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Genome-wide association studies (GWASs) have identified several susceptibility loci for bipolar disorder (BD) and shown that the genetic architecture of BD can be explained by polygenicity, with numerous variants contributing to BD. In the present GWAS (Phase I/II), which included 2964 BD and 61 887 control subjects from the Japanese population, we detected a novel susceptibility locus at 11q12.2 (rs28456, P=6.4 × 10−9), a region known to contain regulatory genes for plasma lipid levels (FADS1/2/3). A subsequent meta-analysis of Phase I/II and the Psychiatric GWAS Consortium for BD (PGC-BD) identified another novel BD gene, NFIX (Pbest=5.8 × 10−10), and supported three regions previously implicated in BD susceptibility: MAD1L1 (Pbest=1.9 × 10−9), TRANK1 (Pbest=2.1 × 10−9) and ODZ4 (Pbest=3.3 × 10−9). Polygenicity of BD within Japanese and trans-European-Japanese populations was assessed with risk profile score analysis. We detected higher scores in BD cases both within (Phase I/II) and across populations (Phase I/II and PGC-BD). These were defined by (1) Phase II as discovery and Phase I as target, or vice versa (for ‘within Japanese comparisons’, Pbest~10−29, R2~2%), and (2) European PGC-BD as discovery and Japanese BD (Phase I/II) as target (for ‘trans-European-Japanese comparison,’ Pbest~10−13, R2~0.27%). This ‘trans population’ effect was supported by estimation of the genetic correlation using the effect size based on each population (liability estimates~0.7). These results indicate that (1) two novel and three previously implicated loci are significantly associated with BD and that (2) BD ‘risk’ effect are shared between Japanese and European populations.

Recent schizophrenia (SCZ) studies have reported an increased burden of de novocopy number variants (CNVs) and identified specific high-risk CNVs, although with variable phenotype expressivity. However, the pathogenesis of SCZ has not been fully elucidated. Using array comparative genomic hybridization, we performed a high-resolution genome-wide CNV analysis on a mainly (92%) Japanese population (1699 SCZ cases and 824 controls) and identified 7066 rare CNVs, 70.0% of which were small (<100 kb). Clinically significant CNVs were significantly more frequent in cases than in controls (odds ratio=3.04, P=9.3 × 10−9, 9.0% of cases). We confirmed a significant association of X-chromosome aneuploidies with SCZ and identified 11 de novoCNVs (e.g., MBD5deletion) in cases. In patients with clinically significant CNVs, 41.7% had a history of congenital/developmental phenotypes, and the rate of treatment resistance was significantly higher (odds ratio=2.79, P=0.0036). We found more severe clinical manifestations in patients with two clinically significant CNVs. Gene set analysis replicated previous findings (e.g., synapse, calcium signaling) and identified novel biological pathways including oxidative stress response, genomic integrity, kinase and small GTPase signaling. Furthermore, involvement of multiple SCZ candidate genes and biological pathways in the pathogenesis of SCZ was suggested in established SCZ-associated CNV loci. Our study shows the high genetic heterogeneity of SCZ and its clinical features and raises the possibility that genomic instability is involved in its pathogenesis, which may be related to the increased burden of de novoCNVs and variable expressivity of CNVs.

In heavy ion beam (HIB) inertial confinement fusion (ICF), key issues include beam illumination non-uniformity. In this study we simulate the HIB interaction with a direct-driven target. The main purposes of this study are to clarify the multi-HIB energy deposition non-uniformity onto a direct-driven target and to calculate the target hydrodynamics in HIF. The calculation results demonstrate that we can realize a rather low non-uniform energy deposition, for example, less than 2.0% even for a 32-HIBs irradiation system.

Beam dynamics and emittance growth are investigated by using particle-in-cell simulations during a final beam bunching for a driver system of inertial fusion driven by intense heavy ion beams. Space-charge-dominated beams are transported by a transverse confinement lattice with longitudinal compression, and the emittance increases along the longitudinal beam bunching. Dipole oscillations are excited due to the initial displacement of the beam center. The displacement causes the additional emittance growth during the final beam bunching.

In heavy ion beam (HIB) inertial confinement fusion (ICF), key issues include beam illumination non-uniformity. In this study we simulate the HIB interaction with a direct-driven target. The main purposes of this study are to clarify the multi-HIB energy deposition non-uniformity onto a direct-driven target and to calculate the target hydrodynamics in HIF. The calculation results demonstrate that we can realize a rather low non-uniform energy deposition, for example, less than 2.0% even for a 32-HIBs irradiation system.

Key issues of heavy-ion beam (HIB) inertial confinement fusion (ICF) include an efficient beam transport, beam focus, uniform fuel pellet implosion, etc. The HIB final transport and a direct-drive fuel pellet implosion by computer simulations in HIB ICF are examined. To realize a fine focus on a fuel pellet, space charge neutralization of incident-focusing HIBs may be required at HIB final transport. First, an insulator annular tube guide is proposed at the final portion of the transport, through which an HIB is transported. The physical mechanism of HIB charge neutralization based on an insulator guide is as follows: The local electric field created by HIB induces local discharges, and a plasma is produced on the insulator inner surface. Then electrons are extracted from the plasma by HIB net space charge. The emitted electrons neutralize the beam space charge and move together with the HIB. After the final transport, the HIBs enter a reactor gas and illuminate a fuel pellet. Direct-drive DT pellet implosion were also simulated. The simulation results present a density valley formation by a Pb HIB deposition in a fuel pellet energy absorber layer and a radiation-smoothing effect along the density valley. The density valley provides radiation confinement, and beam nonuniformity can be smoothed along the valley.

We first pay attention to the inflight charge state distribution in a Pb ion beam propagating in a reactor-sized chamber delimited by metallic walls. We thus compare Livermore (code BIC) and Orsay (code BPIC) distributions in the presence of a residual Flibe gas pressure. Next, we replace the electron plasma due to Flibe ionization by a gliding plasma produced by the polarization of the incoming ion beam on insulating walls. Corresponding electrons, when attracted by the beam, are demonstrated to yield a very efficient current neutralization.

Oligothiophene thin film transistors have recently been shown to respond to organic vapors, suggesting possible applicability in the field of olfactory sensor arrays. Here, we present a study of the correlation between the morphological structure of the active semiconductor thin film and the response to the vapor. The study was carried out by combining the measurement of the transient source−drain current of the transistor under vapor flow with the morphological characterization of the organic thin films by transmission electron microscopy.

We present the first observation of intersubband transition (ISBT) from the ground state (e1) to the third subband (e3) in GaN/AlGaN quantum wells (QWs). A clear peak of the ISBT e1–e3 was observed in GaN/Al0.56Ga0.44N QWs. This demonstrates that a strong built-in field due to the piezoelectric and spontaneous polarization effects exists in the structure. The polarization field results in a symmetry breaking of a QW, and thus ISBT e1–e3, which in a symmetrical square well is normally forbidden by parity. The band-to-band photoluminescence emission at energies below the GaN band gap also shows the existence of a polarization field.

We present the first observation of intersubband transition (ISBT) from the ground state (e1) to the third subband (e3) in GaN/AlGaN quantum wells (QWs). A clear peak of the ISBT e1–e3 was observed in GaN/Al0.56Ga0.44N QWs. This demonstrates that a strong built-in field due to the piezoelectric and spontaneous polarization effects exists in the structure. The polarization field results in a symmetry breaking of a QW, and thus ISBT e1–e3, which in a symmetrical square well is normally forbidden by parity. The band-to-band photoluminescence emission at energies below the GaN band gap also shows the existence of a polarization field.

We present the first observation of intersubband transition (ISBT) from the ground state (e1) to the third subband (e3) in GaN/AlGaN quantum wells (QWs). A clear peak of the ISBT e1–e3 was observed in GaN/Al0.56Ga0.44N QWs. This demonstrates that a strong built-in field due to the piezoelectric and spontaneous polarization effects exists in the structure. The polarization field results in a symmetry breaking of a QW, and thus ISBT e1–e3, which in a symmetrical square well is normally forbidden by parity. The band-to-band photoluminescence emission at energies below the GaN band gap also shows the existence of a polarization field.

We present the first observation of intersubband transition (ISBT) from the ground state (e1) to the third subband (e3) in GaN/AlGaN quantum wells (QWs). A clear peak of the ISBT e1–e3 was observed in GaN/Al0.56Ga0.44N QWs. This demonstrates that a strong built-in field due to the piezoelectric and spontaneous polarization effects exists in the structure. The polarization field results in a symmetry breaking of a QW, and thus ISBT e1–e3, which in a symmetrical square well is normally forbidden by parity. The band-to-band photoluminescence emission at energies below the GaN band gap also shows the existence of a polarization field.

We have successfully integrated microfluid flow channels, defined by surface energy differences, with thin-film organic field-effect transistors. The device performance is stable for specific semiconductors with water flowing over the channel region and the contacts protected by hydrophobic surface films, indicating that organic semiconductors are not necessarily degraded by water even when carrying current. In addition, a substantial response from dilute organic solutes, as low as 1 ppm in an aqueous environment, can be observed, with some degree of semiconductor−solute specificity.

Our recent progress in growth and optical properties of GaN-based quantum dot (QD) structures is reviewed. After discussing the impact of GaN-based QDs on threshold current characteristics, we have shown InGaN self-assembled QDs on a GaN epitaxial layer with average diameter as small as 8.4 nm and strong photoluminescence emission from the QDs at room temperature. Furthermore, light emission from individual QDs with sharp luminescence line was detected by single dot spectroscopy. Using these growth results, we fabricated a laser structure with InGaN QDs embedded in the active layer. A clear threshold was observed in the dependence of the emission intensity on the excitation energy at room temperature under optical excitation. Finally, growth of InGaN QDs grown by selective growth is also demonstrated.

Cysteine-scanning mutants as to putative transmembrane segments 4 and 5 and the flanking regions of Tn10-encoded metal-tetracycline/H(+) antiporter (TetA(B)) were constructed. All mutants were normally expressed. Among the 57 mutants (L99C to I155C), nine conserved arginine-, aspartate-, and glycine-replaced ones exhibited greatly reduced tetracycline resistance and almost no transport activity, and five conserved glycine- and proline-replaced mutants exhibited greatly reduced tetracycline transport activity in inverted membrane vesicles despite their high or moderate drug resistance. All other cysteine-scanning mutants retained normal drug resistance and normal tetracycline transport activity except for the L142C and I143C mutants. The transmembrane (TM) regions TM4 and TM5 were determined to comprise 20 amino acid residues, Leu-99 to Ile-118, and 17 amino acid residues, Ala-136 to Ala-152, respectively, on the basis of N-[(14)C]ethylmaleimide ([(14)C]NEM) reactivity. The NEM reactivity patterns of the TM4 and TM5 mutants were quite different from each other. TM4 could be divided into two halves, that is, a NEM nonreactive periplasmic half and a periodically reactive cytoplasmic half, indicating that TM4 is tilted toward a water-filled transmembrane channel and that only its cytoplasmic half faces the channel. On the other hand, NEM-reactive mutations were observed periodically (every two residues) along the whole length of TM5. A permeability barrier for a membrane-impermeable sulfhydryl reagent, 4-acetamido-4'-maleimidylstilbene-2,2'-disulfonic acid, was present in the middle of TM5 between Leu-142 and Gly-145, whereas all the NEM-reactive mutants as to TM4 were not accessible to 4-acetamido-4'-maleimidylstilbene-2,2'-disulfonic acid, indicating that the channel-facing side of TM4 is located inside the permeability barrier. Tetracycline protected the G141C mutant from the NEM binding, whereas the other mutants in TM4 and TM5 were not protected by tetracycline.

We report photoluminescence and time-resolved photoluminescence measurements of GaN multiple quantum wells (QWs) with AlxGa1–xN barriers of high aluminium content. GaN/Al0.8Ga0.2N samples were grown with well widths as low as one monolayer, giving photoluminescence of peak energy 5.03 eV (247 nm) at room temperature. A study of lifetimes in GaN/Al0.5Ga0.5N samples shows low temperature recombination to be dominated by radiative processes with lifetimes 0.5 ns in 1 to 2 nm wells. Dependence of lifetime on emission energy is very small compared to InGaN QWs, indicating that carrier localization is very slight and interface quality is high. In 4 nm wells, PL emission at an energy below the bulk GaN band gap and long recombination lifetimes result from the polarization field across the wells.

We reported that the positive charge of Arg(70) is mandatory for tetracycline transport activity of Tn10-encoded metal-tetracycline/H(+) antiporter (TetA(B)) (Someya, Y., and Yamaguchi, A. (1996) Biochemistry 35, 9385-9391). Arg(70) may function through a charge-pairing with a negatively charged residue in close proximity. Therefore, we mutated Asp(66) and Asp(120), which are only two negatively charged residues located close to Arg(70) in putative secondary structure of TetA(B) and highly conserved throughout transporters of the major facilitator superfamily. Site-directed mutagenesis studies revealed that Asp(66) is essential, but Asp(120) is important for TetA(B) function. Surprisingly, when Asp(120) was replaced by a neutral residue, the R70A mutant recovered tetracycline resistance and transport activity. There was no such effect in the Asp(66) mutation. The charge-exchanged mutant, R70D/D120R, also showed significant drug resistance and transport activity (about 50% of the wild type), although the R70D mutant had absolutely no activity, and the D120R mutant retained very low activity (about 10% of the wild type). Both the R70C and D120C mutants were inactivated by N-ethylmaleimide. Mercuric ion (Hg(2+)), which gives a positive charge to a SH group of a Cys residue through mercaptide formation, had an opposite effect on the R70C and D120C mutants. The activity of the R70C mutant was stimulated by Hg(2+); however, on the contrary, the D120C mutant was partially inhibited. On the other hand, the R70C/D120C double mutant was almost completely inactivated by Hg(2+), probably because the side chains at positions 70 and 120 are bridged with Hg(2+). The close proximity of positions 70 and 120 were confirmed by disulfide cross-linking formation of the R70C/D120C double mutant when it was oxidized by copper-(1,10-phenanthroline). These results indicate that the positive charge of Arg(70) requires the negative charge of Asp(120) for neutralization, probably for properly positioning transmembrane segments in the membrane.

We have successfully grown a stacked InGaN quantum dot (QD) structure for laser applications, using atmospheric-pressure metalorganic chemical vapor deposition. The average diameter and height of typical InGaN QDs are 18 nm and 3 nm, respectively. The density of the single-layer QDs is 1.2 × 1010 cm—2. InGaN QDs are formed even when the number of stacked layers is 10. We have also investigated the photoluminescence from the stacked QDs at room temperature. The photoluminescence intensity increases drastically as the number of layers increases. This improvement of photoluminescence intensity leads to lasing action in InGaN QD lasers at room temperature.

We have successfully fabricated post-type InGaN VCSEL structures and observed their room temperature oscillation at 399 nm under optical excitation. The nitride structures were grown by atmospheric-pressure metalorganic chemical vapor deposition (MOCVD). X-ray diffraction (XRD) was employed to characterize nitride Bragg reflectors. Lasing action was unambiguously confirmed by significant narrowing in emission spectra from 0.8 to less than 0.1 nm (resolution limit).

Parenting styles can influence an individual's ability to cope with stress; consequently, coping strategies may moderate the interaction between stress and psychiatric disorders. The correlation between perceived parenting styles and stress-coping strategies in 50 outpatients in remission from major depressive disorders was investigated. Using multiple regression analysis including symptoms, gender and age of subjects as independent variables, maternal care and male gender were significant variables for predicting task-oriented coping strategies (p&lt;0.05). Low maternal care and highly overprotective parenting were significant variables for predicting emotion-oriented coping strategies (p&lt;0.05). These findings suggest that perceived parenting styles of the mother experienced in childhood may be related to stress-coping styles in adulthood. It should nevertheless be considered whether parents' actual child-rearing methods affect their offspring's ability to cope with stress or whether an individual who retrospectively perceives a lack of parental affection tends to use more emotion-oriented coping and less task-oriented coping. Copyright © 1999 John Wiley & Sons, Ltd.

Influences of the thickness of Si-doped n-type AlxGa1—xN barrier and the thickness of the AlxGa1—xN spacer on mobility and density of a two-dimensional electron gas (2DEG) in modulation doped Al0.15Ga0.85N/GaN heterostructures were investigated. 2DEG mobilities of 1274 cm2/Vs at 300 K and 4495 cm2/Vs at 77 K were reached. Both 2DEG mobility and density decrease dramatically when the AlxGa1—xN barrier layer is relaxed, indicating that the transport properties of 2DEG are influenced significantly by the piezoelectric polarization of the AlxGa1—xN layer. The critical thickness of the Al0.15Ga85N layer on GaN is between 65 nm and 75 nm, which is much higher than that predicted from theoretical calculations. It may be attributed to the interaction between misfit dislocations in the AlxGa1—xN layer.

We report time-resolved photoluminescence measurements on InxGa1—xN/InyGa1—yN single quantum wells with different levels of silicon doping. Remarkable decay behaviour is observed in samples with zero or low doping and at high excitation powers: carrier lifetimes which decrease with time after the laser pulse. The results can be attributed to photoexcited carriers giving time-dependent screening of the polarization field and to doping giving permanent screening.

Cysteine-scanning mutants, E32C to G62C, of the metal-tetracycline/H+ antiporter were constructed in order to precisely determine the membrane topology around putative transmembrane segment II. None of the mutants lost the ability to confer tetracycline resistance, indicating that the cysteine mutation in each mutant did not alter the protein conformation. [14C]N-Ethylmaleimide (NEM) binding to these cysteine mutants in isolated membranes was then investigated. The peptide chain of this region passes through the membrane at least once because residues 36 and 65 are exposed on the outside and inside surfaces of the membrane, respectively (Kimura, T., Ohnuma, M., Sawai, T., and Yamaguchi, A. (1997) J. Biol. Chem. 272, 580-585). However, there was no continuous segment in which all of the introduced cysteine residues showed almost no reactivity with [14C]NEM. The proportion of the unbound positions in the second half downstream from position 45 was 55% (10/18), which was clearly higher than that in the first half (21%; 3/14), suggesting that the second half is a transmembrane segment. Positions reactive to NEM appear periodically in the second half. They are located on one side of the helical wheel, suggesting that this side of the transmembrane helix faces a water-filled channel. The cysteine mutants as to the reactive positions in the second half were severely inactivated by NEM except for the P59C mutant, whereas the A40C mutant was the only one inactivated by NEM in the first half. These results suggest that the water-filled channel along this helical region may be a substrate translocation pathway.

This paper describes our recent studies to design and epitaxially synthesize 10nm-scale quantum wire (QWR) structures and to clarify their transport and optical properties. We discuss first the epitaxial growth and physics study of both field-induced edge QWRs as well as T-shaped edge QWRs. We, then, propose two new edge QWR structures in which electric fields play greater roles in the carrier confinement. We then summarize our recent work on step QWRs, in which periodic bunched steps on a (111) B GaAs plane modulate the motion of 2D electrons at n-AlGaAs/GaAs heterojunctions. Finally, we discuss several approaches by which 10nm-scale QDs are formed by the extended use of epitaxial techniques originally developed for the fabrication of QWRs.

Accurate measurements of gyration tensors g11 (=-g22) and electrogyration effect of KH2PO4 were made by applying the improved HAUP method. g11 diverges conspicuously when the temperature approaches Tc from above and below it, the behaviour being analyzed as obeying the Curie-Weiss law with a Curie-Weiss constant of 7.35×10-4 K. An electrogyration coefficient π13 referring to the polarization manifests a characteristic nature of improper ferroelectrics.

Lemon oil contains furocoumarin derivatives and is known to cause phototoxicity. In this study, lemon oil was fractionated, and its phototoxic activity was measured by means of a biological assay. The substances producing phototoxicity were identified by high-performance liquid chromatography as being oxypeucedanin and bergapten. The phototoxic potency of oxypeucedanin was only one-quarter of that of bergapten. However, the amounts of these two phototoxic compounds present in lemon oils produced in different regions of the world varied by a factor of more than 20 (bergapten, 4–87 ppm; oxypeucedanin, 26–728 ppm), and their ratio was not constant. The two compounds accounted for essentially all of the phototoxic activity of all lemon-oil samples. Among various other citrus-essential oils investigated, lime oil and bitter-orange oil also contained large amounts of oxypeucedanin. Oxypeucedanin was found to elicit photopigmentation on colored-guinea-pig skin without preceding visible erythema.

The self-excited vibration of a rotating hollow shaft partially filled with viscous liquid is investigated. The motion of liquid and the liquid force is analyzed. The stability of the rotor system is calculated and the influences of factors on the stability are studied. Moreover, the mechanism causing the negative damping which is the reason for the instability is discussed.

After a brief historical review on edge quantum wire (QWR) structures, we report on our systematic study to prepare and investigate a series of GaAs/AlGaAs and GaAs/AlAs T-shaped edge QWRs. In particular, we examine various features of one-dimensional excitons, such as their binding energy, optical anisotropy, and shrinkage of wavefunctions, and discuss both potentials and challenges of this approach. We describe also our recent work on a novel resonant tunneling structure where electrostatically induced QWR states are involved. We compare this T-shaped QWR approach and its extension to quantum dot structures with other epitaxial growth techniques of nanostructures.

(1) Whole-cell and single channel recording techniques have been applied to smooth muscle cells isolated from guinea-pig taenia coli to examine whether multiple types of Ca channels exist. (2) Whole-cell recordings under physiological Ca concentration (1.8 mM) revealed two current components with fast and slow inactivating kinetics. The fast inactivating component was present when cells were held at very negative potentials (-80 mV). It was insensitive to the dihydropyridine (DHP) derivative, nifedipine. In contrast, the slow inactivating component was present at less negative holding potentials. It was blocked by nifedipine. (3) The two current components were found to have closely similar voltage dependencies for activation. (4) These results suggest that the fast inactivating decay of the Ca current was mediated not only by the entry of Ca into the cell but also by a voltage-dependent process via a different type of Ca channel with fast inactivating kinetics. (5) Recordings from cell-attached membrane patches with 100 mM external Ba clearly showed the existence of multiple types of Ca channels with different conductances. (6) The large conductance channels (30 pS) activated at more positive potentials (0 mV) and their averaged current decayed much more slowly. The DHP Ca antagonist, nifedipine, inhibited the large conductance channels increasing the proportion of blank sweeps and reducing the averaged current. On the other had, the DHP Ca-agonist, BayK 8644, increased the averaged current by increasing the mean open-times of the large conductance channels. The presence of micromolar Cd in the patch pipettes produced a flickering block of the large conductance channels. (7) The small conductance channels (7 pS) activated at more negative potentials (-40 mV ~30 mV) and the averaged current decayed rapidly within 100 ms. They showed no sensitivity to nifedipine and Cd ions. (8) In summary, we have identified at least two distinct types of Ca channels with different conductances, different pharmacological sensitivities, and different voltage- and time-dependent kinetics in smooth muscle cells isolated from guinea-pig taenia coli. The large and small conductance channels could be classified asl- andt-type Ca channels, respectively, which have been described in neuronal and heart cells. The contribution of those channels to the macroscopic component of whole-cell Ca current is also discussed.

By applying the improved HAUP method, measurements of gyration tensor g11 of KH2PO4 (KDP) were made with application of biasing electric fields up to 20 kv/cm. It was found that the gyration tensor with zero electric field manifests a sharp peak at Tc and it becomes depressed depending on magnitude of the electric fields. Moreover, gyration tensor g11 of KD2PO4 (DKDP) was measured, and it was confirmed that the temperature dependence of the gyration tensor obeys the Curie-Weiss law as is the case with KDP. Then the Curie constants for KDP and DKDP were obtained as 6.90 × 10-4 K and 1.10 × 10-3 K respectively.

Das Problem der sogenannten Lagerinstabilität wurde rechnerisch untersucht. Als Vorbereitung wurde der Schmiermitteldruck und die Feder- und Dämpfungskonstanten des Schmierfilms berechnet. Die lineare Stabilitätsrechnung ergab, daß die Größe des Breitenverhältnisses β die Stabilitätsgrenzkurve nur wenig, die Anfahrkurve jedoch stark beeinflußt. Wie man aus dem Verlauf der Grenzkurven ersieht, muß man bei der Stabilisierung eines instabilen Gleichgewichtes zwei Fälle unterscheiden: Beim leicht belasteten Lager ist das Lagerspiel Δr zu verkleinern und die Eigenfrequenz ωk der Welle zu erhöhen, beim schwer belasteten Lager ist die Zähigkeit und die Lagerbreite B zu verkleinern und das Lagerspiel Δr zu vergrößern. Die nichtlineare Bahnberechnung ergab: Auch wenn nach linearer Rechnung das Gleichgewicht stabil ist, kann bei höheren Drehzahlen eine hinreichend große Anfangsstörung Instabilität hervorrufen. Die Bahnkurven werden bei Instabilität mit wachsender Amplitude mehr und mehr kreisförmig. Dabei stellt sich bei Drehzahlen unter 2 ωk die Halbdrehfrequenzschwingung mit einer endlichen Rotoramplitude ein, während bei Drehzahlen über 2 ωk die Eigenfrequenzschwingung entsteht, deren Amplitude unaufhörlich anwächst. Dieses Anwachsen beruht auf einer durch den Schmiermitteldruck bedingten Energiezufuhr. Soll also in Wirklichkeit die Amplitude endlich bleiben, so muß eine äußere Dämpfung auf die Welle wirken. Für einen einfachen Dämpfungsansatz wurde daher abschließend die stationäre, kreisförmige Wellenschwingung berechnet, wobei sich wiederum die Halbdrehfrequenz- und die Eigenfrequenzschwingung ergaben. Für große Werte des Parameters Λ/√μ nimmt danach die Rotoramplitude mit der Drehzahl zu, für kleine Λ/√μ-Werte nimmt sie dagegen nach Überschreiten eines Maximums wieder ab. In diesem Falle läßt sich die Rotoramplitude auch durch ein Verkleinern des Parameters Λ/√μ vermindern. Die bisher bekannten Versuchsergebnisse scheinen die Rechenergebnisse zu bestätigen.

Für zylindrische Gleitlager beliebigen Querschnittes wurde gezeigt, wie man bei vorgegebener, zeitlich veränderlicher Belastung die Bahnkurven des Zapfenmittelpunktes im Lagerspielraum berechnen kann. Im Vergleich zum kreiszylindrischen Gleitlager tritt dabei in der Reynoldsschen Gleichung eine allgemeine Lagerspaltfunktion $$\bar H(\varphi )$$ auf. Unter der Randbedingung, daß der Schmiermitteldruck an den Lagerkanten und Quernuten verschwinden soll, wird die Reynoldssche Gleichung gelöst und daraus die Druckkraft ermittelt. Für die Bewegung des Zapfenmittelpunktes erhält man ein System von zwei impliziten Differentialgleichungen. Sie werden durch Iteration explizit gemacht und numerisch integriert.

We are pleased to introduce the September issue of Current Pharmacogenomics and Personalized Medicine (CPPM) and share with you the editorial vision of the Journal as an integrated new title addressing both pharmacogenomics and personalized medicine readership effective 2008. CPPM has a unique focus on the complex challenges and promises emerging from the fusion of knowledge domains in therapeutics and diagnostics (i.e., theragnostics) in postgenomics medicine. The Journal covers issues relating to individual and population variability in drug treatment outcomes and disease susceptibility. A firm understanding of these variability questions is a prerequisite and essential foundation to achieve the overarching goal of personalized therapeutics [1-4]. We bear in mind the increasingly globalized nature of health research and services, and the diverse technologies, stakeholders and interdisciplinary expertise that collectively drive the rapidly evolving knowledge frontiers in personalized medicine. The September issue in front of you features articles that offer a transdisciplinary synthesis of the recent developments in the field. Tikki Pang asks the question if it is “too soon”, or “just-in-time” for the developing countries to consider the applications of pharmacogenomics in dealing with priority health problems. In the face of genomics research that now extends well beyond the laboratory bench to global society [5, 6], and pandemics that do not recognize national and geographical borders [7], this article makes a timely contribution at the unique intersection of personalized medicine and global public health. Following on the latter theme, Muin Khoury provides an in-depth account of the public health genomics, a multidisciplinary field concerned with the effective and responsible applications of genome-based knowledge and technologies to improve population health.