Ontogenesis of peripheral electromagnetic receptors in hornets

This article traces the ontogenesis of peripheral electromagnetic receptors (PER) in the cuticle of the Oriental hornet (Vespa orientalis). In the abdominal cuticle of adult hornets, the PERs are densely distributed throughout, but there are even more than 30 at the margins of the segments. These organelles develop as a network in the hornet cuticle immediately upon its completion. Briefly, from each basic cell of a PER grows a bulge towards the exterior, that is, towards the illuminated region of the cuticle. This bulge develops rapidly and as it grows it starts to push out and lift up the various layers of the cuticle, the while pressing them together. By a spiraling movement, the bulge insinuates itself between the layers, whereupon it dissolves and punctures its way through all the layers of the hypocuticle, via the endocuticle up to the exocuticle. The only cuticular layer that remains intact is the epicuticle, but even that undergoes change, assuming the shape of a smooth surface with a depression at its center. The indented part in the epicuticle is circular, approximately 2.5 microm in diameter and enables the entry of radiation (illumination) from the outside into the PER, which is located half-way down the cuticle, with the distance from the exterior to the base of the PER being approximately 25 microm. The numerous lamellae of the cuticle run parallel to one another, but in the region of the bulge they are either perpendicular or directed upwards. This ontogeny of the PERs lends the cuticle a sandwich-like shape, being radically perforated by the PERs bulges, yet covered at the top by the epicuticle and at the bottom by basal cells. The PERs also extend shoots into the cuticular layer and these further perforate the cuticle but also interlink the various PERs. From all the above, it is clear that the cuticle forms first and only subsequently does the network of PERs develop and interpenetrate its various layers.     

Continuous/discrete simulation of controlled atmosphere (CA) cool storage systems: model development and validation using pilot plant CA cool storage

Simulation of dynamic processes in controlled atmosphere (CA) cool room storage systems has been developed. The model consists of three interacting sub-models for the prediction of the transient behavior of the processes in the three units, namely, the cool room, the refrigeration system and the gas-handling unit. Several modules representing each of the components in these units were developed based on energy and mass balances. The modules were then arranged to form the sub-models, which were interconnected, in turn, into the global CA cool storage system model. The modules were implemented in an object-oriented computational environment, (EcosimPro) which can handle both continuous and discrete events. The model was validated using experimental data from a pilot plant CA cool storage facility. Model predictions of the most important discrete and continuous processes were found to agree to the experimental data with a maximum difference less than the observed spatial variability or at best with the accuracy level as set by the measurement instruments. As product respiration and quality models are incorporated, it is possible to use the model for optimization of plant performance with respect to the final quality of the stored product. Moreover, the handling of discrete/continuous events enables the implementation of practical operational procedures and to investigate their implication directly on the product quality and plant performance/design.     

Assessment and evaluation of the radiological situation in the late phase of a nuclear accident

An overview of existing approaches on assessing and evaluating the radiological situation in the late phase of a nuclear accident is given in this paper. Special attention is paid to the weak points of existing approaches and to problems to be solved in the future. Assessment of the radiological situation can be based on both monitoring data and model predictions. Approaches have been developed for many years in both categories and have meanwhile reached some kind of maturity and also operational applicability. Nevertheless, some areas exist where significant improvements could be achieved in the near future, e.g. by combining monitoring data and model predictions, by improving the modelling of urban areas or by improving existing radioecological models.     

Flows in micro fluidic networks: From theory to experiment

When complex flow structures are designed, such as in DNA computing, it is essential to be able to predict the flow pattern of the solutions in the fluidic network. A model based on the resistance of the channels and flow velocities of the inlets can eliminated re-iterative design steps. We have constructed a symbolic model using Mathematica ® to determine the desired flow pattern based on the equations of Ohm and Kirchoff. The values from this simulation were used in a flow simulation program and then tested in a microflow network. Results show that the simulation and calculation match very well, while the experiments in the fluidic network show a flow pattern as predicted by the model.     

Preferential utilization of ketone bodies for the synthesis of myelin cholesterol in vivo

1. The distribution of radioactivity among lipid classes of myelin and other subcellular brain fractions of young rats (18-21 days) was determined after in vivo injection of (3-(14)C-labelled ketone bodies, [U-(14)C] glucose or [2-(14)C] glucose. 2. The incorporation ratios (sterol/fatty acids) were 0.67, 1.48, 0.25, 0.62 and 0.54 for whole brain, myelin, mitochondria, microsomes and synaptosomes, respectively, with (3-(14)C)-labelled ketone bodies as substrate and 0.37, 0.89, 0.19, 0.34 and 0.29 with [U-(14)C] glucose as substrate. These data show that, both in whole brain and in subcellular brain fractions, acetyl groups derived from ketone bodies are used for sterol synthesis to a large extent than acetyl groups originating from glucose. 3. The specific radioactivity of cholesterol is much higher in myelin than in whole brain or in the other brain fractions, particularly after administration of labelled ketone bodies as substrate. 4. The incorporation patterns of acetoacetate and D-3-hydroxybutyrate were very similar, indicating that both ketone bodies contribute acetyl groups for lipid synthesis via the same metabolic route. 5. Our data suggest that a direct metabolic path from ketone bodies towards cholesterol exists - possibly via acetoacetyl-CoA formation in the cytosol of brain cells - and that this process is most active in oligodendrocytes.     

Rumen microbial growth rates and yields: effect of amino acids and protein.

Effects of amino acids upon microbial growth, optimum ratio of nonprotein to amino acid nitrogen for microbial growth, and incorporation of amino acids into microbial cells were determined with washed cell suspension in vitro as were rumen microbial cells. Rumen microbial dry matter, nitrogen, ribonucleic acid, deoxyribonucleic acid, and substrate disappearance was greatest when a mixture of 18 amino acids was substituted for urea. Substitutions of mixtures of 10 essential amino acids, 8 nonessential amino acids, and sulfur containing amino acids and glutamate also stimulated microbial growth. Acid hydrolyzed casein markedly improved microbial growth. Branched amino acid addition did not affect growth. The optimum ratio of nonprotein to amino acid nitrogen for microbial growth was 75% urea nitrogen and 25% amino acid nitrogen. With this amount of amino acids, an average of 53% of added amino acid was incorporated into microbial cells, 14% was fermented to carbon dioxide and volatile fatty acids, and 33% remained in the supernatant. Both 100% urea and 100% amino acid in growth media were unfavorable for maximal microbial growth. With all carbohydrate substrates, 100% urea nitrogen supported the growth of 9 mg bacterial dry matter per 100 mg of substrate. Substitutions of amino acids for urea increased yields to over 20 mg/100 mg. Microbial growth yields in incubations under carbon dioxide were less than when flasks were flushed with nitrogen. However, yield of bacterial dry matter per unit of substrate was less under nitrogen than under carbon dioxide.     

Interlaminar stress analysis for laminated plates containing a curvilinear hole

This study presents a variational-perturbation approach for the three-dimensional stress analysis around a curvilinear cutout in composite laminates. The solution is based on a composite expansion and assumed stress finite element methods. Stress field solutions for angleply and cross-ply laminates containing an elliptical hole have been presented. The effects of the ellipse aspect ratio and the fiber orientation on the interlaminar shear stress magnitude have been investigated. A failure criterion based on the interlaminar distortional energy function has been suggested. According to this criterion, it was found that, for angle-ply laminates containing an elliptical hole, a delamination failure initiation occurs at a point along the perpendicular to the direction of loading.     

Classifications and salaries of psychologists in state mental hospital systems.

Afour-and-a-half page table summarizes job classifications and salaries of psychologists in the state mental hospital systems of 42 states. The data were acquired by means of a 3-page questionnaire directed to the various mental hospital authorities. "Although functions within state systems vary, indications are that the psychologist continues to find his role in this facet of public service administratively defined as one in which psychodiagnostic skills are primary." Noteworthy, however, "was the extent to which active involvement of the psychologist was also anticipated in the treatment process, research, and teaching of other institutional personnel." 2 states "specified that candidates for their top level positions must possess an ABEPP diploma, and two more expressed the desirability for such… . Twenty-five… states evidenced some enhancement of salary in the form of maintenance or residential perquisites." Major headings in the table refer to: state, job title, educational requirement, professional experience, annual salary, and residential perquisites. (PsycINFO Database Record (c) 2010 APA, all rights reserved)