RESUMO
Biologically active saponins were found to be concentrated in the white and green alfalfa leaf protein fractions at levels higher than in the original alfalfa. Coagulation and washing of the leaf protein at pH 8.5 resulted in a fourfold decrease in saponin compared to the protein coagulated at pH 6.0 and washed at pH 4.5. The press cakes from high and low saponin alfalfa retained 65 and 87% of the saponin. Protein fractions prepared from a low saponin alfalfa contained saponin levels less than 0.07%, compared to a saponin level of 1.33% in leaf protein prepared form a high saponin alfalfa. The saponin contents of three varieties of alfalfa sprouts ranged from 1.55 to 7.27% depending upon the maturity of the sprouts. The saponin content rapidly increased after sprouting and reached a maximum after eight days' growth. Both starch and total sugar decreased with the age of the sprouts while fiber increased from 8 to 18.7%.
Assuntos
Análise de Alimentos , Medicago sativa/análise , Proteínas de Plantas/análise , Saponinas/análise , Animais , Concentração de Íons de Hidrogênio , Medicago sativa/toxicidadeRESUMO
Nitrite ion has been identified as the active ingredient of two commercial adulterants that could cause discrepant results between the immunoassay screening and gas chromatographic-mass spectrometric (GC-MS) confirmation of 11-nor-delta9-tetrahydrocannabinol-9-carboxylic acid (THCCOOH) in urine. Procedures to chemically convert the nitrite ion at the beginning of sample preparation for GC-MS analysis may not overcome all nitrite adulteration cases because portions of the THCCOOH might have been lost between the time of sample collection and the time of analysis. This study was conducted to further investigate the influence of both urine sample matrix and the duration of nitrite exposure on nitrite interference of THCCOOH detection. Forty clinical "THC-positive samples" that had been screened and confirmed positive for the presence of THCCOOH were spiked with 0.15M or 0.3M of nitrite. The levels of THCCOOH at various time intervals after nitrite spiking were monitored by instrument-based cannabinoids immunoassays (Syva EMIT d.a.u. and/or Roche Abuscreen ONLINE assays) and by an onsite THC immunoassay (Roche ONTRAK TESTSTIK). Results from this report demonstrate that the two outstanding "urine specimen factors" that dictated the effectiveness of the nitrite adulteration were urinary pH and the original drug concentration before nitrite spiking. Significant decreases in the immunoassay results could be observed within 4 h of nitrite treatment in the majority of samples with acidic urinary pH values. Regardless of their original concentration of THCCOOH (GC-MS ranging from 33 to 488 ng/mL), all of the 20 samples that had acidic pH values gave negative immunoassay results 1 day after nitrite adulteration. In contrast, the immunoassay results of samples with neutral or basic pH values were less affected by nitrite exposure in the same studies. Approximately two-thirds of the samples with pH values greater than 7.0 remained immunoassay-positive 3 days after nitrite spiking. Nevertheless, some of the adulterated urine that showed no change in immunoassay results might exhibit significant decrease in GC-MS recoveries even with bisulfite treatment, collaborating with the observations that a portion of samples screened positive with THC immunoassay in the laboratory could fail to confirm with GC-MS analysis. The decrease or loss of immunoassay detectable cannabinoid cross-reactives in acidic "THC-positive samples" can be attenuated by chemically increasing the pH value of the samples to the basic pH range.
Assuntos
Dronabinol/análogos & derivados , Dronabinol/urina , Contaminação de Medicamentos , Nitritos/química , Detecção do Abuso de Substâncias/métodos , Técnica de Imunoensaio Enzimático de Multiplicação , Reações Falso-Negativas , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Concentração de Íons de HidrogênioRESUMO
A cognitive maze was developed to study perceptual and conceptual processes in the discovery of relationships through inductive inference and flexible shifting of mental sets adaptive to changed problems. For example, the experimenter-tester presents a list of digits in consecutive pairs; subject-testee is asked to select one digit from each pair and tester answers "right" or "wrong" according to whether the choice agrees or disagrees with the hidden principle fixed for that particular problem. After reaching criterion, the principle is stated explicitly, and a new problem involving a different principle (odd or even number, high or low value, simple or double alternation) is presented. In two pilot studies, numbers of trials and errors to criterion correlated strongly with scores on WAIS Arithmetic, Digit Span, and Block Design for a randomly selected heterogeneous group of 10 testees and with course grades for 25 college students. This maze can be administered and scored by computer. Applications are many.
Assuntos
Formação de Conceito , Aprendizagem por Discriminação , Orientação , Resolução de Problemas , Adolescente , Adulto , Humanos , Inteligência , Pessoa de Meia-Idade , Testes Psicológicos , Enquadramento PsicológicoRESUMO
30 adult male white rats were equally divided into control, scopolamine, and electroconvulsive shock groups to learn 20 successive reversal problems in an E-maze for water after 23 1/2 hr. of deprivation. The noncorrection method was used. After 1 mo. of preliminary training, each scopolamine animal received an intraperitoneal injection of 1 mgm of scopolamine hydrobromide per kgm of body weight while each in the shock group was given an ECS of 35 mA for .2 sec. at the end of every 10 daily trials. When a rat obtained 9 correct of 10 trials, the goal was switched to the opposite side of the maze. Controls were much superior to both experimental groups. While scopolamine animals experienced more detrimental effects initially, they caught up with the shock group and finally became superior. This shift is interpreted in terms of building tolerance to scopolamine and increasing anxiety to shock as effects of differential treatments accumulated.
Assuntos
Eletrochoque , Reversão de Aprendizagem/efeitos dos fármacos , Escopolamina/farmacologia , Animais , Aprendizagem por Discriminação/efeitos dos fármacos , Masculino , Orientação/efeitos dos fármacos , Resolução de Problemas/efeitos dos fármacos , Ratos , Retenção Psicológica/efeitos dos fármacosRESUMO
An illustration that both the palm illusion and the moon's illusory size on the horizon are explained by the context which provides a contrast created by perceptual constancy.
Assuntos
Percepção de Forma , Ilusões , Ilusões Ópticas , Percepção de Tamanho , Fenômenos Astronômicos , Astronomia , Atenção , HumanosRESUMO
129 college students were individually requested to successively turn 2 of 3 upright triangles upside-down. Triangle consists of 3 rows of coins: 1 on top, 2 in the middle, and 3 at the bottom. Only 2 coins may be relocated. Triangle B has 4 rows with 4 coins at the bottom. Only 3 coins may be moved. Triangle C is arranged in 5 rows with 5 coins at the bottom. Only 5 coins are allowed to change places. Analysis shows (a) Problem A is the easiest, B in between, and C the hardest. (b) Overt manipulation is more efficient than a covert method. (c) Transfer in all cases is positive, the amount increasing with difficulty of the preceding problem. (d) From easy to difficult problems is more economical than the opposite sequence as measured by the total time required to solve both problems. The advantage is a little greater under the overt than the covert condition.
Assuntos
Atenção , Percepção de Forma , Orientação , Reconhecimento Visual de Modelos , Resolução de Problemas , HumanosRESUMO
A behavioral quantal theory of brain function is formulated on the basis of a newly discovered step-wise relationship invariably present among the findings of three experiments by Tsai, et al. on the effects of (1) cerebral decortication, (2) cranial x-radiation, as well as (3) insulin, metrazol, and electroconvulsive shocks upon white rats' adaptive behavior during their learning of successive habit reversals and one-trial reversal problems. Confirmatory results from earlier investigators who studied effects of various current strengths of ECS upon learning and retention of various maze habits are also cited in support of the behavioral quantal theory of brain function which is proposed here as a close-up, more refined alternative to Lashley's continuity theory of mass action.
Assuntos
Encéfalo/fisiologia , Teoria Quântica , Transmissão Sináptica , Animais , Comportamento Animal/fisiologia , Córtex Cerebral/fisiologia , RatosAssuntos
Atenção , Percepção de Forma , Ilusões , Ilusões Ópticas , Reconhecimento Visual de Modelos , HumanosAssuntos
Cegueira , Ilusões , Sinais (Psicologia) , Lateralidade Funcional , Humanos , Movimento , TatoAssuntos
Formação de Conceito , Percepção de Tamanho , Fatores Etários , Criança , Desenvolvimento Infantil , Pré-Escolar , Percepção de Cores , Humanos , LactenteRESUMO
Unpasteurized egg white was concentrated by ultrafiltration to about one half of its original volume. Twenty four batches, each started with 5,000 pounds of fresh egg white, were carried out in a 12-month period with a SANOVO Unit in an egg products plant. The optimum operating pressure was found to be about 415 psi. Higher pressure did not benefit the overall efficiency; on the contrary, it increased the chances of fouling and possibly compaction of the membrane and shortened the membrane life. As no refrigeration was provided in the system, egg white temperature rose linearly in all trials. The aerobic plate count of microorganisms was found to be doubled within 1-3 h when the ending temperature was above 20 C and over 10 h when the ending temperature was less than 16 C. The logarithm of permeation rate (R, lb./min) was linearly proportional to operating time (t, min) and the percent solids content of egg white (S). The solids content at a given time can be predicted by the equation: The estimated cost of concentrating egg white from 11.5 to 23% solid and at a volume of 10,000 lb. per day or 2,500,000 lb. per year, was $0.0295 per pound of concentrate. The accountable net savings for liquid egg white which would be shipped in tankers from the west coast to the midwest, and subsequently spray dried, was about $0.0117 per pound of concentrate and $0.0095 for frozen products. The return on capital investment would be approximately 35-40%.
RESUMO
Saponins isolated from alfalfa by ethanol extraction and acid hydrolysis were incorporated into protein-free purified diets at 0, .5, 1, 2, and 4% of dietary dry matter to investigate the effect of saponins on fermentation by mixed rumen bacteria maintained in continuous culture. Inoculum was obtained from a lactating dairy cow fed alfalfa hay and a 13% crude protein grain mixture with forage to grain ratios of 33:67, 67:33, or 100:0. Outflow of microbial protein was lower in fermenters fed purified diet containing 1% saponins. Accumulation of ammonia was observed in fermenters fed purified diets containing alfalfa saponins. Total volatile fatty acid production was reduced by addition of isolated alfalfa saponin fraction at .5, 1, 2, and 4% concentrations. Acetate to propionate ratios were reduced from 1.93 in control to 1.37 in fermenters with 1% saponins. Extent of change in fermentation was not proportional to the concentration of added saponins.