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The rocky shores of the north-east Atlantic have been long studied. Our focus is from Gibraltar to Norway plus the Azores and Iceland. Phylogeographic processes shape biogeographic patterns of biodiversity. Long-term and broadscale studies have shown the responses of biota to past climate fluctuations and more recent anthropogenic climate change. Inter- and intra-specific species interactions along sharp local environmental gradients shape distributions and community structure and hence ecosystem functioning. Shifts in domination by fucoids in shelter to barnacles/mussels in exposure are mediated by grazing by patellid limpets. Further south fucoids become increasingly rare, with species disappearing or restricted to estuarine refuges, caused by greater desiccation and grazing pressure. Mesoscale processes influence bottom-up nutrient forcing and larval supply, hence affecting species abundance and distribution, and can be proximate factors setting range edges (e.g., the English Channel, the Iberian Peninsula). Impacts of invasive non-native species are reviewed. Knowledge gaps such as the work on rockpools and host–parasite dynamics are also outlined.
Protein is the most costly nutrient in fish feed, and while diets offered in the early stages of development typically have high levels of CP, they do not always correspond to the real requirements of the animals. Thus, research that seeks to learn the true nutritional requirements of fish is fundamental to improving commercial fish culture. The present study evaluated the protein requirements of Nile tilapia (Oreochromis niloticus) under larviculture. Fish performance, gene expression for digestive enzymes and their enzymatic activity and stress response to air exposure were analyzed. Four experimental diets differing in CP level were formulated: 30%, 36%, 42% and 48%. Fish larvae were fed the experimental diets during development and sampled 10, 20 and 30 days after the beginning of the experiment for performance, gene expression and enzymatic activity. At sampling time 30, stress resistance was also evaluated by means of an air exposure test. At sampling time 10, CP levels between 36% and 48% could be used for a better performance. During this period, pepsinogen expression was greater for 30% CP, intermediate for 42% and lower for 36% and 48%. After this initial period, diets of between 30% and 42% CP are recommended for better performance. At sampling time 20, gene expression for digestive enzymes and their enzymatic activity were similar for all diets tested. At sampling time 30, the diet of 42% CP induced both greater pepsinogen expression and pepsin activity. Survival after the air exposure test after 30 days of feeding was influenced by CP level in the diet, with the highest survival being for fish fed with 36% CP. Taken together, the present results demonstrate that dietary CP influences digestive enzyme gene expression and activity, and suggest that the best CP levels for Nile tilapia larviculture vary depending on larval stage.
Direct polycondensation of L-lactic acid with a comonomer allows tailoring the properties of the product from the very first step. The viscous L-lactic acid co-oligomers with star-shaped architectures obtained were modified with three different acrylate monomers. Regardless the functionalization agent, UV curing was fast and all materials were cell compatible and promoted cell adhesion. The physical properties of the three star-shaped films exhibited a consistent trend as swelling capacity, hydrolytic instability, and gel content decreased simultaneously. A higher network density increased crosslinking degree and gel content among the films with an isocyanate group. The methacrylic end group functionalized material, lowest molecular weight, consistently exhibited the higher hydrolytic instability. Comparison of physical properties of these films with the corresponding linear materials reported previously confirmed the influence of precursor molecular architecture on the final material. The methodology developed herein is prone to scale-up and lead to the industrial production of new bioadhesives.
The thermomechanical processing of NiTi shape memory alloys usually involves several steps of hot and/or cold deformation. The present work presents the structural characterization of a Ni-rich NiTi alloy bar, produced by vacuum-induced melting and thermomechanical processing in laboratory scale, aiming at massive production in the future. This study focused on the first step of hot working at 800 °C during rotary forging. Microstructural characterization was performed using differential scanning calorimetry, high- and low-temperature X-ray diffraction (XRD) using a laboratory source and synchrotron XRD. Thus, it was possible to obtain the phase transformation characteristics of the material: the transformation temperatures and the transformation sequence. Proposed thermomechanical processing is intended for production of bars and wires that will be subsequently drawn to get thin wires, for different applications, including orthodontic arch wires.
There is an increasing interest in improving neurocysticercosis (NCC) diagnosis through the search of new and alternative antigenic sources, as those obtained from heterologous antigens. The aim of this study was to obtain potential biomarkers for NCC diagnosis after gel filtration chromatography [gel filtration fraction (GFF)] from the total saline extract (SE) from Taenia saginata metacestodes, followed by protein identification and application in immunodiagnostic. SE and GFF proteic profiles were characterized in gel electrophoresis, and diagnostic performance was verified by testing 160 serum samples through enzyme-linked immunosorbent assay and immunoblotting. Sensitivity (Se), specificity (Sp) and other diagnostic parameters were calculated. Polypeptides of interest in the diagnosis of human NCC present at GFF were analysed by mass spectrometry (MS) and B-cell epitopes were predicted. GFF had the best diagnostic parameters: Se 93·3%; Sp 93%; AUC 0·990; LR+ = 13·42 and LR− = 0·07, and proved to be useful reacting with serum samples in immunoblotting. Proteic profile ranged from 64 to 68 kDa and enolase and calcium binding protein calreticulin precursor were identified after MS. The enolase and calcium-binding protein calreticulin precursor showed 18 and 10 predicted B-cell epitopes, respectively. In conclusion we identified important markers in the GFF with high efficiency to diagnose NCC.
Increasingly, archaeological research in Amazonia is revealing complex precolonial occupation in areas around riverine confluences. In 2014, the first site-based archaeological investigations were undertaken in Gurupá, Pará, Brazil, a municipality that spans the region of the Xingu-Amazon confluence. The Portuguese controlled access to Amazonia from 1623 onward through a network of settlements organized around Gurupá. Results from extensive excavations of terra preta sites, landscape archaeology, and analysis of ceramic evidence suggest that this was also a precolonial crossroads. Carrazedo, once a booming historical town (Arapijó), sits atop a significantly larger terra preta site. Excavations in historical and precolonial sectors of Carrazedo found well-preserved remains, including a precolonial house terrace complex. The extent of terra preta and earthworks at Carrazedo indicate that the precolonial occupation was more intensive than the colonial-historical period occupation. Regional survey revealed colonial-historical period sites consistently overlying expansive precolonial sites, the density and extent of which suggest a major precolonial center at the Xingu-Amazon confluence. Overall, ecological and landscape modifications appear to have been more intense in the precolonial past than during later periods. Short- and long-distance settlement networks also differed during the two periods. This as-of-yet understudied region promises to shed new light on deep-time human-environment interactions and spatial organization in the humid tropics of Amazonia.
Modifying the extent of fatty acid (FA) biohydrogenation (BH) in the rumen through diet formulation is an effective strategy for changing the content of unsaturated FAs (USFAs) in meat. The present study investigated the effects of different sources of forage in high-concentrate diets on intake, digestibility, rumen fermentation, ruminal BH, duodenal flow of FAs and rumen microbiota in Nellore steers. Intake of neutral detergent fibre (NDF) was higher in animals fed with maize silage (MS) than in those fed with sugar cane (SC) and sugar cane bagasse (SB). Higher digestibility of dry matter and NDF was found in animals fed with MS than in those fed with the other diets. In addition, higher crude protein digestibility was observed in animals fed with sugar cane bagasse than in those fed with SC. Non-fibre carbohydrate (NFC) digestibility was higher in animals fed with sugar cane than in those fed with the other diets. Intake of total and individual FAs such as C18 : 1 cis-9, C18 : 2, and C18 : 3 was similar between animals fed with MS and SB, but decreased in animals fed with SC. Diets containing MS and SB showed higher total digestibility of saturated FAs (SFAs) and USFAs, respectively and total FAs and ruminal BH of C18 : 1 and USFA. Intestinal digestibility of overall FAs did not differ among treatments, except for C18 : 3, which increased in animals fed with SC and SB. The profile of FAs in duodenal digesta and faecal outputs did not differ among treatments. However, the flow of NDF was higher in animals fed with SC than in those fed with MS and SB. Animals fed with SB showed higher values of pH than those fed with MS and SC. Animals fed with SC showed lower values of ammonia-nitrogen. Protozoan counts were only influenced by diet for species that belonged to the genera Dasytricha and Isotricha. Populations of fibrolytic bacteria (Ruminococus flavefaciens, Ruminococus albus and Fibrobacter succinogenes) were similar among diets. Populations of Selenomonas ruminantium increased 2·5 and 5 times in animals fed with MS when compared with those fed with SC and SB, respectively. The use of MS increased intake and digestibility of NDF, and the use of SC decreased ruminal BH of total USFA without changing the flow of FAs to the duodenum. Thus, different sources of forage in high-concentrate diets do not modify the duodenal flow of USFA or fibrolytic bacteria. This must be taken into account when formulating diets to modulate ruminal upsets without altering intake.
Obesity and osteoporosis may have their origins in early postnatal life. This study was designed to evaluate whether flaxseed flour use during lactation period bears effect on body adiposity and skeletal structure of male rat pups at weaning. At birth, male Wistar rats were randomly assigned to control and experimental (FF) groups, whose dams were treated with control or flaxseed flour diet, respectively, during lactation. At 21 days of age, pups were weaned to assess body mass, length and composition by dual-energy X-ray absorptiometry. The animals were then sacrificed to carry out analysis of serum profile, intra-abdominal adipocyte morphology and femur characteristics. Differences were considered significant when P<0.05. The FF group displayed the following characteristics (P<0.05): higher body mass, length, bone mineral content, bone area and concentrations of osteoprotegerin, osteocalcin and high-density lipoprotein cholesterol; higher levels of stearic, α-linolenic, eicosapentaenoic and docosapentaenoic acids and lower levels of arachidonic acid and cholesterol; smaller adipocyte area; and higher mass, epiphysis distance, diaphysis width, maximal load, break load, resilience and stiffness of femur. Flaxseed flour intake during lactation period promoted adipocyte hypertrophy down-regulation and contributed to pup bone quality at weaning.
Firstly, a brief overview will be given on different models that are able to describe the behaviour of wave propagation as a function of specific frequency ranges. Each range corresponds to different heating systems, namely, 20–100 MHz for the ion cyclotron resonant heating, 2–20 GHz for lower-hybrid heating or current drive, and 100–250 GHz for electron cyclotron resonant heating or current drive systems. The specification of every system will be explained in detail, including the typical set of equations and the assumptions needed to describe the properties of these heating or current drive systems, as well as their specific domains of validity. In these descriptions, special attention will be paid to the boundary conditions. A review of specific physical problems associated with the wave heating systems will also be provided. The review will detail the role of simulation in answering questions that arise from experiments on magnetized plasma devices devoted to fusion. A few examples that will be covered are the impact of edge turbulence on wave propagation and its consequences on heating system performance, the effects of fast particles and ponderomotive effects, among others. A study that is more focused on radio-frequency sheath effects will also be discussed. It shows that such simulations require very sophisticated tools to gain a partial understanding of the observations undertaken in dedicated experiments. To conclude this review, an overview will be given about the requirements and progress necessary to obtain relevant predictive simulation tools able to describe the wave heating systems used in fusion devices.
The use of diets with increasing proportions of concentrate to fibre can ensure appropriate energy levels and result in greater efficiency in Nellore feedlot steers. It was hypothesized that higher proportions of concentrate in the diet of these Nellore steers may affect ruminal fermentation and microbiota as a consequence of ruminal pH reduction. The present study was conducted to evaluate the effect of diets with four different roughage (hay Tifton 85) : concentrate ratios on intake, digestibility, rumen fermentation and rumen microbiota of Nellore feedlot steers. Higher proportions of concentrate in the diet did not affect intake and digestibility of dry and organic matter. The concentration of N-NH3, total rumen volatile fatty acid, acetic (C2), butyric (C4), isobutyric, valeric and isovaleric acids, and microbial nitrogen did not differ among diets. However, increasing proportions of concentrate in the diet resulted in a linear reduction in average rumen pH and increased propionic acid (C3) concentration, resulting in lower relative C2 : C3. Bacterial population of Fibrobacter succinogenes, Ruminococus flavefaciens and Ruminococcus albus decreased in the rumen. However, bacteria that are consumers of lactic acid (Selenomonas ruminantium and Megasphaera elsdenii) and producers of lactic acid (Lactobacillus sp. and Streptococcus bovis) increased when animals were fed with high-concentrate diets. The total number of protozoa was similar for the different roughage : concentrate ratios. Protozoan counts were only influenced by diet for the genus Dasytricha. The findings point to diets with increasing concentrate to Tifton 85 hay ratios as inhibiting the growth of some cellulolytic bacteria and reducing fibre digestibility, and indicate Tifton 85 hay as a possible modulated rumen fermentation in the Nellore steer feedlot.
We describe the preliminary design of a magnetograph and visible-light imager instrument to study the solar dynamo processes through observations of the solar surface magnetic field distribution. The instrument will provide measurements of the vector magnetic field and of the line-of-sight velocity in the solar photosphere. As the magnetic field anchored at the solar surface produces most of the structures and energetic events in the upper solar atmosphere and significantly influences the heliosphere, the development of this instrument plays an important role in reaching the scientific goals of The Atmospheric and Space Science Coordination (CEA) at the Brazilian National Institute for Space Research (INPE). In particular, the CEA's space weather program will benefit most from the development of this technology. We expect that this project will be the starting point to establish a strong research program on Solar Physics in Brazil. Our main aim is acquiring progressively the know-how to build state-of-the-art solar vector magnetograph and visible-light imagers for space-based platforms to contribute to the efforts of the solar-terrestrial physics community to address the main unanswered questions on how our nearby Star works.
The objective of this study was to evaluate the fatty acid profile and qualitative characteristics of meat from feedlot young bulls fed ground soybean or ground cottonseed, with or without supplementation of vitamin E. A total of 40 Red Norte young bulls, with an initial average age of 20 months, and an initial average BW of 339±15 kg, were allotted in a completely randomized design using a 2×2 factorial arrangement, with two oilseeds, and daily supplementation or not of 2500 IU of vitamin E. The experimental period was for 84 days, which was preceded by an adaptation period of 28 days. The treatments were ground soybean (SB), ground soybean plus vitamin E (SBE), ground cottonseed (CS) and ground cottonseed plus vitamin E (CSE). The percentage of cottonseed and soybean in the diets (dry matter basis) was 24% and 20%, respectively. Diets were isonitrogenous (13% CP) and presented similar amount of ether extract (6.5%). The animals were slaughtered at average live weight of 464±15 kg, and samples were taken from the longissimus dorsi muscle for the measurement of fatty acid concentration and the evaluation of lipid oxidation and color of the beef. Before fatty acid extraction, muscle tissue and subcutaneous fat of the longissimus dorsi were separated to analyze fatty acid profile in both tissues. Supplementation of vitamin E did not affect fatty acid concentration, lipid oxidation and color (P>0.05). Subcutaneous fat from animals fed CS diet had greater C12:0, C16:0 and C18:0 contents (P<0.03). In addition, CS diets reduced the C18:1 and C18:2 cis-9, trans-11 contents in subcutaneous fat (P<0.05). The muscle from animals fed CS tended to higher C16:0 and C18:0 contents (P<0.11), and decreased C18:1, C18:2 cis-9, trans-11 and C18:3 contents (P<0.05) compared with SB. The Δ9-desaturase index was greater in muscle from animals fed SB (P<0.01). At 42 days of age, meat from cattle fed SB had a greater lipid oxidation rate (P<0.05). Meat from animals fed SB diets had less lightness and redness indices than meat from animals fed CS diets after 14 days of age. In conclusion, the addition of ground cottonseed in the finishing diets did increase the saturated fatty acid content of the longissimus dorsi. However, animals fed cottonseed exhibited greater lightness and redness of beef. In this study, the addition of vitamin E did not affect qualitative characteristics of meat.
Important developments have occurred in the last two decades, since the advent of the Ovsynch protocol, on the understanding and use of synchronisation programmes for management of reproduction in dairy herds. This better understanding of oestrus cycle control associated with suboptimal reproductive performance in dairy herds has led dairy producers to quickly adopt timed artificial insemination (AI) protocols. Recent surveys have documented that fixed-time AI has become an important component of management of reproduction in high-producing herds. Furthermore, timed AI protocols have also demonstrated benefits in pasture-based milk production systems because of the ability to increase insemination rate. In general, successful use of the Ovsynch protocol requires some fundamental physiological principles to be respected, including: induction of ovulation to synchronise follicle growth in the first 2 days of the programme such that a young antral follicle is recruited; maintenance of high concentrations of progesterone during the development of the ovulatory follicle, but also effectively lyse the corpus luteum to result in very low concentration of progesterone at AI; and having a healthy pre-ovulatory follicle of moderate diameter that is highly oestrogenic and responsive to gonadotropins to synchronously ovulate 12 to 18 h after insemination. Current methods oestrous and ovulation synchronisation are still not optimal and future improvements will likely require new technologies for hormone formulation and delivery such that additional interventions are minimised to maintain acceptance by producers.
This study was conducted to investigate the physiological response of sugarcane genotypes to drought and its consequence for stalk yield. Sugarcane genotypes IACSP94-2094, IACSP96-2042 and SP87-365 were subjected to water deficit during the initial growth phase by withholding water. Resistance and sensitivity patterns were defined by the impact of drought on the stalk yield and content of soluble solids in the stalk juice. IACSP94-2094 and SP87-365 were considered drought-resistant genotypes, as the stalk dry matter production and yield of soluble solids were not reduced by the water deficit. Although drought caused reductions in leaf gas exchange in all the genotypes, IACSP96-2042 was most affected when considering the cumulative reduction in photosynthesis throughout the experimental period. This photosynthetic impairment of IACSP96-2042 was related to both non-stomatal and stomatal limitations, whereas photosynthesis in SP87-365 and IACSP94-2094 were only stomatally limited under drought. In general, a reduced photosynthetic sensitivity to water deficit was an important physiological trait for dry matter production in sugarcane plants, and the concentrations of soluble carbohydrates, sucrose, starch and proline in the leaves did not reveal consistent differences between the patterns of resistance and sensitivity. Even though IACSP96-2042 was severely affected by water shortage, this genotype presented a similar stalk yield under drought and the highest stalk yield under well-watered conditions when compared to the other genotypes. This response to variable water conditions is interesting for regions with seasonal drought, whereas the pattern of drought resistance is more appropriate for regions in which drought occurs for long periods during the crop season. Our findings are also discussed from the point of view that increases in sugarcane yield and sustainable agriculture may be reached by choosing the best genotype for each specific environmental condition.
Long-chain fatty acids are capable of inducing alterations in the homoeostasis of glucose-stimulated insulin secretion (GSIS), but the effect of medium-chain fatty acids (MCFA) is poorly elucidated. In the present study, we fed a normoenergetic MCFA diet to male rats from the age of 1 month to the age of 4 months in order to analyse the effect of MCFA on body growth, insulin sensitivity and GSIS. The 45 % MCFA substitution of whole fatty acids in the normoenergetic diet impaired whole body growth and resulted in increased body adiposity and hyperinsulinaemia, and reduced insulin-mediated glucose uptake in skeletal muscle. In addition, the isolated pancreatic islets from the MCFA-fed rats showed impaired GSIS and reduced protein kinase Bα (AKT1) protein expression and extracellular signal-related kinase isoforms 1 and 2 (ERK1/2) phosphorylation, which were accompanied by increased cellular death. Furthermore, there was a mildly increased cholinergic sensitivity to GSIS. We discuss these findings in further detail, and advocate that they might have a role in the mechanistic pathway leading to the compensatory hyperinsulinaemic status found in this animal model.
The aim of this study was to fractionate and partially characterize the antigenic extract of filariform larvae of Strongyloides venezuelensis in ion-exchange resin diethylaminoethyl sepharose (DEAE), to obtain antigenic fractions potentially applicable in immunoassays. Somatic antigen (SA) and its fractions DEAE S1 and DEAE S2 - which interacted with the resin - were evaluated by 1-dimensional electrophoresis to obtain protein profiles. SA and its fractions were tested in serum samples for IgG detection by ELISA. Serum samples (n = 155) were analysed: 50 from strongyloidiasis patients (G1), 55 from patients with other parasitic infections (G2) and 50 from healthy volunteers. Sensitivity (Se), specificity (Sp), area under curve (AUC) and likelihood ratios (LR) were calculated. The DEAE S2 fraction provided a high diagnostic value for IgG detection (Se 92·0%, Sp 91·4%, AUC 0·981, LR+ 10·75, LR − 0·09). In conclusion, the DEAE S2 fraction would probably be a source of immunodominant polypeptides for IgG detection in human strongyloidiasis serodiagnosis.
We performed group-theoretical analysis of the symmetry relationships between lattice structures of R, M1, M2, and T phases of vanadium dioxide in the frameworks of the general Ginzburg-Landau phase transition theory. The analysis leads to a conclusion that the competition between the lower-symmetry phases M1, M2, and T in the metal-insulator transition is pure symmetry driven, since all the three phases correspond to different directions of the same multi-component structural order parameter. Therefore, the lower-symmetry phases can be stabilized in respect to each other by small perturbations such as doping or stress.
Double-shelled nanotubes composed of inner shell Pb(Zr0.52Ti0.48)O3 (PZT) and outer shell TiO2 are successfully fabricated by a spin coating of each sol-gel solution on porous anodic alumina template. Field emission transmission electron microscopy images show that they have a ~ 10 nm wall thickness. The selected area electron diffraction patterns show that they have two mixed crystalline phases of tetragonal PZT and anatase TiO2. The analyses of scanning transmission electron microscopy equipped with energy dispersive X-ray spectroscopy confirm their uniform distribution of each element.