New method for determining a direction to an electromagnetic radiation source

The method for determining the direction of an electromagnetic radiation source without the interference of signals from two receivers is described.     

Stabilization of oil-in-water emulsions by enzyme catalyzed oxidative gelation of sugar beet pectin

Enzyme catalyzed oxidative cross-linking of feruloyl groups can promote gelation of sugar beet pectin (SBP). It is uncertain how the enzyme kinetics of this cross-linking reaction are affected in emulsion systems and whether the gelation affects emulsion stability. In this study, SBP (2.5% w/v) was mixed into an oil-in-water emulsion system (4.4% w/w oil, 0.22% w/w whey protein, pH 4.5). Two separate, identically composed, emulsion systems were prepared by different methods of preparation. The emulsions prepared separately and subsequently mixed with SBP (referred as Mix A) produced significantly larger average particle sizes than the emulsions in which the SBP was homogenized into the emulsion system during emulsion preparation (referred as Mix B). Mix B type emulsions were stable. Enzyme catalyzed oxidative gelation of SBP helped stabilize the emulsions in Mix A. The kinetics of the enzyme catalyzed oxidative gelation of SBP was evaluated by small angle oscillatory measurements for horseradish peroxidase (HRP) (EC 1.11.1.7) and laccase (EC 1.10.3.2) catalysis, respectively. HRP catalyzed gelation rates, determined from the slopes of the increase of elastic modulus (G′) with time, were higher (P < 0.05) than the corresponding laccase catalyzed rates, but the final G′ values were higher for laccase catalyzed gels, regardless of the presence of emulsions or type of emulsion preparation (Mix A or Mix B). For both enzymes, rates of gelation in Mix A were higher (P < 0.05) than in Mix B, and higher stress was needed to break the gels in Mix A than in Mix B at similar enzyme dosage levels. These differences may be related to a lower availability of the feruloyl groups for cross-linking when the SBP was homogenized into the emulsion system during preparation.     

Redundancy gains for visual search after complete commissurotomy.

Redundant-targets effects (RTE) for visual search were investigated in 2 commissurotomy patients (L.B., N.G.). L.B., who showed no evidence of visual interhemispheric transfer, exhibited a paradoxical enhancement of the redundancy gain in the bilateral compared with the within-hemifield redundant-targets conditions, whereas N.G., who showed evidence of interhemispheric transfer of visual information, exhibited no enhancement of the bilateral redundancy gain. When only uncrossed responses were considered, both bilateral and within-field RTE were evident only when attentional demands were high. Bilateral redundant targets led to stronger gains, some indicative of coactivation, in the slower response hand. The authors suggest that the enhancement of the bilateral RTE comes about by neural coactivation, which is especially pronounced when the slower hemisphere elicits the response. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Lead toxicosis in a captive bottlenose dolphin (Tursiops truncatus) consequent to ingestion of air gun pellets

Male rats of the Wistar strain were selected as good copulators (displaying at least 1 ejaculation in each of three consecutive tests for male sexual behavior) and sexually sluggish animals (displaying no ejaculations in each of three consecutive tests). The administration of low doses (1 and 2.5 mg/kg, i.p.) of kainic acid in sexually sluggish rats induced an enhancement of some parameters of copulatory behavior. In particular, significant reductions in latency to the first mount and intromission and increases in frequency of mounts and intromissions were observed. In contrast, the drug failed to exert any effect in good copulators. At the dose of 5 mg/kg (i.p.) kainic acid exerted an inhibitory effect on sexual behavior parameters both in good copulators and in sluggish rats. A persistent increase in latency to the first mount, intromission and ejaculation, and reduction in frequency of mounts, intromissions and ejaculation both in good copulators and in sluggish rats were observed 20 days after kainic acid treatment at the higher dose. No persistent effect of kainic acid 1 and 2.5 mg/kg was observed 20 days after treatment. These results suggest that kainic acid may affect in a dose-dependent manner several copulatory parameters of male sexual behavior repertoire. The bimodal effects could be explained considering a possible interaction of kainic acid with different neurotransmissions or receptor subtypes.     

Aneurysmatic dilatation of the duodenum and a nephrointestinal fistula in a case of abdominal lymphoma

A 73-year old woman presented with malaise, weight loss and urinary tract infection. Aneurysmatic dilatation of the duodenum and a nephrointestinal fistula were radiologically demonstrated. The two, very rare phenomena coincided in one patients and were due to abdominal lymphoma.     

Driver's decision process on termination of the green light

The paper describes the background and evaluates the effectiveness of a flashing green phase just before the amber leading to red phase in the traffic signal cycle. This type of signal sequence, practiced in Israel and a few other countries, was thought to provide drivers with useful information which should lead to better stop or go decisions. However, accident analysis studies have shown an increase in collisions following the introduction of a flashing green. A laboratory simulation study designed to explain the accident findings was conducted. It was found that the flashing green elicited from the drivers an earlier decision response and a higher number of inappropriate stopping decisions, particularly close to the intersection. The pattern of stopping and crossing decisions in the flashing green program suggests more friction between stopping and nonstopping vehicles and, therefore, a higher likelihood of front-rear collisions compared to a regular program.     

Preventing drowsiness accidents by an alertness maintenance device

The reported experiment investigated in an advanced driving simulator whether drivers' alertness can be maintained in drowsiness-inducing conditions by a special game-like system, a 'gamebox'. Drowsiness was assessed by self-rating and eye-closures. Mental effort was assessed by a subjective workload rating scale and by a physiological measure (the 0.1 Hz component of heart rate). Driving quality and safety were assessed by steering movements, time-to-line crossings, and by the occurrence of safety-related driving errors--solid line crossings, driving off-road incidents and accidents. When driving with the gamebox, drivers reported a lower degree of drowsiness and fewer instances of sleep episodes as compared to a control condition. Driving with the device resulted in fewer incidents and accidents, and these occurred later in the session. The quality of vehicle control deteriorated progressively over the course of the session, but less so in the gamebox condition. Hence, the results corroborate the notion that mental activity counteracts drowsiness in prolonged driving.     

Interhemispheric relations in processing hierarchical patterns: Evidence from normal and commissurotomized subjects.

On the basis of a review of neuropsychological evidence for several component processes of responding to global and local levels of hierarchically structured patterns, L. C. Robertson and M. R. Lamb (see record 1991-24938-001) hypothesized that interhemispheric communication between posterior cortexes would disrupt the typically interfering effects of global patterns on local response. These studies confirmed this hypothesis in 3 commissurotomized Ss. The normal interaction between visual field presentation and global or local level was present in normal Ss and all 3 patients, but global interference was absent or even reversed in patients. These data are discussed as they relate to the function of the corpus callosum and functional hemisphere asymmetries in responding to global and local levels of hierarchical forms. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Modeling controlled nutrient release from polymer coated fertilizers: diffusion release from single granules

A comprehensive model describing the complex and "non-Fickian" (mathematically nonlinear) nature of the release from single granules of membrane coated, controlled release fertilizers (CRFs) is proposed consisting of three stages: i. a lag period during which water penetrates the coating of the granule dissolving part of the solid fertilizer in it ii. a period of linear release during which water penetration into and release out occur concomitantly while the total volume of the granules remains practically constant; and iii. a period of "decaying release", starting as the concentration inside the granule starts to decrease. A mathematical model was developed based on vapor and nutrient diffusion equations. The model predicts the release stages in terms of measurable geometrical and chemophysical parameters such as the following: the product of granule radius and coating thickness, water and solute permeability, saturation concentration of the fertilizer, and its density. The model successfully predicts the complex and "sigmoidal" pattern of release that is essential for matching plant temporal demand to ensure high agronomic and environmental effectiveness. It also lends itself to more complex statistical formulations which account for the large variability within large populations of coated CRFs and can serve for further improving CRF production and performance.