Ineffective Controls on Capital Inflows Under Sophisticated Financial Markets: Brazil in the Nineties

We analyze the Brazilian experience in the 1990s to assess the effectiveness of controls on capital inflows in restricting financial inflows and changing their composition towards long term flows. Econometric exercises (VARs) showed that controls on capital inflows were effective in deterring financial inflows for only a brief period, from two to six months. The hypothesis to explain the ineffectiveness of the controls is that financial institutions performed several operations aimed at avoiding capital controls. To check this hypothesis, we conducted interviews with market players. We collected several examples of the financial strategies engineered to avoid the capital controls and invest in the Brazilian fixed income market. The main conclusion is that controls on capital inflows, while they may be desirable, are of very limited effectiveness under sophisticated financial markets.

Acute Intestinal Obstruction Due To Gallstone Ileus [abdome Agudo Por Obstrução Por Ileobiliar]

Objective: Small bowel obstruction (SBO) due to gallstones (gallstone ileus) is an uncommon complication of cholelithiasis, for which there is no defined surgical procedure. The objective of this study was to perform a systematic review of the history, available image exams and clinical approach to the diagnosis and treatment of gallstone ileus. Method: We conducted a retrospective study in a university hospital including all cases of SBO treated over a period of 23 years. According to the surgical treatment, the patients were divided into two groups: (1) enterolithotomy with posterior cholecystectomy (two-stage surgery); and (2) enterolithotomy, cholecystectomy and fistula closure (one-stage surgery). Results: Twelve patients were included in the study, including 11 females (91,6%), with a mean age of 72.2 years. All patients presented associated diseases, mainly arterial hypertension (75%). All except one patient had multiple SBO symptoms. Gallstone ileus diagnosis was made before laparotomy in six patients (50%). There were eight patients in group 1 and four in group 2, and the morbidity was, respectively, 33.3% and 8.3%. Overall mortality was 16.6% (one patient in each group). Conclusion: Gallstone ileus should be suspected in the elderly with SBO symptoms. Early diagnosis can reduce post-operative complications. Treatment is urgent laparotomy and the surgical approach must be individualized for each case. The majority of patients in this study were treated with enterolithotomy, with cholecystectomy being performed later in two symptomatic patients.404275280Martin, F., Intestinal obstruction due to gall-stones: With report of three successful cases (1912) Ann Surg., 55 (5), pp. 725-743Reisner, R.M., Cohen, J.R., Gallstone ileus: A review of 1001 reported cases (1994) Am Surg., 60 (6), pp. 441-446Lobo, D.N., Jobling, J.C., Balfour, T.W., Gallstone ileus: Diagnostic pittfalls and therapeutic successes (2000) J Clin Gastroenterol., 30 (1), pp. 72-76Hayes, N., Saha, S., Recurrent gallstone Ileus (2012) Clin Med Res., 10 (4), pp. 236-239Carrascosa, M.F., Riego-Martín, M.D., Salcines Caviedes, J.R., González Gutiérrez, P., Gallstone ileus (2012) BMJ Case Rep., , Feb 21;2012Rojas-Rojas, D.J., Martínez-Ordaz, J.L., Romero-Hernández, T., Biliary ileus: 10-years experience (2012) Cir Cir., 80 (3), pp. 228-232Tucker, A., Garstin, I., A peculiar cause of bowel obstruction (2013) Int J Surg Case Rep., 4 (5), pp. 473-476Halabi, W.J., Kang, C.Y., Ketana, N.K., Lafaro, K.J., Nguyen, V.K., Stamos, M.J., Surgery for gallstone ileus: A nationwide comparison of trends and outcomes (2013) Ann Surg., , jan 4 [Epub ahead of print]Pronio, A., Piroli, S., Caporilli, D., Ciamberlano, B., Coluzzi, M., Castellucci, G., Recurrent gallstone ileus: Case report and literature review (2013) G Chir., 34 (1-2), pp. 35-37McHado, M.A.C., Jukemura, J., Volpe, P., Abdo, E.E., Penteado, S., Bacchella, T., Fístulas biliares internas: Estudo de 13 casos e revisão da literatura (1995) Hos Clin Fac Med S Paulo., 50 (1), pp. 45-48Ayantunde, A.A., Agrawal, A., Gallstone Ileus: Diagnosis and management (2007) World J Surg., 31 (6), pp. 1292-1297Ravikumar, R., Williams, J.G., The operative management of gallstone ileus (2010) Ann R Coll Surg Engl., 92 (4), pp. 279-281Day, E.A., Marks, C., Gallstone ileus: Review of literature and presentation of thirty-four new cases (1975) Am J Surg., 129 (5), pp. 552-558Deitz, D.M., Standage, B.A., Pinson, C.W., McConnell, D.B., Krippaehne, W.W., Improving the outcome in gallstone ileus (1986) Am J Surg., 151 (5), pp. 572-576Bouveret, L., Stenose du pylore, adherent a la vesicule calculeuse (1896) Rev Med., 16, pp. 1-16Gajendran, M., Muniraj, T., Gelrud, A., A challenging case of gastric outlet obstruction (Bouveret's syndrome): A case report (2011) J Med Case Rep., 5, p. 497Costil, V., Jullès, M.C., Zins, M., Loriau, J., Bouveretś syndrome. An unusual localization of gallstone ileus (2012) J Visc Surg., 149 (4), pp. e284-e286Kasahara, Y., Umemura, H., Shiraha, S., Kuyama, T., Sakata, K., Kubota, H., Gallstone ileus. Review of 112 patients in the Japanese literature (1980) Am J Surg., 140 (3), pp. 437-440van Hillo, M., van der Vliet, J.A., Wiggers, T., Obertop, H., Terpstra, O.T., Greep, J.M., Gallstone obstruction of the intestine: An analysis of ten patients and a review of the literature (1987) Surgery., 101 (3), pp. 273-276Nuño-Guzmán, C.M., Arróniz-Jáuregui, J., Moreno-Pérez, P.A., Chávez-Solís, E.A., Esparza-Arias, N., Hernández-González, C.I., Gallstone ileus: One-stage surgery in a patient with intermittent obstruction (2010) World J Gastrointest Surg., 2 (5), pp. 172-176Clavien, P.A., Richon, J., Burgan, S., Rohner, A., Gallstone ileus (1990) Br J Surg., 77 (7), pp. 737-742Murphy, K.P., Kearney, D.E., Mc Laughlin, P.D., Maher, M.M., Complete radiological findings in gallstone ileus (2012) J Neurogastroenterol Motil., 18 (4), pp. 448-449Huang, S.T., Huang, M.Y., Gallstone ileus: A diagnostic challenge by plain radiography (2013) Emerg Med J., 30 (5), p. 370Lasson, A., Lorén, I., Nilsson, A., Nirhov, N., Nilsson, P., Ultrasonography in gallstone ileus: A diagnostic challenge (1995) Eur J Surg., 161 (4), pp. 259-263Mishin, I., Ghidirim, G., Zastavnitsky, G., Non-operative treatment for gall-stone ileus-a case report (2011) Pol Przegl Chir., 83 (4), pp. 223-226Conzo, G., Mauriello, C., Gambardella, C., Napolitano, S., Cavallo, F., Tartaglia, E., Gallstone ileus: One-stage surgery in an elderly patient: One-stage surgery in gallstone ileus (2013) Int J Surg Case Rep., 4 (3), pp. 316-318Mallipeddi, M.K., Pappas, T.N., Shapiro, M.L., Scarborough, J.E., Gallstone ileus: Revisiting surgical outcomes using National Surgical Quality Improvement Program data (2013) J Surg Res., , May 31. [Epub ahead of print]Beriner, S.D., Burson, L.C., One-stage repair for cholecyst-duodenal fistula and gallstone ileus (1965) Arch Surg., 90, pp. 313-316Jones, R., Broman, D., Hawkins, R., Corless, D., Twice recurrent gallstone ileus: A case report (2012) J Med Case Rep., 6 (1), p. 362Paiva-Coronel, G., Martínez-Ramos, D., Cosa-Rodríguez, R., Salvador-Sanchis, J.L., Íleo biliar. Abordaje asistido por laparoscopia (2010) Cir Esp., 87 (4), pp. 255-25

Chaotic Diffusion on Periodic Orbits: The Perturbed Arnol'd Cat Map

Chaotic diffusion on periodic orbits (POs) is studied for the perturbed Arnol'd cat map on a cylinder, in a range of perturbation parameters corresponding to an extended structural-stability regime of the system on the torus. The diffusion coefficient is calculated using the following PO formulas: (a) The curvature expansion of the Ruelle zeta function. (b) The average of the PO winding-number squared, $w^{2}$, weighted by a stability factor. (c) The uniform (nonweighted) average of $w^{2}$. The results from formulas (a) and (b) agree very well with those obtained by standard methods, for all the perturbation parameters considered. Formula (c) gives reasonably accurate results for sufficiently small parameters corresponding also to cases of a considerably nonuniform hyperbolicity. This is due to {\em uniformity sum rules} satisfied by the PO Lyapunov eigenvalues at {\em fixed} $w$. These sum rules follow from general arguments and are supported by much numerical evidence.Comment: 6 Tables, 2 Figures (postscript); To appear in Physical Review

Five Dimensional Cosmological Models in General Relativity

A Five dimensional Kaluza-Klein space-time is considered in the presence of a perfect fluid source with variable G and $\Lambda$. An expanding universe is found by using a relation between the metric potential and an equation of state. The gravitational constant is found to decrease with time as $G \sim t^{-(1-\omega)}$ whereas the variation for the cosmological constant follows as $\Lambda \sim t^{-2}$, $\Lambda \sim (\dot R/R)^2$ and $\Lambda \sim \ddot R/R$ where $\omega$ is the equation of state parameter and $R$ is the scale factor.Comment: 13 pages, 4 figures, accepted in Int. J. Theor. Phy

Non-linear QCD dynamics in two-photon interactions at high energies

Perturbative QCD predicts that the growth of the gluon density at high energies should saturate, forming a Color Glass Condensate (CGC), which is described in mean field approximation by the Balitsky-Kovchegov (BK) equation. In this paper we study the $\gamma \gamma$ interactions at high energies and estimate the main observables which will be probed at future linear colliders using the color dipole picture. We discuss in detail the dipole - dipole cross section and propose a new relation between this quantity and the dipole scattering amplitude. The total $\gamma \gamma$, $\gamma^{*} \gamma^{*}$ cross-sections and the real photon structure function $F_2^{\gamma}(x,Q^2)$ are calculated using the recent solution of the BK equation with running coupling constant and the predictions are compared with those obtained using phenomenological models for the dipole-dipole cross section and scattering amplitude. We demonstrate that these models are able to describe the LEP data at high energies, but predict a very different behavior for the observables at higher energies. Therefore we conclude that the study of $\gamma \gamma$ interactions can be useful to constrain the QCD dynamics.Comment: 11 pages, 5 figures. Version to be published in European Physical Journal

Multitarget Stool DNA Test Performance in an Average-Risk Colorectal Cancer Screening Population

INTRODUCTION: We set out to evaluate the performance of a multitarget stool DNA (MT-sDNA) in an average-risk colonoscopy-controlled colorectal cancer (CRC) screening population. MT-sDNA stool test results were evaluated against fecal immunochemical test (FIT) results for the detection of different lesions, including molecularly defined high-risk adenomas and several other tumor characteristics. METHODS: Whole stool samples (n = 1,047) were prospectively collected and subjected to an MT-sDNA test, which tests for KRAS mutations, NDRG4 and BMP3 promoter methylation, and hemoglobin. Results for detecting CRC (n = 7), advanced precancerous lesions (advanced adenoma [AA] and advanced serrated polyps; n = 119), and non-AAs (n = 191) were compared with those of FIT alone (thresholds of 50, 75, and 100 hemoglobin/mL). AAs with high risk of progression were defined by the presence of specific DNA copy number events as measured by low-pass whole genome sequencing. RESULTS: The MT-sDNA test was more sensitive than FIT alone in detecting advanced precancerous lesions (46% (55/119) vs 27% (32/119), respectively, P < 0.001). Specificities among individuals with nonadvanced or negative findings (controls) were 89% (791/888) and 93% (828/888) for MT-sDNA and FIT testing, respectively. A positive MT-sDNA test was associated with multiple lesions (P = 0.005), larger lesions (P = 0.03), and lesions with tubulovillous architecture (P = 0.04). The sensitivity of the MT-sDNA test or FIT in detecting individuals with high-risk AAs (n = 19) from individuals with low-risk AAs (n = 52) was not significantly different. DISCUSSION: In an average-risk screening population, the MT-sDNA test has an increased sensitivity for detecting advanced precancerous lesions compared with FIT alone. AAs with a high risk of progression were not detected with significantly higher sensitivity by MT-sDNA or FIT