A computer graphics course for the two cultures

The subject of computer graphics offers a special educational opportunity for bringing together students from the two cultures of the arts/humanities and of the sciences/technologies. The author describes a computer graphics course with this approach. Several important problems arise because of students' varying backgrounds in programming and their expectations, the lack of suitable texts, and the lack of suitably-oriented computer graphics centers. The course schedule is composed of lectures, discussions of readings, and workshops in a computer graphics facility. The hardware and software basis of the course is flexible. Students complete an assigned initial project, a final project of their choice, and are responsible for documenting their project visually and verbally before the close of the semester. Student performance and evaluation of the course suggest this cross-cultural approach is a valid, worthwhile experiment to introduce the structure and significance of computer graphics imagery and computer graphics display systems.     

Leukocyte reactions "in vitro" to human spermatozoa in infertile females

Leucocyte migration test was done in 55 couples facing fertility problems for detection of antispermatozoal cellular hypersensitivity. In 29 cases out of 55, the sterility was unexplained and in 26 cases out of 55, various infertility factors were found. In this study, wife's leucocytes separated on Ficoll-Urografin gradient were incubated (4.10(6) per capillary) with washed fresh husband's spermatozoa suspended at 7.10(6)/ml in M 199 and 20 p. 100 fetal bovine serum. The results were read after 18h. Two kinds of migration inhibition were found: 1) Specific wives leucocyte migration inhibition in 4 out of 55 cases, all of them unexplained infertility cases. 2) Leucocyte migration inhibition not related to wife's immunity state and possibly due to a direct effect of a toxic or inhibitory property of some husband's spermatozoa in 22 out of 55 cases, 11/19 cases with known male factors, and 11/36 cases without any male factor. In the follow up, only 1 woman out of the 22 couples with husband's spermatozoal inhibitory factor was pregnant later, while in the group of 29 women in which normal leucocyte spreading was found, 8 women conceived later. No woman out of the 4 suspected of antispermatozoal delayed hypersensitivity have conceived. Attention must be paid to the possible role of delayed hypersensitivity to sperm in unexplained infertility and also to the occurrence of spermatozoal toxic factor and its possible implications on human infertility.     

Relationships between the fatty acid composition of muscle and erythrocyte membrane phospholipid in young children and the effect of type of infant feeding

Muscle membrane fatty acid (FA) composition is linked to insulin action. The aims of this study were to compare the FA composition of muscle and erythrocyte membrane phospholipid in young children; to investigate the effect of diet on these lipid compositions; and to investigate differential incorporation of FA into muscle, erythrocyte and adipose tissue membrane phospholipid, and adipose tissue triglyceride. Skeletal muscle biopsies and fasting blood samples were taken from 61 normally nourished children (15 males and 16 females), less than 2 yr old (means ±SE, 0.80±0.06 yr), undergoing elective surgery. Adipose tissue samples were taken from 15 children. There were significant positive correlations between muscle and erythrocyte docosahexaenoic acid (DHA) (r=0.44, P<0.0001), total n−3 polyunsaturated fatty acids (PUFA) (r=0.39, P=0.002), and the n−6/n−3 PUFA ratio (r=0.39, P=0.002). Adipose tissue triglyceride had lower levels of long-chain PUFA, especially DHA, than muscle and erythrocytes (0.46±0.18% vs. 2.44±0.26% and 3.17±0.27%). Breast-fed infants had higher levels of DHA than an age-matched group of formulafed infants in both muscle (3.91±0.21% vs. 1.94±0.18%) and erythrocytes (3.81±0.10% vs. 2.65±0.23%). The results of this study show that (i) erythrocyte FA composition is a reasonable index of muscle DHA, total n−3 PUFA, and the n−6/n−3 PUFA ratio; (ii) breast feeding has a potent effect on the FA composition of all these tissues; and (iii) there is a wide range in long-chain PUFA levels in muscle, erythrocytes, and adipose tissue.     

Self‐Assembled Heterostructures: Selective Growth of Metallic Nanoparticles on V2–VI3 Nanoplates

Precise control of the selective growth of heterostructures with specific composition and functionalities is an emerging and extremely challenging topic. Here, the first investigation of the difference in binding energy between a series of metal–semiconductor heterostructures based on layered V₂–VI₃ nanostructures is investigated by means of density functional theory. All lateral configurations show lower formation energy compared with that of the vertical ones, implying the selective growth of metal nanoparticles. The simulation results are supported by the successful fabrication of self‐assembled Ag/Cu‐nanoparticle‐decorated p‐type Sb₂Te₃ and n‐type Bi₂Te₃ nanoplates at their lateral sites through a solution reaction. The detailed nucleation–growth kinetics are well studied with controllable reaction times and precursor concentrations. Accompanied by the preserved topological structure integrity and electron transfer on the semiconductor host, exceptional properties such as dramatically increased electrical conductivity are observed thanks to the pre‐energy‐filtering effect before carrier injection. A zigzag thermoelectric generator is built using Cu/Ag‐decorated Sb₂Te₃ and Bi₂Te₃ as p–n legs to utilize the temperature gradient in the vertical direction. Synthetic approaches using similar chalcogenide nanoplates as building blocks, as well as careful control of the dopant metallic nanoparticles or semiconductors, are believed to be broadly applicable to other heterostructures with novel applications.     

Multinationality and Performance: A Context-Specific Analysis for German Firms

The development of foreign markets can be considered as a strategic key factor in times of globalisation. However, past empirical research could not detect a “universal” relationship between corporate multinationality and performance. There exist fundamental doubts whether the contextual condition of internationalisation of one empirical setting can be easily transferred to another setting for investigating the relationship between multinationality and performance. For instance, potentials for realising economies of scale in the home market and abroad, the degree of integration of neighbouring countries, as well as the accumulated internationalisation experience, can differ significantly from each other between countries. Taking into account the contextual conditions of internationalisation of stock-listed German firms in the time period from 1990 to 2006, this paper analyses the performance effects of firms’ multinationality. Firms of this sample can benefit from multinationality even in early internationalisation stages and are able to manage high degrees of complexity in later internationalisation stages successfully. Firm-specific advantages in the field of intangible assets with long-term (short-term) effects moderate the relationship between multinationality and future-oriented (past-oriented) performance positive.     

Enhanced damage classification accuracy on a transmission by extending existing datasets with generative adversarial networks

In many areas of drive technology, condition monitoring of transmissions and drive systems is becoming an increasingly important discipline. Condition monitoring systems are used in many cases in combination with machine learning algorithms. The generation of a sufficient amount of data per condition class is relevant to ensure training stability and accuracy of the applied algorithms. Especially in early development phases a sufficient data generation is not often given. In the scope of this paper, a Generative Adversarial Network is applied to generate synthetic data and therefore extend existing measurement data sets. Acceleration data in three different condition classes is used, that has been collected on a gearbox as part of the PHM Data Challenge 2009. In order to highlight relevant features and reduce the number of data points, data is pre-processed via appropriate signal analysis techniques, in this case with the spectral kurtosis. It is shown, that in this use case the synthetically generated data via a Generative Adversarial Network has the same feature characteristics as the real measured data sets. The augmentation of the existing data set also improves the detection accuracy with artificial neural networks for the classification of different system states.

     

Academics’ “ambidextrous behavior” and doctoral science mentoring practices

Although academics (academic scientists) are the vanguards in mentoring doctoral science students, emergent science policies increasingly push academics to venture into industrial science work with industrial scientists. This puts academics in a situation of heightened role strain given that academic life is already exacting in terms of teaching, research, and service. Now, academics have to balance between intrinsic and extrinsic demands. In this paper, we examine how academics’ involvement in academic and in industrial science activities impacts how academic scientists mentor doctoral students. We introduce the idea of academics’ “ambidextrous behavior” and apply it in three scientific activities, namely: (1) formally collaborating in academic and in industrial research projects, (2) informally networking with academic and with industrial scientists, and (3) producing patents and publications. We test the hypothesis that academics, who exhibit ambidextrous behavior, manifest mentoring practices that differ from colleagues who do not exhibit such behavior. We adduce evidence from a face-to-face survey of 104 East Asian chemical science professors, and analyze data using principal component and regression analyses. Our results provide insights on how academics’ involvement in both academic and industrial science activities shapes the way doctoral students are mentored. Our work also exemplifies how the concept of ambidextrous behavior can be applied in examining aspects of scientific apprenticeship in academia at a time when knowledge production increasingly takes place at the intersecting sectors of Etzkowitz’s (Res Policy 27(8):823–833, 1998) Triple Helix science (i.e., academia, government, and industry).     

Small‐Scale Machines Driven by External Power Sources

Micro‐ and nanorobots have shown great potential for applications in various fields, including minimally invasive surgery, targeted therapy, cell manipulation, environmental monitoring, and water remediation. Recent progress in the design, fabrication, and operation of these miniaturized devices has greatly enhanced their versatility. In this report, the most recent progress on the manipulation of small‐scale robots based on power sources, such as magnetic fields, light, acoustic waves, electric fields, thermal energy, or combinations of these, is surveyed. The design and propulsion mechanism of micro‐ and nanorobots are the focus of this article. Their fabrication and applications are also briefly discussed.