The inferior caval vein draining into the left atrial cavity : a rare case

The inferior vena cava (IVC) draining into the left atrium (LA) is exceedingly rare in the setting of the usual atrial arrangement (situs solitus). This article describes a patient with this unique anomaly, and its repair.peer-reviewe

Performance of conventionally powered vehicles tested to an electric vehicle test procedure

A conventional Volkswagen transporter, a Renault 5, a Pacer, and a U. S. Postal Service general DJ-5 delivery van were treated to an electric vehicle test procedure in order to allow direct comparison of conventional and electric vehicles. Performance test results for the four vehicles are presented

Optimization of cascaded regenerative links based on phase sensitive amplifiers

We develop an analytical method for optimizing phase sensitive amplifiers for regeneration in multilevel phase encoded transmission systems. The model accurately predicts the optimum transfer function characteristics and identifies operating tolerances for different signal constellations and transmission scenarios. The results demonstrate the scalability of the scheme and show the significance of having simultaneous optimization of the transfer function and the signal alphabet. The model is general and can be applied to any regenerative system

Idiopatski i sekundarni stečeni megakolon kod pasa udruženi su sa smanjenom vip-inervacijom u oštećenom kolonu

It is well established that megacolon in carnivores, including both cats and dogs, is a common finding. Megacolon occurs more often in the cat that the dog. Based on current data idiopathic megacolon is a common cause of constipation in cats (62% of constipated cats are affected by diopathic megacolon). There is no evidence of idiopathic megacolon in dogs and publications about this disease in this species is very scarce. We investigated the enteric nervous system in the dilated portion (DP) of the colon in dogs with idiopathic aquired (n=7) or secondary aquired megacolon (n=21) and compared the results with a normal colon in control dogs (n=3). Colonic sections of surgical specimens were investigated by conventional and immunohistochemical methods, including pan-neuronal markers (NSE, synaptophisin, and neurofilament) and VIP, as well as S-100 protein for detection of ganglionic glial cells. Compared to controls, the two megacolon groups showed no changes of density of enteric neurons in both submucosal and myenteric nervous plexuses in DP of the colon and of enteric glial cells. However, compared to controls and dogs with secondary megacolon, there was a significant decrease in the density of NFP-ir nerve fibers in the longitudinal muscle layer in dogs with idiopathic acquired megacolon. In addition, dogs with idiopathic megacolon display decreased VIP-ir in the myenteric plexus and lamina propria mucosae, and absence of VIP-ir neurons in the submucosal plexus of DP of the colon. Similar alterations, although of lesser severity, may be found in dogs with secondary aquired megacolon. We consider that both idiopathic and secondary aquired megacolon might occur on the basis of a dysplastic changes of VIP-ir enteric neurons.Poznato je da se magakolon javlja kod mesojeda, uključujući mačke i pse, pri čemu je ovo oboljenje daleko učestalije kod mačaka. Na osnovu dosadašnjih saznanja, idiopatski megakolon je čest uzročnik konstipacije kod mačaka i 62% mačaka sa konstipacijom ima idiopatski megakolon. Istovremeno, podaci o psima sa idiopatskim megakolonom veoma su oskudni. U ovom radu je proučavan enterični nervni sistem u dilatiranom delu kolona kod 7 pasa sa idiopatskim megakolonom i 21 psa sa sekundarnim stečenim megakolonom, a rezultati su upoređeni sa normalnim kolonom kod 3 kontrolne zdrave životinje. Tkivni preseci kolona bojeni su klasičnim histološkim i imunohistohemijskim metodama, pri čemu su primenjeni pan-neuronski markeri (NSE, sinaptofizin i neurofilament) i VIP, kao i S-100 protein za detekciju glijalnih ćelija u enteričnim ganglijama. Nisu otkrivene razlike u gustini enteričnih neurona u submukoznom i mijenteričnom pleksusu kod životinja sa megakolonom, kao ni razlike u gustini glijalnih ćelija enteričnih ganglija, u odnosu na kontrolnu grupu životinja. Međutim, u odnosu na kontrolnu grupu, kod životinja sa idiopatskim megakolonom dokazana je smanjena VIP-imunoreaktivnost (ir) u mienteričnom pleksusu i krznu mukoze, kao i kompletno odsustvo VIP-ir neurona u submukoznom pleksusu dilatiranog dela kolona. Slične promene, ali u manjem stepenu, postojale su kod pasa sa sekundarnim stečenim megakolonom. Može da se zaključi da u patogenezi idiopatskog i sekundarnog stečenog megakolona značajnu ulogu imaju displastične promene u VIP-ergičkim neuronima enteričkog nervnog sistema

Artificial Neural Network Based Analysis of High Throughput Screening Data for Improved Prediction of Active Compounds

Artificial Neural Networks (ANNs) are trained using High Throughput Screening (HTS) data to recover active compounds from a large data set. Improved classification performance was obtained on combining predictions made by multiple ANNs. The HTS data, acquired from a Methionine Aminopeptidases Inhibition study, consisted of a library of 43,347 compounds, and the ratio of active to non-active compounds, RA/N, was 0.0321. Back-propagation ANNs were trained and validated using Principal Components derived from the physico-chemical features of the compounds. On selecting the training parameters carefully, an ANN recovers one-third of all active compounds from the validation set with a three-fold gain in RA/N value. Further gains in RA/N values were obtained upon combining the predictions made by a number of ANNs. The generalization property of the back-propagation ANNs was utilized to train those ANNs with the same training samples, after being initialized with different sets of random weights. As a result, only 10% of all available compounds were needed for training and validation, and the rest of the data set was screened with more than a ten-fold gain of the original RA/N value. Thus, ANNs trained with limited HTS data might become useful in recovering active compounds from large data sets

Ecology, behaviour and management of the European catfish

The extreme body sizes of ‘megafishes’ associated with their high commercial values and recreational interests have made them highly threatened in their native range worldwide by human-induced impacts such as overexploitation. Meanwhile, and because of the aforementioned interests, some megafishes have been introduced outside of their native range. A notable exampled is the European catfish (Silurus glanis), one of the few siluriforms native from western Europe and among the 10 largest freshwater fish worldwide, attaining a total length over 2.7 m and a documented mass of 130 kg. Its distinct phylogeny and extreme size imply many features rare among other European fish such as peculiar behaviours (massive aggregations, beaching), consumption of large bodied prey, fast growth rate, long lifespan, high fecundity, nest guarding and large eggs. The spread of the species is likely to continue due to illegal introduction coupled with natural range extension due to current and future climate change. Based on these attributes and potential future risks, this introduced giant predator in European fresh waters could provide a novel model species of high utility for testing aspects of ecological and invasion theory and associated hypotheses. Here, we reviewed the most recent knowledge on the current distribution and the ecology of the species to understand how this can help advance our understanding of biological invasions. We also identified key research questions that should help stimulating new research on this intriguing, yet largely unknown, species and, more generally, on the ecology of invasive species

Effects of stator and rotor core ovality on induction machine behavior

Asymmetries in the air gap of induction motors produce additional harmonics in the flux density and force waves. A complete transient finite element model analyzes the harmonics produced from two possible asymmetries, a stator core ovality and a rotor ovality. The analysis of the air gap flux density and magnetic force waves determined by the finite element model shows unique harmonic frequencies due to the ovality of the air gap

Homodyne OFDM with Optical Injection Locking for Carrier Recovery

Homodyne detection provides the simplest digital signal processing (DSP) solution to optical coherent detection and minimizes the receiver bandwidth requirements. These features make it promising for high spectrally-efficient formats such as Optical Orthogonal Frequency Domain Multiplexing (OFDM), which has a flat optical spectrum and which is thus inherently sensitive to high frequency distortions, e.g., due to limited detector bandwidth. The key to homodyne detection is recovery of the carrier from the received signal all optically (as opposed to frequency offset compensation via digital signal processing. Herein we use optical injection locking (OIL) in conjunction with carrier tone-assisted OFDM to achieve this. In contrast to previous reports, we show that OIL carrier recovery with subsequent homodyne detection can operate without the need for any optical pre-filtering. First, we evaluate the performance as a function of the carrier tone guardband bandwidth. Further, we improve the robustness of this technique using a slow phase lock loop that compensates for drift in the laser’s temperature/current control electronics. Using this improved setup, we compare our all-optical-carrier-recovered homodyne and the ‘traditional’ DSP-assisted intradyne detection for the case of OFDM-16QAM signals. Finally, we compare the computing complexity necessary for both approaches and estimate the intradyne performance limitations due to the carrier-local oscillator frequency offse

Simple geometric interpretation of signal evolution in phase-sensitive fibre optic parametric amplifier

Visualisation of complex nonlinear equation solutions is a useful analysis tool for various scientific and engineering applications. We have re-examined the geometrical interpretation of the classical nonlinear four-wave mixing equations for the specific scheme of a phase sensitive one-pump fiber optical parametric amplification, which has recently attracted revived interest in the optical communications due to potential low noise properties of such amplifiers. Analysis of the phase portraits of the corresponding dynamical systems provide valuable additional insight into field dynamics and properties of the amplifiers. Simple geometric approach has been proposed to describe evolution of the waves, involved in phase-sensitive fiber optical parametric amplification (PS-FOPA) process, using a Hamiltonian structure of the governing equations. We have demonstrated how the proposed approach can be applied to the optimization problems arising in the design of the specific PS-FOPA scheme. The method considered here is rather general and can be used in various applications

Technische Grundlagen der Beschallung von Räumen

Jegliche Form der Beschallung, von kleinen Einbaulautsprechern im Auto bis zu großvolumigen Line Array Systemen in Sportstadien oder bei Open Air Events mit 100.000 Zuhörern, benötigt ein elektroakustisches Wandlersystem, d. h. ein Gerät, das elektrische Energie in Schallwellen verwandelt. Die Eigenschaften des damit aufgebauten Lautsprechers hängen vom physikalischen Prinzip und von der Konstruktion des Wandlers (auch als Treiber bezeichnet) ebenso ab wie von seinem Einbau in ein Gehäuse und der vorgeschalteten Elektronik. Sobald mehr als ein einzelner Lautsprecher betrieben wird, ergeben sich die Eigenschaften der Beschallungsanlage als Ganzes daraus, wie verschiedene Lautsprecher zusammenwirken, um in einem mehr oder weniger ausgedehnten Hörbereich einen gut ausbalancierten Höreindruck zu erreichen. Dies reicht von der zweikanaligen Stereo-Wiedergabe bis zu Systemen mit mehreren Hundert Lautsprechern und entsprechend komplexer Signalverteilung. Dieser Systematik folgt der Aufbau des Kapitels, das zunächst den Aufbau eines einzelnen Lautsprechers behandelt, um in einem zweiten Abschnitt auf Prinzipien beim Zusammenwirken mehrerer Lautsprecher einzugehen, die man je nach Anwendung als Wiedergabeverfahren oder als Beschallungstechnik bezeichnen kann