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Mental health research funding priorities in high-income countries must balance longer-term investment in identifying neurobiological mechanisms of disease with shorter-term funding of novel prevention and treatment strategies to alleviate the current burden of mental illness. Prioritising one area of science over others risks reduced returns on the entire scientific portfolio.
The understanding of embryology provides a foundation for the mastery of anatomy. In the treatment of men with infertility, it is only appropriate that one deals with the basics of fetal development of the male reproductive tract. This chapter reviews the germ layers from which all tissues organize themselves and develop, and also reviews the ductal system and its critical role in reproduction. The cloaca, as incorporated yolk sac, is an endoderm-lined cavity, anchored at the caudal end by the cloacal membrane. The mesonephric ducts, which are mesodermal structures, are connected to the urogenital sinus bilaterally. The common excretory ducts eventually move into the prostatic part of the urethra and become known as the verumontanum. Testosterone stimulates numerous changes in the existing ductal system. In the presence of testosterone, the phallus lengthens and enlarges to form the penis.
Alternative models of residential mobility have been proposed to explain the development and spread of Tiwanaku influence across the south central Andes. Within the Osmore drainage, the rich Moquegua Valley has been hypothesized as the site of a significant colonization event (or events) whereby both the natural and human landscape was transformed and integrated into the expansive Tiwanaku state. In this research, the impact of altiplano colonization is inferred from temporal and spatial patterns of genetic variation within and among native groups. Mitochondrial DNA haplogroup frequencies are used as the measure of genetic variation. The haplogroup data are determined for Moquegua Valley archaeological samples (Chen Chen site; A.D. 785-1000) and are compared to published data from 58 other ancient and contemporary native groups. The results support temporal and spatial genetic continuity in the south central Andes for the last 1,000 years. Contemporary Aymara speaking groups are exceptions to this pattern, perhaps because of recent population decline. While the altiplano colonization hypothesis is not rejected, moderate gene flow and relatively large population sizes likely characterized much of south central Andean prehistory regardless of the contribution from Tiwanaku colonization events.
The presence of intracellular bacteria in the dinoflagellate Gyrodinium instriatum Freudenthal & Lee has previously been described but the bacterial flora associated with this species has not been characterized. In this study, new results of transmission electron microscopy (TEM) and in situ hybridization using several bacterial group-specific oligonucleotide probes are presented. The long-term association of endocytoplasmic and endonuclear bacteria with G. instriatum has been confirmed. All endonuclear and most of the endocytoplasmic bacteria labelled were identified as belonging to the betaproteobacteria. Large clusters of Cytophaga-Flavobacterium-Bacteroides (CFB) were labelled and observed in the cytoplasm of the dinoflagellate cells, but were absent from the nucleus. Gammaproteobacteria were only observed outside the dinoflagellates. No alphaproteobacteria were detected either free-living or intracellular. Empirical observation of intracellular CFB reflected a degradation process of moribund dinoflagellate cells, whereas the systematic colonization of dinoflagellate nucleoplasm by betaproteobacteria suggested a true symbiotic relationship. Natural colonization may have occurred, perpetuated by vertical transmission of intracellular bacteria to the dinoflagellate daughter cells, via a pool of bacteria sequestered within the nucleus. Dividing bacteria were observed in the nucleus and equilibrium may be maintained by release of endonuclear bacteria to the cytoplasm through nuclear envelope constrictions.
Initial results for the continuous microwave processing of wide webs using a new microwave applicator are presented. The results show that acceptable uniformity can be obtained using this system and that with the appropriate controls, a very tight process window can be maintained to produce preimpregnated glass cloth (prepreg) for use in circuit board manufacture.
As applications for polymeric materials continue to expand, cost-effective and environmentally responsible processing methods become vitally important. It is also becoming increasingly apparent that the success of some new materials is tightly coupled to their processing technologies because the development of their properties depends directly on the processing. In thermoplastic-toughened thermoset resins, for example, morphology development during processing is critical to the mechanical performance of the final material.
Microwave processing has enjoyed growing interest primarily because of the potential of uniformly heating relatively large volumes of materials very rapidly; this overcomes limitations due to the poor thermal conductivity of polymeric materials. Microwave radiation has a very large penetration depth in polymeric materials, and absorption follows a simple Beer-Lambert Law. Hence, depending on the material, very uniform heating profiles throughout the thickness of a material can be obtained up to 0.5 m. This bulk absorption of energy allows for substantially higher heating rates than can be obtained using conventional or infrared methods and for the retention of an acceptable heating profile. Other advantages of this technology include (1) more efficient heating and thus efficient use of energy (only the part is heated, not the walls and surrounding air); (2) shorter processing time for batch operations; (3) shorter process lines for continuous operations; (4) environmental superiority; (5) production of properties or morphologies not attainable using other processing techniques; and (6) the possibility of selective heating—the selective absorption of energy by one phase or part of a material—leading to a custom temperature profile within a part.