioxidante de los aceites esenciales de Thymus vulgaris, Laurus nobilis, Foeniculum vulgare, Eucalyptus globulus, Tagetes minuta, Satureja parvifolia y Lippia polystachya en el aceite de soja. Las concentraciones de las esencias en el aceite de soja fueron 0.1% y 0.02%. La actividad antioxidante fue medida por los valores de peróxido. Los aceites esenciales de T. vulgaris y L nobilis exhibieron una significativa acción antioxidante seguidos, en orden decreciente, por F. vulgare y E. globulus. Las esencias de T. minuta, S. parvifolia y L polystachya no mostraron efecto antioxidante y su contribución a la estabilidad oxidativa del aceite de soja fue despreciable.

The first act of any photochemical and photophysical process is the absorption of a photon by a molecule (equation (1)). The excited state that $$A+hv\to*A$$ (1) is formed in this way is a high energy, unstable species which must undergo some type of deactivation [1]. As shown in figure 1, excited state deactivation can occur via (i) disappearance of the original molecule and formation of products (photochemical reaction), (ii) emission of light (radiative deactivation, also called luminescence), (iii) degradation of excess energy into heat (nonradiative deactivation), and (iv) some type of interaction with other species present in the solution (quenching processes).

On photosensitization by tris(2,2′-bipyridine)chromium(III), trans -β-styrylnaphthalene undergoes geometrical isomerization and (in the presence of dioxygen) oxidation to benzaldehyde and naphthaldehyde. Whereas oxidation seems to be due to attack by singlet oxygen, isomerization originates from a cationic radical of the olefin, formed in an electron transfer to be excited complex. The reactivity of such a radical is compared with those of triplet excited states and anionic radicals of stilbene derivatives.

SummaryUsing tritiated water and 45Ca as tracers, the effect of the subtending leaf and of water stress on the movement of water and calcium to flower buds of coffee during dormancy release was studied. Either the subtending leaf or water stress enhanced the mobilization of water and calcium towards the flower buds. The mobilization of water and calcium to buds was greater in plants that had experienced a drought period. A water stress period is apparently essential to release the buds from dormancy, but neither the subtending leaf nor the water potential gradient from the leaf subtending the flower bud clearly affected the phenomenon.

To assess left ventricular (LV) diastolic function in patients with hypertension, a Doppler echocardiographic study of transmitral blood flow (TBF) was performed in 46 hypertensive patients (H), 18 without (H1) and 28 with (H2) left ventricular hypertrophy and in 25 age-matched normal subjects (N). All patients showed normal systolic function. The following indices of Doppler TBF were measured: peak flow velocity during early filling (Evel), atrial systole (Avel) and their ratio (E/Avel); area under early filling phase (Earea), area under atrial systole (Aarea), expressed as a percentage of total diastolic area and their ratio (E/Aarea); deceleration half-time (DHT) of early filling phase. When compared with N, H1 and H2 showed significant reductions in early filling indices and an increase in atrial contribution parameters. (Evel = 0.62 +/- 0.1(N), 0.52 +/- 0.1(H1) P less than 0.01, 0.44 +/- 0.1(H2) P less than 0.001; Earea = 56 +/- 5(N), 48 +/- 5(H1) P less than 0.001, 43 +/- 6(H2) P less than 0.001; Avel = 0.49 +/- 0.1(N), 0.59 +/- 0.1(H1) P less than 0.01, 0.69 +/- 0.14(H2) P less than 0.001; Aarea = 26 +/- 5(N), 41 +/- 4(H1) P less than 0.001, 47 +/- 7(H2) P less than 0.001). Also DHT was significantly prolonged, compared with N (80 +/- 12 msec), in H1 (90 +/- 12 msec, P less than 0.01) and H2 (105 +/- 20 msec, P less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

The effect of interfacing fresh pig blood wth polydimethylsiloxane (PDMS) samples of different surface energies and chemistries is presented. PDMS-treated surfaces were obtained using oxygen plasmas. Aging in air produced rather hydrophobic surfaces, although less hydrophobic than the untreated one, due to hydrophobic recovery. Aging in water hindered it, therefore the surface remained hydrophilic. The concentration of albumin and fibrinogen was measured as a function of contact time with fresh pig blood with untreated, treated and aged in air, and treated and aged in water surfaces. The albumin concentration changed in a constant fashion. Fibrinogen depletion was observed for both treated surfaces. In the case of most hydrophobic surface a ‘passivating layer’ was formed. The same effect was not possible for the hydrophilic surface, due to the low albumin/fibrinogen-treated surface fracture energy.