Ab Initio Molecular Dynamics with Born-Oppenheimer and Extended Lagrangian Methods Using Atom Centered Basis Functions

Schlegel, H. Bernhard Korean Chemical Society 2003 Bulletin of the Korean Chemical Society Vol.24 No.6

In ab initio molecular dynamics, whenever information about the potential energy surface is needed for integrating the equations of motion, it is computed “on the fly” using electronic structure calculations. For Born-Oppenheimer methods, the electronic structure calculations are converged, whereas in the extended Lagrangian approach the electronic structure is propagated along with the nuclei. Some recent advances for both approaches are discussed.

Fifty Years of Nitrogen and Phosphorus Fertilization on Soil Properties and Production of Irrigated Continuous Corn in the USA

Alan Schlegel,John Havlin 한국토양비료학회 2014 한국토양비료학회 학술발표회 초록집 Vol.2014 No.6

Effects of Benzoic Acid and Dietary Calcium:Phosphorus Ratio on Performance and Mineral Metabolism of Weanling Pigs

Gutzwiller, A.,Schlegel, P.,Guggisberg, D.,Stoll, P. Asian Australasian Association of Animal Productio 2014 Animal Bioscience Vol.27 No.4

In a $2{\times}2$ factorial experiment the hypotheses tested were that the metabolic acid load caused by benzoic acid (BA) added to the feed affects bone mineralization of weanling pigs, and that a wide dietary calcium (Ca) to phosphorus (P) ratio in phytase-supplemented feeds with a marginal P concentration has a positive effect on bone mineralization. The four experimental diets, which contained 0.4% P and were supplemented with 1,000 FTU phytase/kg, contained either 5 g BA/kg or no BA and either 0.77% Ca or 0.57% Ca. The 68 four-week-old Large White pigs were fed the experimental diets ad libitum for six weeks and were then slaughtered. Benzoic acid increased feed intake (p = 0.009) and growth rate (p = 0.051), but did not influence the feed conversion ratio (p>0.10). Benzoic acid decreased the pH of the urine (p = 0.031), but did not affect breaking strength and mineralization of the tibia (p>0.10). The wide Ca:P ratio decreased feed intake (p = 0.034) and growth rate (p = 0.007) and impaired feed the conversion ratio (p = 0.027), but increased the mineral concentration in the fat-free DM of the tibia (p = 0.013) without influencing its breaking strength (p>0.10). The observed positive effect of the wide Ca:P ratio on bone mineralization may be attributed, at least in part, to the impaired feed conversion ratio, i.e. to the higher feed intake and consequently to the higher mineral intake per kg BW gain. The negative impact on animal performance of the wide dietary Ca:P ratio outweighs its potentially positive effect on bone mineralization, precluding its implementation under practical feeding conditions.

Modulation of cartilage differentiation by melanoma inhibiting activity/cartilage-derived retinoic acid-sensitive protein (MIA/CD-RAP)

Thomas Schubert,Jacqueline Schlegel,Rainer Schmid,Susanne Grässel,Anja-Katrin Bosserhoff,Alfred Opolka,Martin Humphries 생화학분자생물학회 2010 Experimental and molecular medicine Vol.42 No.3

Melanoma inhibiting activity/cartilage-derived retinoic acid-sensitive protein (MIA/CD-RAP) is a small soluble protein secreted from malignant melanoma cells and from chondrocytes. Recently, we revealed that MIA/CD-RAP can modulate bone morphogenetic protein (BMP)2-induced osteogenic differentiation into a chondrogenic direction. In the current study we aimed to find the molecular details of this MIA/CD-RAP function. Direct influence of MIA on BMP2 by protein-protein-interaction or modulating SMAD signaling was ruled out experimentally. Instead, we revealed inhibition of ERK signaling by MIA/CD-RAP. This inhibition is regulated via binding of MIA/CD-RAP to integrin α5 and abolishing its activity. Active ERK signaling is known to block chondrogenic differentiation and we revealed induction of aggrecan expression in chondrocytes by treatment with MIA/CD-RAP or PD098059,an ERK inhibitor. In in vivo models we could support the role of MIA/CD-RAP in influencing osteogenic differentiation negatively. Further, MIA/CD-RAP-deficient mice revealed an enhanced calcified cartilage layer of the articular cartilage of the knee joint and disordered arrangement of chondrocytes. Taken together,our data indicate that MIA/CD-RAP stabilizes cartilage differentiation and inhibits differentiation into bone potentially by regulating signaling processes during differentiation.

THE BARYON OSCILLATION SPECTROSCOPIC SURVEY OF SDSS-III

Dawson, Kyle S.,Schlegel, David J.,Ahn, Christopher P.,Anderson, Scott F.,Aubourg, É,ric,Bailey, Stephen,Barkhouser, Robert H.,Bautista, Julian E.,Beifiori, Alessandra,Berlind, Andreas A.,Bhardw IOP Publishing 2013 The Astronomical journal Vol.145 No.1

Mouse fMRI under ketamine and xylazine anesthesia: Robust contralateral somatosensory cortex activation in response to forepaw stimulation

Shim, Hyun-Ji,Jung, Won Beom,Schlegel, Felix,Lee, Joonsung,Kim, Sangwoo,Lee, Jungryun,Kim, Seong-Gi Elsevier 2018 NeuroImage Vol.177 No.-

<P><B>Abstract</B></P> <P>Mouse fMRI is critically useful to investigate functions of mouse models. Until now, the somatosensory-evoked responses in anesthetized mice are often widespread and inconsistent across reports. Here, we adopted a ketamine and xylazine mixture for mouse fMRI, which is relatively new anesthetics in fMRI experiments. Forepaw stimulation frequency was optimized using cerebral blood volume (CBV)-weighted optical imaging (n = 11) and blood-oxygenation-level dependent (BOLD) fMRI with a gradient-echo time of 16 ms at 9.4 T, and 4 Hz stimulation with 0.5 ms and 0.5 mA pulses induced the highest hemodynamic response. For 20-s 4-Hz unilateral forepaw stimulation, localized BOLD activity was consistently found in the contralateral primary forelimb somatosensory cortex (S1FL), while no significant change was observed in the ipsilateral S1FL. The mean magnitude was 1.44 ± 0.20% SEM (n = 9) in the contralateral S1FL and 0.69 ± 0.10% in the contralateral thalamus. The variability of evoked fMRI responses across sessions was investigated by comparing with resting state fMRI (rsfMRI) functional connectivity (FC). Evoked responses in S1FL were correlated positively with rsfMRI FC between bilateral S1FL (r = 0.63 to 0.69) and negatively with FC between S1FL and the anterior cingulate cortex (r = −0.50 to −0.57), suggesting that rsfMRI FC is a good index of the evoked fMRI response and anesthetized animal condition. Finally, three weekly fMRI scans were performed in 5 mice, and localized activity was reproducibly observed in S1FL, with a success rate of 70–95%. In summary, our developed fMRI protocol can be used for mapping functions of mouse models.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Bilateral BOLD response induced by forepaw stimulation is observed under isoflurane. </LI> <LI> Ketamine and xylazine anesthesia is used for mouse fMRI. </LI> <LI> Forepaw stimulation of 4 Hz evokes the highest hemodynamic response. </LI> <LI> BOLD activation is reproducibly localized at the contralateral somatosensory cortex. </LI> <LI> Resting-state functional connectivity predicts evoked fMRI responses. </LI> </UL> </P>

Bladder Augmentation Using Lyoplant®: First Experimental Results in Rats

F. Winde,K. Backhaus,J. A. Zeitler,N. Schlegel,Th. Meyer 한국조직공학과 재생의학회 2019 조직공학과 재생의학 Vol.16 No.6

BACKGROUND: Congenital defects of the urinary bladder (micro- or contracted bladder, bladder exstrophy) remain a challenging problem for pediatric surgeons. Even when conservative treatment options are fully exhausted, irreversible renal dysfunction can be observed in a large number of cases that can even lead to chronic renal failure and the need for kidney transplantation. To protect kidney function bladder augmentation using intestinal tissue is commonly applied as the standard treatment method. However due to the unphysiological nature of intestinal tissue a number of problems and complications such as urinary tract infections or bladder stone formation limit the clinical success of this approach. Moreover a number of substitutes for the implementation of a bladder augmentation have been tested without success to date. Here we used an experimental model to test wether the biocompatible collagen mesh Lyoplant may be a suitable candidate for bladder augmentation. METHODS: We implanted a biocompatible collagen mesh (Lyoplant) in a bladder defect rat model for bladder augmentation (Lyoplant-group: n = 12; sham group n = 4). After 6 weeks the abdomen was reopened and the initial implant as well as the bladder were resected for histological and immunohistochemical examination. RESULTS: All but one rat exhibited physiological growth and behaviour after the operation without differences between the Lyoplant-group (n = 12) and the sham group (n = 3). One rat from the sham group had to be excluded because of a suture leakage. No wound healing complications, wound infections and no herniation were observed. After 5 weeks the implants showed an adequate incorporation in all cases. This was confirmed by immunohistological analyses where a significant cell infiltration and neovascularization was observed. CONCLUSION: In summary, Lyoplant appears to be a promising tool in experimental bladder augmentation/regeneration in rats.

Light-cone divergence in twist-3 correlation functions

Gamberg, L.P.,Hwang, D.S.,Metz, A.,Schlegel, M. Elsevier 2006 Physics letters: B Vol.639 No.5

<P><B>Abstract</B></P><P>It is argued that the definition of the twist-3 transverse momentum dependent correlation functions must be modified if they contain light-like Wilson lines. In the framework of a simple spectator model of the nucleon we show explicitly the presence of a light-cone divergence for a specific twist-3 time-reversal odd parton density. This divergence emerges for all eight twist-3 T-odd correlators and appears also in the case of a quark target in perturbative QCD. The divergence can be removed by using non-light-like Wilson lines. Based on our results we argue that currently there exists no established factorization formula for transverse momentum dependent twist-3 observables in semi-inclusive DIS and related processes.</P>

Comparison of Bioavailability of Organic Selenium Sources in Finishing Pigs

Jang, Y.D.,Choi, H.B.,Durosoy, S.,Schlegel, P.,Choi, B.R.,Kim, Y.Y. Asian Australasian Association of Animal Productio 2010 Animal Bioscience Vol.23 No.7

This experiment was conducted to evaluate the bioavailability of different organic selenium (Se) products in finishing pigs. A total of 48 growing pigs, average body weight $47.6kg{\pm}0.05$, were allotted to four different treatments in a randomized complete block (RCB) design in three replicates with four pigs per pen. Three different organic Se products, Se-enriched yeast (treatments A and B) and Se-proteinate (treatment C), were used in conjunction with a basal diet with no added Se as a control treatment. In growing period, pigs were fed the same diet but finishing pigs were fed each treatment diet containing organic Se products for 6 weeks. During the experimental period, feed intake and body weight were measured and blood samples were collected to determine the Se concentration. At the end of this experiment, 3 pigs per treatment were killed and various tissues (loin, liver, kidney, pancreas and spleen) were collected to analyze the Se concentration. The body weight, and average daily feed intake (ADFI) were similar among treatments, but the average daily gain (ADG) was increased on Se-proteinate treatment (p<0.01) and gain-to-feed ratio (G/F ratio) was improved on Se yeast B or Se-proteinate treatment (p<0.01). The tissue Se content was also increased when pigs were fed organic Se sources, and Se was retained efficiently in loin (p<0.01) and kidney (p<0.05) when Se yeast B was provided. The serum Se concentration was increased when organic Se was provided and was higher when pigs were fed Se-proteinate (p<0.01); subsequently liver Se was also higher on Se-proteinate treatment than other treatments. The Se yeast A treatment did not show any increment of Se concentration both in serum and tissues. This result demonstrated that Se retention and bioavailability in finishing pigs were varied by Se products although organic sources were provided. Consequently, each organic Se product should be evaluated before it is used as a supplement in animal feed.

Constraining primordial non-Gaussianity with the 3-point correlation function of the SDSS-IV eBOSS DR14 quasar sample

Peter D. Choi,Graziano Rossi,Zachary Slepian,Daniel Eisenstein,Shirley Ho,David Schlegel 한국천문학회 2017 天文學會報 Vol.42 No.1