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Milk fat composition can be modulated by the inclusion of lipid supplements in ruminant diets. An interaction between the lipid supplement and the forage to concentrate ratio or the type of forage in the rations may affect milk fat composition. However, little is known about the effects of the starch-to-non-forage NDF ratio in the concentrate and lipid supplementation of goat diets. The aim of this work was to determine the role of dietary carbohydrates in goats rations supplemented with linseed oil on animal performance and milk fatty acid (FA) profile. A total of 16 dairy goats were allocated to two simultaneous experiments (two treatments each), in a crossover design with four animals per treatment and two experimental periods of 25 days. In both experiments alfalfa hay was the sole forage and the forage to concentrate ratio (33:67) remained constant. The concentrate in experiment 1 consisted of barley, maize and soybean meal (concentrate rich in starch), whereas it included soybean hulls replacing 25% of barley and 25% maize in experiment 2 (concentrate rich in NDF). As a result, the starch-to-non-forage NDF ratio was 3.1 in experiment 1 and it decreased to 0.8 in experiment 2. Both concentrates were administered either alone or in combination with 30 g/day of linseed oil. Animal performance parameters were not affected by experimental treatments. In contrast, major changes were observed in milk FA profile due to lipid supplementation and the type of concentrate. Linseed oil significantly raised vaccenic and rumenic acids as well as α-linolenic acid and its biohydrogenation intermediates while decreased medium-chain saturated FA (12:0 to 16:0) in milk fat. Milk fat contents of odd and branched-chain FA and trans-10 18:1 responded differently to linseed oil supplementation according to the concentrate fed.
In March 2011, a predator killed 33 hooded grebes, Podiceps gallardoi Rumboll (Podicipedidae), a critically endangered species, in a nesting colony at El Cervecero Lake, Santa Cruz Province, Argentina. The viscera of ten birds were examined for helminths. Two new species of Trematoda were recovered from the intestines. The plagiorchid Plagiorchis patagonensis n. sp. is mainly characterized by the larger size of the oral sucker relative to the ventral sucker, and by the distribution of the vitellarium in two lateral fields, confluent between the caecal bifurcation and the ventral sucker. The echinostomatid Euparyphium tobianum n. sp. is mainly characterized by possessing a head collar with 37–39 spines (4 angle spines on each ventral lappet, 4 lateral spines in a single row on each side, and 21–23 dorsal spines in a double row). An unidentified cestode, a tetramerid nematode and a notocotylid trematode were also recovered from the birds. This is the first record of helminths parasitizing the hooded grebe.
The astrometric capability of the Hubble Space Telescope Planetary Camera (WF/PC1) is investigated, motivated by a study of the internal velocity distribution of globular clusters. The astrometric accuracy of the HST PC will be determined ultimately by 1) the accuracy to which the aberrated images can be ‘centered’, and 2) the accuracy to which the distortions across the PC field can be modeled. A series of overlapping exposures of two clusters, NGC 6752 and M15, are utilized to examine these issues.
We have made use of maximum-likelihood image reconstruction to address the first issue, with good success. Reconstruction improves both the detectability and precision of the image centers. A preliminary exploration of the second issue, that of modeling the distortion across the PC field, is also presented, using positions derived from the multiple overlapping exposures.
δ Sct stars are among the most promising targets to perform ground-based asteroseismology. High resolution spectroscopy offers us a powerful technique to identify radial and nonradial pulsation modes, since we can easily detect oscillations and travelling features in the line profiles.
CHD may ensue from chronic systemic low-grade inflammation. Diet is a modifiable risk factor for both, and its optimisation may reduce post-operative mortality, atrial fibrillation and cognitive decline. In the present study, we investigated the usual dietary intakes of patients undergoing elective coronary artery bypass grafting (CABG), emphasising on food groups and nutrients with putative roles in the inflammatory/anti-inflammatory balance. From November 2012 to April 2013, we approached ninety-three consecutive patients (80 % men) undergoing elective CABG. Of these, fifty-five were finally included (84 % men, median age 69 years; range 46–84 years). The median BMI was 27 (range 18–36) kg/m2. The dietary intake items were fruits (median 181 g/d; range 0–433 g/d), vegetables (median 115 g/d; range 0–303 g/d), dietary fibre (median 22 g/d; range 9–45 g/d), EPA+DHA (median 0·14 g/d; range 0·01–1·06 g/d), vitamin D (median 4·9 μg/d; range 1·9–11·2 μg/d), saturated fat (median 13·1 % of energy (E%); range 9–23 E%) and linoleic acid (LA; median 6·3 E%; range 1·9–11·3 E%). The percentages of patients with dietary intakes below recommendations were 62 % (fruits; recommendation 200 g/d), 87 % (vegetables; recommendation 150–200 g/d), 73 % (dietary fibre; recommendation 30–45 g/d), 91 % (EPA+DHA; recommendation 0·45 g/d), 98 % (vitamin D; recommendation 10–20 μg/d) and 13 % (LA; recommendation 5–10 E%). The percentages of patients with dietary intakes above recommendations were 95 % (saturated fat; recommendation < 10 E%) and 7 % (LA). The dietary intakes of patients proved comparable with the average nutritional intake of the age- and sex-matched healthy Dutch population. These unbalanced pre-operative diets may put them at risk of unfavourable surgical outcomes, since they promote a pro-inflammatory state. We conclude that there is an urgent need for intervention trials aiming at rapid improvement of their diets to reduce peri-operative risks.
The organogenesis of the digestive system was described in the Amazonian pimelodid catfish species Pseudoplatystoma punctifer from hatching (3.5 mm total length, TL) to 41 days post-fertilization (dpf) (58.1 mm TL) reared at 28°C. Newly hatched larvae showed a simple digestive tract, which appeared as a straight undifferentiated and unfolded tube lined by a single layer of columnar epithelial cells (future enterocytes). During the endogenous feeding period, comprised between 20 and 96 h post-fertilization (3.5 to 6.1 mm TL), the larval digestive system experienced a fast transformation with the almost complete development and differentiation of most of digestive organs (buccopahrynx, oesophagus, intestine, liver and exocrine pancreas). Yolk reserves were not completely depleted at the onset of exogenous feeding (4 dpf, 6.1 mm TL), and a period of mixed nutrition was observed up to 6 to 7 dpf (6.8 to 7.3 mm TL) when yolk was definitively exhausted. The stomach was the organ that latest achieved its complete differentiation, characterized by the development of abundant gastric glands in the fundic stomach between 10 and 15 dpf (10.9 to 15.8 mm TL) and the formation of the pyloric sphincter at the junction of the pyloric stomach and the anterior intestine at 15 dpf (15.8 mm TL). The above-mentioned morphological and histological features observed suggested the achievement of a digestive system characteristic of P. punctifer juveniles and adults. The ontogeny of the digestive system in P. punctifer followed the same general pattern as in most Siluriform species so far, although some species-specific differences in the timing of differentiation of several digestive structures were noted, which might be related to different reproductive guilds, egg and larval size or even different larval rearing practices. According to present findings on the histological development of the digestive system in P. punctifer, some recommendations regarding the rearing practices of this species are also provided in order to improve the actual larval rearing techniques of this fast-growing Neotropical catfish species.
A prototype of an integrated closed system for fish-plankton aquaculture was developed in Iquitos (Peruvian Amazonia) in order to cultivate the Tiger Catfish, Pseudoplatystoma punctifer (Castelnau, 1855). This freshwater recirculating system consisted of two linked sewage tanks with an intensive rearing unit (a cage) for P. punctifer placed in the first, and with a fish-plankton trophic chain replacing the filters commonly used in clear water closed systems. Detritivorous and zooplanktivorous fishes (Loricariidae and Cichlidae), maintained without external feeding in the sewage volume, mineralized organic matter and permitted the stabilization of the phytoplankton biomass. Water exchange and organic waste discharge were not necessary. In this paper we describe the processes undertaken to equilibrate this ecosystem: first the elimination of an un-adapted spiny alga, Golenkinia sp., whose proliferation was favored by the presence of a small rotifer, Trichocerca sp., and second the control of this rotifer proliferation via the introduction of two cichlid species, Acaronia nassa Heckel, 1840 and Satanoperca jurupari Heckel, 1840, in the sewage part. This favored some development of the green algae Nannochloris sp. and Chlorella sp. At that time we took the opportunity to begin a 3-month rearing test of P. punctifer. The mean specific growth rate and feed conversion ratio (FCR) of P. punctifer were 1.43 and 1.27, respectively, and the global FCR, including fish in the sewage part, was 1.08. This system has proven to be suitable for growing P. punctifer juveniles out to adult, and provides several practical advantages compared with traditional recirculating clear water systems, which use a combination of mechanical and biological filters and require periodic waste removal, leading to water and organic matter losses.
The taruka Hippocamelus antisensis, a species of deer categorized as Vulnerable on the IUCN Red List, was thought to be locally extinct in the environs of La Paz, Bolivia. However, local people from Mecapaca municipality reported seeing tarukas at their former community establishment, which had been abandoned several years previously. After confirming the presence of taruka we conducted intensive surveys from which we estimated minimum abundance, and then calibrated relative abundance indices (faecal and track counts) to the abundance estimate. Using these calibrated indices we carried out a preliminary estimate of the total abundance of the species in the municipality of Mecapaca. We also carried out conservation education activities with teachers and students at local schools, which we discuss here in terms of the long-term conservation of this threatened species.
We present the first results of a comprehensive photometric O-star survey performed with a robotic twin refractor at the Universitätssternwarte Bochum located near Cerro Armazones in Chile. For three high-mass stars, Pismis 24-1, CPD − 51∘ 8946, and HD 319702, we determined the period through the Lafler-Kinman algorithm and modelled the light curves within the framework of the Roche geometry. We introduce a newly discovered eclipsing high-mass binary HD 319702 that shows well-defined eclipses favouring a detached configuration with a period of 2.0 days and an orbital inclination of 67.5∘. Combining our photometric result with the primary spectral type O8 III(f) (T1 = 34 000 K) we derive a temperature of T2 = 25 200 K for the secondary component.
In June 2011, a cluster of suspected cases of Guillain–Barré syndrome (GBS), which can follow Campylobacter jejuni infection, was identified in San Luis Río Colorado (SLRC), Sonora, Mexico and Yuma County, Arizona, USA. An outbreak investigation identified 26 patients (18 from Sonora, eight from Arizona) with onset of GBS 4 May–21 July 2011, exceeding the expected number of cases (n = 1–2). Twenty-one (81%) patients reported antecedent diarrhoea, and 61% of 18 patients tested were seropositive for C. jejuni IgM antibodies. In a case-control study matched on age group, sex, ethnicity, and neighbourhood of residence, all Arizona GBS patients travelled to SLRC during the exposure period vs. 45% of matched controls (matched odds ratio 8·1, 95% confidence interval 1·5–∞). Exposure information and an environmental assessment suggested that GBS cases resulted from a large outbreak of C. jejuni infection from inadequately disinfected tap water in SLRC. Binational collaboration was essential in investigating this cross-border GBS outbreak, the first in mainland North America since 1976.
Uni- and biaxial tension deformation tests, with different degrees of deformation, have been done on AISI 430 (EN 1.4016) ferritic stainless steel samples, which had both different chemical compositions and had undergone different annealing treatments. The initial and deformed materials were characterized by using electron backscatter diffraction and backscatter electron imaging in a scanning electron microscope together with electron probe microanalysis. The correlation observed among the chemical compositions, annealing treatment, and strain level obtained after deformation is discussed.
We are characterizing the corrosion behavior of the radioactive glass that
was made with sludge from Tank 51 at the Defense Waste Processing Facility
(DWPF) and a nonradioactive glass having the same composition, except for
the absence of radionuclides. Static dissolution tests are being conducted
in a tuff groundwater solution at glass surface area/solution volume ratios
(S/V) of 2000 and 20,000 m−1. These tests are being conducted to
assess the relationship between the behavior of this glass in a 7-day
Product Consistency Test and in long-term tests, to assess the effects of
radionuclides on the glass corrosion behavior, and to measure the
disposition of radionuclides that are released as the radioactive glass
corrodes. The radioactive glass reacts slower than the nonradioactive glass
through the longest test durations completed to date, which are 140 days for
tests at 2000 m−1 and about 400 days for tests at 20,000
m−1. This is probably because radiolysis results in lower
solution pH values being maintained in tests with the radioactive glass.
Rate-affecting alteration phases that had formed within one year in tests
with other glasses having compositions similar to the Tank 51 glass have not
yet formed in tests with either glass.
Pulses are low glycaemic foods; however, their effect on satiation is unknown. The objective was to determine the effects of an ad libitum pulse meal on food intake (FI), appetite and blood glucose (BG) before and after a test meal (4 h later) and on FI at the test meal. Males (n 24, 22·8 kg/m2) received one of four treatments or control. The pulse treatments contained pasta and tomato sauce and 44 % of energy from: (1) chickpeas, (2) lentils, (3) navy beans or (4) yellow peas. The control was pasta and tomato sauce (pasta and sauce). FI (satiation) was measured at the treatment meal (0–20 min) and at an ad libitum pizza meal 4 h later. BG and appetite were measured from 0 to 340 min. At the treatment meal, lentils led to lower FI compared to chickpeas and pasta and sauce, whereas navy beans led to lower FI compared to chickpeas. Also, lentils led to lower cumulative FI compared to pasta and sauce. All pulses led to lower BG peak and cumulative area under the curve (AUC; 0–340 min); however, only chickpeas, lentils and navy beans reduced pre-pizza meal BG AUC (0–260 min) relative to pasta and sauce. Chickpeas led to lower post-pizza meal BG AUC (260–340 min) compared to navy beans and yellow peas. Consumption of pulses in a high-glycaemic meal contributes to earlier satiation, lower BG following the meal and after a later meal, but these effects are specific to pulse type and cannot be explained by their glycaemic properties alone.
Mobile robot systems are being used more often in tasks that protect human operators from dangerous environments, but these benefits can be easily lost if the robots spend much of their time being repaired. This implies that any increment in their reliability will also improve their benefits. One way to achieve this is by adding redundant elements to the robot, but this adds complexity and cost to the design. On the other hand, cooperative mobile robots formed by members with the same basic structure provide a natural redundancy of elements, which may be used for reliability improvement. This work presents an architecture that takes advantage of the analytical and sensor redundancy present in groups of cooperative mobile robots in order to increase the reliability of the whole system. First, the design of the architecture is portrayed and the faults to be detected are described. The different layers of the system are then explained and analyzed using several simulations to test their capabilities and limitations. Finally, the experimental results on a group of small mobile robots are shown, validating the results delivered by simulations. These results show that the proposed architecture is able to detect and isolate correctly most of the faults tested.
This paper describes a complete laser-based approach for tracking the pose of a robot in a dynamic environment. The main novelty of this approach is that the matching between consecutively acquired scans is achieved using their associated curvature-based representations. The proposed scan matching algorithm consists of three stages. Firstly, the whole raw laser data is segmented into groups of consecutive range readings using a distance-based criterion and the curvature function for each group is computed. Then, this set of curvature functions is matched to the set of curvature functions associated to the previously acquired laser scan. Finally, characteristic points of pairwise curvature functions are matched and used to correctly obtain the best local alignment between consecutive scans. A closed form solution is employed for computing the optimal transformation and minimizing the robot pose shift error without iterations. Thus, the system is outstanding in terms of accuracy and computation time. The implemented algorithm is evaluated and compared to three state of the art scan matching approaches.
This paper reviews the handling of water and electrolytes by the ageing kidney and the clinical consequences in everyday clinical practice. Normal physiology in the adult kidney is discussed, followed by description of the main physiological changes (adaption) that occur as the kidney ages. Clearly, successful management of the elderly patient requires a knowledge of these changes, which result in: (i) increased tendency for volume depletion and dehydration; (ii) decreased ability to tolerate a volume load; (iii) increased propensity for potassium disturbances (hypo- and hyperkalaemia); (iv) diminished production of renin and blunted physiological response to the effects of aldosterone and antidiuretic hormone; (v) increased tendency to lower levels of phosphate; and (vi) tendency for the development of hypocalcaemia and hypomagnesaemia. A brief review of the role of extracellular fluid volume depletion and other factors contributing to acute renal failure in elderly patients is also presented.
Introduction. Tejocote (Crataegus spp.) is an edible fruit species that some Mesoamerican cultures have cultivated since pre-Hispanic times in Mexico; however, this fruit crop has not undergone formal breeding. It is unknown whether morphological markers associated with fruit size exist to be used for indirect selection; this could be important, because this species has a large cycle. Our research aimed at studying phenotypic correlations between leaf and stomata characters with fruit weight; such correlations might be used as morphological markers for selection of superior germplasm for fruit weight. Materials and methods. Pearson’s correlation coefficients of 36 leaf variables and three leaf stomata variables with fruit weight were calculated in 94 genotypes of four different species. Results. As expected, the correlations calculated for each species and for the species pool differed. However, the number of veins in leaves of reproductive shoots was positively correlated with fruit weight (P ≤ 0.05) in the two most important horticultural species. On the other hand, C. mexicana was the best option for selecting superior germplasm, and the most significant variables correlated with fruit weight in this species were leaf major axis length of large vegetative shoots, leaf elongation ratio and number of veins of reproductive shoot leaves. Discussion. These variables could be good selection indices or morphological markers that can be used for early screening of germplasm for yield potential.
This paper will review some fundamentals of normal renal physiology necessary to understand the changes occurring with age and enable the reader to distinguish between chronic renal insufficiency and the consequences of normal ageing on kidney function.