A performance- and energy-oriented extended tuning process for time-step-based scientific applications

The Journal of Supercomputing - Scientific application codes are often long-running time- and energy-consuming parallel codes, and the tuning of these methods towards the characteristics of a...     

Oxygen permeation of various archetypes of oxygen membranes based on BSCF

Ba_0.5Sr_0.5Co_0.8Fe_0.2O_3‐δ tubes, capillaries, capillary modules, and asymmetric membranes were prepared and tested for oxygen permeation in a dead‐end vacuum operation mode at temperatures up to 850^°C. The capillary module was built up by reactive air brazing using seven capillaries and a supply tube. Two machined discs were used as an end cap and as a connector plate. The oxygen permeation behaves according to Wagner at small driving forces, but significant negative deviations were observed for asymmetric membranes and single capillaries at higher ones. This is caused by pressure drops at the vacuum side for single capillaries. The highest oxygen flux was revealed for the capillary module with 175.5 mL(STP)/min at a low‐vacuum pressure of 0.042 bar at 850^°C, but the asymmetric membrane showing a little bit higher flux at moderate vacuum pressures above 0.07 bar. © 2012 American Institute of Chemical Engineers AIChE J, 58: 3195–3202, 2012     

Analysis of microRNAs in Exosomes of Breast Cancer Patients in Search of Molecular Prognostic Factors in Brain Metastases

Brain metastases are the most severe tumorous spread during breast cancer disease. They are associated with a limited quality of life and a very poor overall survival. A subtype of extracellular vesicles, exosomes, are sequestered by all kinds of cells, including tumor cells, and play a role in cell-cell communication. Exosomes contain, among others, microRNAs (miRs). Exosomes can be taken up by other cells in the body, and their active molecules can affect the cellular process in target cells. Tumor-secreted exosomes can affect the integrity of the blood-brain barrier (BBB) and have an impact on brain metastases forming. Serum samples from healthy donors, breast cancer patients with primary tumors, or with brain, bone, or visceral metastases were used to isolate exosomes and exosomal miRs. Exosomes expressed exosomal markers CD63 and CD9, and their amount did not vary significantly between groups, as shown by Western blot and ELISA. The selected 48 miRs were detected using real-time PCR. Area under the receiver-operating characteristic curve (AUC) was used to evaluate the diagnostic accuracy. We identified two miRs with the potential to serve as prognostic markers for brain metastases. Hsa-miR-576-3p was significantly upregulated, and hsa-miR-130a-3p was significantly downregulated in exosomes from breast cancer patients with cerebral metastases with AUC: 0.705 and 0.699, respectively. Furthermore, correlation of miR levels with tumor markers revealed that hsa-miR-340-5p levels were significantly correlated with the percentage of Ki67-positive tumor cells, while hsa-miR-342-3p levels were inversely correlated with tumor staging. Analysis of the expression levels of miRs in serum exosomes from breast cancer patients has the potential to identify new, non-invasive, blood-borne prognostic molecular markers to predict the potential for brain metastasis in breast cancer. Additional functional analyzes and careful validation of the identified markers are required before their potential future diagnostic use.     

Entwicklung und Anwendung von mathematischen Optimierungsmethoden zur Ableitung von vereinfachten Prüfungen für Fahrwerksbauteile

Testing the fatigue life time of chassis components is necessary during the development process and for quality supervision during the period of series production. In many cases a simplified test is done to reduce the complexity of the test. The development engineer has to develop the specification of those simplified tests. According to the task different approaches are possible: Looking for an adaquate test load or for a simplified mounting ore both. This paper deals with several numerical methods for test specification development. Especially a numerical optimization routine is presented for detection of a signifcant load case. Also the iterative searching for a simplified mounting in combination with damage based selection of load channel is shown. Exemplary the application of the routines is demonstrated by Porsche PANAMERA wheel carrier and a suspension‐strut receiving. The actual stage of development of the numerical routines is presented. In addition intended upgrades of the software are shown.     

Playing chess unconsciously.

Expertise in a certain stimulus domain enhances perceptual capabilities. In the present article, the authors investigate whether expertise improves perceptual processing to an extent that allows complex visual stimuli to bias behavior unconsciously. Expert chess players judged whether a target chess configuration entailed a checking configuration. These displays were preceded by masked prime configurations that either represented a checking or a nonchecking configuration. Chess experts, but not novice chess players, revealed a subliminal response priming effect, that is, faster responding when prime and target displays were congruent (both checking or both nonchecking) rather than incongruent. Priming generalized to displays that were not used as targets, ruling out simple repetition priming effects. Thus, chess experts were able to judge unconsciously presented chess configurations as checking or nonchecking. A 2nd experiment demonstrated that experts' priming does not occur for simpler but uncommon chess configurations. The authors conclude that long-term practice prompts the acquisition of visual memories of chess configurations with integrated form-location conjunctions. These perceptual chunks enable complex visual processing outside of conscious awareness. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Design and synthesis of 3D ordered macroporous ZrO2/Zeolite nanocomposites

Zeolite NaY nanocrystals (20−50 nm) were hydrothermally grown on polyelectrolyte-coated three-dimensionally ordered macroporous (3DOM) activated zirconia. The zeolite nanocrystallites uniformly coated the macropore walls of 3DOM sulfated zirconia, but sulfate groups were lost during the hydrothermal reaction. 3DOM tungstated zirconia was found to be more stable in the strong basic environment of the zeolite precursor solution. Further, ion-exchange of zeolite NaY with ruthenium followed by hydrogen-reduction formed a composite of RuNaY and 3DOM activated zirconia. The presence of ruthenium was confirmed by X-ray photoelectron spectroscopy and the external shape of zeolite nanoparticles was maintained after ion-exchange, but the zeolite lattice fringes could not be observed by transmission electron microscopy after incorporation of reduced ruthenium. Although the catalytic activity of the materials has not yet been tested, these hierarchical nano- and microstructures bring multiple catalyst components (modified zeolite Y, a typical Fischer–Tropsch catalyst, and activated zirconia, an isomerization catalyst) together in intimate contact for potential multi-reaction processes.     

Assessment of follicular development in cryopreserved primate ovarian tissue by xenografting: prepubertal tissues are less sensitive to the choice of cryoprotectant

Improvements in cancer survival rates have renewed interest in the cryopreservation of ovarian tissue for fertility preservation. We used the marmoset as a non-human primate model to assess the effect of different cryoprotectives on follicular viability of prepubertal compared to adult ovarian tissue following xenografting. Cryopreservation was performed with dimethylsulfoxide (DMSO), 1,2-propanediol (PrOH), or ethylene glycol (EG) using a slow freezing protocol. Subsequently, nude mice received eight grafts per animal from the DMSO and the PrOH groups for a 4-week grafting period. Fresh, cryopreserved-thawed, and xenografted tissues were serially sectioned and evaluated for the number and morphology of follicles. In adult tissue, the percentage of morphologically normal primordial follicles significantly decreased from 41.2 ± 4.5% (fresh) to 13.6 ± 1.8 (DMSO), 9.5 ± 1.7 (PrOH), or 6.8 ± 1.0 (EG) following cryopreservation. After xenografting, the percentage of morphologically normal primordial (26.2 ± 2.5%) and primary follicles (28.1 ± 5.4%) in the DMSO group was significantly higher than that in the PrOH group (12.2 ± 3 and 5.4 ± 2.1% respectively). Proliferating cell nuclear antigen (PCNA) staining suggests the resumption of proliferative activity in all cellular compartments. In prepubertal tissues, primordial but not primary follicles display a similar sensitivity to cryopreservation, and no significant differences between DMSO and PrOH following xenografting were observed. In conclusion, DMSO shows a superior protective effect on follicular morphology compared with PrOH and EG in cryopreserved tissues. Xenografting has confirmed better efficacy of DMSO versus PrOH in adult but not in prepubertal tissues, probably owing to a greater capacity of younger animals to compensate for cryoinjury.     

Orthoamide. L. Beiträge zur Chemie von Propiolaldehydaminalen – Synthesen und Umsetzungen zu Push–Pull-substituierten Buta-1,3-dienen,Cyclobutanen sowie vinylogen Amidiniumsalzen und 1,2,3-Triazolen

Orthoamides. L. Contribution to the Chemistry of Propiolaldehydaminales – Synthesis and Transformations to Push–Pull-substituted Buta-1,3-dienes, Cyclobutanes, Vinylogous Amidinium Salts and 1,2,3-Triazoles Tert-butylaminalester 5 reacts with terminal alkynes to give aminals of substituted propiolaldehydes 3c, d . The aminal 3a is accessible from N,N,N′,N′-tetramethylformamidinium chloride (7b) and sodium acetylide. The aminals 3b,c can also be prepared from bis(dimethylamino)acetonitrile 8 and terminal alkynes in the presence of sodium hydride. The nitrile 8 is also useful for the preparation of the bis-aminal of acetylenedialdehyde 6 . The aminal 3e can be transaminated by heating with secondary amines to give the aminals 3f–i . The aminals 3a–i react with strong CH₂-acidic compounds (pK_a between 9 and 14) to give the 1-dialkylamino-1,3-butadienes 10 . The isomeric 1-dialkylamino-butadienes 18 can be obtained from the condensation of the CH-acidic cinnamic acid derivatives 19 with dimethylformamidedimethylacetal. CH and NH-acidic compounds as cyanacetamide react with the aminals 3c,e exclusively with the acidic methylene group to produce the enamines 10h,t . The acylformamidine 21 can be obtained from 10t and tert-butylaminalester 5 . The pyridone 22 is accessible from the condensation product 10h by thermal cyclization. The pyrido[2,3-d]pyrimidine 26 is formed in the reaction of the 6-amino-uracile 23 with the aminal 3a . In an unexpected reaction the 1,2-bis(cyano-dialkylaminomethylene)-cyclobutanes 28a–d result from the action of trimethylsilylcyanide on the aminals 3e–h . The corresponding reaction with trimethylsilylisothiocyanate affords the vinylogous amidinium thiocyanates 34a, b . In the reaction of trimethylsilylazide and the aminals 3 are produced the 4-(dialkylaminomethylene)-4H-1,2,3-triazoles 38 .     

Approximated matrix decomposition for IMRT planning with multileaf collimators

A standard problem in intensity modulated radiation therapy is the representation of a given intensity matrix, i.e. a matrix of nonnegative integers, as a nonnegative linear combination of special 0-1-matrices, called segments. These segments can be practically realized by multileaf collimators. One important aim is the minimization of the sum of the coefficients of the linear combination, i.e. the delivery time. In this article, we study the question how much the delivery time can be reduced if some small deviation from the given intensity matrix is allowed. We characterize the optimal solutions for one-row matrices and show that the approximation can be carried out in an iterative way. The structural characterization yields a fast algorithm that minimizes the delivery time and then also the deviation. Moreover, algorithms for the general case together with numerical results are presented.