110 research outputs found
KIM-Servicepunkt in der Bibliothek
Den KIM-Servicepunkt in der Bibliothek B400 gibt es seit April 2007. Zunächst wurde er durch studentische Hilfskräfte besetzt, bis unsere Stellen geschaffen wurden. Seit Oktober 2007 sind wir (Anke Stehle, Frank Heibel und Roberto Hirche) für den Servicepunkt zuständig
Fast IMU-based Dual Estimation of Human Motion and Kinematic Parameters via Progressive In-Network Computing
Many applications involve humans in the loop, where continuous and accurate
human motion monitoring provides valuable information for safe and intuitive
human-machine interaction. Portable devices such as inertial measurement units
(IMUs) are applicable to monitor human motions, while in practice often limited
computational power is available locally. The human motion in task space
coordinates requires not only the human joint motion but also the nonlinear
coordinate transformation depending on the parameters such as human limb
length. In most applications, measuring these kinematics parameters for each
individual requires undesirably high effort. Therefore, it is desirable to
estimate both, the human motion and kinematic parameters from IMUs. In this
work, we propose a novel computational framework for dual estimation in
real-time exploiting in-network computational resources. We adopt the concept
of field Kalman filtering, where the dual estimation problem is decomposed into
a fast state estimation process and a computationally expensive parameter
estimation process. In order to further accelerate the convergence, the
parameter estimation is progressively computed on multiple networked
computational nodes. The superiority of our proposed method is demonstrated by
a simulation of a human arm, where the estimation accuracy is shown to converge
faster than with conventional approaches
Expression of genes involved in hepatic carnitine synthesis and uptake in dairy cows in the transition period and at different stages of lactation
<p>Abstract</p> <p>Background</p> <p>In rodents and pigs, it has shown that carnitine synthesis and uptake of carnitine into cells are regulated by peroxisome proliferator-activated receptor α (PPARA), a transcription factor which is physiologically activated during fasting or energy deprivation. Dairy cows are typically in a negative energy balance during early lactation. We investigated the hypothesis that genes of carnitine synthesis and uptake in dairy cows are enhanced during early lactation.</p> <p>Results</p> <p>mRNA abundances of PPARA and some of its classical target genes and genes involved in carnitine biosynthesis [trimethyllysine dioxygenase (TMLHE), 4-N-trimethylaminobutyraldehyde dehydrogenase (ALDH9A1), γ-butyrobetaine dioxygenase (BBOX1)] and uptake of carnitine [novel organic cation transporter 2 (SLC22A5)] as well as carnitine concentrations in liver biopsy samples of 20 dairy cows in late pregnancy (3 wk prepartum) and early lactation (1 wk, 5 wk, 14 wk postpartum) were determined. From 3 wk prepartum to 1 wk postpartum, mRNA abundances of PPARΑ and several PPARΑ target genes involved in fatty acid uptake, fatty acid oxidation and ketogenesis in the liver were strongly increased. Simultaneously, mRNA abundances of enzymes of carnitine synthesis (TMLHE: 10-fold; ALDH9A1: 6-fold; BBOX1: 1.8-fold) and carnitine uptake (SLC22A5: 13-fold) and the concentration of carnitine in the liver were increased from 3 wk prepartum to 1 wk postpartum (<it>P </it>< 0.05). From 1 wk to 5 and 14 wk postpartum, mRNA abundances of these genes and hepatic carnitine concentrations were declining (<it>P </it>< 0.05). There were moreover positive correlations between plasma concentrations of non-esterified fatty acids (NEFA) and hepatic carnitine concentrations at 1 wk, 5 wk and 14 wk postpartum (<it>P </it>< 0.05).</p> <p>Conclusions</p> <p>The results of this study show for the first time that the expression of hepatic genes of carnitine synthesis and cellular uptake of carnitine is enhanced in dairy cows during early lactation. These changes might provide an explanation for increased hepatic carnitine concentrations observed in 1 wk postpartum and might be regarded as a physiologic means to provide liver cells with sufficient carnitine required for transport of excessive amounts of NEFA during a negative energy balance.</p
Cross-Sectional Analysis in the EPIC-Germany Study
Background Increased fibroblast growth factor 23 (FGF23), a bone-derived
hormone involved in the regulation of phosphate and vitamin D metabolism, has
been related to the development of cardiovascular disease (CVD) in chronic
kidney disease patients and in the general population. However, what
determines higher FGF23 levels is still unclear. Also, little is known about
the influence of diet on FGF23. The aim of this study was therefore to
identify demographic, clinical and dietary correlates of high FGF23
concentrations in the general population. Methods We performed a cross-
sectional analysis within a randomly selected subcohort of the European
Prospective Investigation into Cancer and Nutrition (EPIC)-Germany comprising
2134 middle-aged men and women. The Human FGF23 (C-Terminal) ELISA kit was
used to measure FGF23 in citrate plasma. Dietary data were obtained at
baseline via validated food frequency questionnaires including up to 148 food
items. Results Multivariable adjusted logistic regression showed that men had
a 66% lower and smokers a 64% higher probability of having higher FGF23 (≥ 90
RU/mL) levels compared, respectively, with women and nonsmokers. Each doubling
in parathyroid hormone, creatinine, and C-reactive protein was related to
higher FGF23. Among the dietary factors, each doubling in calcium and total
energy intake was related, respectively, to a 1.75 and to a 4.41 fold
increased probability of having higher FGF23. Finally, each doubling in the
intake of iron was related to an 82% lower probability of having higher FGF23
levels. Results did not substantially change after exclusion of participants
with lower kidney function. Conclusions In middle-aged men and women
traditional and non-traditional CVD risk factors were related to higher FGF23
concentrations. These findings may contribute to the understanding of the
potential mechanisms linking increased FGF23 to increased CVD risk
Nosema spp. infections cause no energetic stress in tolerant honeybees
Host-pathogen coevolution leads to reciprocal adaptations, allowing pathogens to increase
host exploitation or hosts to minimise costs of infection. As pathogen resistance is often
associated with considerable costs, tolerance may be an evolutionary alternative. Here, we
examined the effect of two closely related and highly host dependent intracellular gut
pathogens, Nosema apis and Nosema ceranae, on the energetic state in Nosema tolerant and
sensitive honeybees facing the infection. We quantified the three major haemolymph
carbohydrates fructose, glucose, and trehalose using high-performance liquid
chromatography (HPLC) as a measure for host energetic state. Trehalose levels in the
haemolymph were negatively associated with N. apis infection intensity and with N. ceranae
infection regardless of the infection intensity in sensitive honeybees. Nevertheless, there was
no such association in Nosema spp. infected tolerant honeybees. These findings suggest that
energy availability in tolerant honeybees was not compromised by the infection. This result
obtained at the individual level may also have implications at the colony level where workers
in spite of a Nosema infection can still perform as well as healthy bees, maintaining colony
efficiency and productivity.The Deutsche Forschungsgemeinschaft
DFG priority programme SPP 1399 ―Host-parasite co-evolution‖ (grant number MO373/26-
2).http://link.springer.com/journal/4362017-06-30hb2016Zoology and Entomolog
Vitamin D Receptor Deficiency and Low Vitamin D Diet Stimulate Aortic Calcification and Osteogenic Key Factor Expression in Mice
Low levels of 25-hydroxy vitamin D (25(OH)D) are associated with cardiovascular diseases. Herein, we tested the hypothesis that vitamin D deficiency could be a causal factor in atherosclerotic vascular changes and vascular calcification. Aortic root sections of vitamin D receptor knockout (VDR−/−) mice that were stained for vascular calcification and immunostained for osteoblastic differentiation factors showed more calcified areas and a higher expression of the osteogenic key factors Msx2, Bmp2, and Runx2 than the wild-type mice (P<0.01). Data from LDL receptor knockout (LDLR−/−) mice that were fed western diet with either low (50 IU/kg), recommended (1,000 IU/kg), or high (10,000 IU/kg) amounts of vitamin D3 over 16 weeks revealed increasing plasma concentrations of 25(OH)D (P<0.001) with increasing intake of vitamin D, whereas levels of calcium and phosphorus in plasma and femur were not influenced by the dietary treatment. Mice treated with the low vitamin D diet had more calcified lesions and a higher expression of Msx2, Bmp2, and Runx2 in aortic roots than mice fed recommended or high amounts of vitamin D (P<0.001). Taken together, these findings indicate vitamin D deficiency as a risk factor for aortic valve and aortic vessel calcification and a stimulator of osteogenic key factor expression in these vascular areas
Comparison of four mathematical models to analyze indicator-dilution curves in the coronary circulation
While several models have proven to result in accurate estimations when measuring cardiac output using indicator dilution, the mono-exponential model has primarily been chosen for deriving coronary blood/plasma volume. In this study, we compared four models to derive coronary plasma volume using indicator dilution; the mono-exponential, power-law, gamma-variate, and local density random walk (LDRW) model. In anesthetized goats (N = 14), we determined the distribution volume of high molecular weight (2,000 kDa) dextrans. A bolus injection (1.0 ml, 0.65 mg/ml) was given intracoronary and coronary venous blood samples were taken every 0.5–1.0 s; outflow curves were analyzed using the four aforementioned models. Measurements were done at baseline and during adenosine infusion. Absolute coronary plasma volume estimates varied by ~25% between models, while the relative volume increase during adenosine infusion was similar for all models. The gamma-variate, LDRW, and mono-exponential model resulted in volumes corresponding with literature, whereas the power-model seemed to overestimate the coronary plasma volume. The gamma-variate and LDRW model appear to be suitable alternative models to the mono-exponential model to analyze coronary indicator-dilution curves, particularly since these models are minimally influenced by outliers and do not depend on data of the descending slope of the curve only
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