Multidimensional optimization algorithms numerical results

This paper presents some multidimensional optimization algorithms. By using the "penalty function" method, these algorithms are used to solving an entire class of economic optimization problems. Comparative numerical results of certain new multidimensional optimization algorithms for solving some test problems known on literature are shown.optimization algorithm, multidimensional optimization, penalty function

HEURISTIC AND OPTIMUM SOLUTIONS IN ALLOCATION PROBLEMS

In this paper we present some models and algoritms for solving some typical production planning and scheduling problems. We present the Resource-Constrained Project Scheduling Problem (RCPSP) and algorithms for the determination of maximal couplings with minimal arch length in the graph attached to an allocation problem, and for the determination of the solution of Dirichlet problem and of the potential-voltage problem which appear in a production planning. We develop a model for allocating work among potential VO partners, taking into account fixed and variable work costs and transportation costs.Dirichlet’s problem, conex graph, maximal coupling, RCPS problem, virtual organization, allocation problem

Empirical evidence on risk aversion for individual romanian capital market investors

The evolution of stock prices is influenced by the expectations of investors regarding the earning prospects associated to each listed company. One of the key elements of investment decision is the positive relationship between risk and return. Risky securities are preferred to less risky ones only if there is a higher pay-off in the long run that could compensate the investors. The previous studies proved that expected return direct correlated with risk and, due to the presence of risk aversion, this relationship is assumed to be positive one. Risk premium is determined by a lot of factors including risk aversion. The intensity of risk aversion and the evolution of it during a specific period of time are very important for any market. This study proposed an analysis of risk aversion that is based on a specific survey and it is very useful for comparative analysis with other similar studies developed on the case of other emerging markets (from EU or outside EU).risk aversion, individual investor, Romanian capital market

Similarities between the Acquirer and the Target Company in Successful Takeover Bid Offers

AbstractIn order to narrow the high competition between firms that operates in the same industry, mergers and acquisitions (M&As) transactions are frequently encountered in Romania. In many M&As can be found some similarities between the acquirer and the target company. The study analyze how a successful takeover bid offer is influenced by similarities regarding the age, the geographical position, the industry or ownership between the acquirer and the target company. The results point out that some variables have an important influence on the successful takeover bid, while others are not significant in the acquirer's point of view

Pluteus aurantiorugosus (Trog) Sacc. and Coprinus patouillardii Quél. – new records of macrofungi for Romania

The paper gives a new contribution to the knowledge of macrofungi from Romania. Pluteus aurantiorugosus (Trog) Sacc. is considered a rare macrofungus throughout Europe and this is the first report of this species in Romania. Coprinus patouillardii Quél. is a coprinoid species which is rarely mentioned, probably due to its small size, being usually overlooked. The species was uncovered and identified during a larger research regarding the diversity and distribution of macrofungi in the areas near Bucharest, Romania

The influence of the shapes of a model of an individual house on the pressures of the air currents in the wind

Wind tunnels have been largely used when numerical methods don’t retrieve satisfying re-sults. Pressure values cannot be obtained using numerical methods in different areas of a model because they are not yielded individually. These values are important in determin-ing the forces that act on the different components of a model or structure. By using wind tunnels and by carefully placing transducers (Pitot – Prandtl tubes) in the areas that are of specific interest we can acquire the exact distribution of pressure values which can be subsequently used in determining the forces that take place around the model. In this arti-cle we are presenting the results obtained through experimental tests done in a wind tun-nel owned by the Faculty of Naval Architecture on a scaled down model of an individual house. Using a Pitot – Prandtl tube that was placed in specific areas we observed and measured the pressures that formed at different wind speeds and incidence angles

The Use of Mechanical Suture in the Treatment of Hirschsprung's Disease: Experience of 17 Cases

Rezumat Folosirea suturii mecanice în tratamentul bolii Hirschsprung -o experienåã de 17 cazuri Introducere: Boala Hirschsprung sau megacolonul congenital este o malformaåie caracterizatã prin absenåa celulelor ganglionare la nivelul intestinului distal. Zona de aganglionozã cuprinde cel mai frecvent rectul aei o parte din sigmoid, dar ea se poate întinde pe lungimi variabile. În ultimii ani tratamentul chirurgical al acestei afecåiuni s-a îmbunãtãåit semnificativ, atât prin introducerea procedeului de coborare a colonului pe cale perinealã transanalã, asistat sau nu laparoscopic, cât aei prin dezvoltarea tehnicilor de sutura mecanicã. Scop: Lucrarea îaei propune sã analizeze rezultatele noastre cu procedeul Duhamel modificat, folosind sutura mecanicã pentru realizarea anastomozei colo-rectale latero-laterale. Materiale aei metode: Au fost analizate 17 cazuri de megacolon congenital operate în departamentul nostru între anii 2007 aei 2011 de cãtre aceeaaei echipa de chirurgi pediatri, utilizând tehnica Duhamel modificatã prin folosirea suturii mecanice. Este prima serie operatã în åara noastrã prin acest procedeu. 2 pacienåi au avut forma întinsã de aganglionozã colonicã, 2 au prezentat segment aganglionotic scurt, iar 13 pacienåi au avut forma comunã a bolii. Am urmãrit detaliile tehnice, perioada de spitalizare, precum aei complicaåiile imediate aei cele la distanåã. Rezultate: Perioada medie de spitalizare a fost de 9 zile. Mortalitatea în seria analizatã a fost 0. Complicaåiile postoperatorii au constat în: rectoragie minorã (5 cazuri), ocluzie prin bride (1 caz) aei sindrom subocluziv determinat de prezenåa unui sept restant cu dezvoltarea consecutivã de fecalom în ampula rectalã (4 cazuri). Toate cazurile operate din aceastã serie au avut în final o continenåã de materii fecale foarte bunã. Concluzii: În opinia noastrã folosirea dispozitivelor de suturã mecanicã în cadrul unui procedeu Duhamel într-o singurã etapa este deosebit de beneficã, atât în ceea ce priveaete rata complicaåiilor, cât aei durata de spitalizare. Aceastã tehnicã este sigurã, simplã aei eficientã. Cuvinte cheie: boala Hirschsprung, procedeul Duhamel, dispozitive de sutura mecanicã Abstract Introduction: Hirschsprung's disease, or congenital megacolon, is a malformation characterised by the absence of ganglion cells in the distal bowel. Most often, the aganglionic segment includes the rectosigmoid, but it may extend proximally to variable length. In late years, significant improvements regarding the surgical treatment of Hirschsprung's disease were made, by the introduction of both one-stage transanal endorectal pull-through -laparoscopically assisted or not -and mechanical suture devices Aim: The purpose of this paper is to analyse our results with modified Duhamel procedure by using mechanical sutures for construction of a side-to-side colo-rectal anastomosis Materials and Method: We analysed 17 congenital megacolon cases operated in our department between 2007 -2011 by the same pediatric surgical team, using the modified Duhamel technique performed with mechanical suture. It is the first series operated in our country using this procedure. 2 patients had a long colonic aganglionosis, 2 patients had a short aganglionotic segment and 13 patients had the common form Results: The mean hospitalization period was of 9 days. Mortality in our series was 0. Postoperative complications consisted in minor bleeding (5 cases), adhesions and mechanical occlusion (1 case), and subocclusive symptoms due to remnant septum with subsequent fecaloma formation in the rectal ampula (4 cases). All of our operated cases had consequently a very good fecal continence. Conclusions: We think that usage of mechanical suture devices in a single stage Duhamel procedure is extremely beneficial regarding both complication rate and hospitalisation time. This technique is safe, simple and efficient

Clonal Progression during the T Cell-Dependent B Cell Antibody Response Depends on the Immunoglobulin DH Gene Segment Repertoire

The diversity of the third complementarity determining region of the IgH chain is constrained by natural selection of immunoglobulin diversity (D(H)) sequence. To test the functional significance of this constraint in the context of thymus-dependent (TD) immune responses, we immunized BALB/c mice with WT or altered D(H) sequence with 2-phenyloxazolone-coupled chicken serum albumin (phOx-CSA). We chose this antigen because studies of the humoral immune response to the hapten phOx were instrumental in the development of the current theoretical framework on which our understanding of the forces driving TD responses is based. To allow direct comparison, we used the classic approach of generating monoclonal Ab (mAb) from various stages of the immune response to phOx to assess the effect of changing the sequence of the D(H) on clonal expansion, class switching, and affinity maturation, which are hallmarks of TD responses. Compared to WT, TD-induced humoral IgM as well as IgG antibody production in the D-altered ΔD-DμFS and ΔD-iD strains were significantly reduced. An increased prevalence of IgM-producing hybridomas from late primary, secondary, and tertiary memory responses suggested either impaired class switch recombination (CSR) or impaired clonal expansion of class switched B cells with phOx reactivity. Neither of the D-altered strains demonstrated the restriction in the V(H)/V(L) repertoire, the elimination of V(H)1 family-encoded antibodies, the focusing of the distribution of CDR-H3 lengths, or the selection for the normally dominant Ox1 clonotype, which all are hallmarks of the anti-phOx response in WT mice. These changes in clonal selection and expansion, as well as CSR indicate that the genetic constitution of the D(H) locus, which has been selected by evolution, can strongly influence the functional outcome of a TD humoral response

Variation of the Oswestry Disability Index in Patients with Lumbar Vertebral Discopathy, Surgically Treated

The prospective study was performed to highlight the evolution of the Oswestry Disability Index (ODI), before and after surgical treatment of lumbar disc herniation. A group of 100 patients was used, hospitalized and treated surgically in the Neurosurgery Department of the Constanta County Hospital, between 01.08.2020-31.12.2021. The study took into account general patient data (age, sex, provenience), comorbidities (obesity, diabetes, hypertension, chronic treatment with antiplatelet agents before surgery) and the presence of aggravating factors of lumbar vertebral disc disease with indication surgery (presence of polydiscopathy, motor deficit, preoperative and postoperative disc recurrence). There was a significant improvement in the severity of the degree of disability of surgically treated patients, both at one month and at 3 months, postoperatively. The improvement of the degree of disability was different, given the presence of aggravating factors, preoperatively and also the occupational factor, which delayed the postoperative clinical evolution, both, by rapid reintegration into daily life with physical effort and by the production of recurrences of discal pathology