Are probabilities overweighted or underweighted when rare outcomes are experienced (rarely)?

When making decisions involving risky outcomes on the basis of verbal descriptions of the outcomes and their associated probabilities, people behave as if they overweight small probabilities. In contrast, when the same outcomes are instead experienced in a series of samples, people behave as if they underweight small probabilities. We present two experiments showing that the existing explanations of the underweighting observed in decisions from experience are not sufficient to account for the effect. Underweighting was observed when participants experienced representative samples of events, so it cannot be attributed to undersampling of the small probabilities. In addition, earlier samples predicted decisions just as well as later samples did, so underweighting cannot be attributed to recency weighting. Finally, frequency judgments were accurate, so underweighting cannot be attributed to judgment error. Furthermore, we show that the underweighting of small probabilities is also reflected in the best-fitting parameter values obtained when prospect theory, the dominant model of risky choice, is applied to the data

Lattice sites of ion-implanted Li in diamond

Published in: Appl. Phys. Lett. 66 (1995) 2733-2735 citations recorded in [Science Citation Index] Abstract: Radioactive Li ions were implanted into natural IIa diamonds at temperatures between 100 K and 900 K. Emission channelling patterns of a-particles emitted in the nuclear decay of 8Li (t1/2 = 838 ms) were measured and, from a comparison with calculated emission channelling and blocking effects from Monte Carlo simulations, the lattice sites taken up by the Li ions were quantitatively determined. A fraction of 40(5)% of the implanted Li ions were found to be located on tetrahedral interstitial lattice sites, and 17(5)% on substitutional sites. The fractions of implanted Li on the two lattice sites showed no change with temperature, indicating that Li diffusion does not take place within the time window of our measurements.

Composição bromatológica de silagens de híbridos de sorgo cultivados em diferentes densidades de plantas.

Avaliou-se a composição bromatológica das silagens de dois híbridos de sorgo, AG-2005 (duplo propósito) e VOLUMAX (forrageiro), cultivados nos espaçamentos de 0,50; 0,75 e 1,00 m, resultando nas densidades de 140.000; 186.666 e 280.000 plantas por ha, respectivamente. A silagem do híbrido AG-2005 apresentou matéria seca (MS) superior no espaçamento de 1,00 m e foi mais elevada ao da silagem de VOLUMAX em todos os espaçamentos. A proteína bruta (PB) elevou-se com a redução dos espaçamentos (6,6; 6,8 e 8%, respectivamente), com maior valor médio no AG-2005 (7,7 vs 6,5%). A fibra em detergente neutro (FDN) foi menor no AG-2005 (59,25 vs 62,3%) e no espaçamento 0,75 m. Para fibra em detergente ácido (FDA) ocorreu diferença entre os dois híbridos no espaçamento 0,5 m, sendo de 33,5 e 39,3 %, respectivamente, para o AG-2005 e VOLUMAX. O EE apresentou diferença significativa (P < 0,05) entre os dois híbridos no espaçamento 0,75 m, sendo maior no AG-2005 (2,05 vs 1,61%). Conclui-se que o híbrido AG-2005 é mais recomendado para ensilagem, pois a sua silagem apresenta características qualitativas melhores que do VOLUMAX. O espaçamento de 0,5 m é o mais indicado no plantio dos híbridos, pois melhora a composição química das silagens. Chemical composition of silage sorghum hybrids grown at different densities. AbstractT - The objective of the experiment was to evaluate the nutritive value of silages from two sorghum hybrids, AG-2005 (double purpose) and VOLUMAX (forage) cultivated with different row spacings (0.50 m; 0.75 m and 1.00 m), resulting in 140,000; 186,666 e 280,000 plants per ha, respectively. Dry matter content of AG-2005 silage was higher for 1 m row spacing, and was higher than for VOLUMAX silage in all row spacings. Crude protein increased as the row spacing was reduced (6.6; 6.8 and 8%, respectively), with higher average value for AG-2005 (7.7 vs 6.5%). Neutral detergent fiber was lower for AG-2005 (59.25 vs 62.3%) and for .75 m spacing. Acid detergent fiber differed between hybrids in .5 m row spacing, being 33.5 and 39.3%, respectively, for AG-2005 and VOLUMAX. Ether extract was significantly different between hybrids in .5 m row spacing, being higher for AG-2005 (2.05 vs 1.61%). The use of AG-2005 is recommended for silage production due to its better qualitative characteristics than the VOLUMAX. The .5 m row spacing is recommended for both hybrids, since it improves the chemical composition of the silages

CONSUMO E DESEMPENHO DE BOVINOS DE APTIDÃO LEITEIRA EM CONFINAMENTO ALIMENTADOS COM GLICEROL

This study was conducted to evaluate the nutrients intake and the productive performance ofdairy cows and steers fed diets containing glycerol. The animals were distributed in a completely randomized design with factorial arrangement 4 glycerol levels (0, 6, 12 and 24%) x2sexes (steers and cows) and three replications. The consumption of dry matter (DM) crude protein (CP) and non-fiber carbohydrates (NFC) were not affected by inclusion of glycerol in the diets of cows and steers.However, there was a linear decrease in the consumption of neutral detergent fiber (NDF) (g/kg BW) for cows, but it did not affect the consumption of NDF and ethereal extract (EE) for steers when expressed in kg/day, but showed a quadratic response to NDF intake expressed as%BW and a linear decrease for the consumption of EE expressed in g/kgBW0.75 and %BW. The cows showed a higher intake of DM, CP, NDF, NFC, expressed in kg/day, than the steers, when the diets included 6 and 12% glycerol and higher intakes of DM, NDF and NFC, expressed in g/kg/BW0.75, when diet included 6% glycerol. The daily weight gain was not affected by the inclusion of glycerol. We concluded that glycerol can be included up to 24% of total DM of diets ofdairy steers and cows without compromising animal performance

Amorphization of ZnSe by ion implantation at low temperatures

Radioactive Cd and Se ions were implanted into high-resistivity ZnSe single crystals around 60 K and 300 K. Their lattice sites were determined by measuring the channelling and blocking effects of the emitted conversion electrons or positrons directly after implantation and after annealing at different temperatures up to 600 K. Implantation doses were in the range of 3$\times 10^{12}$ - 3$\times10^{13}$/cm$^2$. The experimental results of this emission channelling technique yield a high substitutional fraction of the implanted ions directly after implantation at room temperature. At 60 K the substitutional fraction of implanted ions is highly sensitive to the ion dose. Above a critical dose of around 1.4$\times10^{13}$ Cd/cm$^2$ or 2.1$\times10^{13}$ Se/cm$^2$ the substitutional fraction completely disappears indicating an amorphous surrounding of the probe atom. Damage recovery was observed below room temperature and at an annealing temperature around 500 K. A quantitative analysis of measured channelling yields will be given by comparison with calculated electron channelling profiles based on the dynamical theory of electron diffraction

Carcass characteristics and meat evaluation of Nelore cattle subjected to different antioxidant treatments

Forty Nelore cattle were used to evaluate the effects of supplementation with different antioxidants on carcass characteristics and meat quality of feedlot cattle. Animals were fed Brachiaria brizantha hay and subjected to five treatments (control and four antioxidants: zinc, selenium, vitamin E, and selenium + vitamin E). After a 105-day feeding period, cattle were slaughtered. Tissue composition, as well as carcass proximate composition, color, tenderness, pH, and fatty acid profile were evaluated. Analysis of variance was carried out and means compared by Tukey test at 0.05 probability. The group fed selenium showed the lowest muscle amount (66.61 g/100 g) compared with the other antioxidants evaluated. There was no difference among treatments for bone, fat, and comestible portion percentages as well as muscle:bone, muscle:fat, and comestible portion:bone ratios, with mean values of 16.85 g/100 g, 14.70 g/100 g, 82.99 g/100 g, 4.06, 4.85, and 4.95, respectively. Neither brightness, red, or yellow contents of the meat nor carcass pH were affected by treatments. For tenderness and losses during thawing and cooking, there were no differences among treatments, with averages of 6.43 kgf cm2, 3.22 g/100 g, and 21.15 g/100 g, respectively. Supplementation of Nelore cattle fed Brachiaria brizantha hay with antioxidants do not influence carcass characteristics or meat quality. However, vitamin E supplementation reduces the levels of omega 3 fatty acid, whereas supplementation with selenium + vitamin E promotes an increase in linoleic and palmitoleic acids and a decrease in myristoleic acid, making the supplementation feasible due to the beneficial effects provided by these acids

FARELO DO MESOCARPO DE BABAÇU NA TERMINAÇÃO DE TOURINHOS: CARACTERÍSTICAS DA CARCAÇA E CORTES SECUNDÁRIOS DO TRASEIRO ESPECIAL

We evaluated carcass characteristics, weight and percentage of prepared commercial cuts of the primal pistol cut (PC) of 30 young crossbred bulls fed diets which included replacement levels (0, 25, 50, 70 and 100% of the dry matter, DM) of corn by babassu mesocarp bran (BMB). The experiment was a completely randomized design with six replicates. Slaughter weight was not affected by treatments. Hot and cold carcass weights decreased linearly (P<.05) at 230 g and 250 g, respectively, for each 1 kg of replacement, and hot carcass yield (HC) decreased by 3.2 g/kg of HC for each 1 kg of DM of BMB in the diet (P<0.05). Subcutaneous fat thickness presented a quadratic (P<.05) response with maximum point estimated by the regression equation of 4.29 mm with 33.3% substitution. The proportion of PC of the carcass increased linearly as levels of BMB in the diet increased (P<.05). The percentage of side cut showed a quadratic response (P<.05), with maximum point estimated with 33.3% substitution. The weight of the prepared commercial cuts of the PC, striploin, knuckle and eye round, and the percentage of tenderloin, topside and shank, were influenced by the diet (P<0.05). There was no change in prepared meat cuts yields of PC (73.22%) (P<.05). The use of babassu mesocarp bran to replace corn in cattle finishing diets does not affect the weight and meat yield of the pistol cut, but decreases linearly hot carcass weight, and subcutaneous fat thickness at replacement levels above 33.3%

α\alpha-emission channeling investigations of the lattice location of Li in Ge

The $\alpha$-emission channeling and blocking technique is a direct method for lattice site determination of radioactive atoms in single crystals. Position-sensitive detection of emitted $\alpha$ -particles provides an efficient means of carrying out such experiments at very low doses (10$^{10}$-10$^{11}$ implanted probe atoms per spectrum). Comparison of the experimental data to Monte Carlo simulations of complete two-dimensional channeling patterns (e.g. ±2°C around , and axes, which also includes all relevant planar directions) allows for straight-forward identification and rather accurate quantitative determination of occupied lattice sites, while at the same time the energy spectrum of emitted a particles gives information on the probe atom depth distribution. We illustrate this for the case of ion implanted $^8$Li (t_=0.8 s) in Ge, where we identify mainly tetrahedral Li at room temperature, and bond-centered Li at slightly elevated temperature

Fatty acids profile in meat of steers from different ages and genetic groups finished in feedlot

Foram utilizados 24 bovinos machos castrados, pertencentes a quatro grupos genéticos (&#8541;Charolês (CH) &#8540;Nelore (NE); &#8541;NE &#8540;CH; ¾ CH ¼ NE e ¾ NE ¼ CH) e duas idades (jovem e superjovem), mantidos com dieta composta de silagem de milho e concentrado, com relação volumoso:concentrado de 50:50. As carcaças, após o abate, foram identificadas e resfriadas retirando-se um bife da porção do músculo Longissimus dorsi, que foi seco em estufa, moído, identificado e armazenado para extração dos lipídeos e determinação dos ácidos graxos, realizada em cromatógrafo a gás. Não houve interação significativa categoria &#215; grupo genético para marmoreio, espessura de gordura e relação músculo:gordura, utilizados como co-variáveis. O total de ácidos graxos trans18 nos animais superjovens foi maior (2,46%) que nos jovens (1,87%). A maioria dos ácidos graxos de cadeia curta (75%) e de cadeia média (91,7%) não foi influenciada pelo grupo genético. Os valores de ácido linoléico conjugado (CLA) não diferiram entre os grupos genéticos. Animais com predominância Nelore apresentaram maior grau de saturação nos ácidos graxos (média de 54,7%) em comparação aos de predominância Charolês (média de 49,5%). A relação de ácidos graxos insaturados/saturados nos animais Charolês foi maior que nos animais Nelore.For the conduction of this work, 24 males from four different genetic groups (&#8541;Charolais (CH) &#8540;Nellore (NE); &#8541;NE &#8540;CH; ¾CH ¼NE e ¾NE ¼CH) and two ages: steers and young steers were used. The animals received a diet composed of corn silage and concentrate with roughage:concentrate ratio of 50:50. After slaughter, the carcasses were identified and&#8541; chilled. A steak from the longissimus muscle was collected and dried in stove, grounded, identified and stored for lipid extraction. The fatty acids (FA) determination was performed through gas chromatograph. No significant interaction was observed between category and genetic groups and marbling, fat thickness, muscle:fat ratio, used as co-variables. The total trans18 FA was higher (2.46%) for young steers in relation to steers (1.87%). Most short-chain (75%) and medium-chain (91.7%) FA were not influenced by the genetic group. CLA values did not differ between CH-NE crossbred animals. Animals with NE predominance showed higher saturated FA (average of 54.7%) in relation to CH animals (average of 49.5%). In relation to the unsaturated/saturated ratio, higher value was observed for CH animals

Características da carcaça de Tourinhos Nelore x Limousin alimentados com dietas contendo gérmen de milho integral.

Foram avaliadas as características quantitativas das carcaças de 24 tourinhos Nelore X Limousin submetidos a dietas contendo 0%, 15% e 45% de gérmen de milho integral (GMI), terminados em confinamento, com peso e idade média inicial de 321,25 kg e vinte meses, respectivamente