Complex dynamics in simple systems with seasonal parameter oscillations

We study systems with periodically oscillating parameters that can give way to complex periodic or non periodic orbits. Performing the long time limit, we can define ergodic averages such as Lyapunov exponents, where a negative maximal Lyapunov exponent corresponds to a stable periodic orbit. By this, extremely complicated periodic orbits composed of contracting and expanding phases appear in a natural way. Employing the technique of $\epsilon$-uncertain points, we find that values of the control parameters supporting such periodic motion are densely embedded in a set of values for which the motion is chaotic. When a tiny amount of noise is coupled to the system, dynamics with positive and with negative non-trivial Lyapunov exponents are indistinguishable. We discuss two physical systems, an oscillatory flow inside a duct and a dripping faucet with variable water supply, where such a mechanism seems to be responsible for a complicated alternation of laminar and turbulent phases.Comment: New version with major change

Active whey protein edible films and coatings incorporating lactic acid bacteria for fungi control in cheese

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β-lactoglobulin micro- and nanostructures as bioactive compounds vehicle: In vitro studies

β-Lactoglobulin (β-Lg) is known to be capable to bind hydrophilic and hydrophobic bioactive compounds. This research aimed to assess the in vitro performance of β-Lg micro- (diameter ranging from 200 to 300 nm) and nano (diameter < 100 nm) structures associated to hydrophilic and hydrophobic model compounds on Caco-2 cells and under simulated gastrointestinal (GI) conditions. Riboflavin and quercetin were studied as hydrophilic and hydrophobic model compounds, respectively. Cytotoxicity experiment was conducted using in vitro cellular model based on human colon carcinoma Caco-2 cells. Moreover, the digestion process was simulated using the harmonized INFOGEST in vitro digestion model, where samples were taken at each phase of digestion process - oral, gastric and intestinal - and characterized in terms of particle size, polydispersity index (PDI), surface charge by dynamic light scattering (DLS); protein hydrolysis degree by 2,4,6-trinitrobenzene sulfonic acid (TNBSA) assay and native polyacrylamide gel electrophoresis; and bioactive compound concentration. Caco-2 cell viability was not affected up to 21 × 10−3 mg mL−1 of riboflavin and 16 × 10−3 mg mL−1 quercetin on β-Lg micro- and nanostructures. In the oral phase, β-Lg structures’ particle size, PDI and surface charge values were not changed comparing to the initial β-Lg structures (i.e., before being subjected to in vitro GI digestion). During gastric digestion, β-Lg structures were resistant to proteolytic enzymes and to acid environment of the stomach – confirmed by TNBSA and native gel electrophoresis. In vitro digestion results indicated that β-Lg micro- and nanostructures protected both hydrophilic and hydrophobic compounds from gastric conditions and deliver them to target site (i.e., intestinal phase). In addition, β-Lg structures were capable to enhance riboflavin and quercetin bioaccessibility and bioavailability potential compared to bioactive compounds in their free form. This study indicated that β-Lg micro- and nanostructures were capable to enhance hydrophilic and hydrophobic compounds bioavailability potential and they can be used as oral delivery systems.Livia de Souza Simoes gratefully acknowledges her grant to CNPq (Conselho Nacional de Desenvolvimento Cientifico e Tecnologico, Brasil) from Brazil. The authors also would like to acknowledge Luis Abrunhosa, from Centre of Biological Engineering, for assistance in High Pressure Liquid Chromatography -Fluorescence detection. This study was supported by FCT under the scope of the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI-01-0145-FEDER-006684) and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte. This study was also supported by FCT under the scope of the Project RECI/BBB-EBI/0179/2012 (FCOMP-01-0124-FEDER-027462).info:eu-repo/semantics/publishedVersio

Cellulose from sugarcane bagasse as a potential prebiotic agent

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Design of green routes for cellulose extraction from a sugarcane by-product

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Antioxidant activity of chitooligosaccharides upon two biological systems: erythrocytes and bacteriophages

Most of the reports to date on the antioxidant capacity of chitosans and chitooligosaccharides (COS) are based on strictly chemical methods. When studying antioxidants with potential in vivo applications, the method used to evaluate the antioxidant activity should be representative of the conditions in which the antioxidant might have a protective effect. In this work we evaluate the antioxidant activity of two COS mixtures and a low MW chitosan (LMWC) upon two biological oxidizable substrates – erythrocytes and phages, subjected to accelerated oxidation conditions. Our results suggest that COS/LMWC can be used as antioxidants in biological systems. All the tested compounds reduced either the hemolytic and DNA damage, by inhibiting H2O2- and AAPH-radicals. However, the results obtained for these biological assays did not reveal a dose dependence, contrary to the chemical assay, suggesting that the protective concentrations should be established, in order to prevent enhancement of the oxidative damage – i.e. a prooxidant effect.info:eu-repo/semantics/acceptedVersio

ESTIMULACIÓN ELÉCTRICA DE CANALES DE ALPACAS PARA MEJORAR SU CALIDAD ORGANOLÉPTICA

El objetivo del presente trabajo fue demostrar que la estimulación eléctrica tiene un efecto significativo sobre la calidad de la carne de la alpaca en los aspectos de terneza, jugosidad, sabor y olor; y que además influye en la capacidad de su conservación. Se utilizó 12 alpacas hembras adultas de 4-4.5 años de edad y 50-60 kg p.v. Las canales fueron estimuladas eléctricamente a los 60 minutos del sacrificio, usando electrodos colocados en el tejido muscular. A cada media canal tratada se le estimuló con 500 voltios por 60 (T1) ó 30 segundos (T2), y con 600 voltios por 60 (T3) ó 30 segundos (T4); dejando sin estimulación eléctrica a las medias canales control. El tratamiento tuvo un efecto significativo (p=0.00) sobre el pH de la carne tratada, produciendo un menor crecimiento microbiano a las 24 horas post estimulación (p=0.004), especialmente en el tratamiento T2. En las características organolépticas se obtuvo un efecto significativo para el olor con el tratamiento T1 (p=0.009), sabor con el tratamiento T4 (p=0.002), terneza con los tratamientos T2 (p=0.023) y T3 (p=0.004), y jugosidad con el tratamiento T4 (p=0.005).Electrical stimulation is a technique that may reduce the lenght of maturity, rigor mortis and acidity of meat, as well as improving sensory characteristics. The objetive of the study was to show that the electrical stimulation has a significant effect on the quality of alpaca meat such as tenderness, juiceness, flavor, odor and sanitary condition. Twelve female alpacas from 4 to 5 year old and 50-60 kg of body weight were used. They were slaughtered and electrically stimulated 60 minutes later using electrodes on muscular tissue. All half carcasses were stimulated with 500 v per 60 s (T1), 500 v per 30 s (T2), 600 v per 60 s (T3), and 600 v per 30 s (T4). All other half carcasses were kept without electrically stimulation. The results indicated that the electrical stimulation had a significant effect (p=0.00) on the pH alpaca meat reducing microbial growth 24 h after stimulation (p=0.004), where treatment T2 (500 v/60s) showed the best effect. The evaluation of sensory characteristics showed a significant effect for odor on treatment T1 (p=0.009), flavor on treatment T4 (p=0.002), tenderness on treatments T2 (p=0.023) and T3 (p=0.004), and juiceness on treatment T4 (p=0.005)

In situ degradability of dry matter and crude protein of pisonay (Erythrina falcata) leaves and petiole

El estudio tuvo como objetivo determinar la composición química y la degradabilidad ruminal de la materia seca (MS) y proteína cruda (PC) del pisonay (Erythrina falcata) a los 105, 120 y 135 días de rebrote. Se tomaron muestras de hojas y peciolo, se secaron y se colocaron 8 g de muestra molida por bolsa de nylon en el rumen de tres chivatos machos adultos por 0, 24, 48 y 72 horas. Los valores de MS y PC fueron 24.4 y 21.4% a los 105, 24.8 y 23.2% a los 120 y, 27.2 y 24.4% a los 135 días, respectivamente. La degradabilidad ruminal de la fracción insoluble potencialmente degradable de MS y PC fue 29.6 y 42.9% a los 105, 24.3 y 31.4% a los 120 y, 14.9 y 24.1% a los 135 días, respectivamente, y la degradabilidad efectiva de MS y PC fue 41.3 y 41.2% a los 105, 36.5 y 30.3% a los 120 y, 32.3 y 30.5% a los 135 días, respectivamente. El estudio demuestra que el follaje E. falcata a los 105 días de crecimiento posee una mayor ventaja proteica para los caprinos.The study aimed to determine the chemical composition and ruminal degradability of dry matter (DM) and crude protein (CP) of Erythrina falcata at 105, 120 and 135 days of regrowth. Leaves and petiole samples were dried and 8 g of dry grounded samples were placed in nylon bags in the rumen of three male goats during 0, 24, 48 and 72 hours. The DM and CP values were 24.4 and 21.4% at 105, 24.8 and 23.2% at 120 and, 27.2 and 24.4% at 105 days respectively. The ruminal degradability of potentially degradable insoluble fraction of DM and CP was 29.6 and 42.9% at 105, 24.3 and 31.4% at 120 and, 14.9 and 24.1% at 135 days, respectively, and the effective degradability of DM and CP was 41.3 and 41.2% at 105, 36.5 and 30.3% at 120 and, 32.3 and 30.5% at 135 days respectively. The study showed a higher protein advantage in goats at 105 days of growth of E. falcata foliage

Heterogeneous Nuclear Ribonucleoprotein K Is Overexpressed in Acute Myeloid Leukemia and Causes Myeloproliferation in Mice via Altered

Acute myeloid leukemia (AML) is driven by numerous molecular events that contribute to disease progression. Herein, we identify hnRNP K overexpression as a recurrent abnormality in AML that negatively correlates with patient survival. Overexpression of hnRNP K in murine fetal liver cells results in altered self-renewal and differentiation potential. Further, murine transplantation models reveal that hnRNP K overexpression results in myeloproliferation in vivo. Mechanistic studies expose a direct functional relationship between hnRNP K and RUNX1—a master transcriptional regulator of hematopoiesis often dysregulated in leukemia. Molecular analyses show that overexpression of hnRNP K results in an enrichment of an alternatively spliced isoform of RUNX1 lacking exon 4. Our work establishes hnRNP K’s oncogenic potential in influencing myelogenesis through its regulation of RUNX1 splicing and subsequent transcriptional activity

Ultrastructure of the organ of Corti in harbor seals (Phoca vitulina)

Ultrastructural descriptions of the inner ear of highly sound-dependent mammalian species are lacking and needed to gain a better understanding of the hearing sense. Here, we present the first morphometric descriptions of the sensory cells of the inner ear in the harbor seal (Phoca vitulina), a mammal with broadly sensitive amphibious hearing. Scanning electron micrographs of the apical surface of the outer hair cells (OHCs) and inner hair cells (IHCs) within the organ of Corti were obtained from five individuals and analyzed by linear and geometric morphometrics. Measurements were taken at regular locations along the cochlea. The spiral shape of the seal cochlea contained two and a half turns. The organ of Corti had an average length of 27.7 mm with 12,628 OHCs (12,400-12,900). Six linear morphometric parameters showed significant patterns of change associated with their location within the cochlear spiral. Likewise, these trends were similarly expressed in cell configuration (cell blocks with 57 landmarks in 12 representative cells) revealed by geometric morphometry. Cell configuration varied predictably with position in the cochlea according to clustering analyses and Procrustes ANOVA (F= 25.936, p&lt;0001). Changes associated with OHCs were primarily responsible for observed changes in cell configuration. An integration trend in cell shape change was also observed in which IHCs and OHCs share features in their morphological variation by the two-block partial least squares analysis (CR=0.987, p&lt;0.001) and the modularity hypothesis (CV=0.99, p=0.05). These descriptive and quantitative findings provide a baseline for the morphology and morphometry of the sensory cells of the organ of Corti in harbor seals, allowing for comparisons between normal and pathological features. This initial morphological description should enable the correlation between position, morphometric features, and frequency coding along the spiral of the inner ear in this species, whose hearing ability is well studied