DECOMPOSITION METHOD IN COMPARISON WITH NUMERICAL SOLUTIONS OF BURGERS EQUATION

This paper presents a solution of the one-dimension Burgers equation using Decomposition Method and compares this solution to the analytic solution [Cole] and solutions obtained with other numerical methods. Even though decomposition method is a non-numerical method, it can be adapted for solving nonlinear differential equations. The advantage of this methodology is that it leads to an analytical continuous approximated solution that is very rapidly convergent [2,7,8]. This method does not take any help of linearization or any other simplifications for handling the non-linear terms. Since the decomposition parameter, in general, is not a perturbation parameter, it follows that the non-linearities in the operator equation can be handled easily, and accurate solution may be obtained for any physical problem

Directed Graphs representing isomorphism classes of C-Hypergroupoids

We investigate the relation of directed graphs and hyperstructures by virtue of the graph hyperoperation. A new class of graphs arises in this way representing isomorphism classes of C-hypergroupoids and we present the 17 such graphs that correspond to the 73 C-hypergroupoids associated with binary relations on three element sets. As it is shown they constitute an upper semilattice with respect tograph inclusion

Interval valued intuitionistic (S,T)(S,T)-fuzzy HvH_v-submodules

On the basis of the concept of the interval valued intuitionistic fuzzy sets introduced by K.Atanassov, the notion of interval valued intuitionistic fuzzy $H_v$-submodules of an $H_v$-module with respect to $t$-norm $T$ and $s$-norm $S$ is given and the characteristic properties are described. The homomorphic image and the inverse image are investigated.In particular, the connections between interval valued intuitionistic $(S,T)$-fuzzy $H_v$-submodules and interval valued intuitionistic $(S,T)$-fuzzy submodules are discussed

Successful combined surgical approach in a rare case of retrotracheal goitre in a patient with anatomical impediments

Diving goitres can descend the cervical region expanding directly into the thoracic cavity. In most cases, diving goitres extend into the anterosuperior compartment, but they may also extend behind the trachea. We herein present a case of a male patient with retrotracheal goitre and history of left thyroid lobectomy and median sternotomy for thoracic aortic aneurysm repair with graft placement. After detailed preoperative evaluation, the patient underwent surgical resection of the mass through a combined approach; the existing cervical incision and a right posterolateral mini-thoracotomy. The postoperative course of the patient was uncomplicated. One year after surgery, the patient is asymptomatic and disease-free. (Folia Morphol 2018; 77, 1: 166–169

Recognizability in Stochastic Monoids

Stochastic monoids and stochastic congruences are introduced and the syntactic stochastic monoid M L associated to a subset L of a stochastic monoid M is constructed. It is shown that M L is minimal among all stochastic epimorphisms h : M → M ′ whose kernel saturates L. The subset L is said to be stochastically recognizable whenever M L is finite. The so obtained class is closed under boolean operations and inverse morphisms

Fuzzy graphs: Algebraic structure and syntactic recognition

© Springer Science+Business Media Dordrecht 2013. Directed fuzzy hypergraphs are introduced as a generalization of both crisp directed hypergraphs and directed fuzzy graphs. It is proved that the set of all directed fuzzy hypergraphs can be structured into a magmoid with operations graph composition and disjoint union. In this framework a notion of syntactic recognition inside magmoids is defined. The corresponding class is proved to be closed under boolean operations and inverse mor-phisms of magmoids. Moreover, the language of all strongly connected fuzzy graphs and the language that consists of all fuzzy graphs that have at least one directed path from the begin node to the end node through edges with membership grade 1 are recognizable. Additionally, a useful characterization of recognizability through left derivatives is also achieved

Large thoracic tumour without superior vena cava syndrome

A 62-year-old male with long-standing smoking history presented with haemoptysis. Plain chest X-ray showed abnormal findings proximate to the right pulmonary hilum. Bronchoscopy revealed a fragile exophytic tumour of the right wall of the lower third of the trachea, infiltrating the right main bronchus (75% stenosis) and the right upper lobar bronchus (near total occlusion). Contrast-enhanced chest computed tomography demonstrated a 7.2 × 4.9 cm tumour contiguous to the above-mentioned structures, mediastinal lymph node pathology, and a vessel coursing inferiorly to the left of the aortic arch and anterior to the left hilum. Despite the tumour constricting the right superior vena cava (SVC), no signs of SVC syndrome were present. In this case, the patient does not present with SVC syndrome, as expected due to the constriction of the (right) SVC caused by the tumour, since head and neck veins drain through the persistent left superior vena cava (PLSVC). PLSVC is the most common thoracic venous anomaly with an incidence of 0.3% to 0.5% of the general population and it is a congenital anomaly caused by the failure of the left anterior cardinal vein to regress and to consequently form the ligament of Marshall during foetal development. It is associated with absence of the left brachiocephalic vein and in 10% to 20% of cases the right SVC is absent. Two potential draining points of the PLSVC have been previously reported. In the majority of cases PLSVC drains directly into the coronary sinus, but less frequently it drains into the left atrium or the left superior pulmonary vein (LSPV). In cases where the PLSVC drains into the coronary sinus, congenital heart defects are rare. The patient usually remains asymptomatic and PLSVC is an incidental finding during radiographic imaging or medical procedures. When the PLSVC drains into the left atrium or the LSPV, a right-to-left shunt is formed; a condition usually asymptomatic. In some reported cases this PLSVC variant presents with persistent, unexplained hypoxia or cyanosis and embolisation causing recurrent transient ischaemic attacks and/or cerebral abscesses. This PLSVC variant is more often associated with absence of the right SVC and congenital heart abnormalities.

Ο ρόλος της πρασουγρέλης στην αντιμετώπιση καρδιαγγειακών συμβαμάτων - Νεότερα δεδομένα

Η διπλή αντιαιμοπεταλιακή αγωγή παραμένει ο ακρογωνιαίος λίθος της φαρμακευτικής αντιμετώπισης των ασθενών με οξύ στεφανιαίο σύνδρομο. Ο συνδυασμός της ασπιρίνης και του P2Y12 αναστολέα μειώνει τα ποσοστά θρόμβωσης του stent και των μείζονων καρδιαγγειακών συμβαμάτων στους ασθενείς με οξύ στεφανιαίο σύνδρομο που αντιμετωπίζονται με αγγειοπλαστική. Παρ᾽ όλα αυτά οι ασθενείς παραμένουν σε αυξημένο κίνδυνο υποτροπής καρδιαγγειακών συμβαμάτων παρά την υπάρχουσα φαρμακευτική θεραπεία. Για αυτούς τους λόγους και λόγω της ποικίλης και καθυστερημένης αντιαιμοπεταλιακής δράσης της κλοπιδογρέλης, έχουν αναπτυχθεί νέοι αναστολείς P2Y12. Η πρασουγρέλη είναι ένα προφάρμακο που χρειάζεται βιολογική μετατροπή στους ενεργούς μεταβολίτες της. Είναι εκλεκτικός αναστολέας των υποδοχέων ADP με θεραπευτική ένδειξη τα οξέα στεφανιαία σύνδρομα. Η πρασουγρέλη έχει ταχύτερη έναρξη δράσης και παρέχει μεγαλύτερη αναστολή των αιμοπεταλίων σε σχέση με την κλοπιδογρέλη. Η μεγάλη, πολυκεντρική, τυχαιοποιημένη, διπλή τυφλή μελέτη TRITON TIMI 38 απέδειξε ότι η πρασουγρέλη είναι πιο αποτελεσματική από την κλοπιδογρέλη στη μείωση των πρωτογενών καταληκτικών σημείων (μη θανατηφόρο έμφραγμα του μυοκαρδίου, αγγειακό εγκεφαλικό επεισόδιο και καρδιαγγειακός θάνατος) στους ασθενείς με οξέα στεφανιαία επεισόδια. Η πρασουγρέλη μείωσε ακόμα και τη θνητότητα (ανεξαρτήτως αιτιολογίας) στη μελέτη αυτή. Το κλινικό όφελος της πρασουγρέλης φάνηκε στους ασθενείς που αντιμετωπίζονταν επεμβατικά. Ο κίνδυνος όμως μείζονων αιμορραγιών με την πρασουγρέλη (σχετιζόμενων και μη με CABG) είναι πολύ μεγαλύτερος σε σχέση με την κλοπιδογρέλη. Η μελέτη κατέληξε στο συμπέρασμα ότι παρά το μεγαλύτερο ποσοστό αιμορραγιών, το κλινικό όφελος από τη χρησιμοποίηση της πρασουγρέλης είναι μεγαλύτερο σε σχέση με την κλοπιδογρέλη. Οι μόνες κατηγορίες που δεν έχουν κλινικό όφελος είναι οι ασθενείς με ιστορικό αγγειακού εγκεφαλικού επεισοδίου, παροδικού εγκεφαλικού επεισοδίου, ασθενείς >75 ετών και ασθενείς με βάρος <60 kg. H μελέτη TRILOGY ACS συνέκρινε την πρασουγρέλη και την κλοπιδογρέλη σε ασθενείς που αντιμετωπίστηκαν συντηρητικά χωρίς να αναδείξει κάποια σαφή υπεροχή του ενός ή του άλλου φαρμάκου. Οι οδηγίες της Ευρωπαϊκής Καρδιολογικής Εταιρείας παρουσιἀζουν αυτή τη στιγμή την πρασουγρέλη και την τικαγρελόρη ως τα αντιαιμοπεταλιακά φάρμακα πρώτης γραμμής στην αντιμετώπιση των οξέων στεφανιαίων επεισοδίων (NSTE-ACS και STEMI). Οι οδηγίες αυτές βασίζονται σε μεγάλες τυχαιοποιημένες μελέτες που απέδειξαν το κλινικό όφελος των φαρμάκων αυτών σε σχέση με την κλοπιδογρέλη. Το 2009 η Ευρωπαϊκή Επιτροπή και ο FDA ενέκριναν τη χρήση της πρασουγρέλης σε συνδυασμό με την ασπιρίνη για τη μείωση καρδιαγγειακών συμβαμάτων σε ασθενείς με οξύ στεφανιαίο επεισόδιο που πρόκειται να αντιμετωπιστούν επεμβατικά (συμπεριλαμβανομένων και αυτών της θρόμβωσης του stent). H πρασουγρέλη αμφισβητείται πλέον από την τικαγρελόρη, ένα αναστολέα του υποδοχέα P2Y12 με διαφορετικές φαρμακοκινητικές και φαρμακοδυναμικές ιδιότητες. Η ανωτερότητα του ενός σε σχέση με το άλλο φάρμακο δεν έχει πλήρως αποσαφηνιστεί από τις έως τώρα δημοσιευμένες μελέτες. Περαιτέρω μακροπρόθεσμα δεδομένα για την ασφάλεια και την αποτελεσματικότητα της πρασουγρέλης είναι αναγκαία για να ξεκαθαρίσουν τον ακριβή ρόλο της πρασουγρέλης σε σχέση με τα άλλα αντιαιμοπεταλιακά φάρμακα. Υπάρχουν ήδη τρέχουσες μελέτες προς αυτή την κατεύθυνση. Από την υπάρχουσα βιβλιογραφία συνάγεται το συμπέρασμα ότι η πρασουγρέλη αποτελεί ένα χρήσιμο εργαλείο για την πρόληψη καρδιαγγειακών συμβαμάτων, τα οποία πρόκειται να αντιμετωπιστούν επεμβατικά.Dual antiplatelet therapy remains the cornerstone of the medical management of patients with acute coronary syndrome (ACS). In ACS patients receiving a coronary stent, the combination of aspirin and a P2Y12 inhibitor reduces rates of stent thrombosis and major adverse cardiovascular events. However, patients with acute coronary syndrome still remain at risk of recurrent cardiovascular events despite the advance of medical therapy. Given the well‐known limitations of clopidogrel with variable antiplatelet effects and delayed onset of action, newer P2Y12 inhibitors have been developed. Prasugrel is a prodrug that requires biologic conversion to active metabolites. Prasugrel is a selective adenosine diphosphate (ADP) receptor antagonist indicated for use in patients with acute coronary syndromes (ACS). Prasugrel has a faster onset of action and provides greater inhibition of platelet aggregation than clopidogrel. in the large, randomized, double-blind, multicentre, TRITON TIMI 38 trial in adult patients with ACS, treatment with prasugrel was more effective than clopidogrel in reducing the incidence of the primary composite endpoint of non-fatal myocardial infarction, stroke, or cardiovascular (CV) death. Prasugrel also reduced all-cause mortality relative to clopidogrel. Benefit with prasugrel was seen in invasively managed patients. Prasugrel was generally well tolerated and was associated with an increased risk of major bleeding relative to clopidogrel. The risk of major bleeding with prasugrel (including bleeds related to CABG and non-CABG) was higher than with clopidogrel. After taking into account the higher bleeding rates, the net clinical benefit still favored prasugrel use compared with clopidogrel. However, patients with prior stroke or TIA, patients older than 75 years, and patients weighing <60 kg did not demonstrate a net clinical benefit with prasugrel use. The TRILOGY ACS trial found no benefit with prasugrel compared to clopidogrel in patients with medically treated ACS. Prasugrel and ticagrelor are now the recommended first-line agents in patients presenting with non-ST-segment elevation ACS and ST-segment elevation ACS, due to large-scale randomized trials that demonstrated net clinical benefit of these agents over clopidogrel, as stated in the European guidelines. In 2009, the European Commission and US Food and Drug Administration (FDA) approved the use of prasugrel in combination with aspirin for the reduction of thrombotic cardiovascular events (including stent thrombosis) in patients with acute coronary syndrome who are to be managed with PCI. Prasugrel is currently challenged by ticagrelor, a P2Y12 receptor antagonist with different pharmacokinetic/pharmacodynamic properties. The superiority of one drug to the other cannot be reliably estimated from the current trials. Further long-term and comparative efficacy and tolerability data are required to definitively position prasugrel with respect to other antiplatelet agents, including ticagrelor. Ongoing randomized and observational studies may help to provide valuable information on the safety and efficacy of these two drugs and their respective places with ACS patients. Current evidence indicates that prasugrel is a useful option for the prevention of thrombotic CV events in ACS patients managed invasively