444 research outputs found
The matrix Kadomtsev--Petviashvili equation as a source of integrable nonlinear equations
A new integrable class of Davey--Stewartson type systems of nonlinear partial
differential equations (NPDEs) in 2+1 dimensions is derived from the matrix
Kadomtsev--Petviashvili equation by means of an asymptotically exact nonlinear
reduction method based on Fourier expansion and spatio-temporal rescaling. The
integrability by the inverse scattering method is explicitly demonstrated, by
applying the reduction technique also to the Lax pair of the starting matrix
equation and thereby obtaining the Lax pair for the new class of systems of
equations. The characteristics of the reduction method suggest that the new
systems are likely to be of applicative relevance. A reduction to a system of
two interacting complex fields is briefly described.Comment: arxiv version is already officia
Estudo comparativo de delineamentos experimentais para estimativas de parâmetros genéticos em erva-mate Ilex paraguariensis A. St. Hil..
O presente trabalho teve por objetivo comparar a eficiência do látice em relação aos delineamentos em blocos casualizados (DBC) e inteiramente casualizados (DIC) quanto aos caracteres altura e produção de massa verde em erva-mate (Ilex paraguariensis A. St. - Hil.). O experimento, conduzido na Fazenda Experimental do Canguiri, da Universidade Federal do Paraná, em Pinhais, PR, foi composto de cinco procedências, quatro com 13 e uma com 12 progênies de meias-irmãs. Cada progênie continha 54 plantas (nove parcelas de seis plantas). O experimento seguiu o modelo látice 8 x 8 com nove repetições balanceadas. As análises foram conduzidas usando-se tanto este modelo quanto os modelos DBC e DIC. Com relação ao caráter altura, a estimativa da eficiência do DBC em relação ao DIC (Êb/i) foi de 48,6%; do látice em relação ao DBC (Êl/b), de 61%; e do látice em relação ao DIC (Êl/i), de 139%. A estimativa da correlação intraclasse entre plantas dentro das parcelas ( cˆ 2 ) foi de 9,4% para o DBC e zero para o látice. Para o caráter produção de massa verde, Êb/i, Êl/b e Êl/i foram de 14,3; 81,7; e 108%, respectivamente; e cˆ 2 , 16,9% para o DBC e 3,1% para o látice. Essas estimativas, associadas a uma estimativa de F de Snedecor altamente significativa dos dois caracteres, permitiram concluir que a capacidade de teste do DBC foi satisfatória para o caráter altura de plantas, mas insatisfatória para o caráter produção de massa verde
The Role of Meningioma-1 (Mn1) Gene as Marker for Prognosis and Minimal Residual Disease Monitoring in Acute Myeloid Leukemia: A Concise Review
Molecular markers are necessary for prognostic stratification and monitoring of Minimal
Residual Disease (MRD) in Acute Myeloid Leukemia (AML) [1,2]. Cytogenetic aberrations have
long been recognized as the most important prognostic variable in AML, and are still the major
determinant for post-remission therapy [3]. Unfortunately, only 50-60% of AML patients present
an abnormal karyotype at diagnosis, while the remaining cases display a Normal Karyotype (NK).
NK AML patients are generally included in an “intermediate risk” prognostic group, that is however
characterized by a heterogeneous clinical course. To stratify prognosis of NK AML patients,
numerous studies have led, in the last decade, to the introduction of different molecular markers
such as FLT3, NPM1, BAALC and CEBPA [4-7]. Still, their use to monitor disease, either defining
remission status and detecting relapse as early as possible, is still somehow controversial, due to
fluctuations during disease course, low incidence rates in AML and sensitivity of the technologies
detecting the single marker [8-10]. These limitations have, to date, precluded a timely and precise
quantification of disease in NK AML patients, thus preventing from a complete individualization
of post-remission therapy and early treatment in case of impending relapse. In other words, in
NK AML it has not been reached the precision achieved in BCR/ABL-positive chronic myeloid
leukemia and PML/RAR alpha mutated acute promyelocytic leukemia
Estimulación del sistema auditivo con evaluación del nervio vestibular en el medio acuático a través de juegos sensoriales recreativos
El presente trabajo de investigación trata el estudio sobre la estimulación del sistema auditivo con evaluación del nervio vestibular a través de juegos sensoriales recreativos en el agua. Dicho trabajo está orientado a una práctica fundamentada del tema, teniendo como referente el medio acuático, ambiente en el cual gran cantidad de personas de distintas edades, transitan permanentemente para mejorar su calidad de vida
Long-term disease-free survival in surgically-resected oral tongue cancer: a 10-year retrospective study
Sopravvivenza libera da malattia a lungo termine nel tumore della lingua mobile operato: studio retrospettivo a 10 anni.PLAIN-LANGUAGE-SUMMARY:
Early and loco-regionally advanced oral tongue squamous cell carcinoma (OTSCC) can be treated by surgery alone or followed by adjuvant radiotherapy or chemoradiotherapy. Nevertheless, up to 40% of patients develop tumour relapse. The aim of our study is to investigate the clinical and pathological features associated with reduced disease-free survival (DFS) in a cohort of surgically-resected OTSCC patients. One hundred and six patients surgically resected for OTSCC were retrospectively identified from clinical records. DFS was calculated according to the Kaplan\u2013Meier method and differences between variables were assessed with Log-Rank test. A multivariable Cox regression model was used to analyse the impact of different prognostic factors on DFS. After a median of follow-up of 8.9 years, 22 events, including 11 deaths, were observed. Overall, the 5-year DFS-rate was 87.4%. The presence of extra-nodal extension (p = 0.023) and perineural invasion (p = 0.003) were significantly correlated with shorter DFS (in univariate analysis). In multivariable analysis, extra-nodal extension and perineural invasion confirmed their role as independent prognostic factors associated with an increased risk of disease recurrence [hazard ratio (HR) 2.87, 95% CI 1.11-7.42, p = 0.03; HR 3.85, 95% CI 1.49-9.96, p = 0.006, respectively]. p16 and p53 expressions in tumour cells were detected in 12% (n = 9) and 46% (n = 40) of cases, respectively. No differences in DFS were observed between p16+ and p16- (p = 0.125) and between p53+ and p53- tumours (p = 0.213). In conclusion, radical surgery, eventually followed by adjuvant radiotherapy or chemo-radiotherapy, can achieve high cure rates in OTSCC. After long-term follow-up, perineural invasion and extra-nodal extension confirmed their role as prognostic factors associated with reduced DFS in OTSCC patients
Sustained low-efficiency dialysis with regional citrate anticoagulation in critically ill patients with COVID-19 associated AKI: A pilot study
Acute Kidney Injury (AKI) is a frequent complication in critically ill patients with Coronavirus disease 2019 (COVID-19), and it has been associated with worse clinical outcomes, especially when Kidney Replacement Therapy (KRT) is required. A condition of hypercoagulability has been frequently reported in COVID-19 patients, and this very fact may complicate KRT management. Sustained Low Efficiency Dialysis (SLED) is a hybrid dialysis modality increasingly used in critically ill patients since it allows to maintain acceptable hemodynamic stability and to overcome the increased clotting risk of the extracorporeal circuit, especially when Regional Citrate Anticoagulation (RCA) protocols are applied. Notably, given the mainly diffusive mechanism of solute transport, SLED is associated with lower stress on both hemofilter and blood cells as compared to convective KRT modalities. Finally, RCA, as compared with heparin-based protocols, does not further increase the already high hemorrhagic risk of patients with AKI. Based on these premises, we performed a pilot study on the clinical management of critically ill patients with COVID-19 associated AKI who underwent SLED with a simplified RCA protocol. Low circuit clotting rates were observed, as well as adequate KRT duration was achieved in most cases, without any relevant metabolic complication nor worsening of hemodynamic status
Symbolic computation of hyperbolic tangent solutions for nonlinear differential-difference equations
A new algorithm is presented to find exact traveling wave solutions of
differential-difference equations in terms of tanh functions. For systems with
parameters, the algorithm determines the conditions on the parameters so that
the equations might admit polynomial solutions in tanh.
Examples illustrate the key steps of the algorithm. Parallels are drawn
through discussion and example to the tanh-method for partial differential
equations.
The new algorithm is implemented in Mathematica. The package
DDESpecialSolutions.m can be used to automatically compute traveling wave
solutions of nonlinear polynomial differential-difference equations. Use of the
package, implementation issues, scope, and limitations of the software are
addressed.Comment: 19 pages submitted to Computer Physics Communications. The software
can be downloaded at http://www.mines.edu/fs_home/wherema
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