Nonlinear dynamics of beta induced Alfv\'en eigenmode driven by energetic particles

Nonlinear saturation of beta induced Alfv\'en eigenmode, driven by slowing down energetic particles via transit resonance, is investigated by the nonlinear hybrid magnetohyrodynamic gyro-kinetic code (XHMGC). Saturation is characterized by frequency chirping and symmetry breaking between co- and counter-passing particles, which can be understood as the the evidence of resonance-detuning. The scaling of the saturation amplitude with the growth rate is also demonstrated to be consistent with radial resonance detuning due to the radial non-uniformity and mode structure

A Giant Sample of Giant Pulses from the Crab Pulsar

We observed the Crab pulsar with the 43-m telescope in Green Bank, WV over a timespan of 15 months. In total we obtained 100 hours of data at 1.2 GHz and seven hours at 330 MHz, resulting in a sample of about 95000 giant pulses (GPs). This is the largest sample, to date, of GPs from the Crab pulsar taken with the same telescope and backend and analyzed as one data set. We calculated power-law fits to amplitude distributions for main pulse (MP) and interpulse (IP) GPs, resulting in indices in the range of 2.1-3.1 for MP GPs at 1.2 GHz and in the range of 2.5-3.0 and 2.4-3.1 for MP and IP GPs at 330 MHz. We also correlated the GPs at 1.2 GHz with GPs from the Robert C. Byrd Green Bank Telescope (GBT), which were obtained simultaneously at a higher frequency (8.9 GHz) over a span of 26 hours. In total, 7933 GPs from the 43-m telescope at 1.2 GHz and 39900 GPs from the GBT were recorded during these contemporaneous observations. At 1.2 GHz, 236 (3%) MP GPs and 23 (5%) IP GPs were detected at 8.9 GHz, both with zero chance probability. Another 15 (4%) low-frequency IP GPs were detected within one spin period of high-frequency IP GPs, with a chance probability of 9%. This indicates that the emission processes at high and low radio frequencies are related, despite significant pulse profile shape differences. The 43-m GPs were also correlated with Fermi gamma-ray photons to see if increased pair production in the magnetosphere is the mechanism responsible for GP emission. A total of 92022 GPs and 393 gamma-ray photons were used in this correlation analysis. No significant correlations were found between GPs and gamma-ray photons. This indicates that increased pair production in the magnetosphere is likely not the dominant cause of GPs. Possible methods of GP production may be increased coherence of synchrotron emission or changes in beaming direction.Comment: 33 pages, 10 figures, 6 tables, accepted for publication in Ap

Pole dynamics for the Flierl-Petviashvili equation and zonal flow

We use a systematic method which allows us to identify a class of exact solutions of the Flierl-Petvishvili equation. The solutions are periodic and have one dimensional geometry. We examine the physical properties and find that these structures can have a significant effect on the zonal flow generation.Comment: Latex 40 pages, seven figures eps included. Effect of variation of g_3 is studied. New references adde

Causes of unfavorable evolution of pancreatic trauma

Catedra de chirurgie nr. 1 “Nicolae Anestiadi”, Universitatea de Stat de Medicină și Farmacie ”Nicolae Testemițanu”, IMSP Institutul de Medicină Urgentă, Laboratorul Chirurgie Hepato-Pancreato-Biliară, Chișinău, Republica Moldova, Al XIII-lea Congres al Asociației Chirurgilor „Nicolae Anestiadi” și al III-lea Congres al Societății de Endoscopie, Chirurgie miniminvazivă și Ultrasonografie ”V.M.Guțu” din Republica MoldovaIntroducere: Rezultatele tratamentului chirurgical în traumatismul pancreatic (TP) nu sunt considerate satisfăcătoare din cauza persistenței mortalității cu o frecvență de 13,8-39,4%. Complicația specifică - pancreatita acută posttraumatică (PAPT) se dezvoltă practic după fiecare intervenție chirurgicală cu o frecvența de 25,9-85,7%. Scopul: Analiza cauzelor rezultatelor nefavorabile în tratamentul TP. Material și metode: S-au studiat retrospectiv rezultatele tratamentului chirurgical a 70 pacienți cu TP, și anume complicațiile postoperatorii și letalitatea specifică și nespecifică. Criteriile de includere: vârsta >18 ani și intervenția urgentă; de excludere - decedații 24 ore . Rezultate: În perioada postoperatorie la 48 pacienți au fost depistate complicații specifice, cele mai frecvente fiind pancreonecroza (23 pts), PAPT interstițială și fistulele pancreatice (respectiv câte 11 pts.). Peste 48 ore au decedat 14 pacienți. Letalitatea specifică a constituit 9,6%, nespecifică - 12,4%. În dependență de intervențiile efectuate, complicațiile specifice și letalitatea au fost mai scăzute la drenarea închisă a BO, intervențiile fiind efectuate în gr. I-II de leziune vs gr. III-V (62,2% și 5,3% vs 85,7% și 42,9%). La prezența hemoragiilor s-a stabilit, că suturarea ermetică a țeusuturilor pancreatice a majorat frecvența complicațiilor specifice și letalității vs suturarea neermetică (91,6% și 16,3% vs 60,8% și 9,2%). Administrarea tratamentul medicamentos pentru PAPT, mai ales cu includerea Sandostatinei a diminuat rata complicațiilor și letalității specifice în comparație cu neadministrarea preparatului (56,5% și 4,7% vs 83,2% și 12,3%). Concluzii: Evoluția nefavorabilă a TP este urmare a suturării ermetice a plăgilor, drenării incorecte a BO și omiterii profilaxiei medicamentoase.Background: The outcomes of the surgical treatment in pancreatic trauma (PT) are not considered satisfactory because of the persistence of a high mortality rate, reaching 13,8-39,4%. The specific complication is posttraumatic acute pancreatitis (PTAP) that it develops after each surgical intervention in practice with a frequency between 25,9 and 85,7%. Aim of the study: Analysis of causes unfavorable results (outcomes) in the treatment of pancreatic treatment Methods and materials: The results of surgical treatment were retrospectively evaluated in 70 patients with pancreatic trauma according to (by) postinterventional complications and specific/non-specific lethality. Inclusion criteria were: age greater than 18 years and emergency surgery. Exclusion criteria were: died patients within 48 hours after hospitalization and hospitalization greater than 24 hours. Results: During the postoperative period specific complications were found in 48 patients, the most common being pancreonecrosis in 23 patients, PTAP interstitial and pancreatic fistula in 11 patients, respectively. After 48 hours 14 patients died. Specific lethality was 9.6% and non-specific lethality - 12.4%. Depending on the performed intervention, specific complications and lethality were lowered to the closed drainage of omental bursa (OB), the interventions being made in gr. I-II of lesions vs gr. III-V (62,2% and 5,3% vs 85,7% and 42,9%). In the presence of haemorrhages, it was established that the hermetic suture of pancreatic tissues increased the frequency of specific complications and lethality versus non-ermetic suture (91,6% și 16,3% vs 60,8% și 9,2%). Administration of drug therapy in PTAP, especially with the including of Sandostatin, reduced the rate of complications and specific lethality instead of non-administration of the medicine (56,5% și 4,7% vs 83,2% și 12,3%). Conclusions: The unfavorable evolution of PT is due to ermetic suturing of wounds, incorrect drainage of OB and omission of drug prophylaxis

Giant buttock lipoma whith compression of the sciatic nerve (case report)

Catedra Chirurgie nr.1 “N.Anestiadi”, Laboratorul Chirurgie Hepato-Pancreato-Biliară, USMF „Nicolae Testemiţanu”, Institutul de Medicină Urgentă, Chişinău, Republica Moldova, Al XII-lea Congres al Asociației Chirurgilor „Nicolae Anestiadi” din Republica Moldova cu participare internațională 23-25 septembrie 2015Introducere: Lipoamele reprezintă un grup heterogen de tumori mezenchimale benigne, cu localizare frecventă în regiunea spatelui, gâtului, feselor și mai rar în regiunea feţei. Pot apărea la orice vârstă, dar cu o frecvenţă de 3-4 ori mai mare la femei; dimensiunile constituind 1-5 cm. Însă în literatura de specialitate sunt descrise cazuri, când tumoarea atinge dimensiuni și greutate enormă, care se poate complica cu comprimarea vaselor și nervilor, cu apariţia a diverse simptome patologice. Caz clinic: Prezentăm cazul tratamentului unui pacient cu lipom gigant al regiunii fesiere drepte cu comprimarea nervului sciatic. Pacienta L, 63 ani, a fost spitalizată cu acuze la prezenţa unei formaţiuni gigante în regiunea fesieră dreaptă, dureri intense și șchiopătare în timpul mersului. La examenul primar se determină o tumoră cu dimensiuni 18,0x15,0 cm, dureroasă la palpare. S-a efectuat examenul ultrasonor și radiografia regiunii fesiere cu rezultate de colecţie lichidiană și, respectiv, neaderare de oasele bazinului. Puncţia tumorii, efectuată preoperator, denotă absenţa datelor de conţinut lichidian. Intraoperator s-a depistat un lipom gigant cu dimensiunile de 18,0x24,0 cm, localizat sub mușchiul gluteus maximus și aderat de nervul sciatic. A fost mobilizată și înlăturată tumora împreună cu capsula. Greutatea a constituit 2950 gr. Examenul histologic: lipomă. Finisarea intervenţiei prin drenarea și suturarea plăgii. Externarea la a 7-a zi cu absenţa durerilor și șchiopătării. Concluzie: Lipoamele gigante ale fesei provoacă probleme estetice și de mers, iar diagnosticul intraoperator și exereza chirurgicală a acestora readuc pacientul la activitate cotidiană obișnuită.Introduction: Lipomas represent a heterogeneous group of benign mesenchymal tumors, with frequent location in the back region, neck, buttocks, and rarely in the facial region. They can occur at any age, with a frequency of 3-4 times higher in women, the dimensions being of 1-5 cm. However, in the literature there are described cases, when the tumor reaches enormous size and weight, which may complicate with the compressing of vessels and nerves, and respectively with the appearance of various pathological symptoms. Clinical case: We present the treatment of patient with giant lipoma of right buttock region with high compression of the sciatic nerve. Patient L, female, 63 year-old was hospitalized with complaints of the presence of a giant formation in right buttock, intense pain and lameness while walking. The primary examination determined a tumor of size 18.0x15.0 cm, painful on palpation. Ultrasound examination and radiography of buttock region has been performed with the result of effusion, nonadherent to pelvic bones. Puncture of the tumor, performed preoperatively, shows no fluid content data. Intraoperative was found a giant lipoma of size 18.0x24.0 cm, located under the gluteus maximus muscle and joined the large sciatic nerve. The tumor was mobilized and removed along with the capsule. Her weight constituted 2950 g. Histological examination: lipoma. The intervention has been finished by draining and suturing the wound. The patient was discharged at the 7-th day with no pain and lameness. Conclusion: Giant lipoma of buttock causes aesthetic problems and walking disorders, and intraoperative diagnosis and surgical excision bring the patient to normal daily activities

Rare Events Statistics in Reaction--Diffusion Systems

We develop an efficient method to calculate probabilities of large deviations from the typical behavior (rare events) in reaction--diffusion systems. The method is based on a semiclassical treatment of underlying "quantum" Hamiltonian, encoding the system's evolution. To this end we formulate corresponding canonical dynamical system and investigate its phase portrait. The method is presented for a number of pedagogical examples.Comment: 12 pages, 6 figure

On the analyticity and Gevrey class regularity up to the boundary for the Euler Equations

We consider the Euler equations in a three-dimensional Gevrey-class bounded domain. Using Lagrangian coordinates we obtain the Gevrey-class persistence of the solution, up to the boundary, with an explicit estimate on the rate of decay of the Gevrey-class regularity radius

Magnetic Nanoparticle Systems for Nanomedicine—A Materials Science Perspective

Iron oxide nanoparticles are the basic components of the most promising magneto-responsive systems for nanomedicine, ranging from drug delivery and imaging to hyperthermia cancer treatment, as well as to rapid point-of-care diagnostic systems with magnetic nanoparticles. Advanced synthesis procedures of single- and multi-core iron-oxide nanoparticles with high magnetic moment and well-defined size and shape, being designed to simultaneously fulfill multiple biomedical functionalities, have been thoroughly evaluated. The review summarizes recent results in manufacturing novel magnetic nanoparticle systems, as well as the use of proper characterization methods that are relevant to the magneto-responsive nature, size range, surface chemistry, structuring behavior, and exploitation conditions of magnetic nanosystems. These refer to particle size, size distribution and aggregation characteristics, zeta potential/surface charge, surface coating, functionalization and catalytic activity, morphology (shape, surface area, surface topology, crystallinity), solubility and stability (e.g., solubility in biological fluids, stability on storage), as well as to DC and AC magnetic properties, particle agglomerates formation, and flow behavior under applied magnetic field (magnetorheology)