2,541 research outputs found
Utilisation of Mucuna Beans (Mucuna pruriens (L.) DC ssp. deeringianum (Bart) Hanelt) to Feed Growing Broilers
Performance of broilers fed on diets containing mucuna beans (MB) (Mucuna pruriens (L.) DC ssp. deeringianum (Bart) Hanelt) with different treatments were studied in three experiments. First experiment: three sorghum diets using 0 and 280g/kg of MB raw or soaked were evaluated. Second experiment: three sorghum diets using 0 and 280g/kg of MB raw or boiled were evaluated. Third experiment: six maize diets: maize only, three diets containing 280g/kg of MB raw, soaked or boiled, one containing soybean and a balanced diet (control) were evaluated. Experiment one: the birds fed on the 0g MB/kg showed a higher live weight gain (LWG) and a lower feed:gain ratio (FG) (p 0.01) than birds fed on the MB diets. There were no differences for any of the variables studied between the birds fed on the MB diets. Experiment two: the birds fed on the 0g MB/kg performed better (p 0.01) than birds fed on the MB diets. However, birds fed on the boiled MB diet had a higher LWG and a lower FG (p 0.01) than birds fed on the raw and soaked MB diet. Experiment three: the birds fed on the control diet obtained a higher LWG (p 0.01) than birds fed on the remainder treatments. The birds fed on the raw MB diet had a lower FG (p 0.01) than birds on the remainder treatments. However, birds fed on the boiled MB had a higher LWG and feed intake than birds fed on raw and soaked MB diets and only maize diet (p 0.01), but, lower (p 0.01) in comparison to birds fed on the soybean diet. The birds on the raw and soaked MB diets performed worst (p 0.01), even in comparison to birds fed on only maize (p 0.01). The results from these experiments indicated that inclusion of 280g MB/kg in the diet affected adversely the poultry performance. However, utilisation of MB boiled improved the broilers performance compared to birds fed on the raw and soaked MB diets
Snapshots of a molecular swivel in action
Members of the serine family of site-specific recombinases exchange DNA strands via 180° rotation about a central protein-protein interface. Modeling of this process has been hampered by the lack of structures in more than one rotational state for any individual serine recombinase. Here we report crystal structures of the catalytic domains of four constitutively active mutants of the serine recombinase Sin, providing snapshots of rotational states not previously visualized for Sin, including two seen in the same crystal. Normal mode analysis predicted that each tetramer's lowest frequency mode (i.e. most accessible large-scale motion) mimics rotation: two protomers rotate as a pair with respect to the other two. Our analyses also suggest that rotation is not a rigid body movement around a single symmetry axis but instead uses multiple pivot points and entails internal motions within each subunit
Unveiling the mechanisms of solid-state dewetting in Solid Oxide Cells with novel 2D electrodes
During the operation of Solid Oxide Cell (SOC) fuel electrodes, the mobility of nickel can lead to significant changes in electrode morphology, with accompanying degradation in electrochemical performance. In this work, the dewetting of nickel films supported on yttriastabilized zirconia (YSZ), hereafter called 2D cells, is studied by coupling in-situ environmental scanning electron microscopy (E-SEM), image analysis, cellular automata simulation and electrochemical impedance spectroscopy (EIS). Analysis of experimental E-SEM images shows that Ni dewetting causes an increase in active triple phase boundary (aTPB) length up to a maximum, after which a sharp decrease in aTPB occurs due to Ni de-percolation. This microstructural evolution is consistent with the EIS response, which shows a minimum in polarization resistance followed by a rapid electrochemical degradation. These results reveal that neither evaporation-condensation nor surface diffusion of Ni are the main mechanisms of dewetting at 560-800 °C. Rather, the energy barrier for pore nucleation within the dense Ni film appears to be the most important factor. This sheds light on the relevant mechanisms and interfaces that must be controlled to reduce the electrochemical degradation of SOC electrodes induced by Ni dewetting
The Non-thermal Radio Jet Toward the NGC 2264 Star Formation Region
We report sensitive VLA 3.6 cm radio observations toward the head of the Cone
nebula in NGC 2264, made in 2006. The purpose of these observations was to
study a non-thermal radio jet recently discovered, that appears to emanate from
the head of the Cone nebula. The jet is highly polarized, with well-defined
knots, and one-sided. The comparison of our images with 1995 archive data
indicates no evidence of proper motions nor polarization changes. We find
reliable flux density variations in only one knot, which we tentatively
identify as the core of a quasar or radio galaxy. An extragalactic location
seems to be the best explanation for this jet.Comment: 12 pages, 5 figure
Presence of Clostridium difficile in pig faecal samples and wild animal species associated with pig farms
Aims: to determine the presence of Clostridium difficile on fattening pig farms in north-eastern Spain. Methods and results: Twenty-seven farms were sampled. Pools of pig faecal samples (n = 210), samples of intestinal content from common farm pest species (n = 95) and environment-related samples (n = 93) were collected. Isolates were tested for toxin genes of C. difficile, and typed by PCR-ribotyping and toxinotyping. The minimal inhibitory concentrations of six antimicrobial agents were determined using Etest. Thirty-four isolates were obtained from 12 farms, and 30 (88·2%) had toxin genes. Seven ribotypes were identified. Ribotype 078 and its variant 126 were predominant (52·9%). The same ribotypes were isolated from different animal species on the same farm. None of the isolates were resistant to metronidazole or vancomycin. Conclusions: Clostridium difficile was common within the pig farm environment. Most of the positive samples came from pest species or were pest-related environmental samples. Significance and Impact of the Study: Pest species were colonized with toxigenic and antimicrobial-resistant C. difficile strains of the same ribotypes that are found in humans and pigs. Rodents and pigeons may transmit toxigenic and antimicrobial-resistant C. difficile strains that are of the same ribotypes as those occuring in humans
Hispanic Immigration to the United States
This chapter presents some of the exceptional characteristics of recent Hispanic immigration to the United States. In 2005, there were nearly 40 million Hispanic immigrants and descendants of Hispanic immigrants living in the U.S. The assimilation experience of this large cultural group does not seem to be following the path past immigrants to the U.S. followed. Most third generation Hispanics in the U.S. still find themselves with income and education levels below the U.S. averages. Most forecasts predict that about 60 million Hispanics and Hispanic-Americans will be living in the U.S. by 2030
A massive cluster of Red Supergiants at the base of the Scutum-Crux arm
We report on the unprecedented Red Supergiant (RSG) population of a massive
young cluster, located at the base of the Scutum-Crux Galactic arm. We identify
candidate cluster RSGs based on {\it 2MASS} photometry and medium resolution
spectroscopy. With follow-up high-resolution spectroscopy, we use CO-bandhead
equivalent width and high-precision radial velocity measurements to identify a
core grouping of 26 physically-associated RSGs -- the largest such cluster
known to-date. Using the stars' velocity dispersion, and their inferred
luminosities in conjuction with evolutionary models, we argue that the cluster
has an initial mass of 40,000\msun, and is therefore among the most
massive in the galaxy. Further, the cluster is only a few hundred parsecs away
from the cluster of 14 RSGs recently reported by Figer et al (2006). These two
RSG clusters represent 20% of all known RSGs in the Galaxy, and now offer the
unique opportunity to study the pre-supernova evolution of massive stars, and
the Blue- to Red-Supergiant ratio at uniform metallicity. We use GLIMPSE,
MIPSGAL and MAGPIS survey data to identify several objects in the field of the
larger cluster which seem to be indicative of recent region-wide starburst
activity at the point where the Scutum-Crux arm intercepts the Galactic bulge.
Future abundance studies of these clusters will therefore permit the study of
the chemical evolution and metallicity gradient of the Galaxy in the region
where the disk meets the bulge.Comment: 49 pages, 22 figures. Accepted for publication in ApJ. Version with
hi-res figures can be found at http://www.cis.rit.edu/~bxdpci/RSGC2.pd
Scale-free correlations in the dynamics of a small (N ~ 10000) cortical network
The advent of novel opto-genetics technology allows the recording of brain
activity with a resolution never seen before. The characterisation of these
very large data sets offers new challenges as well as unique theory-testing
opportunities. Here we discuss whether the spatial and temporal correlation of
the collective activity of thousands of neurons are tangled as predicted by the
theory of critical phenomena. The analysis shows that both, the correlation
length and the correlation time scale as predicted as a function
of the system size. With some peculiarities that we discuss, the analysis
uncovers new evidence consistent with the view that the large scale brain
cortical dynamics corresponds to critical phenomena.Comment: 8 pages, 6 figure
Transcriptome analyses identify five transcription factors differentially expressed in the hypothalamus of post-versus prepubertal Brahman heifers
Puberty onset is a developmental process influenced by genetic determinants, environment, and nutrition. Mutations and regulatory gene networks constitute the molecular basis for the genetic determinants of puberty onset. The emerging knowledge of these genetic determinants presents opportunities for innovation in the breeding of early pubertal cattle. This paper presents new data on hypothalamic gene expression related to puberty in Bos indicus (Brahman) in age-and weight-matched heifers. Six postpubertal heifers were compared with 6 prepubertal heifers using whole-genome RNA sequencing methodology for quantification of global gene expression in the hypothalamus. Five transcription factors (TF) with potential regulatory roles in the hypothalamus were identified in this experiment: E2F8, NFAT5, SIX5, ZBTB38, and ZNF605. These TF genes were significantly differentially expressed in the hypothalamus of postpubertal versus prepubertal heifers and were also identified as significant according to the applied regulatory impact factor metric (P < 0.05). Two of these 5 TF, ZBTB38 and ZNF605, were zinc fingers, belonging to a gene family previously reported to have a central regulatory role in mammalian puberty. The SIX5 gene belongs to the family of homologues of Drosophila sine oculis (SIX) genes implicated in transcriptional regulation of gonadotrope gene expression. Tumor-related genes such as E2F8 and NFAT5 are known to affect basic cellular processes that are relevant in both cancer and developmental processes. Mutations in NFAT5 were associated with puberty in humans. Mutations in these TF, together with other genetic determinants previously discovered, could be used in genomic selection to predict the genetic merit of cattle (i.e., the likelihood of the offspring presenting earlier than average puberty for Brahman). Knowledge of key mutations involved in genetic traits is an advantage for genomic prediction because it can increase its accuracy
- …