8 research outputs found
A Compact Dication Source for Ba Tagging and Heavy Metal Ion Sensor Development
We present a tunable metal ion beam that delivers controllable ion currents
in the picoamp range for testing of dry-phase ion sensors. Ion beams are formed
by sequential atomic evaporation and single or multiple electron impact
ionization, followed by acceleration into a sensing region. Controllability of
the ionic charge state is achieved through tuning of electrode potentials that
influence the retention time in the ionization region. Barium, lead, and cobalt
samples have been used to test the system, with ion currents identified and
quantified using a quadrupole mass analyzer. Realization of a clean
ion beam within a bench-top system represents an important
technical advance toward the development and characterization of barium tagging
systems for neutrinoless double beta decay searches in xenon gas. This system
also provides a testbed for investigation of novel ion sensing methodologies
for environmental assay applications, with dication beams of Pb and
Cd also demonstrated for this purpose
Avaliação nutricional e energética do farelo de girassol para aves Nutritional and energetic evaluation of sunflower meal in broiler diets
Foram realizados dois ensaios de metabolismo a fim de determinar a energia metabolizável aparente (EMA), por meio do método de coleta total de excretas com frangos, e a energia metabolizável verdadeira (EMV) e a digestibilidade verdadeira dos aminoácidos do farelo de girassol, por meio do método de alimentação forçada com galos cecectomizados. No primeiro ensaio, foi utilizado o delineamento experimental inteiramente ao acaso com 80 frangos Cobb, distribuídos em dois tratamentos, ração referência (RR) e RR mais 20% de inclusão de farelo de girassol e oito repetições e cinco aves por unidade experimental. No segundo ensaio, foi utilizado o delineamento experimental inteiramente ao acaso com 14 galos Leghorn, distribuídos em dois tratamentos, farelo de girassol e jejum, sete repetições e um galo por unidade experimental. O farelo de girassol apresentou 90,0% de matéria seca, 28,1% de proteína bruta, 4.42kcal/kg de energia bruta, 22,4% de fibra bruta, 2,9% de extrato etéreo, 0,8% de fósforo e 0,3% de cálcio. A EMV, a EMV corrigida, a EMA e a EMA corrigida determinadas foram 3.013; 2.200; 2.141 e 1.983kcal/kg, respectivamente. A lisina foi o aminoácido essencial que apresentou a menor digestibilidade e a arginina, a maior.Two experiments were carried out to determine apparent metabolizable energy (AME), by the method of total excreta collection using broilers; and true metabolizable energy (TME) and true amino acid digestibility of sunflower meal (SFM), by the method of forced feeding using cecectomized roosters. In the first experiment, a completely randomized experimental design, with two treatments (reference diet (RD) and RD plus 20% SFM inclusion) with eight replicates of five birds each, was applied. In the second experiment, a completely randomized experimental design, with two treatments (SFM vs. fasting) with seven replicates of one rooster each, was used. Sunflower meal presented 90,0% dry matter, 28.1% crude protein, 4,429kcal/kg crude energy, 22.4% crude fiber, 2.9% ether extract, 0.8% phosphorus, and 0.3% calcium. TME, nitrogen-corrected TME, AME, and nitrogen-corrected AME were: 3,013; 2,200; 2,141; and 1,983 kcal/kg, respectively. Lysine was the essential amino acid that presented the lowest digestibility, and arginine, the highest. It is important to constantly upgrade energy and nutrient values of feedstuffs used in feed formulation to supply poultry nutritional requirements
A Novel Transforming Growth Factor-β Receptor-interacting Protein That Is Also a Light Chain of the Motor Protein Dynein
The phosphorylated, activated cytoplasmic domains of the transforming growth factor-β (TGFβ) receptors were used as probes to screen an expression library that was prepared from a highly TGFβ-responsive intestinal epithelial cell line. One of the TGFβ receptor-interacting proteins isolated was identified to be the mammalian homologue of the LC7 family (mLC7) of dynein light chains (DLCs). This 11-kDa cytoplasmic protein interacts with the TGFβ receptor complex intracellularly and is phosphorylated on serine residues after ligand-receptor engagement. Forced expression of mLC7-1 induces specific TGFβ responses, including an activation of Jun N-terminal kinase (JNK), a phosphorylation of c-Jun, and an inhibition of cell growth. Furthermore, TGFβ induces the recruitment of mLC7-1 to the intermediate chain of dynein. A kinase-deficient form of TGFβ RII prevents both mLC7-1 phosphorylation and interaction with the dynein intermediate chain (DIC). This is the first demonstration of a link between cytoplasmic dynein and a natural growth inhibitory cytokine. Furthermore, our results suggest that TGFβ pathway components may use a motor protein light chain as a receptor for the recruitment and transport of specific cargo along microtublules