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Possibilities of applying automated content analysis in journalism studies include, for example, machine learning to identify topics in journalistic coverage or measuring news diffusion via automated approaches. But how have computational methods been applied thus far? And what are consequences of the “computational turn” in communication science, especially concerning interdisciplinarity? Based on a systematic literature review, this article summarizes the use of automated content analysis in journalism studies. Results illustrate an increasing use of the method by communication scientists, as yet another indicator of methodological interdisciplinarity in communication science. However, there is little evidence of an increase in theoretical interdisciplinarity: Studies relying on computational methods do not increasingly refer to theories from other disciplines. With respect to practical interdisciplinarity, for instance collaborations, our discipline is by no means becoming more interdisciplinary. Instead, we find a shift in favor of technical disciplines. At least up to now, the “computational turn” in communication science should thus not be equated with an “interdisciplinary turn.”

Experimental studies of the magnetooptical and electrical transport properties of Fe/Cr/Fe magnetic trilayers show that a 2-monolayer (2-ML) oscillation period characterizes the magnetoresistance of the trilayers. Antiferromagnetic properties of the Cr interlayer are responsible for the periodicity. The magnetoresistance loops of the trilayers reveal specific steps that reflect the magnetic field values responsible for altering magnetization.

In conventional laparoscopy, the field of view of the surgeon is limited. Angled laparoscopes enable the observation of surrounding structures, however, to change the viewing perspective on a specific object, permanent repositioning and rotation of the shaft is required. In this paper, a demonstrator of a steerable flexible laparoscope is presented, enabling the user to intuitively adjust the perspective onto an object by means of a single control element. The laparoscope provides a viewing angle of ± 50° at 50 mm working distance. In first tests, the presented laparoscope showed advantages regarding intuitiveness of the control, easier handling, and improved depth perception.

During laparoscopic procedures, the surgeon's view of the situs, and thus her or his performance, is dependent on the skills of the camera assistant. The surgeon lacks control over his own field of view and there is a high potential for reducing mental load and workflow issues. In this paper, a research setup of a 360° laparoscopic imaging system is presented and evaluated. The system consists of a 360° camera and a head-mounted display, through which the surgeon can inspect the situs. In a user test, the system showed advantages over a conventional laparoscope regarding orientation in the situs, intuitiveness of operation, and faster task completion.

Byline: T. Lehnhauser, S. Ertem-Muller, M. Schafer, J. Janicka The present paper deals with the efficiency, accuracy, and robustness of numerical methods for computing turbulent flows on the basis of statistical turbulence models (RANS) and Large Eddy Simulation (LES). Various techniques concerning the discretisation and solution procedures which are helpful in improving the performance of such computations are presented. Corresponding capabilities are illustrated by considering representative test cases for RANS and LES computations.

Byline: B. Wegner, A. Kempf, C. Schneider, A. Sadiki, M. Schafer The method of large eddy simulation (LES) has a high potential to accurately predict complex turbulent flows. Gas turbine combustion systems feature a number of phenomena interacting with each other such as swirl with recirculation, complex turbulent mixing and combustion of premixed, non-premixed as well as partially premixed nature. We therefore tend to approach the simulation of real gas turbine combustors step by step. The aim of this paper is to document some of the progress made at EKT in assessing the capability of LES in flows separately exhibiting distinct features of gas turbine combustors. Some results from two configurations are presented and discussed: a non-confined isothermal swirl flow with precessing vortex core and a non-premixed bluff-body flame.

Accurate measurement of interaction forces during robot-assisted surgery requires compact force sensing modalities in the surgical tools, thus might add considerable cost to the setup. Measuring the motor current to estimate gripping forces, is an advantageous approach since no expensive force sensor is needed. In this paper, a mechanical interface is presented, which allows actuating conventional articulated instruments for robot-assisted surgery. The interface features the estimation of static gripping forces at the instrument’s tip based on the motor current. The evaluation shows reproducible results, and the current-based approach seems to be a cost-efficient way to estimate gripping forces.

Schafer, M., D. Bahde, B. Bosche, Y. Ladilov, C. Schafer, H. M. Piper, and T. Noll. Modulation of early [[Ca.sup.2+]].sub.i] rise in metabolically inhibited endothelial cells by xestospongin C. Am J Physiol Heart Circ Physiol 280: H1002-H1010, 2001.--When energy metabolism is disrupted, endothelial cells lose [Ca.sup.2+] from endoplasmic reticulum (ER) and the cytosolic [Ca.sup.2+] concentration ([[Ca.sup.2+]].sub.i]) increases. The importance of glycolytic energy production and the mechanism of [Ca.sup.2+] loss from the ER were analyzed. Endothelial cells from porcine aorta in culture and in situ were used as models. 2-Deoxy-D-glucose (2-DG, 10 mM), an inhibitor of glycolysis, caused an increase in [[Ca.sup.2+]].sub.i] (measured with fura 2) within 1 min when total cellular ATP contents were not yet affected. Stimulation of oxidative energy production with pyruvate (5 mM) did not attenuate this 2-DG-induced rise of [[Ca.sup.2+]].sub.i], while this maneuver preserved cellular ATP contents. The inhibitor of ER-[Ca.sup.2+]-ATPase, thapsigargin (10 nM), augmented the 2-DG-induced rise of [[Ca.sup.2+]].sub.i]. Xestospongin C (3 [micro]M), an inhibitor of D-myo-inositol 3-phosphate [Ins(3)P]-sensitive ER-[Ca.sup.2+] release, abolished the rise. The results demonstrate that the ER of endothelial cells is very sensitive to glycolytic metabolic inhibition. When this occurs, the ER [Ca.sup.2+] store is discharged by opening of the Ins(3)P-sensitive release channel. Xestospongin C can effectively suppress the early [[Ca.sup.2+]].sub.i] rise in metabolically inhibited endothelial cells. D-myo-inositol 3-phosphate-sensitive [Ca.sup.2+] release; ischemia; hypoxia; cytosolic [Ca.sup.2+] concentration

When a structural element, like a column, is evaluated for resistance using the finite element method or analytical calculation, all parameters related to the resistance side and action effect are treated as deterministic. Nevertheless, in probabilistic analyses, these parameters are regarded as random variables, which are defined using various distributions like the normal distribution, log-normal distribution, beta, or gamma distribution. Monte Carlo Simulation (MCS) and Latin Hypercube Sampling (LHS) are two sampling methods widely used for generating random samples from statistical distribution. The number of samples generated influences the accuracy of the sampling methods especially the Monte Carlo Simulation; generally speaking, the more samples generated, the more accurate the results and this also implies a significant amount of work and computation time. Consequently, the purpose of this paper is to compare the two sampling methods for the reliability assessment of the resistance of the composite column to flexural buckling under compression force.

Schafer, C., Y. V. Ladilov, M. Schafer, and H. M. Piper. Inhibition of NHE protects reoxygenated cardiomyocytes independently of anoxic [Ca.sup.2+] overload and acidosis. Am J Physiol Heart Circ Physiol 279: H2143-H2150, 2000.--We investigated the question of whether inhibition of the [Na.sup.+]/[H.sup.+] exchanger (NHE) during ischemia is protective due to reduction of cytosolic [Ca.sup.2+] accumulation or enhanced acidosis in cardiomyocytes. Additionally, the role of the [Na.sup.+]-[MATHEMATHICAL EXPRESSION] symporter (NBS) was investigated. Adult rat cardiomyocytes were exposed to simulated ischemia and reoxygenation. Cytosolic pH [2',7'-bis(2-carboxyethyl)-5(6)-carboxyfluorescein (BCECF)], [Ca.sup.2+] (fura 2), [Na.sup.+] [sodium-binding benzolfuran isophthatlate (SBFI)], and cell length were measured. NHE was inhibited with 3 [Mu]mol/l HOE 642 or 1 [Mu]mol/l 5-(N-ethyl-N-isopropyl)-amiloride (EIPA), and NBS was inhibited with HEPES buffer. During anoxia in bicarbonate buffer, cells developed acidosis and intracellular Na and Ca ([Na.sub.i] and [Ca.sub.i], respectively) overload. During reoxygenation cells underwent hypercontracture (44.0 [+ or -] 4.1% of the preanoxic length). During anoxia in bicarbonate buffer, inhibition of NHE had no effect on changes in intracellular pH ([pH.sub.i]), [Na.sub.i], and [Ca.sub.i], but it significantly reduced the reoxygenation-induced hypercontracture (HOE: 61.0 [+ or -] 1.4%, EIPA: 68.2 [+ or -] 1.8%). The sole inhibition of NBS during anoxia was not protective. We conclude that inhibition of NHE during anoxia protects cardiomyocytes against reoxygenation injury independently of cytosolic acidification and [Ca.sub.i] overload. hypercontracture; pH control; calcium; sodium-hydrogen exchanger

ATP induces dephosphorylation of myosin light chain in endothelial cells. Am J Physiol Cell Physiol 279: C717-C723, 2000.--In cultured porcine aortic endothelial monolayers, the effect of ATP on myosin light chain (MLC) phosphorylation, which controls the endothelial contractile machinery, was studied. ATP (10 [micro]M) reduced MLC phosphorylation but increased cytosolic [Ca.sup.2+] concentration ([[[Ca.sup.2+]].sub.i]). Inhibition of the ATP-evoked [[[Ca.sup.2+]].sub.i] rise by xestospongin C (10 [micro]M), an inhibitor of the inositol trisphosphate-dependent [Ca.sup.2+] release from endoplasmic reticulum, did not affect the ATP-induced dephosphorylation of MLC. MLC dephosphorylation was prevented in the presence of calyculin A (10 nM), an inhibitor of protein phosphatases PP-1 and PP-2A. Thus ATP activates MLC dephosphorylation in a [Ca.sup.2+]-independent manner. In the presence of calyculin A, MLC phosphorylation was incremented after addition of ATP, an effect that could be abolished when cells were loaded with the [Ca.sup.2+] chelator 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid acetoxymethyl ester (10 [micro]M). Thus ATP also activates a [Ca.sup.2+]-dependent kinase acting on MLC. In summary, ATP simultaneously stimulates a functional antagonism toward both phosphorylation and dephosphorylation of MLC in which the dephosphorylation prevails. In endothelial cells, ATP is the first physiological mediator identified to activate MLC dephosphorylation by a [Ca.sup.2+]-independent mechanism. adenosine 5'-triphosphate; myosin light chain phosphorylation; protein phosphatases