Hindrance of ^{16}O+^{208}Pb fusion at extreme sub-barrier energies

We analyze the fusion data for $^{16}$O+$^{208}$Pb using coupled-channels calculations. We include couplings to the low-lying surface excitations of the projectile and target and study the effect of the ($^{16}$O,$^{17}$O) one-neutron pickup. The hindrance of the fusion data that is observed at energies far below the Coulomb barrier cannot be explained by a conventional ion-ion potential and defining the fusion in terms of ingoing-wave boundary conditions (IWBC). We show that the hindrance can be explained fairly well by applying the M3Y double-folding potential which has been corrected with a calibrated, repulsive term that simulates the effect of nuclear incompressibility. We show that the coupling to one-neutron transfer channels plays a crucial role in improving the fit to the data. The best fit is achieved by increasing the transfer strength by 25% relative to the strength that is required to reproduce the one-neutron transfer data. The larger strength is not unrealistic because the calculated inelastic plus transfer cross section is in good agreement with the measured quasielastic cross section. We finally discuss the problem of reproducing the fusion data at energies far above the Coulomb barrier. Here we do not account for the data when we apply the IWBC but the discrepancy is essentially eliminated by applying the M3Y+repulsion potential and a weak, short-ranged imaginary potential.Comment: text and 8 fifure

Successful Biological Invasion despite a Severe Genetic Load

Understanding the factors that influence the success of ecologically and economically damaging biological invasions is of prime importance. Recent studies have shown that invasive populations typically exhibit minimal, if any, reductions in genetic diversity, suggesting that large founding populations and/or multiple introductions are required for the success of biological invasions, consistent with predictions of the propagule pressure hypothesis. Through population genetic analysis of neutral microsatellite markers and a gene experiencing balancing selection, we demonstrate that the solitary bee Lasioglossum leucozonium experienced a single and severe bottleneck during its introduction from Europe. Paradoxically, the success of L. leucozonium in its introduced range occurred despite the severe genetic load caused by single-locus complementary sex-determination that still turns 30% of female-destined eggs into sterile diploid males, thereby substantially limiting the growth potential of the introduced population. Using stochastic modeling, we show that L. leucozonium invaded North America through the introduction of a very small number of propagules, most likely a singly-mated female. Our results suggest that chance events and ecological traits of invaders are more important than propagule pressure in determining invasion success, and that the vigilance required to prevent invasions may be considerably greater than has been previously considered

Effective recruitment method for the marketing department of a metallurgical enterprise

This paper presents some solutions to recruit staff for the Marketing Department of a metallurgical enterprise. Our goal is to present the psychological characteristics of a certain category of employees on a sample of 107 employees and to evaluate the relationship between the motivation to work and those characteristics. In order to realize such evaluation we used the linear mixed effects model in the statistical software program R. The results showed that a significant effect on work motivation have factors like work climate and the employee agreeability

Assessment of POSSUM score in surgical department

Catedra Chirurgie Generală şi Semiologie, USMF „N.Testemițanu”, Chișinău, Moldova, Al XI-lea Congres al Asociației Chirurgilor „Nicolae Anestiadi” din Republica Moldova și cea de-a XXXIII-a Reuniune a Chirurgilor din Moldova „Iacomi-Răzeșu” 27-30 septembrie 2011Introducere: Aprecierea obiectivă a riscului operator a devenit o condiție esențială pentru practica contemporană a departamentelor chirurgicale. Astfel, scorul POSSUM (Physiological and Operative Severity Score for enUmerating Morbidity and mortality) la momentul actual constituie unul din sistemele precise și accesibile în aprecierea mortalității și morbidității postoperatorii, fiind unul din puținile ce evaluează atît factorii fiziologici individuali cît și cei legați nemijlocit de actul chirurgical. Metode: Au fost analizate retrospectiv 99 de fișe ale pacienților ce s-au aflat la tratament în perioada postoperatorie în departamentul ATI și au inclus informația necesară colectării parametrilor scorului fiziologic (12 paramentrii); precum și a celui operator (6 paramentri). Lipsa aprecierii statutului neurologic comform scalei Glasgow a impus omiterea pacienților cu un scor mai mic de 15p conform acestui indice. Mortalitatea probabilă a fost calculată comform variantei modificate a scalei, P- POSSUM. Analiza statistică a datelor s-a efectuat prin intermediului programului SPSS v.16.0. Rezultate: În lotul de studiu mortalitatea prognozată medie a fost de 12.5%, exprimat în cifre absolute a constituit 12 decese, iar numărul real fiind de 22 decese. Limita de probabilitate a mortalității de 10% pare a fi una critică, 20 din decese clasîndu-se după această valoare. Morbiditatea medie prognozată a constituit 35,4%, cea reală fiind de 31,3%, raportul între numărul de cazuri reale și cele probabile fiind de 0.89. Concluzii: Scorul POSSUM asigură un pronostic relativ veridic al mortalității și morbidității postoperatorii. Prognozarea mai obiectivă a rezultatelor tratamentului chirurgical este strâns legată de determinarea precisă a paramentrilor incluși.Introduction: Objective assessment of operative risk has become an essential condition for the practice of modern surgical departments. Thus, the POSSUM score (Physiological and Operative Severity Score for enUmerating Morbidity and mortality), at this moment, is one of the accurate and accessible systems used for assessment of postoperative mortality and morbidity, one of the few that assesses both individual physiological factors as well as those directly related to the surgery. Methods: We analyzed retrospectively 99 files of patients who have been treated in the postoperative period in the ICU and which included the information necessary for calculation of physiological score (12 parameters), as well as the operative score (6 parameters). Lack of possibility to assess the neurological status using Glasgow scale imposed the exclusion of patients with a score less than 15p. The mortality was calculated with the modified version of the score, P-POSSUM. Statistical data analysis was performed by using SPSS v.16.0. Results: The average forecast mortality was 12.5%, expressed in absolute values it accounted for 12 deaths, while the real number of deaths was 22. The limit of 10% for the probable mortality seems to be a critical one, 20 deaths were observed after this value. Average forecast morbidity was 35.4%, while the real one was 31.3%, the ratio between the number of real and probable cases was 0.89. Conclusions: The POSSUM score provides a relatively truthful prediction of the postoperative mortality and morbidity. Objective forecasting of surgical treatment results is closely connected with precise determination of included parameters

Acceptance conditions in automated negotiation

In every negotiation with a deadline, one of the negotiating parties has to accept an offer to avoid a break off. A break off is usually an undesirable outcome for both parties, therefore it is important that a negotiator employs a proficient mechanism to decide under which conditions to accept. When designing such conditions one is faced with the acceptance dilemma: accepting the current offer may be suboptimal, as better offers may still be presented. On the other hand, accepting too late may prevent an agreement from being reached, resulting in a break off with no gain for either party. Motivated by the challenges of bilateral negotiations between automated agents and by the results and insights of the automated negotiating agents competition (ANAC), we classify and compare state-of-the-art generic acceptance conditions. We focus on decoupled acceptance conditions, i.e. conditions that do not depend on the bidding strategy that is used. We performed extensive experiments to compare the performance of acceptance conditions in combination with a broad range of bidding strategies and negotiation domains. Furthermore we propose new acceptance conditions and we demonstrate that they outperform the other conditions that we study. In particular, it is shown that they outperform the standard acceptance condition of comparing the current offer with the offer the agent is ready to send out. We also provide insight in to why some conditions work better than others and investigate correlations between the properties of the negotiation environment and the efficacy of acceptance condition

Strategies of the treatment of cardiac prosthetic valve thrombosis

Departamentul Cardiochirurgie, Spitalul Clinic Republican, Chişinău, Republica Moldova, Al XII-lea Congres al Asociației Chirurgilor „Nicolae Anestiadi” din Republica Moldova cu participare internațională 23-25 septembrie 2015Introducere: Fenomenul de tromboză şi „pannus” tromboză rămîne printre complicaţiile ce necesită intervenţie promptă în cardiochirurgie. Material şi metode: Din 1670 de pacienţi operaţi în departamentul nostru – 1260 (74,2%) prezentau patologii valvulare. S-au protezat 1164 valve cardiace: din ele 145 – cu proteze biologice; 1019 – cu proteze mecanice. Tromboza protezelor s-a depistat la 28 pacienţi (60% din cazurile disfuncţiilor de proteză şi 2,2% din numărul total al pacienţilor), cu vîrstă cuprinsă între 35 şi 63 de ani. Tratament chirurgical s-a efectuat la 9 pacienţi, tromboliză – la 19 pacienţi. Rezultate: În ultimii 6-7 ani, tratamentul medicamentos de tromboliză în trombozele protezelor valvulare, se realizează reuşit cu alteplaza şi reteplaza. Tromboliza a fost efectuată la 19 pacienţi. Efecte: în 17 cazuri – recuperarea completă a funcţiilor protezelor cu normalizarea gradientului transprotetic şi a presiunii sistolice în ventricolul drept. Au survenit complicaţii: un caz – atac ischemic tranzitor cerebral şi 2 cazuri letale. Concluzii: Pacienţii cu tomboză a protezelor valvulare în stare critică (edem acut pulmonar, hipotensiune, insuficienţă cardiacă IV NYHA) se supun, după confirmare ecografică, terapiei trombolitice intravenoase. Tratamentul de tromboliză are o eficacitate înalta în tromboza protezelor valvulare, rata complicaţiilor cu embolii este joasă, motiv din care tratamentul respectiv poate fi implementat ca unul de primă linie în tromboza protezelor valvulare, în absenţa contraindicaţiilor. În cazul răspunsului parţial la tratamentul de tromboliză, pacientul poate fi operat în condiţii hemodinamice satisfăcătoare şi cu un risc scăzut.Introduction: The phenomenon of thrombosis and “pannus” thrombosis prevails among the complications that require prompt intervention in cardiac surgery. Material and methods: In our department 1670 patients were operated on: 1260 had valve pathology (74.2%). Totally 1164 heart valves were replaced: 145 – biological prostheses and 1019 – mechanical ones. Prosthesis thrombosis took place in 28 patients (60% of prosthetic dysfunction and 2.2% of the total number of operated patients) aged from 35 to 63 years old. Nine patients underwent surgical treatment, 19 patients – were treated by thrombolysis. Results: During last 6-7 years the thrombolysis treatment with alteplase and reteplase has been successfully implemented in the therapy of thrombosis of prosthetic valve. Thrombolysis was performed in 19 patients. The results are the following: in 17 cases – complete recovery of the prosthesis function with normalization of trans-prosthetic gradient and systolic pressure in right ventricle was observed. One case has been complicated with cerebral transitory ischemic attack and 2 cases of mortality were registered. Conclusions: The patients with prosthesis thrombosis who are in critical condition (acute pulmonary edema, hypotension, heart failure NYHA IV) should immediately receive ultrasound confirmation of the need of intravenous thrombolitic therapy. The thrombolysis efficacy in prosthesis thrombosis is high; the rate of embolic complications is low, which can be used as the first line treatment for all patients with prosthetic thrombosis in the absence of contraindications. In the case of partial response to the thrombolysis patient can be operated in satisfactory hemodynamic conditions and with decreased surgical risk

Network analyses in systems biology: new strategies for dealing with biological complexity

The increasing application of network models to interpret biological systems raises a number of important methodological and epistemological questions. What novel insights can network analysis provide in biology? Are network approaches an extension of or in conflict with mechanistic research strategies? When and how can network and mechanistic approaches interact in productive ways? In this paper we address these questions by focusing on how biological networks are represented and analyzed in a diverse class of case studies. Our examples span from the investigation of organizational properties of biological networks using tools from graph theory to the application of dynamical systems theory to understand the behavior of complex biological systems. We show how network approaches support and extend traditional mechanistic strategies but also offer novel strategies for dealing with biological complexity