Improving the thermal stability of different types of xylan by acetylation

The impact of various degrees of acetylation on improving the thermal stability of xylan isolated from different botanical source has been studied; methylglucuronoxylan from birch and eucalyptus, arabinoglucuronoxylan from spruce and glucuronoarabinoxylan from sugarcane bagasse and straw. The lower molecular weight of nonacetylated methylglucuronoxylan (17.7-23.7 kDa) and arabinoglucuronoxylan (16.8 kDa) meant that they were more soluble in water than glucuronoarabinoxylan (43.0-47.0 kDa). The temperature at the onset of degradation increased by 17-61 degrees C and by 75-145 degrees C for low and high acetylated xylans respectively, as a result of acetylation. A glass transition temperature in the range of 121-132 degrees C was observed for the samples non-acetylated and acetylated at low degree of acetylation (0.0-0.6). The acetylation to higher degrees (1.4-1.8) increased the glass transition temperature of the samples to 189-206 degrees C. Acetylation proved to be an efficient method for functionalization of the xylan to increase the thermal stability.Peer reviewe

An ‛Aukward' Tale: A Genetic Approach to Discover the Whereabouts of the Last Great Auks.

One hundred and seventy-three years ago, the last two Great Auks, Pinguinusimpennis, ever reliably seen were killed. Their internal organs can be found in the collections of the Natural History Museum of Denmark, but the location of their skins has remained a mystery. In 1999, Great Auk expert Errol Fuller proposed a list of five potential candidate skins in museums around the world. Here we take a palaeogenomic approach to test which-if any-of Fuller's candidate skins likely belong to either of the two birds. Using mitochondrial genomes from the five candidate birds (housed in museums in Bremen, Brussels, Kiel, Los Angeles, and Oldenburg) and the organs of the last two known individuals, we partially solve the mystery that has been on Great Auk scholars' minds for generations and make new suggestions as to the whereabouts of the still-missing skin from these two birds

The Developmental Competence of Oocytes Retrieved from The Leading Follicle in Controlled Ovarian Stimulated Cycles

Abstract Background: This study compares the developmental capacity of gametes retrieved from the largest follicle with small follicles of a cohort in controlled ovarian stimulated cycles

Estudos sobre a nutrição mineral do arroz: XVI, absorção radicular e foliar do rádio fósforo por diversas variedades

Excised roots obtained from 8 varieties of rice (IAC-164, 165 and 1246, Batatais, Caqui, Dourado Precoce, 90 Dias and Senbon) were used to study the kinetics of P uptake. Three cultivars (IAC-164, 90 Dias and Senbon) were employed in an experiment designed to compare root and leaf uptake and to evaluate the long distance transport. The main conclusions were as follows: a) after 180 minutes of contact with the external solution the uptake reached a maximum in the case of varieties IAC-164 and 165 , 90 Dias and Dourado Precoce; the same took place with the remaining cultivars after 240 minutes; b) the best fitting for individual varieties was obtained by using eiter potential or exponential models of adjustment wherein time was the independent variable and rate of uptake was the dependent one. c) IAC-164 and IAC-165 showed the highest efficiency of absorption while Dourado Precoce and 90 dias showed the lowest one. d) some evidence for the operation of a dual uptake mechanism was obtained when data from all varieties were put together; e) root absorption was usually higher than foliar uptake.Estudando-se a absorção do rádio fósforo por raízes destacadas das variedades IAC-164, 165 e 1246, Batatais, Caqui, Dourado precoce, 90 dias e Senbon (as primeiras nacionais, a última japonesa) verificou-se diferença entre as mesmas na cinética de absorção. Nas condições experimentais, obteve-se evidência de um padrão duplo de absorção do anion fosfato. A absorção radicular mostrou-se mais eficiente que a foliar em termos de quantidade absorvida e de transporte a longa distânci

Atividade reprodutiva e estrutura populacional de Myotis nigricans (Schinz, 1821) (Chiroptera: Vespertilionidae) no sul do Brasil

Among mammals, bats present the greatest diversity in reproductive strategies. In this study we analyzed reproductive and population characteristics of Myotis nigricans over one year in a temperate region in Brazil. We carried out the samplings in an anthropic roost, in Pedras Grandes municipality, Santa Catarina state. We captured bats monthly with mist nets installed at the roosts exits and identified the captured individuals according to sex, reproductive condition and age. There was greatest number of females than males. Population size was estimated from 569 to 1050 individuals. Births occurred mainly from September to January, with more than one pregnancy event along the year, evidencing a seasonal and bimodal polyester pattern. The reproductive period of M. nigricans in southern Brazil is similar to the records made in other regions. Despite of it, there is no pattern along its distribution range. © SAREM, 2018

State transfer in dissipative and dephasing environments

By diagonalization of a generalized superoperator for solving the master equation, we investigated effects of dissipative and dephasing environments on quantum state transfer, as well as entanglement distribution and creation in spin networks. Our results revealed that under the condition of the same decoherence rate $\gamma$, the detrimental effects of the dissipative environment are more severe than that of the dephasing environment. Beside this, the critical time $t_c$ at which the transfer fidelity and the concurrence attain their maxima arrives at the asymptotic value $t_0=\pi/2\lambda$ quickly as the spin chain length $N$ increases. The transfer fidelity of an excitation at time $t_0$ is independent of $N$ when the system subjects to dissipative environment, while it decreases as $N$ increases when the system subjects to dephasing environment. The average fidelity displays three different patterns corresponding to $N=4r+1$, $N=4r-1$ and $N=2r$. For each pattern, the average fidelity at time $t_0$ is independent of $r$ when the system subjects to dissipative environment, and decreases as $r$ increases when the system subjects to dephasing environment. The maximum concurrence also decreases as $N$ increases, and when $N\rightarrow\infty$, it arrives at an asymptotic value determined by the decoherence rate $\gamma$ and the structure of the spin network.Comment: 12 pages, 6 figure

Quaternion-Loop Quantum Gravity

It is shown that the Riemannian curvature of the 3-dimensional hypersurfaces in space-time, described by the Wilson loop integral, can be represented by a quaternion quantum operator induced by the SU(2) gauge potential, thus providing a justification for quaternion quantum gravity at the Tev energy scale.Comment: 5 pages, latex, no figures. Improved pdf. To appear in the Foundations of Physic

Apathy and functional disability in behavioral variant frontotemporal dementia

Background Behavioral variant frontotemporal dementia (bvFTD) has profound consequences on patients and their families. In this multicenter study, we investigated the contribution of cognitive and neuropsychiatric factors to everyday function at different levels of overall functional impairment. Methods In a retrospective cross-sectional study, 109 patients with bvFTD from 4 specialist frontotemporal dementia centers (Australia, England, India, and Brazil) were included. The measures administered evaluated everyday function (Disability Assessment for Dementia [DAD]), dementia staging (Clinical Dementia Rating [CDR]), general cognition (Addenbrooke’s Cognitive Examination–revised [ACE-R]), and neuropsychiatric symptoms (Neuropsychiatric Inventory [NPI]). Patients were then subdivided according to functional impairment on the DAD into mild, moderate, severe, and very severe subgroups. Three separate multiple linear regression analyses were run, where (1) total DAD, (2) basic activities of daily living (BADL), and (3) instrumental activities of daily living (IADL) scores were dependent variables; ACE-R total score and selected NPI domains (agitation/aggression, euphoria, apathy, disinhibition, irritability, aberrant motor behavior) were used as independent variables. Age, sex, education, and country of origin were controlled for in the analyses. Results Cognitive deficits were similar across the mild, moderate, and severe subgroups but significantly worse in the very severe subgroup. NPI domain scores (agitation/aggression, euphoria, apathy, disinhibition, irritability, aberrant motor behavior) did not differ across the DAD subgroups. In the multiple regression analyses, a model including ACE-R and NPI apathy explained 32.5% of the variance for total DAD scores. For IADL, 35.6% of the variance was explained by the ACE-R only. No model emerged for BADL scores. Conclusions Cognitive deficits and apathy are key contributors to functional disability in bvFTD but factors underlying impairment in BADLs remain unclear. Treatments targeting reduction of disability need to address apathy and cognitive impairment to ensure greater efficacy, especially in regards to IADLs

Microtiming patterns and interactions with musical properties in Samba music

In this study, we focus on the interaction between microtiming patterns and several musical properties: intensity, meter and spectral characteristics. The data-set of 106 musical audio excerpts is processed by means of an auditory model and then divided into several spectral regions and metric levels. The resulting segments are described in terms of their musical properties, over which patterns of peak positions and their intensities are sought. A clustering algorithm is used to systematize the process of pattern detection. The results confirm previously reported anticipations of the third and fourth semiquavers in a beat. We also argue that these patterns of microtiming deviations interact with different profiles of intensities that change according to the metrical structure and spectral characteristics. In particular, we suggest two new findings: (i) a small delay of microtiming positions at the lower end of the spectrum on the first semiquaver of each beat and (ii) systematic forms of accelerando and ritardando at a microtiming level covering two-beat and four-beat phrases. The results demonstrate the importance of multidimensional interactions with timing aspects of music. However, more research is needed in order to find proper representations for rhythm and microtiming aspects in such contexts

Enhancing meat quality of weaned piglets with the dietary incorporation of Ulva lactuca and carbohydrases supplementation

Pubmed Free articleThe impact of the dietary incorporation of 7% Ulva lactuca, a green seaweed, on the quality and nutritional value of piglet’s meat was assessed. U. lactuca is rich in nutrients and bioactive compounds but its cell wall is composed of complex polysaccharides that reduce their bioavailability. Therefore, the effect of supplementing piglet diets with exogenous carbohydrases was also assessed here. A total of 40 male weaned piglets were divided into four dietary groups, each with 10 piglets: control (wheat, maize and soybean meal-based diet), UL (7% U. lactuca replacing the control diet), UL +R (UL and 0.005% Rovabio®), and UL +E (UL and 0.01% ulvan lyase). The piglets were fed the diets for 2 weeks. The results showed that incorporating U. lactuca in piglet diets did not influence most of the meat quality traits (P >0.05). However, the incorporation of U. lactuca with the commercial carbohydrase (UL +R) increased the amount of the docosahexaenoic acid (DHA; 22:6n-3) in their meat (P =0.011) compared with the control, by 54%. In addition, meat from piglets fed seaweed diets showed a nearly two-fold increase in iodine contents (P <0.001). Meat tenderness, juiciness and overall acceptability of piglets fed the control diet and the UL diet were lower than those fed the diets containing seaweed and carbohydrases (P <0.001). Overall, the findings indicate that 7% U. lactuca in the diets of weaned piglets had no major detrimental effects on meat quality and their carbohydrase supplementation has the potential to improve meat sensory traits.Funding: This research was funded by Fundação para a Ciência e a Tecnologia (FCT), Portugal, through PTDC/CAL-ZOO/30238/2017 grant, associated with a post-doc contract to M.C., and PhD fellowships to J.M. P. (SFRH/BPD/116816/2016) and D.M.R. (SFRH/BD/143992/2019). CIISA (UIDB/00276/2020), AL4AnimalS (LA/P/0059/2020) and LEAF (UIDB/04129/2020) grants, also from FCT, are also acknowledged. The authors acknowledge Teresa Costa from Indukern, Lda. (Sintra, Portugal), for the Rovabio® Excel AP kind donation. The graphical abstract was created using BioRender.com (https://biorender.com/).info:eu-repo/semantics/publishedVersio