879 research outputs found
Work-in-Progress: Determining MPSoC Layout from Thermal Camera Images
In many safety-critical applications, Multi-Processor Systems-on-
Chip (MPSoC) must operate within a given thermal envelope under
harsh environmental conditions. Meeting the thermal requirements
often requires using advanced task allocation and scheduling techniques
that are guided by detailed power models. This paper introduces
a method that has the potential to simplify the creation
of such models. It constructs so-called heat maps from thermal
camera images. By comparing the heat maps of different workloads,
we identify the locations of on-chip components and the amount
of heat produced by them. We demonstrate our method on the
i.MX8QuadMax chip from NXP, where we identify the locations of
CPU clusters, bigger CPU cores, GPUs, and DRAM controllers
Design thinking as driver for innovation in the chemical industry
In a time of increasing market pressure, managers value innovations as a precious currency. While shifting the focus away from incremental innovations at the level of molecules, companies in the chemical industry should consider a more systematic approach to the development of ideas during the innovation processes. However, solely aligning all research activities with the upcoming megatrends for the industry is not sufficient. This article empirically demonstrates the strategic relevance of Design Thinking as a method to not only overcome typical barriers in the innovation process but also to guide stakeholders through all iterative stages required for innovation
Comparing charge transfer tuning effects by chemical substitution and uniaxial pressure in the organic charge transfer complex tetramethoxypyrene-tetracyanoquinodimethane
In the search for novel organic charge transfer salts with variable charge
transfer degree we study the effects of two modifications to the recently
synthesized donor-acceptor Tetramethoxypyrene (TMP)-Tetracyanoquinodimethane
(TCNQ). One is of chemical nature by substituting the acceptor TCNQ molecules
by F4TCNQ molecules. The second consists in simulating the application of
uniaxial pressure along the stacking axis of the system. In order to test the
chemical substitution, we have grown single crystals of TMP-F4TCNQ and analyzed
its electronic structure via electronic transport measurements, ab initio
density functional theory (DFT) calculations and UV/VIS/IR absorption
spectroscopy. This system shows an almost ideal geometrical overlap of nearly
planar molecules alternately stacked (mixed stack) and this arrangement is
echoed by a semiconductor-like transport behavior with an increased
conductivity along the stacking direction. This is in contrast to TMP-TCNQ
which shows a less pronounced anisotropy and a smaller conductivity response.
Our bandstructure calculations confirm the one-dimensional behavior of
TMP-F4TCNQ with pro- nounced dispersion only along the stacking axis. Infrared
measurements illustrating the CN vibration frequency shift in F4TCNQ suggest
however no improvement on the degree of charge transfer in TMP-F4TCNQ with
respect to TMP-TCNQ. In both complexes about 0.1 is transferred from TMP to the
acceptor. Concerning the pressure effect, our DFT calculations on designed
TMP-TCNQ and TMP-F4TCNQ structures under different pressure conditions show
that application of uniaxial pressure along the stacking axis of TMP-TCNQ may
be the route to follow in order to obtain a much more pronounced charge
transfer
Association of Gene Variants for Mechanical and Metabolic Muscle Quality with Cardiorespiratory and Muscular Variables Related to Performance in Skiing Athletes
BACKGROUND
Skiing is a popular outdoor sport posing different requirements on musculoskeletal and cardiorespiratory function to excel in competition. The extent to which genotypic features contribute to the development of performance with years of ski-specific training remains to be elucidated. We therefore tested whether prominent polymorphisms in genes for angiotensin converting enzyme (ACE-I/D, rs1799752), tenascin-C (TNC, rs2104772), actinin-3 (ACTN3, rs1815739) and PTK2 (rs7460 and rs7843014) are associated with the differentiation of cellular hallmarks of muscle metabolism and contraction in high level skiers.
MATERIAL & METHODS
Forty-three skiers of a world-leading national ski team performed exhaustive cardiopulmonary exercise testing as well as isokinetic strength testing for single contractions, whereby 230 cardiopulmonary measurements were performed in the period from 2015-2018. A total of 168 and 62 data measurements were from the Alpine and Nordic skiing squads, respectively. Ninety-five and one hundred thirty-five measurements, respectively, were from male and female athletes. The average (±SD) age was 21.5 ± 3.0 years, height 174.0 ± 8.7 cm, and weight 71.0 ± 10.9 kg for the analysed skiers. Furthermore, all skiers were analysed concerning their genotype ACE-I/D, Tenascin C, ACTN3, PTK2.
RESULTS
The genotype distribution deviated from Hardy-Weinberg equilibrium for the ACTN3 genotype, where rs1815739-TT genotypes (corresponding to the nonsense mutation) were overrepresented in world-class skiers, indicating a slow muscle fibre phenotype. Furthermore, the heterozygous rs2104772-AT genotypes of TNC also demonstrated the best scaled peak power output values during ramp exercise to exhaustion. The highest values under maximum performance for heart rate were associated with the rs1799752-II and rs1815739-CC genotypes. The lowest values for peak power of single contractions were achieved for rs1815739-CC, rs1799752-II and rs7843014-CT genotypes. The skiing discipline demonstrated a main influence on cardiorespiratory parameters but did not further interact with genotype-associated variability in performance.
DISCUSSION
Classically, it is pointed out that muscles of, for example, alpine skiers do not possess a distinct fibre type composition, but that skiers tend to have a preponderance of slow-twitch fibres. Consequently, our findings of an overrepresentation of ACTN3-TT genotypes in a highly selective sample of elite world class skiers support the potential superiority of a slow fibre type distribution.
CONCLUSIONS
We suggest that one competitive advantage that results from a slow, typically fatigue-resistant fibre type distribution might be that performance during intense training days is better preserved, whereby simply a higher technical training volume can be performed, yielding to a competitive advantage
Eliminating Recursion from Monadic Datalog Programs on Trees
We study the problem of eliminating recursion from monadic datalog programs
on trees with an infinite set of labels. We show that the boundedness problem,
i.e., determining whether a datalog program is equivalent to some nonrecursive
one is undecidable but the decidability is regained if the descendant relation
is disallowed. Under similar restrictions we obtain decidability of the problem
of equivalence to a given nonrecursive program. We investigate the connection
between these two problems in more detail
Association of Gene Variants with Seasonal Variation in Muscle Strength and Aerobic Capacity in Elite Skiers
Background: The training of elite skiers follows a systematic seasonal periodization with a preparation period, when anaerobic muscle strength, aerobic capacity, and cardio-metabolic recovery are specifically conditioned to provide extra capacity for developing ski-specific physical fitness in the subsequent competition period. We hypothesized that periodization-induced alterations in muscle and metabolic performance demonstrate important variability, which in part is explained by gene-associated factors in association with sex and age. Methods: A total of 34 elite skiers (20.4 ± 3.1 years, 19 women, 15 men) underwent exhaustive cardiopulmonary exercise and isokinetic strength testing before and after the preparation and subsequent competition periods of the World Cup skiing seasons 2015-2018. Biometric data were recorded, and frequent polymorphisms in five fitness genes, ACE-I/D (rs1799752), TNC (rs2104772), ACTN3 (rs1815739), and PTK2 (rs7460, rs7843014), were determined with specific PCR reactions on collected DNA. Relative percentage changes of cardio-pulmonary and skeletal muscle metabolism and performance over the two seasonal periods were calculated for 160 data points and subjected to analysis of variance (ANOVA) to identify hypothesized and novel associations between performance alterations and the five respective genotypes and determine the influence of age × sex. A threshold of 0.1 for the effect size (h2) was deemed appropriate to identify relevant associations and motivate a post hoc test to localize effects. Results: The preparation and competition periods produced antidromic functional changes, the extent of which varied with increasing importance for anaerobic strength, aerobic performance, cardio-metabolic efficiency, and cardio-metabolic/muscle recovery. Only peak RER (-14%), but not anaerobic strength and peak aerobic performance, and parameters characterizing cardio-metabolic efficiency, differed between the first and last studied skiing seasons because improvements over the preparation period were mostly lost over the competition period. A number of functional parameters demonstrated associations of variability in periodic changes with a given genotype, and this was considerably influenced by athlete "age", but not "sex". This concerned age-dependent associations between periodic changes in muscle-related parameters, such as anaerobic strength for low and high angular velocities of extension and flexion and blood lactate concentration, with rs1799752 and rs2104772, whose gene products relate to sarcopenia. By contrast, the variance in period-dependent changes in body mass and peak VO2 with rs1799752 and rs2104772, respectively, was independent of age. Likely, the variance in periodic changes in the reliance of aerobic performance on lactate, oxygen uptake, and heart rate was associated with rs1815739 independent of age. These associations manifested at the post hoc level in genotype-associated differences in critical performance parameters. ACTN3 T-allele carriers demonstrated, compared to non-carriers, largely different periodic changes in the muscle-associated parameters of aerobic metabolism during exhaustive exercise, including blood lactate and respiration exchange ratio. The homozygous T-allele carriers of rs2104772 demonstrated the largest changes in extension strength at low angular velocity during the preparation period. Conclusions: Physiological characteristics of performance in skiing athletes undergo training period-dependent seasonal alterations the extent of which is largest for muscle metabolism-related parameters. Genotype associations for the variability in changes of aerobic metabolism-associated power output during exhaustive exercise and anaerobic peak power over the preparation and competition period motivate personalized training regimes. This may help to predict and maximize the benefit of physical conditioning of elite skiers based on chronological characteristics and the polymorphisms of the ACTN3, ACE, and TNC genes investigated here
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