Case study: An intelligent decision-support system

© 2005 IEEE.The explosive growth in decision-support systems over the past 30 years has yielded numerous "intelligent" systems that have often produced less-than-stellar results. In addition to generating data that users can't immediately apply to their tasks, such systems are often static, rendering them unable to respond to the dynamic nature of both business and the larger world. In this case study, the authors describe a thorny logistical problem: recommending the best distribution for used cars among various automobile auctions. They solved this problem by combining prediction, optimization, and adaptation techniques into one integrated system that has generated impressive profits for a large auto manufacturer.This article is part of a special issue on transportation and logistics.Zbigniew Michalewicz, Martin Schmidt, Matthew Michalewicz, and Constantin Chiria

Case Report: Positive outcome of medical leeches (hirudotherapy) for venous congestion

No Abstrac

Polymerization in Magnetic Field. XIX. Thermal Behavior of the Copolymers of Methyl Methacrylate with Glycidyl Methacrylate Synthesized in the Magnetic Field Presence

n/

Problems in diagnosis and surgical treatment of the retroperitoneal non-pancreatogenic phlegmons

Catedra de Chirurgie, FEC MF, Universitatea de Stat de Medicină și Farmacie ”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 2011Supurațiile ale spațiului retroperitoneal sunt o problemă medico-chirurgicală neobișnuită cu un tablou clinic vag, care prezintă o provocare în aprecierea diagnosticului. Debutul insidios și evoluție ocultă ale acestei patologii sunt urmate de un diagnostic întârziat și drenaj neadecvat, astfel pentru flegmon retroperitoneal sunt caracteristice morbiditatea și mortalitatea considerabile. Anterior au fost publicate studii privind detaliile anatomice ale spațiilor extraperitoneale, dar mai puțina atenție a fost acordată metodelor de diagnostic și tehnicilor chirurgicale de drenaj. Prezentăm o trecere în revistă a 15 de cazuri de inflamații suruprative retroperitoneale nonpancreatogene care s-au manifestat ca entitate clinică principală. În aspect etiologic pacienții s-au repartizat în 5 grupe: psoitele purulente – 4, abcesele retroperitoneale apendiculare - 4, perinefritele purulente - 3, colecții retroperitoneale în urma osteolizei - 3 (ostemielita hematogenă, postraumatică, tuberculoza osoasă), hematom postraumatic retroperitoneal infectat – 1 caz. Trei pacienți (16,7 %) au decedat în perioada postoperatorie precoce. Complicații au survenit la 40 % pacienți. Letalitatea și rata înaltă de complicații au fost asociate cu perioada îndelungată de la debut până la diagnostic pozitiv (> 5 zile) și cu hemocultura pozitivă. Există o corelație între tipuri de complicații și sursa de infecție retroperitoneală. Computer tomografia este metoda cea mai informativă în diagnosticul supurațiilor abdominale extraperitoneale. În cazuri selecte drenajul ecoghidat poate fi folosit ca un gest chirurgical inițial. Descriem tehnica operatorie în dependență de topografia procesului purulent retroperitoneal. Este propus un plan de diagnostic și tratament pentru fiecare grup etiologic.Retroperitoneal space inflammation is an unusual surgical problem with vague clinical presentation, which presents a diagnostic challenge. An insidious onset and occult evolution of illness marked by diagnostic delay, inadequate drainage, and considerable morbidity and mortality is common. Papers regarding anatomic detailing of the extraperitoneal spaces have been published, but less attention has been focused on diagnostic and drainage techniques.We report an analysis of 15 cases of retroperitoneal suppurations which acted as main clinical manifestation. According to etiology of inflammation patients were distributed into 5 groups: psoas abscesses – 4 cases, retroperitoneal appendical abscesses – 4 cases, purulent perinephritis -3, retroperitoneal collections caused by osteolysis – 3 patients (hematogenic, posttraumatic or tuberculous) and one case of infected posttraumatic hematoma.Three patients (16,7 %) died in the early postoperative period. Rate of complications was 40 %. High lethality and postoperative morbidity were associated with positive blood cultures and delayed diagnosis (> 5 days). There is a correlation between the type of complications and etiology of the retroperitoneal phlegmon. Computed tomography is the most informative diagnostic method for the extraperitoneal purulent collections. Echoguided drainage in selected cases appears to be a useful initial approach. The operative technique dependent on the retroperitoneal purulent collection topography is described. A diagnostic and treatment plan is proposed for each etiologic group

Low temperature (down to 450° C) annealed TiAl contacts on N-type gallium nitride characterized by differential scanning calorimetry

International audienceThis work reports on Differential Scanning Calorimetry (DSC) measurements performed on Ti-Al metallic layers stacks deposited on n+-GaN. The aim is to get better understanding of the mechanisms leading to ohmic contact formation during the annealing stage. Two exothermic peaks were found, one below 500°C and the other one around 660°C. They can be respectively attributed to Al3Ti and Al2Ti compounds formation. The locations of these peaks provide clear evidence of solid-solid reac-tions. Lowest contact resistance is well correlated with the presence of Al3Ti compound, corresponding to Al(200nm)/Ti(50nm) stoichiometric ratio. Subsequently, Al(200 nm)Ti(50 nm) stacks on n+-GaN were annealed from 400°C to 650°C. Specific Contact Resistivity (SCR) values stay in the mid 10-5 Ω.cm² range for annealing temperatures between 450°C and 650°C. Such low-temperature annealed contacts on n+-GaN may open new device processing routes, simpler and cheaper, in which Ohmic and Schottky contacts are annealed together

Monolithes de silice et de carbone à porosité hiérarchisée obtenus par frittage SPS

La silice SBA-15 et le carbone CMK-3 possèdent une grande surface spécifique et un volume important de mésopores ordonnés dans une symétrie hexagonale (groupe d’espace p6 mm). Il est nécessaire de préserver leurs caractéristiques lors de la mise en forme de ces matériaux, pour un grand nombre d’applications. Le frittage SPS (Spark Plasma Sintering) des poudres a été effectué sans charge ou avec une charge uniaxiale de 25 MPa et à des températures de 600 à 800 ◦C pour la silice et 1100 à 1300 ◦C pour le carbone, pendant 5 minutes. Les isothermes d’adsorption/désorption d’azote montrent que les monolithes obtenus conservent une surface spécifique élevée (300 à 500 m2/g) et un volume mésoporeux de l’ordre de 0,7 cm3/g. La coexistence de la mésoporosité et d’une macroporosité interconnectée de volume voisin est observée par MEB (Microscopie Électronique à Balayage) et MET (Microscopie Électronique en Transmission). En outre, l’organisation de la mésoporosité est partiellement maintenue comme le mettent en évidence la DRX (Diffraction des Rayons X) et la MET

Controlled motion of domain walls in submicron amorphous wires

© 2016 Author(s). Results on the control of the domain wall displacement in cylindrical Fe77.5Si7.5B15 amorphous glass-coated submicron wires prepared by rapid quenching from the melt are reported. The control methods have relied on conical notches with various depths, up to a few tens of nm, made in the glass coating and in the metallic nucleus using a focused ion beam (FIB) system, and on the use of small nucleation coils at one of the sample ends in order to apply magnetic field pulses aimed to enhance the nucleation of reverse domains. The notch-based method is used for the first time in the case of cylindrical ultrathin wires. The results show that the most efficient technique of controlling the domain wall motion in this type of samples is the simultaneous use of notches and nucleation coils. Their effect depends on wire diameter, notch depth, its position on the wire length, and characteristics of the applied pulse

Our first experience with cervical expandable cage for vertebral body reconstruction

Vertebral body reconstruction after corpectomy using expandable cage has become a common surgical procedure especially at thoracic level. The recent published papers describe the successful use of expandable cages for cervical vertebral body reconstruction. In this paper we present our first experience with expandable cervical cage in the reconstruction of the cervical spine in a patient with cervical spondylotic myelopathy (CSM)

Optimizing surgical techniques in extra-anatomical ilio-femoral bypasses

Scopul lucrării. Bypass-ul extraanatomic ilio-femural crossover este o procedura chirurgicala utilizată pentru revascularizarea segmentului aorto-femural, când intervențiile endovasculare nu sunt posibile, iar aplicarea unui bypass aorto sau ilio-femural este dificilă sau chiar imposibilă din cauza condițiilor tehnice sau a stării pacientului. Scopul este studierea rezultatelor precoce și tardive pentru favorizarea unor schimbări și implementarea unor gesturi tehnice în aplicarea bypass-urilor crossover ilio-femural, pentru a crea o geometrie cât mai fiziologică ce poate oferi o soluție durabilă pe termen lung. Materiale și metode. Pe parcursul anilor 2001-2022 au fost efectuate 142 bypass-uri crossover ilio-femurale. Rezultate. În perioada postoperatorie a fost un singur deces și s-au efectuat 3 amputații. Au fost analizate duplex scanările și CT angiografiile în primele 12 luni postoperatorii, pentru aprecierea altor leziuni aterosclerotice, care ar necesita revascularizare deschisă s-au endovasculară atît in bazinul recipient cât și cel donator. Totodată, a fost apreciata poziția și forma bypass-ului ce a dus la folosirea ulterioară a unor noi procedee tehnice ce diferă de cele descrise anterior. Concluzii. Optimizarea tehnicilor chirurgicale creând o geometrie cât mai fiziologică, excluderea maximală a angulărilor stenozante ale grefei poate oferi bypass-ului extraanatomic crossover ilio-femural o durabilitate îndelungată. Acest lucru poate favoriza creșterea frecvenței indicațiilor la folosirea bypass-urilor crossover ilio-femural.Aim of study. The extra-anatomic ilio-femoral crossover bypass is a surgical procedure used for revascularizing the aorto-femoral segment when endovascular interventions are not possible, and when applying an aorto- or ilio-femoral bypass is difficult or even impossible due to technical conditions or the patient's condition. The aim was to study the early and late outcomes to promote changes and implement technical gestures in the application of ilio-femoral crossover bypasses, aiming to create a more physiological geometry that can provide a durable long-term solution. Materials and methods. Between 2001 and 2022, a total of 142 ilio-femoral crossover bypasses were performed. Results. There was one death and three amputations in the postoperative period. Duplex scans and CT angiography were analyzed in the first 12 months postoperatively to assess other atherosclerotic lesions that would require open or endovascular revascularization in both the recipient and donor areas. Additionally, the position and shape of the bypass were evaluated, leading to the subsequent use of new technical procedures that differ from those previously described. Conclusions. Optimizing surgical techniques by creating a more physiological geometry and minimizing stenotic angles of the graft can provide the extra-anatomic ilio-femoral crossover bypass with long-lasting durability. This may increase the frequency of indications for using ilio-femoral crossover bypasses