Classical vs. Bayesian methods for linear system identification: point estimators and confidence sets

This paper compares classical parametric methods with recently developed Bayesian methods for system identification. A Full Bayes solution is considered together with one of the standard approximations based on the Empirical Bayes paradigm. Results regarding point estimators for the impulse response as well as for confidence regions are reported.Comment: number of pages = 8, number of figures =

Evidence for impurity-induced frustration in La2CuO4

Zero-field muon spin rotation and magnetization measurements were performed in La2Cu{1-x}MxO4, for 0<x< 0.12, where Cu2+ is replaced either by M=Zn2+ or by M=Mg2+ spinless impurity. It is shown that while the doping dependence of the sublattice magnetization (M(x)) is nearly the same for both compounds, the N\'eel temperature (T_N(x)) decreases unambiguously more rapidly in the Zn-doped compound. This difference, not taken into account within a simple dilution model, is associated with the frustration induced by the Zn2+ impurity onto the Cu2+ antiferromagnetic lattice. In fact, from T_N(x) and M(x) the spin stiffness is derived and found to be reduced by Zn doping more significantly than expected within a dilution model. The effect of the structural modifications induced by doping on the exchange coupling is also discussed.Comment: 4 pages, 4 figure

Monopole-limited nucleation of magnetism in Eu2_{2}Ir2_{2}O7_{7}

We present an in-depth analysis of muon-spin spectroscopy measurements of Eu$_{2}$Ir$_{2}$O$_{7}$ under the effect of the Eu$_{1-x}$Bi$_{x}$ isovalent and diamagnetic substitution as well as of external pressure. Our results evidence an anomalously slow increase of the magnetic volume fraction upon decreasing temperature only for stoichiometric Eu$_{2}$Ir$_{2}$O$_{7}$, pointing towards highly unconventional properties of the magnetic phase developing therein. We argue that magnetism in Eu$_{2}$Ir$_{2}$O$_{7}$ develops based on the nucleation of magnetic droplets at $T_{N}$, whose successive growth is limited by the need of a continuous generation of magnetic hedgehog monopoles.Comment: 9 pages, 4 figure

Tuning of competing magnetic and superconducting phase volumes in LaFeAsO$_0.945F_0.055 by hydrostatic pressure

The interplay between magnetism and superconductivity in LaFeAsO_0.945F_0.055 was studied as a function of hydrostatic pressure up to p~2.4GPa by means of muon-spin rotation (\muSR) and magnetization measurements. The application of pressure leads to a substantial decrease of the magnetic ordering temperature T_N and a reduction of the magnetic phase volume and, at the same time, to a strong increase of the superconducting transition temperature T_c and the diamagnetic susceptibility. From the volume sensitive \muSR measurements it can be concluded that the superconducting and the magnetic areas which coexist in the same sample are inclined towards spatial separation and compete for phase volume as a function of pressure.Comment: 4 pages, 4 figure

Seroprevalence of Neospora caninum infection in cattle from Pereira, Colombia

There are over 25.6 million cattle heads in Colombia being the fourth-highest herd in Latin America. This study aimed to describe the seroprevalence of Neospora caninum in cattle from 25 rural farms at Pereira municipality, Risaralda Department, which has a total bovine population of 43,508 animals. A cross-sectional observational study was performed in beef and dairy herds during 2017–2018. A total of 325 animals in 25 herds, with 13 animals per herd, were sampled. A commercial competitive ELISA (cELISA) kit was used to detect N. caninum antibodies. Associated risk factors were analyzed in two different levels: individual animals and herds. For all the independent variables, chi-square (χ2) and Fisher tests were used to assess associations and significance. The overall estimated seropositivity was 20.6% (95%CI 16.2%–25.0%). The seroprevalence by herds was 92.0% ranging from 0.0% to 46.2%. Noteworthy, beef herds had significantly (p = 0.0107) higher seropositivity (50% of them above 35% of seropositivity) compared with those for milk purposes (4.8%) (OR = 20.0; 95%CI 1.2–331.0). Other risk factors were not significantly (p ≥ 0.05) associated with N. caninum seropositivity. Bovine neosporosis may be associated with abortions in both beef and dairy Colombian farms. More studies about the epidemiology, associated factors and consequences, as well as on tools for better diagnosis of bovine abortion, including histopathology and other ancillary tests, should be performed.Fil: Idarraga Bedoya, Samuel E.. Fundación Universitaria Autónoma de las Américas. Facultad de Medicina Veterinaria y Zootecnia; ColombiaFil: Álvarez Chica, Jaime. Fundación Universitaria Autónoma de las Américas. Facultad de Medicina Veterinaria y Zootecnia; ColombiaFil: Bonilla Aldana, D. Katterine. Universidad Tecnológica de Pereira; Colombia. Fundación Universitaria Autónoma de las Américas; ColombiaFil: Moore, Dadin Prando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Innovación para la Producción Agropecuaria y el Desarrollo Sostenible - Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce. Instituto de Innovación para la Producción Agropecuaria y el Desarrollo Sostenible; ArgentinaFil: Rodríguez Morales, Alfonso J.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Innovación para la Producción Agropecuaria y el Desarrollo Sostenible - Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce. Instituto de Innovación para la Producción Agropecuaria y el Desarrollo Sostenible; Argentina. Universidad Tecnológica de Pereira; Colombia. Fundación Universitaria Autónoma de las Américas; Colombi

Emergency Surgery in the Elderly: Could Laparoscopy Be Useful in Frailty? A Single-Center Prospective 2-Year Follow-Up in 120 Consecutive Patients

Background: the general population is aging across the world. Therefore, even surgical interventions in the elderly—in particular those involving emergency surgical admissions—are becoming more frequent. The elderly population is often frail (in multiple physiological systems, this is often defined as age-related cumulative decline). This study involved a 2-year follow-up evaluation of frail elderly patients treated with urgent surgical intervention at Santa Maria Regina della Misericordia Hospital, General Surgery Department, in Adria (Italy). Method: a prospective, single-center, 2-year follow-up study of 120 patients &gt;65 years old, treated at our department for surgical abdominal emergencies. We considered co-morbidities (ASA—American Society of Anesthesiologists Physical Status Classification System—score), type of surgery (laparoscopy, laparotomy or converted), frailty score, mortality, and complications at 30 days and at 2 years. Conclusions: 70 (58.4%) patients had laparoscopy, 49 (40.8) had laparotomy, and in 1 (0.8%) case, surgery was converted from laparoscopy to laparotomy. Mortality strictly depends on the type of surgery (laparotomy vs. laparoscopy), complications during recovery, and a lower Fried frailty criteria score, on average. The long-term follow-up can be a useful tool to highlight a safer surgical approach, such as laparoscopy, in frail elderly patients. We consider the laparoscopic approach feasible in emergency situations, with similar or better outcomes than laparotomy, especially in frail elderly patients

Genetic diversity of Tibraca limbativentris Stål (Hemiptera: Pentatomidae) of Santa Catarina and Rio Grande do Sul, Brazil, using RAPD

O trabalho objetivou testar protocolos de extração de DNA e caracterizar populações de Tibraca limbativentris, Stål, importante inseto-praga do arroz. Os insetos foram coletados em Joinville, Rio do Oeste e Turvo, em Santa Catarina, e Agudo, Uruguaiana, Pelotas e Palmares do Sul, no Rio Grande do Sul. Testaram-se seis protocolos de extração de DNA citados na literatura, e um novo protocolo adequado à espécie em questão. DNA de dez indivíduos de cada população foi extraído usando o melhor protocolo e reações de RAPD foram realizadas com dez iniciadores. O novo protocolo mostrou os melhores resultados e foi utilizado nas reações de PCR, que geraram 151 bandas polimórficas, permitindo acessar diferenças genéticas entre todas as populações; não ocorreram indivíduos de uma população agrupados com os de outra. A maior similaridade intrapopulacional foi encontrada em Uruguaiana (22%), e a menor em Palmares do Sul (50%), também a população mais divergente das demais. O valor Gst foi 0,5215, e de Nm 0,4588; esses valores refletem a pouca similaridade entre as populações. O menor Nm foi apresentado quando Palmares do Sul e Pelotas foram incluídos nas comparações, em consonância com a maior divergência apresentada por essas populações em relação às outras. Não se observou relação entre a distância geográfica e a similaridade genética das populações, o que refletirá o modelo de dispersão de T. limbativentris, ainda desconhecido. Estudos explorando as estratégias de dispersão da espécie poderiam ajudar no entendimento da distribuição do inseto, evidenciando qual a principal fonte de variabilidade genética.The work was carried out to test DNA extraction protocols and to characterize populations of Tibraca limbativentris Stål, an important rice insect-pest. Insects were collected in Joinville, Rio do Oeste and Turvo, in Santa Catarina State, and Agudo, Uruguaiana, Pelotas and Palmares do Sul, in Rio Grande do Sul State, and six literature-referenced protocols, besides a new one, were tested. DNA from ten individuals of each population was extracted using the best protocol and RAPD reactions were carried out with ten initiators. The new protocol showed the best results and was used in the PCR reactions, that generated 151 polymorphic bands, allowing to access genetic differences among all the populations; no individuals from one population were clustered with individuals from another. The largest intrapopulacional similarity was found in Uruguaiana (22%), and the smallest in Palmares do Sul (50%), which was also the most divergent population in relation to the others. The Gst was 0.5215, and the Nm was 0.4588; these values reflect the low similarity between the populations. The smallest genic flow was obtained when Palmares do Sul and Pelotas were included in the comparisons, in accordance with the largest divergence of these two populations in relation to the others. There was no significant relation between geographic distance and genetic similarity, which can reflect unknown model of dispersion of T. limbativentris. New studies exploring the species dispersion strategies may help to understand the insect distribution and to unveil the main factors linked to the genetic variability within and between populations.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Ninety-day oral toxicity assessment of an alternative biopolymer for controlled release drug delivery systems obtained from cassava starch acetate.

The large consumption of biodegradable films from cassava starch acetate (FCSA) as ingredients in food and pharmaceutical products requires the assessment of the possible toxicity of these products. The aim of this study was to investigate the toxicity of biodegradable film from cassava starch acetate after oral exposure of Wistar rats for 90 days. The amount of food consumed and the body weight were weekly monitored. Blood and urine samples were obtained for the assessment of serum parameters and renal function. Histopathological analyses in target organs were also performed. No evidence of clinical toxicity in hematological, biochemical, or renal parameters in the FCSA-treated animals was found. In addition, relative organ weight and histopathological evaluations did not differ between groups treated with FCSA and control. Data obtained suggest that the subchronic exposure to FCSA does not cause obvious signs of toxicity inWistar rats, indicating possible safety of this biofilm