Modelling of Propulsion Shaft Line and Basic Procedure of Shafting Alignment Calculation

The main propulsion shafting is exposed to various operating conditions throughout the entire lifetime of a modern ship. The necessary condition for the shafting to withstand and survive all possible situations is its proper dimensioning and manufacture, as well as its assembly and testing onboard. Its alignment is of utmost importance during the assembly process itself. The aim of this paper is to present the shafting alignment calculation procedure in order to help the designer to understand the whole alignment process. Calculation presumptions, modelling of shafting parts, material properties and loading are given in detail. The advantages of the transfer matrix methods over the fi nite element methods in this particular case have been described. The important part is to establish the designed shafting elastic line onboard the ship, during the outfi tting in the shipyard. It is proposed in the conclusion that the presented matter be included into a future edition of the CRS Technical Rules

An Approach to Calculation of Marine Machinery Flexible Seating

Brodski porivni i pomoćni strojevi temelje se kruto (na metalnim, ili podlogama od smole) ili elastično (na elastičnim podlogama s gumenim dijelovima). Osnovna je svrha elastičnog temeljenja smanjiti nepovoljan utjecaj vibracija i neposredan prijenos buke izazvane radom strojeva na brodsku konstrukciju. Elastično se temeljenje zbog toga često rabi na putničkim brodovima. Cilj je u ovom radu prikazati pojednostavnjeni postupak proračuna elastičnog temeljenja brodskih strojeva kako bi se olakšao rad projektantima brodskih pogonskih i pomoćnih sustava. Pojednostavnjeni se proračun u osnovi svodi na određivanje statičkih sila u elastičnim podlogama, a zatim i prirodnih frekvencija sustava sa šest stupnjeva slobode, iz kojih se dobivaju kritične brzine vrtnje. Proračun je prikazan matrično (analogno metodi konačnih elemenata za deformabilne sustave) s pojedinostima potrebnim projektantu za samostalan rad. Načelno je prikazana i metodologija proračuna prisilnih prigušenih vibracija, to jest uzbudnih sila i posljedičnih dinamičkih odziva sustava. Doprinos je rada u matrično sažetoj metodologiji proračuna, te u prijedlogu izbjegavanja izračuna uzbudnih sila. Naime, u izvjesnim uvjetima, dostatno je poznavati samo ritam (frekvenciju) uzbude izazvanu radom motora s unutarnjim izgaranjem i brodskoga vijka, a ne i njezinu veličinu ili fazu, te u Campbellovu dijagramu usporediti tu frekvenciju s izračunatim prirodnim frekvencijama sustava. Tako se odlučuje je li složeniji pristup potreban ili ne. Prikazan je primjer rezultata proračuna za porivni sustav više putničkih brodova izgrađenih u domaćem brodogradilištu, uz usporedbu s rezultatima mjerenja iz literature na prvom brodu. Zaključuje se da proračun elastičnog temeljenja ne treba izbjegavati u praksi, što je često, nego primjenom predloženoga jednostavnog postupka provesti potrebne statičke i dinamičke analize. Tako se dovoljno rano u projektnoj fazi mogu predvidjeti i riješiti poteškoće koje je poslije bilo teško otklanjati.Marine propulsion and auxiliary machinery are seated on stiff seating (metal supports or resin chocks) or flexible seating (elastic supports with rubber parts). The basic purpose of flexible seating is to reduce detrimental influence of vibrations and direct transfer of noise to the ship structure. Consequentially, flexible seating is usually implemented in passenger ships. The aim of this paper is to present a simplified procedure for calculation of flexible seating for marine machinery, in order to ease the work of designers of marine propulsion and auxiliary machinery. The simplified calculation basically contains of evaluation of static forces in the flexible supports, as well as the natural frequencies for the six degree-of-freedom system, from which critical rotational speeds can be determined. The calculation is presented in matrix form (similar to the conventional FEM calculations of linear elastic systems) with all the necessary details enabling a designer’s autonomous work. Generally, the methodology of calculation of system dynamic response to forced damped vibrations is also presented. The contribution of the paper is in the calculation methodology presented in matrix form, as well as in the proposal to avoid evaluation of excitation forces. Under certain conditions it is enough to know only the frequency of the excitations, caused by internal combustion engine cylinders and propeller in operation, but not their magnitude or phase, as well as to compare that frequency in Campbell diagram with the calculated natural frequencies to make the decision about the necessity of more complex approach. An example of calculation results for the flexibly mounted propulsion system of a series of newbuildings, built in a domestic shipyard, has been presented, together with the comparison with the measurement results from the literature on the first ship. It is concluded that the calculation of flexible seating should not be avoided in practice, what is a common situation. Contrary, by implementing the proposed simplified calculation procedure the necessary static and dynamic analyses should be performed. This is the way to avoid difficulties during the design phase early enough, which are not easy to deal with later on

Transcriptional co-regulation of neuronal migration and laminar identity in the neocortex

The cerebral neocortex is segregated into six horizontal layers, each containing unique populations of molecularly and functionally distinct excitatory projection (pyramidal) neurons and inhibitory interneurons. Development of the neocortex requires the orchestrated execution of a series of crucial processes, including the migration of young neurons into appropriate positions within the nascent neocortex, and the acquisition of layer-specific neuronal identities and axonal projections. Here, we discuss emerging evidence supporting the notion that the migration and final laminar positioning of cortical neurons are also co-regulated by cell type- and layer-specific transcription factors that play concomitant roles in determining the molecular identity and axonal connectivity of these neurons. These transcriptional programs thus provide direct links between the mechanisms controlling the laminar position and identity of cortical neurons

Microarray analysis of microRNA expression in the developing mammalian brain

BACKGROUND: MicroRNAs are a large new class of tiny regulatory RNAs found in nematodes, plants, insects and mammals. MicroRNAs are thought to act as post-transcriptional modulators of gene expression. In invertebrates microRNAs have been implicated as regulators of developmental timing, neuronal differentiation, cell proliferation, programmed cell death and fat metabolism. Little is known about the roles of microRNAs in mammals. RESULTS: We isolated 18-26 nucleotide RNAs from developing rat and monkey brains. From the sequences of these RNAs and the sequences of the rat and human genomes we determined which of these small RNAs are likely to have derived from stem-loop precursors typical of microRNAs. Next, we developed a microarray technology suitable for detecting microRNAs and printed a microRNA microarray representing 138 mammalian microRNAs corresponding to the sequences of the microRNAs we cloned as well as to other known microRNAs. We used this microarray to determine the profile of microRNAs expressed in the developing mouse brain. We observed a temporal wave of expression of microRNAs, suggesting that microRNAs play important roles in the development of the mammalian brain. CONCLUSION: We describe a microarray technology that can be used to analyze the expression of microRNAs and of other small RNAs. MicroRNA microarrays offer a new tool that should facilitate studies of the biological roles of microRNAs. We used this method to determine the microRNA expression profile during mouse brain development and observed a temporal wave of gene expression of sequential classes of microRNAs

Temporal Specification and Bilaterality of Human Neocortical Topographic Gene Expression

SummaryTranscriptional events involved in the development of human cerebral neocortex are poorly understood. Here, we analyzed the temporal dynamics and laterality of gene expression in human and macaque monkey neocortex. We found that interareal differences exhibit a temporal hourglass pattern, dividing the human neocortical development into three major phases. The first phase, corresponding to prenatal development, is characterized by the highest number of differential expressed genes among areas and gradient-like expression patterns, including those that are different between human and macaque. The second, preadolescent phase, is characterized by lesser interareal expression differences and by an increased synchronization of areal transcriptomes. During the third phase, from adolescence onward, differential expression among areas increases again driven predominantly by a subset of areas, without obvious gradient-like patterns. Analyses of left-right gene expression revealed population-level global symmetry throughout the fetal and postnatal time span. Thus, human neocortical topographic gene expression is temporally specified and globally symmetric

Mutations in LAMB1 Cause Cobblestone Brain Malformation without Muscular or Ocular Abnormalities

Cobblestone brain malformation (COB) is a neuronal migration disorder characterized by protrusions of neurons beyond the first cortical layer at the pial surface of the brain. It is usually seen in association with dystroglycanopathy types of congenital muscular dystrophies (CMDs) and ocular abnormalities termed muscle-eye-brain disease. Here we report homozygous deleterious mutations in LAMB1, encoding laminin subunit beta-1, in two families with autosomal-recessive COB. Affected individuals displayed a constellation of brain malformations including cortical gyral and white-matter signal abnormalities, severe cerebellar dysplasia, brainstem hypoplasia, and occipital encephalocele, but they had less apparent ocular or muscular abnormalities than are typically observed in COB. LAMB1 is localized to the pial basement membrane, suggesting that defective connection between radial glial cells and the pial surface mediated by LAMB1 leads to this malformation

Rare deleterious mutations of the gene EFR3A in autism spectrum disorders

Background: Whole-exome sequencing studies in autism spectrum disorder (ASD) have identified de novo mutations in novel candidate genes, including the synaptic gene Eighty-five Requiring 3A (EFR3A). EFR3A is a critical component of a protein complex required for the synthesis of the phosphoinositide PtdIns4P, which has a variety of functions at the neural synapse. We hypothesized that deleterious mutations in EFR3A would be significantly associated with ASD. Methods: We conducted a large case/control association study by deep resequencing and analysis of whole-exome data for coding and splice site variants in EFR3A. We determined the potential impact of these variants on protein structure and function by a variety of conservation measures and analysis of the Saccharomyces cerevisiae Efr3 crystal structure. We also analyzed the expression pattern of EFR3A in human brain tissue. Results: Rare nonsynonymous mutations in EFR3A were more common among cases (16 / 2,196 = 0.73%) than matched controls (12 / 3,389 = 0.35%) and were statistically more common at conserved nucleotides based on an experiment-wide significance threshold (P = 0.0077, permutation test). Crystal structure analysis revealed that mutations likely to be deleterious were also statistically more common in cases than controls (P = 0.017, Fisher exact test). Furthermore, EFR3A is expressed in cortical neurons, including pyramidal neurons, during human fetal brain development in a pattern consistent with ASD-related genes, and it is strongly co-expressed (P < 2.2 × 10−16, Wilcoxon test) with a module of genes significantly associated with ASD. Conclusions: Rare deleterious mutations in EFR3A were found to be associated with ASD using an experiment-wide significance threshold. Synaptic phosphoinositide metabolism has been strongly implicated in syndromic forms of ASD. These data for EFR3A strengthen the evidence for the involvement of this pathway in idiopathic autism

オンガクゲキ ヒョウゲン カテイ ニオケル ガイテキ ナイテキ ケイショウ ノ イミ : オンガクゲキ キャクホン ツタカズラ コマチデン オ ジレイ トシテ

The purpose of this paper is to consider the meaning of external, internal images in the process of expression on music drama. The major results of this consideration can be summarized as follows: The external image is the "form" of reality, embodiment, that is to say, something visible and audible. On the other hand, the internal image is the simbolic form of idea, imagination, visions, enviromental factor, affect (i. e. substance of consciousness, etc.), that is to say, samething invisible. And the expression in the Music Drama is itself the mental act of representing subject subsisted in emotion and reality from expression, such as singing, acting and the theatrical line, etc..国立情報学研究所『研究紀要公開支援事業』により電子化