1,711 research outputs found

    Multiple plasmon resonances in naturally-occurring multiwall nanotubes: infrared spectra of chrysotile asbestos

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    Chrysotile asbestos is formed by densely packed bundles of multiwall hollow nanotubes. Each wall in the nanotubes is a cylindrically wrapped layer of Mg3Si2O5(OH)4Mg_3 Si_2 O_5 (OH)_4. We show by experiment and theory that the infrared spectrum of chrysotile presents multiple plasmon resonances in the Si-O stretching bands. These collective charge excitations are universal features of the nanotubes that are obtained by cylindrically wrapping an anisotropic material. The multiple plasmons can be observed if the width of the resonances is sufficiently small as in chrysotile.Comment: 4 pages, 5 figures. Revtex4 compuscript. Misprint in Eq.(6) correcte

    Bayesian evidence for two companions orbiting HIP 5158

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    We present results of a Bayesian analysis of radial velocity (RV) data for the star HIP 5158, confirming the presence of two companions and also constraining their orbital parameters. Assuming Keplerian orbits, the two-companion model is found to be e^{48} times more probable than the one-planet model, although the orbital parameters of the second companion are only weakly constrained. The derived orbital periods are 345.6 +/- 2.0 d and 9017.8 +/- 3180.7 d respectively, and the corresponding eccentricities are 0.54 +/- 0.04 and 0.14 +/- 0.10. The limits on planetary mass (m \sin i) and semimajor axis are (1.44 +/- 0.14 M_{J}, 0.89 +/- 0.01 AU) and (15.04 +/- 10.55 M_{J}, 7.70 +/- 1.88 AU) respectively. Owing to large uncertainty on the mass of the second companion, we are unable to determine whether it is a planet or a brown dwarf. The remaining `noise' (stellar jitter) unaccounted for by the model is 2.28 +/- 0.31 m/s. We also analysed a three-companion model, but found it to be e^{8} times less probable than the two-companion model.Comment: 5 pages, 4 figures, 3 tables. Added a couple of figures showing the residuals after one and two companion fits. Accepted for publication in MNRAS Letter

    Crystallization, data collection and data processing of maltose-binding protein (MalE) from the phytopathogen Xanthomonas axonopodis pv. citri

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    Maltose-binding protein is the periplasmic component of the ABC transporter responsible for the uptake of maltose/maltodextrins. The Xanthomonas axonopodis pv. citri maltose-binding protein MalE has been crystallized at 293 Kusing the hanging-drop vapour-diffusion method. The crystal belonged to the primitive hexagonal space group P6_122, with unit-cell parameters a = 123.59, b = 123.59, c = 304.20 Å, and contained two molecules in the asymetric unit. It diffracted to 2.24 Å resolution

    Staging of plastic operations and multiple surgery procedures after massive weight loss

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    Catedra de chirurgie nr. 1 „Nicolae Anestiadi”, Catedra de chirurgie nr.4, USMF „Nicolae Testemițanu”, Chișinău, Republica Moldova, Conferința stiințifică „Nicolae Anestiadi – nume etern al chirurgiei basarabene” consacrată centenarului de la nașterea profesorului Nicolae Anestiadi 26 august 2016Introducere. Pierderea masivă a masei corporale (PMMC) se asociază cu apariția unui exces esențial de piele, falduri dermice în zona abdominală și alte regiuni ale corpului uman. Acești pacienți solicită, de obicei, mai multe procedee chirurgicale pentru a reduce perioada de recuperare. Scopul. Evaluarea operațiilor simultane și a criteriilor de siguranță în chirurgia plastica după PMMC. Material și metode. Am realizat 81 de operații plastice la 39 de pacienți cu PMMC. Am efectuat 24 operații simultane și 57 în etape. 29 de pacienți au avut PMMC după operații bariatrice (bypass gastric (27), "gastric sleeve" (2), iar 10 pacienți după un tratament dietetic și comportamental. S-au efectuat următoarele procedee de chirurgie plastică: abdomenoplastia "fleur de lys", circumferențială sau extinsă; hernioplastia, brahioplastia; torsoplastia, mamoplastia, liftingul de coapse și fesier, liftingul facial și blefaroplastia. Două echipe de chirurgi au efectuat operațiile simultane în scopul de a reduce timpul de operare, riscurile și timpul de recuperare. Rezultate. Cele mai frecvente operații simultane au fost abdominoplastia "Fleur de Lys" cu hernioplastie sau cu mamoplastie, liftingul intern al coapsei cu brahioplastia. Concluzii. Operațiile simultane nu sunt asociate cu o rată mai mare a complicațiilor postoperatorii. Etapizarea operațiilor oferă o alternativă bună pentru pacienții cu IMC> 30kg/m2, sau pentru pacienți, care nu pot efectua operații simultane din alte motive.Introduction. Massive weight loss (MWL) is associated with the appearance of an essential skin excess, dermal folds in the abdominal area and other parts of human body. These patients usually want to perform multiple surgical procedures to reduce the recovery period. Purpose. Assessment of simultaneous operations and safety criteria in plastic surgery after MWL. Materials and methods. We performed 81 plastic operations on 39 patients with MWL. We done 24 simultaneous operations and 57 in stages respectively. Massive body mass lost 29 patients after bariatric surgery (gastric bypass (27), "gastric sleeve" (2), and 10 patients have lost weight through dietary and behavioral treatment. The following plastic surgery procedures were made: "fleur de lys" abdominoplasty, circumferential or extended abdominoplasty; hernioplasty, brahioplasty; torsoplasty, mammoplasty; thighs and buttock lift; internal thigh lift, face lift and blepharoplasty. Two teams of surgeons performed simultaneous operations in order to reduce the operating time, risk and recovery time. Results. The most common combination in simultaneous operations were "Fleur de Lys "abdominoplasty with hernioplasty or mammoplasty, internal thigh lift with upper arm lift. No major complications were recorded. Conclusion. Simultaneous operations are not associated with a higher rate of postoperative complications. Staging operations provides a good alternative for patients with BMI> 30kg/m2, or for patients who cannot be made simultaneous operations for other reasons

    Analysis of Groyne Placement on Minimising River Bank Erosion

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    AbstractBank erosion is the wearing away of the banks of a stream or river. Impacts of river bank erosion are multifarious: social, economic, health, education and sometimes political. Groynes are structures constructed in rivers to protect the shore. Groynes are generally made of wood, concrete, or rock piles etc. In the present study coir geotextiles in the form of cocologs are used as the groynes to make the groyne more ecofriendly. Study mainly concentrates on analysing the effects of placing groynes at different angles from 450 to 1350 and to find the most effective arrangement for minimising the erosion. Results indicate that cocolog-groynes are effective in minimizing the erosion and protecting the bank. Maximum protection is observed for groyne angle of 1350

    Serializing the Parallelism in Parallel Communicating Pushdown Automata Systems

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    We consider parallel communicating pushdown automata systems (PCPA) and define a property called known communication for it. We use this property to prove that the power of a variant of PCPA, called returning centralized parallel communicating pushdown automata (RCPCPA), is equivalent to that of multi-head pushdown automata. The above result presents a new sub-class of returning parallel communicating pushdown automata systems (RPCPA) called simple-RPCPA and we show that it can be written as a finite intersection of multi-head pushdown automata systems

    Detecting extrasolar planets from stellar radial velocities using Bayesian evidence

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    Stellar radial velocity (RV) measurements have proven to be a very successful method for detecting extrasolar planets. Analysing RV data to determine the parameters of the extrasolar planets is a significant statistical challenge owing to the presence of multiple planets and various degeneracies between orbital parameters. Determining the number of planets favoured by the observed data is an even more difficult task. Bayesian model selection provides a mathematically rigorous solution to this problem by calculating marginal posterior probabilities of models with different number of planets, but the use of this method in extrasolar planetary searches has been hampered by the computational cost of the evaluating Bayesian evidence. Nonetheless, Bayesian model selection has the potential to improve the interpretation of existing observational data and possibly detect yet undiscovered planets. We present a new and efficient Bayesian method for determining the number of extrasolar planets, as well as for inferring their orbital parameters, without having to calculate directly the Bayesian evidence for models containing a large number of planets. Instead, we work iteratively and at each iteration obtain a conservative lower limit on the odds ratio for the inclusion of an additional planet into the model. We apply this method to simulated data-sets containing one and two planets and successfully recover the correct number of planets and reliable constraints on the orbital parameters. We also apply our method to RV measurements of HD 37124, 47 Ursae Majoris and HD 10180. For HD 37124, we confirm that the current data strongly favour a three-planet system. We find strong evidence for the presence of a fourth planet in 47 Ursae Majoris, but its orbital period is suspiciously close to one year, casting doubt on its validity. For HD 10180 we find strong evidence for a six-planet system.Comment: 12 pages, 6 figures, 12 tables. Added results obtained by applying the method to 47 Ursae Majoris and HD 10180. Accepted for publication in MNRA

    Particular form of simultaneous pancreas and liver toxic damage

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    USMF “N. Testemițanu”, Clinica Chirurgie “Sf. Arh. Mihail”, 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 2011Studiul vizează 10 cazuri, observate în SCM ”Sf. Arh. Mihail” pe perioada ultimilor 10 ani. Toți sunt spitalizați în secția ATI cu manifestări clinicoparaclinice de insuficiență hepatică acută; antecedente de băutori și cu afecțiuni hepatice cronice (hepatita cronică 2 cazuri, ciroza hepatică -8). Date pentru pancreatita acută căutate intenționat absente, amilaza sanguine cifre joase/ absentă, date EUS (10 caz. ), cât și CT (2 caz.) fără modificări de structură. Evolutțe gravă, icter, uremie, hipoprotrombinemie, trasamilazemie, ulterior MODS avansat. Deces în mediu la ziua a 8 . Necroptic – asociație de ciroză hepatică cu pancreatită acută necrotică în toate cazurile. Expansie parapancreatică absentă. În acest context de afectare panceatica directă au fost studiate și 55 acte medico-legale de deces subit (anii 2004-2006) cu diagnostic – pancreonecroză hemoragică. Rezultatul ulterior a alcoolemiei arată a fi prezent în 39 cazuri ( 71%), până la 3% - 23 cazuri, peste 3% -15 cazuri. Concluzie: 1. Posibilitatea afectării toxice concomitente a ficatului și pancreasului este o realitate clinică. 2. Clinico - paraclinic predomină insuficiența hepatică acută, manifestările pancreatice fiind minime. 3. PA are o evoluție necrotică de la început, fără răspândire peripancreatică și deasemenea fără complicații chirurgicale.The study included 10 cases observed in the SCM ” St. Arch. Michael’’ during the last 10 years. All are hospitalized in the ATI department with clinical manifestations of acute liver failure laboratory, and drinkers with a history of chronic liver disease (2 cases, chronic hepatitis, and liver cirrhosis 8). Data for acute pancreatitis intentionally sought missing digits blood amylase low / absent, EUS data (10 cases.) and CT (two cases.) no modifications of structure. Charts severe jaundice, uremia, hipoprotrombinemy, trasamilazemy subsequently advanced MODS. Death occurs in the average at day 8. Necroptic - association of cirrhosis with acute necrotic pancreatitis in all cases. Parapancreatic expansion is missing. In this context panceatic direct damage and 55 acts have been studied forensic sudden death (2004-2006) with diagnosis - hemorrhagic pancreatic necrosis. Result of alcohol tests later shown to be present in 39 cases (71%), up to 3% - 23 cases over 3%-15 cases. Conclusion: 1. the possibility of toxic damage to liver and pancreas simultaneous is a clinical reality. 2. Clinical - Acute liver failure prevails paraclinical, pancreatic manifestations were minimal. 3. PA has a necrotic evolution from the beginning, and also without peripancreatic spread visa without surgical complications
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