Cooperative games with size-truncated information

[Eng] We study the marginal worth vectors and their convex hull, the socalled Weber set, from the original coalitional game and the transformed one, which is called the Weber set of level k. We prove that the core of the original game is included in each of the Weber set of level k, for any k, and that the Weber sets of consecutive levels form a chain if and only if the original game is 0-monotone. Even if the game is not 0-monotone, the intersection of the Weber sets for consecutive levels is always not empty, what is not the case for non-consecutive ones. Spanish education system.

Optimized back-focal-plane interferometry directly measures forces of optically trapped particles

Back-focal-plane interferometry is used to measure displacements of optically trapped samples with very high spatial and temporal resolution. However, the technique is closely related to a method that measures the rate of change in light momentum. It has long been known that displacements of the interference pattern at the back focal plane may be used to track the optical force directly, provided that a considerable fraction of the light is effectively monitored. Nonetheless, the practical application of this idea has been limited to counter-propagating, low-aperture beams where the accurate momentum measurements are possible. Here, we experimentally show that the connection can be extended to single-beam optical traps. In particular, we show that, in a gradient trap, the calibration product κ·β (where κ is the trap stiffness and 1/β is the position sensitivity) corresponds to the factor that converts detector signals into momentum changes; this factor is uniquely determined by three construction features of the detection instrument and does not depend, therefore, on the specific conditions of the experiment. Then, we find that force measurements obtained from back-focal-plane displacements are in practice not restricted to a linear relationship with position and hence they can be extended outside that regime. Finally, and more importantly, we show that these properties are still recognizable even when the system is not fully optimized for light collection. These results should enable a more general use of back-focal-plane interferometry whenever the ultimate goal is the measurement of the forces exerted by an optical trap.

Cooperative games with size-truncated information

[Eng] We study the marginal worth vectors and their convex hull, the socalled Weber set, from the original coalitional game and the transformed one, which is called the Weber set of level k. We prove that the core of the original game is included in each of the Weber set of level k, for any k, and that the Weber sets of consecutive levels form a chain if and only if the original game is 0-monotone. Even if the game is not 0-monotone, the intersection of the Weber sets for consecutive levels is always not empty, what is not the case for non-consecutive ones. Spanish education system.

Crystal size distribution of periclase in contact metamorphic dolomite marbles from the southern Adamello Massif, Italy

Crystal size distributions (CSD) of periclase in contact metamorphic dolomite marbles are presented for two profiles near the Cima Uzza summit in the southern Adamello Massif (Italy). The database was combined with geochemical and petrological information to deduce the controls on the periclase-forming reaction. The contact metamorphic dolomite marbles are exposed at the contact of mafic intrusive rocks and are partially surrounded by them. Brucite is retrograde and pseudomorphs spherical periclase crystals. Prograde periclase growth is the consequence of limited infiltration of water-rich fluid at T near 605C. Stable isotope data show depletion in (13)C and (18)O over a narrow region (40 cm) near the magmatic contact, whereas the periclase-forming reaction front extends up to 4 m from the contact. CSD analyses along the two profiles show that the median grain size of the periclase crystals does not change, but that there is a progressively greater distribution of grain sizes, including a greater proportion of larger grains, with increasing distance from the contact. A qualitative model, based on the textural and geochemical data, attributes these variations in grain size to changing reaction affinities along a kinetically dispersed infiltration front. This study highlights the need to invoke disequilibrium processes for metamorphic mineral growth and expands the use of CSDs to systems of mineral formation driven by fluid infiltration.

Bacterial spot and early blight biocontrol by epiphytic bacteria in tomato plants

The objective of this work was to evaluate in vitro and in vivo biocontrol of bacterial spot (Xanthomonas vesicatoria) and early blight (Alternaria solani) by the epiphytic bacteria Paenibacillus macerans and Bacillus pumilus. Tomato plants were previously sprayed with epiphytic bacteria, benzalkonium chloride and PBS buffer and, after four days, they were inoculated with A. solani and X. vesicatoria. To determine the phytopathogenic bacteria population, leaflet samples were collected from each treatment every 24 hours, for seven days, and plated on semi-selective medium. The effect of epiphytic bacteria over phytopathogens was performed by the antibiosis test and antagonistic activity measured by inhibition zone diameter. The epiphytic and benzalkonium chloride drastically reduced the severity of early blight and bacterial spot in comparison to the control (PBS). In detached leaflets, the epiphytic bacteria reduced in 70% the number of phytopathogenic bacteria cells in the phylloplane. The antibiosis test showed that the epiphytic bacteria efficiently inhibit the phytopathogens growth. In all the bioassays, the epiphytic bacteria protect tomato plants against the phytopathogens

Holographic optical tweezers combined with back-focal-plane displacement detection

A major problem with holographic optical tweezers (HOTs) is their incompatibility with laser-based position detection methods, such as back-focal-plane interferometry (BFPI). The alternatives generally used with HOTs, like high-speed video tracking, do not offer the same spatial and temporal bandwidths. This has limited the use of this technique in precise quantitative experiments. In this paper, we present an optical trap design that combines digital holography and back-focal-plane displacement detection. We show that, with a particularly simple setup, it is possible to generate a set of multiple holographic traps and an additional static non-holographic trap with orthogonal polarizations and that they can be, therefore, easily separated for measuring positions and forces with the high positional and temporal resolutions of laser-based detection. We prove that measurements from both polarizations contain less than 1% crosstalk and that traps in our setup are harmonic within the typical range. We further tested the instrument in a DNA stretching experiment and we discuss an interesting property of this configuration: the small drift of the differential signal between traps.

Selection of shrimp breeders free of white spot syndrome and infectious hypodermal and hematopoietic necrosis

The objective of this work was to select surviving breeders of Litopenaeus vannamei from white spot syndrome virus (WSSV) outbreak, adapted to local climatic conditions and negatively diagnosed for WSSV and infectious hypodermal and hematopoietic necrosis virus (IHHNV), and to evaluate if this strategy is a viable alternative for production in Santa Catarina, Brazil. A total of 800 males and 800 females were phenotypically selected in a farm pond. Nested-PCR analyses of 487 sexually mature females and 231 sexually mature males showed that 63% of the females and 55% of the males were infected with IHHNV. Animals free of IHHNV were tested for WSSV, and those considered double negative were used for breeding. The post-larvae produced were stocked in nine nursery tanks for analysis. From the 45 samples, with 50 post-larvae each, only two were positive for IHHNV and none for WSSV. Batches of larvae diagnosed free of virus by nested-PCR were sent to six farms. A comparative analysis was carried out in growth ponds, between local post-larvae and post-larvae from Northeast Brazil. Crabs (Chasmagnathus granulata), blue crabs (Callinectes sapidus), and sea hares (Aplysia brasiliana), which are possible vectors of these viruses, were also evaluated. The mean survival was 55% for local post-larvae against 23.4% for post-larvae from the Northeast. Sea hares showed prevalence of 50% and crabs of 67% of WSSV.

Effects of sample size on the performance of species distribution models

A wide range of modelling algorithms is used by ecologists, conservation practitioners, and others to predict species ranges from point locality data. Unfortunately, the amount of data available is limited for many taxa and regions, making it essential to quantify the sensitivity of these algorithms to sample size. This is the first study to address this need by rigorously evaluating a broad suite of algorithms with independent presence-absence data from multiple species and regions. We evaluated predictions from 12 algorithms for 46 species (from six different regions of the world) at three sample sizes (100, 30, and 10 records). We used data from natural history collections to run the models, and evaluated the quality of model predictions with area under the receiver operating characteristic curve (AUC). With decreasing sample size, model accuracy decreased and variability increased across species and between models. Novel modelling methods that incorporate both interactions between predictor variables and complex response shapes (i.e. GBM, MARS-INT, BRUTO) performed better than most methods at large sample sizes but not at the smallest sample sizes. Other algorithms were much less sensitive to sample size, including an algorithm based on maximum entropy (MAXENT) that had among the best predictive power across all sample sizes. Relative to other algorithms, a distance metric algorithm (DOMAIN) and a genetic algorithm (OM-GARP) had intermediate performance at the largest sample size and among the best performance at the lowest sample size. No algorithm predicted consistently well with small sample size (n < 30) and this should encourage highly conservative use of predictions based on small sample size and restrict their use to exploratory modelling.

Effects of bisoprolol fumarate on left ventricular size, function, and exercise capacity in patients with heart failure: analysis with magnetic resonance myocardial tagging.

BACKGROUND: Recent data suggest that beta-blockers can be beneficial in subgroups of patients with chronic heart failure (CHF). For metoprolol and carvedilol, an increase in ejection fraction has been shown and favorable effects on the myocardial remodeling process have been reported in some studies. We examined the effects of bisoprolol fumarate on exercise capacity and left ventricular volume with magnetic resonance imaging (MRI) and applied a novel high-resolution MRI tagging technique to determine myocardial rotation and relaxation velocity. METHODS: Twenty-eight patients (mean age, 57 +/- 11 years; mean ejection fraction, 26 +/- 6%) were randomized to bisoprolol fumarate (n = 13) or to placebo therapy (n = 15). The dosage of the drugs was titrated to match that of the the Cardiac Insufficiency Bisoprolol Study protocol. Hemodynamic and gas exchange responses to exercise, MRI measurements of left ventricular end-systolic and end-diastolic volumes and ejection fraction, and left ventricular rotation and relaxation velocities were measured before the administration of the drug and 6 and 12 months later. RESULTS: After 1 year, heart rate was reduced in the bisoprolol fumarate group both at rest (81 +/- 12 before therapy versus 61 +/- 11 after therapy; P <.01) and peak exercise (144 +/- 20 before therapy versus 127 +/- 17 after therapy; P <.01), which indicated a reduction in sympathetic drive. No differences were observed in heart rate responses in the placebo group. No differences were observed within or between groups in peak oxygen uptake, although work rate achieved was higher (117.9 +/- 36 watts versus 146.1 +/- 33 watts; P <.05) and exercise time tended to be higher (9.1 +/- 1.7 minutes versus 11.4 +/- 2.8 minutes; P =.06) in the bisoprolol fumarate group. A trend for a reduction in left ventricular end-diastolic volume (-54 mL) and left ventricular end-systolic volume (-62 mL) in the bisoprolol fumarate group occurred after 1 year. Ejection fraction was higher in the bisoprolol fumarate group (25.0 +/- 7 versus 36.2 +/- 9%; P <.05), and the placebo group remained unchanged. Most changes in volume and ejection fraction occurred during the latter 6 months of treatment. With myocardial tagging, insignificant reductions in left ventricular rotation velocity were observed in both groups, whereas relaxation velocity was reduced only after bisoprolol fumarate therapy (by 39%; P <.05). CONCLUSION: One year of bisoprolol fumarate therapy resulted in an improvement in exercise capacity, showed trends for reductions in end-diastolic and end-systolic volumes, increased ejection fraction, and significantly reduced relaxation velocity. Although these results generally confirm the beneficial effects of beta-blockade in patients with chronic heart failure, they show differential effects on systolic and diastolic function.

Long-term close follow-up of chorioretinal lesions in presumed ocular tuberculosis.

PURPOSE: To evaluate the long-term outcome (up to 7 years) of presumed ocular tuberculosis (TB) when the therapeutic decision was based on WHO guidelines. METHODS: Twelve out of 654 new uveitic patients (1998-2004) presented with choroiditis and positive tuberculosis skin test (TST) (skin lesion diameter >15 mm). Therapy was administered according to WHO recommendations after ophthalmic and systemic investigation. The area size of ocular lesions at presentation and after therapy, measured on fluorescein and indocyanine green angiographies, was considered the primary outcome. Relapse of choroiditis was considered a secondary outcome. The T-SPOT TB test was performed when it became available. RESULTS: Visual acuity significantly improved after therapy (p=0.0357). The mean total surface of fluorescein lesions at entry was 44.8 ± 20.9 (arbitrary units) and decreased to 32.5 ± 16.9 after therapy (p=0.0165). The mean total surface of indocyanine green lesions at entry was 24.5 ± 13.3 and decreased to 10.8 ± 5.4 after therapy (p=0.0631). The T-SPOT TB revealed 2 false TST-positive results. The mean follow-up was 4.5 ± 1.5 years. Two relapses out of 10 confirmed ocular TB was observed after complete lesion healing, 2.5 years and 4.5 years after therapy, respectively. CONCLUSIONS: A decrease of ocular lesion mean size and a mean improvement of VA were observed after antituberculous therapy. Our long-term follow-up of chorioretinal lesions demonstrated relapse of ocular tuberculosis in 10% of patients with confirmed ocular TB, despite complete initial retinal scarring.

Am I shrinking? On clothing size and body size.

Comment on: Hughes LA, Schouten LJ, Goldbohm RA, van den Brandt PA, Weijenberg MP. Self-reported clothing size as a proxy measure for body size. Epidemiology. 2009 Sep;20(5):673-6. PMID: 19451821

Antibacterial activity of essential oils on Xanthomonas vesicatoria and control of bacterial spot in tomato

The objective of this work was to evaluate the effects of plant essential oils (EOs) on the growth of Xanthomonas vesicatoria, on bacterial morphology and ultrastructure, and on the severity of tomato bacterial spot. EOs from citronella, clove, cinnamon, lemongrass, eucalyptus, thyme, and tea tree were evaluated in vitro at concentrations of 0.1, 1.0, 10, and 100% in 1.0% powdered milk. The effect of EOs, at 0.1%, on the severity of tomato bacterial spot was evaluated in tomato seedlings under greenhouse conditions. The effects of citronella, lemongrass, clove, and tea tree EOs, at 0.1%, on X. vesicatoria cells were evaluated by transmission electron microscopy. All EOs showed direct toxic effect on the bacteria at a 10%-concentration in vitro. Under greenhouse conditions, the EOs of clove, citronella, tea tree, and lemongrass reduced disease severity. EOs of clove and tea tree, and streptomycin sulfate promoted loss of electron-dense material and alterations in the cytoplasm, whereas EO of tea tree promoted cytoplasm vacuolation, and those of citronella, lemongrass, clove, and tea tree caused damage to the bacterial cell wall. The EOs at a concentration of 0.1% reduce the severity of the disease.

Glibenclamide enhances neurogenesis and improves long-term functional recovery after transient focal cerebral ischemia

Glibenclamide is neuroprotective against cerebral ischemia in rats. We studied whether glibenclamide enhances long-term brain repair and improves behavioral recovery after stroke. Adult male Wistar rats were subjected to transient middle cerebral artery occlusion (MCAO) for 90 minutes. A low dose of glibenclamide (total 0.6mg) was administered intravenously 6, 12, and 24 hours after reperfusion. We assessed behavioral outcome during a 30-day follow-up and animals were perfused for histological evaluation. In vitro specific binding of glibenclamide to microglia increased after pro-inflammatory stimuli. In vivo glibenclamide was associated with increased migration of doublecortin-positive cells in the striatum toward the ischemic lesion 72 hours after MCAO, and reactive microglia expressed sulfonylurea receptor 1 (SUR1) and Kir6.2 in the medial striatum. One month after MCAO, glibenclamide was also associated with increased number of NeuN-positive and 5-bromo-2-deoxyuridine-positive neurons in the cortex and hippocampus, and enhanced angiogenesis in the hippocampus. Consequently, glibenclamide-treated MCAO rats showed improved performance in the limb-placing test on postoperative days 22 to 29, and in the cylinder and water-maze test on postoperative day 29. Therefore, acute blockade of SUR1 by glibenclamide enhanced long-term brain repair in MCAO rats, which was associated with improved behavioral outcome.

Séries temporais de NDVI do sensor SPOT Vegetation e algoritmo SAM aplicados ao mapeamento de cana‑de‑açúcar

O objetivo deste trabalho foi avaliar o mapeamento de área de cana‑de‑açúcar por meio de série temporal, de seis anos de dados do índice de vegetação por diferença normalizada (NDVI), oriundos do sensor Vegetation, a bordo do satélite "système pour l'observation de la Terre" (SPOT). Três classes de cobertura do solo (cana‑de‑açúcar, pasto e floresta), do Estado de São Paulo, foram selecionadas como assinaturas espectro‑temporais de referência, que serviram como membros extremos ("endmembers") para classificação com o algoritmo "spectral angle mapper" (SAM). A partir desta classificação, o mapeamento da área de cana‑de‑açúcar foi realizado com uso de limiares na imagem-regra do SAM, gerados a partir dos valores dos espectros de referência. Os resultados mostram que o algoritmo SAM pode ser aplicado a séries de dados multitemporais de resolução moderada, o que permite eficiente mapeamento de alvo agrícola em escala mesorregional. Dados oficiais de áreas de cana‑de‑açúcar, para as microrregiões paulistas, apresentam boa correlação (r² = 0,8) com os dados obtidos pelo método avaliado. A aplicação do algoritmo SAM mostrou ser útil em análises temporais. As séries temporais de NDVI do sensor SPOT Vegetation podem ser utilizadas para mapeamento da área de cana‑de‑açúcar em baixa resolução.