The origin and relations of the anterior choroidal artery: an anatomical study

There has recently been an increase in surgical interventions to the inferior temporal lobe. The aim of the present study is to examine the anatomical structure and relations of the anterior choroidal artery, which extends to this region. A mixture of latex and ink was injected into the internal carotid and basilar arteries of 15 brains from fresh cadavers. In 18 out of 30 cases (60%) the anterior choroidal artery arose from the posteroinferior aspect of the internal carotid artery, in 8 (22.2%) from the posterolateral aspect and in 4 (2%) from its anterior part. The diameter of the anterior choroidal artery was 0.94 mm on average (0.7-1.2) and the average distance from the posterior communicating artery was 5.3 mm (3.8-8 mm); its distance to the bifurcation of the carotid was found to be 4.0 mm on average (2.2-8 mm). The cisternal segment of the anterior choroidal artery and the optic tract formed a neurovascular bundle. The branches arising from the plexal segment supply the lateral geniculate body, the thalamus and the optic tract. The resulting knowledge of the neurovascular relations of the anterior choroidal artery provides a safe surgical approach to the inferior temporal lobe

Faster Exponential-Time Approximation Algorithms Using Approximate Monotone Local Search

We generalize the monotone local search approach of Fomin, Gaspers,Lokshtanov and Saurabh [J.ACM 2019], by establishing a connection betweenparameterized approximation and exponential-time approximation algorithms formonotone subset minimization problems. In a monotone subset minimizationproblem the input implicitly describes a non-empty set family over a universeof size $n$ which is closed under taking supersets. The task is to find aminimum cardinality set in this family. Broadly speaking, we use approximatemonotone local search to show that a parameterized $\alpha$-approximationalgorithm that runs in $c^k \cdot n^{O(1)}$ time, where $k$ is the solutionsize, can be used to derive an $\alpha$-approximation randomized algorithm thatruns in $d^n \cdot n^{O(1)}$ time, where $d$ is the unique value in $d \in(1,1+\frac{c-1}{\alpha})$ such that$\mathcal{D}(\frac{1}{\alpha}\|\frac{d-1}{c-1})=\frac{\ln c}{\alpha}$ and$\mathcal{D}(a \|b)$ is the Kullback-Leibler divergence. This running timematches that of Fomin et al. for $\alpha=1$, and is strictly better when$\alpha >1$, for any $c > 1$. Furthermore, we also show that this result can bederandomized at the expense of a sub-exponential multiplicative factor in therunning time. We demonstrate the potential of approximate monotone local search by derivingnew and faster exponential approximation algorithms for Vertex Cover,$3$-Hitting Set, Directed Feedback Vertex Set, Directed Subset Feedback VertexSet, Directed Odd Cycle Transversal and Undirected Multicut. For instance, weget a $1.1$-approximation algorithm for Vertex Cover with running time $1.114^n\cdot n^{O(1)}$, improving upon the previously best known $1.1$-approximationrunning in time $1.127^n \cdot n^{O(1)}$ by Bourgeois et al. [DAM 2011].<br

Utjecaj zamrzavanja i metoda ambalažiranja na udjel organskih kiselina kozjeg sira tijekom skladištenja

Effects of freezing and packaging methods on organic acid content of goat cheese during 12 weeks of storage were determined. Goat cheese milk curds were divided into two batches; one of the batches was directly processed in to goat cheese while the other was frozen at -18 °C and stored for six months and processed into cheese after being thawed. Cheese samples were packed in three parts and stored at 4 °C refrigerated control sample and at -18 °C for six months frozen experimental samples. Cheese samples were packed in three different packaging methods: aerobic, vacuum or modified atmosphere. Citric, malic, fumaric, acetic, lactic, pyruvic and propionic acids were analyzed using HPLC method after 1st, 3rd, 6th, 9th and 12th week of storage period. Lactic acid was the main organic acids while pyruvic acid had the lowest content in all cheese samples. Citric and fumaric acid levels of frozen samples increased during storage whereas malic, acetic, pyruvic and propionic acid amounts were decreased compared to the beginning of storage. Packaging methods and freezing process also effected lactic acid levels statistically (p<0.05). Fumaric, acetic and lactic acid concentration of refrigerated samples were increased but citric, malic and propionic acids decreased during storage. Pyruvic acid level did not change significantly. It was determined that organic acid concentrations were effected by freezing process, storage time and packaging methods significantly (p<0.05).U istraživanju je utvrđen utjecaj zamrzavanja i metoda ambalažiranja na udjel organskih kiselina kozjeg sira tijekom 12 tjedana skladištenja. Gruš sira od kozjeg mlijeka bio je podijeljen u dva dijela - kao kontrolni uzorak pohranjen u hladnjaku na 4 °C i kao zamrznuti eksperimentalni uzorak na -18 °C tijekom šest mjeseci. Nakon toga, sirevi su pakirani trima različitim metodama pakiranja: aerobnom, vakuum ili modificiranom atmosferom. Citronska, jabučna, mravlja, octena, mliječna, pirogrožđana i propionska kiselina analizirane su HPLC metodom nakon 1., 3., 6., 9. i 12. tjedna razdoblja čuvanja. Mliječna kiselina bila je najvažnija organska kiselina, dok je pirogrožđana imala najniži udjel u svim uzorcima sira. Tijekom skladištenja došlo je do povećanja udjela citronske i mravlje kiseline smrznutih uzoraka, dok su udjeli jabučne, octene, pirogrožđane i propionske kiseline opadali u odnosu na početak pohrane. Metode pakiranja i proces zamrzavanja također su statistički utjecali na udjel mliječne kiseline (p<0,05). Koncentracije mravlje, octene i mliječne kiseline ohlađenih uzoraka bile su povećane, dok su citronske, jabučne i propionske kiseline opadale tijekom skladištenja. Razina pirogrožđane kiseline nije se značajno promijenila. Utvrđen je statistički značajan utjecaj procesa zamrzavanja, vremena pohrane i metoda pakiranja na koncentracije organskih kiselina (p <0,05)

Diffraction field computation from arbitrarily distributed data points in space

Cataloged from PDF version of article.Computation of the diffraction field from a given set of arbitrarily distributed data points in space is an important signal processing problem arising in digital holographic 3D displays. The field arising from such distributed data points has to be solved simultaneously by considering all mutual couplings to get correct results. In our approach, the discrete form of the plane wave decomposition is used to calculate the diffraction field. Two approaches, based on matrix inversion and on projections on to convex sets (POCS), are studied. Both approaches are able to obtain the desired field when the number of given data points is larger than the number of data points on a transverse cross-section of the space. The POCS-based algorithm outperforms the matrix-inversion-based algorithm when the number of known data points is large. (C) 2006 Elsevier B.V. All rights reserved

Neurovascular relationship between abducens nerve and anterior inferior cerebellar artery

We aimed to study the neurovascular relationships between the anterior inferior cerebellar artery (AICA) and the abducens nerve to help determine the pathogenesis of abducens nerve palsy which can be caused by arterial compression. Twenty-two cadaveric brains (44 hemispheres) were investigated after injected of coloured latex in to the arterial system. The anterior inferior cerebellar artery originated as a single branch in 75%, duplicate in 22.7%, and triplicate in 2.3% of the hemispheres. Abducens nerves were located between the AICAs in all hemispheres when the AICA duplicated or triplicated. Additionally, we noted that the AICA or its main branches pierced the abducens nerve in five hemispheres (11.4%). The anatomy of the AICA and its relationship with the abducens nerve is very important for diagnosis and treatment. (Folia Morphol 2010; 69, 4: 201-203

Performance assessment of a diffraction field computation method based on source model

Efficient computation of scalar optical diffraction field due to an object is an essential issue in holographic 3D television systems. The first step in the computation process is to construct an object. As a solution for this step, we assume that an object can be represented by a set of distributed data points over a space. The second step is to determine which algorithm provides better performance. The source model whose performance is investigated is based on superposition of the diffraction fields emanated from the hypothetical light sources located at the given sample points. Its performance is evaluated according to visual quality of the reconstructed field and its algorithmic complexity. Source model provides acceptable reconstructed patterns when the region in which the samples are given has a narrow depth along the longitudinal direction and a wide extent along the transversal directions. Also, the source model gives good results when the cumulative field at the location of each point due to all other sources tends to be independent of that location. ©2008 IEEE

Bessel functions - Based reconstruction of non-uniformly sampled diffraction fields

A discrete computational model for the diffraction process is essential in forward problems related to holographic TV. The model must be as general as possible, since the shape of the displayed objects does not bear any restrictions. We derive a discrete diffraction model which suits the problem of reconstruction of diffraction fields from a set of non-uniformly distributed samples. The only restriction of the model is the wave nature of the field. The derivation takes advantage of changing the spatial and frequency coordinates to polar form and ends up with a model stated in terms of Bessel functions. The model proves to be a separable orthogonal basis. It shows rapid convergence when evaluated in the framework of the non-uniform sampling problem

Reconstruction of scalar diffraction field from distributed data points over 3D space

Diffraction field computation is an important task in the signal conversion stage of the holographic 3DTV. We consider an abstract setting, where the diffraction field of the desired 3D scene to be displayed is given by discrete samples distributed over 3D space. Based on these samples, a model of the diffraction field should be built to allow the field computation at any desired point. In our previous works, we have proved our concepts for the simplistic 2D case. In this paper, we generalize the earlier proposed techniques, namely the projection onto convex sets and conjugate gradient based techniques and test them for their computational efficiency and memory requirements for a specific 3D case

Signal processing problems and algorithms in display side of 3DTV

Two important signal processing problems in the display side of a holographic 3DTV are the computation of the diffraction field of a 3D object from its abstract representation, and determination of the best display configuration to synthesize some intended light distribution. To solve the former problem, we worked on the computation of ID diffraction patterns from discrete data distributed over 2D space. The problem is solved using matrix pseudo-inversion which dominates the computational complexity. Then, the light field synthesis problem by a deflectable mirror array device (DMAD) is posed as a constrained linear optimization problem. The formulation makes direct application of common optimization algorithms quite easy. The simulations indicate that developed methods are promising. ©2006 IEEE