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1.
Int J Tuberc Lung Dis ; 22(2): 133-138, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-29506609

RESUMO

SETTING: The first pillar in the World Health Organisation's (WHO's) End TB strategy is 'Integrated, patient-centred tuberculosis (TB) care and prevention'. However, what are patient- and people-centred care, and why are they important for TB care and prevention? OBJECTIVE AND RATIONALE: To define the concept of patient-centred care, the rationale for it, and its evolution into people-centred care; and to explore evidence on whether people-centred approaches work for TB and present key areas where continuous efforts are needed to support their implementation. RESULTS: Based on the reasoning and the evidence presented, we propose four areas where further action is needed to ensure that people-centred TB care and prevention can achieve their potential: 1) reaching consensus on definitions and terminology; 2) strengthening research; 3) using and evaluating new technology; and 4) nurturing country leadership and advocacy. CONCLUSION: Integrated, people-centred TB care and prevention should be a guiding light for all those involved in the quest to eliminate TB. However, much still needs to be done to bridge the gaps between the potential and actual performance of national programmes.


Assuntos
Prestação Integrada de Cuidados de Saúde , Modelos Organizacionais , Assistência Centrada no Paciente , Tuberculose Pulmonar/terapia , Saúde Global , Humanos , Tuberculose Pulmonar/prevenção & controle , Organização Mundial da Saúde
2.
Animal ; 10(11): 1803-1811, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27133467

RESUMO

Reduction of the CP content in the diets of piglets requires supplementation with crystalline essential amino acids (AA). Data on the leucine (Leu) and histidine (His) requirements of young pigs fed low-CP diets are limited and have primarily been obtained from nonlinear models. However, these models do not consider the possible decline in appetite and growth that can occur when pigs are fed excessive amounts of AA such as Leu. Therefore, two dose-response studies were conducted to estimate the standardised ileal digestible (SID) Leu : lysine (Lys) and His : Lys required to optimise the growth performance of young pigs. In both studies, the average daily gain (ADG), average daily feed intake (ADFI) and gain-to-feed ratio (G : F) were determined during a 6-week period. To ensure that the diets had sub-limiting Lys levels, a preliminary Lys dose-response study was conducted. In the Leu study, 60 35-day-old piglets of both sexes were randomly assigned to one of five treatments and fed a low-CP diet (15%) with SID Leu : Lys levels of 83%, 94%, 104%, 115% or 125%. The His study used 120 31-day-old piglets of both sexes, which were allotted to one of five treatments and fed a low-CP diet (14%) with SID His : Lys levels of 22%, 26%, 30%, 34% or 38%. Linear broken-line, curvilinear-plateau and quadratic-function models were used for estimations of SID Leu : Lys and SID His : Lys. The minimum SID Leu : Lys level needed to maximise ADG, ADFI and G : F was, on average, 101% based on the linear broken-line and curvilinear-plateau models. Using the quadratic-function model, the minimum SID Leu : Lys level needed to maximise ADG, ADFI and G : F was 108%. Data obtained from the quadratic-function analysis further showed that a ±10% deviation from the identified Leu requirement was accompanied by a small decline in the ADG (-3%). The minimum SID His : Lys level needed to maximise ADG, ADFI and G : F was 27% and 28% using the linear broken-line and curvilinear-plateau models, respectively, and 33% using the quadratic-function model. The preferred model to estimate the His requirement was the curvilinear-plateau model. However, a 10% reduction in the SID His : Lys level was associated with an 11% reduction in the ADG. In conclusion, the SID Leu : Lys level needed to maximise growth was 108% when using the quadratic-function model as the best-fitting model. The minimum SID His : Lys level required to optimise growth was 28% when using the curvilinear-plateau model as the best-fitting model.


Assuntos
Ração Animal/análise , Dieta com Restrição de Proteínas/veterinária , Histidina/administração & dosagem , Histidina/farmacologia , Leucina/administração & dosagem , Leucina/farmacologia , Suínos/crescimento & desenvolvimento , Suínos/metabolismo , Fenômenos Fisiológicos da Nutrição Animal/efeitos dos fármacos , Animais , Suplementos Nutricionais , Feminino , Histidina/metabolismo , Íleo/metabolismo , Leucina/metabolismo , Lisina/administração & dosagem , Lisina/metabolismo , Lisina/farmacologia , Masculino
3.
Poult Sci ; 95(3): 590-4, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26706358

RESUMO

The present study was performed to assess the bioefficacy of DL-methionine hydroxy analogue-free acid (MHA) in comparison to DL-methionine (DLM) as sources of methionine for growing male white Pekin ducks in the first 3 wk of life. For this aim, 580 1-day-old male ducks were allocated into 12 treatment groups and received a basal diet that contained 0.29% of methionine, 0.34% of cysteine and 0.63% of total sulphur containing amino acids or the same diet supplemented with either DLM or MHA in amounts to supply 0.05, 0.10, 0.15, 0.20, and 0.25% of methionine equivalents. Ducks fed the control diet without methionine supplement had the lowest final body weights, daily body weight gains and feed intake among all groups. Supplementation of methionine improved final body weights and daily body weight gains in a dose dependent-manner. There was, however, no significant effect of the source of methionine on all of the performance responses. Evaluation of the data of daily body weight gains with an exponential model of regression revealed a nearly identical efficacy (slope of the curves) of both compounds for growth (DLM = 100%, MHA = 101%). According to the exponential model of regression, 95% of the maximum values of daily body weight gain were reached at methionine supplementary levels of 0.080% and 0.079% for DLM and MHA, respectively. Overall, the present study indicates that MHA and DLM have a similar efficacy as sources of methionine for growing ducks. It is moreover shown that dietary methionine concentrations of 0.37% are required to reach 95% of the maximum of daily body weight gains in ducks during the first 3 wk of life.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Dieta/veterinária , Patos/metabolismo , Metionina/análogos & derivados , Metionina/metabolismo , Ração Animal/análise , Animais , Suplementos Nutricionais/análise , Patos/crescimento & desenvolvimento , Masculino , Aumento de Peso
4.
Poult Sci ; 94(10): 2404-13, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26240391

RESUMO

This study investigated the hypothesis that dietary fats rich in lauric (C12) and myristic acid (C14) increase broiler performance and that the underlying mechanism involves antimicrobial effects on gut bacteria and changes in gut morphology. One hundred eighty 1-day-old Cobb-500 broilers were allotted to 3 groups. All groups received a basal diet consisting of maize, wheat, soybean meal, and a fat source (4.5, 7.0, 7.6, and 8.0% of fat product in the diet during d 1 to 9, 10 to 17, 18 to 27, and 28 to 35, respectively) until 35 d of age. The diet of the control group contained a fat with 67% of oleic and linoleic acid and 1.4% of C12 and C14 of total fatty acids, that of the esterified lauric and myristic acid (ELA) group a fat with 33% of esterified C12 and C14 and that of the free lauric and myristic acid (FLA) group a fat with 31% of both esterified and free (1:1) C12 and C14 (6 replicates/treatment, 10 birds/replicate). Gain and feed consumption did not differ between groups, but feed:gain was lower in FLA group as compared to the control group (P < 0.05). Carcass weight, liver weight, triglyceride content of liver and muscle, and muscle cholesterol were similar between groups; however, breast muscle weight was higher in the FLA than in the control group (P < 0.05). The villus height:crypt depth ratio of the duodenal wall did not differ between groups, but in the jejunum, it was lower in the FLA group as compared to the control group (P < 0.05). DNA copy numbers of Lactobacillus, Bifidobacteria, Enterobacteria, Escherichia coli, and Campylobacter jejuni in jejunal digesta were similar among groups. The study shows that dietary fats rich in free C12 and C14 improved feed:gain and breast muscle yield, but the observed effects could not be conclusively explained based on the parameters measured. The decreased jejunal villi:crypt ratio may point to changes in gut protein or cell turnover.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Galinhas/fisiologia , Dieta/veterinária , Gorduras na Dieta/metabolismo , Ácidos Láuricos/metabolismo , Ácido Mirístico/metabolismo , Ração Animal/análise , Animais , Galinhas/anatomia & histologia , Galinhas/crescimento & desenvolvimento , Galinhas/microbiologia , Trato Gastrointestinal/microbiologia , Intestinos/anatomia & histologia , Intestinos/microbiologia , Masculino , Carne/análise , Microbiota
5.
Br Poult Sci ; 53(4): 431-8, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23130577

RESUMO

1. The effects of n-3 polyunsaturated fatty acids (PUFA) and conjugated linoleic acids (CLA) on genes involved in carnitine homeostasis were compared in laying hens. Three groups of laying hens were fed on a control diet or a diet with either 3% of fish oil or CLA for 4 weeks. 2. Feed intake and egg production rate did not differ between the three groups. Diets with fish oil or CLA had only a weak effect on mRNA levels of PPARα target genes (ACO, CPT-I) in the liver and did not influence mRNA concentrations of the most important carnitine transporter OCTN2, enzymes of involved in carnitine synthesis (TMLD, TMABA-DH, BBD) or concentrations of carnitine in plasma, liver and total egg contents. 3. Hens fed the CLA diet had lower concentrations of free and total carnitine in egg yolk but higher concentrations of carnitine in albumen than control hens (P < 0·05), whereas the amount of free and total carnitine in whole egg did not differ. 4. In conclusion, the study showed that feeding fish oil or CLA causes only a weak activation of PPARα in tissues of laying hens that probably explained the lack of effect on carnitine homeostasis. The results contrast with those in humans and mice that show a significant effect of synthetic PPARα agonists on carnitine homeostasis in humans and mice.


Assuntos
Carnitina/metabolismo , Galinhas/fisiologia , Suplementos Nutricionais/análise , Ácidos Graxos Ômega-3/administração & dosagem , Óleos de Peixe/administração & dosagem , Ácidos Linoleicos Conjugados/administração & dosagem , PPAR alfa/metabolismo , Ração Animal/análise , Animais , Transporte Biológico , Carnitina/biossíntese , Galinhas/genética , Dieta/veterinária , Feminino , Fígado/enzimologia , Especificidade de Órgãos , PPAR alfa/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Espectrometria de Massas em Tandem/veterinária , Regulação para Cima
6.
Eur Respir J ; 39(4): 807-19, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22467723

RESUMO

The European Centre for Disease Prevention and Control (ECDC) and the European Respiratory Society (ERS) jointly developed European Union Standards for Tuberculosis Care (ESTC) aimed at providing European Union (EU)-tailored standards for the diagnosis, treatment and prevention of tuberculosis (TB). The International Standards for TB Care (ISTC) were developed in the global context and are not always adapted to the EU setting and practices. The majority of EU countries have the resources and capacity to implement higher standards to further secure quality TB diagnosis, treatment and prevention. On this basis, the ESTC were developed as standards specifically tailored to the EU setting. A panel of 30 international experts, led by a writing group and the ERS and ECDC, identified and developed the 21 ESTC in the areas of diagnosis, treatment, HIV and comorbid conditions, and public health and prevention. The ISTCs formed the basis for the 21 standards, upon which additional EU adaptations and supplements were developed. These patient-centred standards are targeted to clinicians and public health workers, providing an easy-to-use resource, guiding through all required activities to ensure optimal diagnosis, treatment and prevention of TB. These will support EU health programmes to identify and develop optimal procedures for TB care, control and elimination.


Assuntos
Antituberculosos/uso terapêutico , Guias de Prática Clínica como Assunto/normas , Tuberculose Pulmonar/tratamento farmacológico , União Europeia , Humanos
7.
Animal ; 6(1): 70-8, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22436156

RESUMO

Supplementation of carnitine has been shown to improve performance characteristics such as protein accretion in growing pigs. The molecular mechanisms underlying this phenomenon are largely unknown. Based on recent results from DNA microchip analysis, we hypothesized that carnitine supplementation leads to a downregulation of genes of the ubiquitin proteasome system (UPS). The UPS is the most important system for protein breakdown in tissues, which in turn could be an explanation for increased protein accretion. To test this hypothesis, we fed sixteen male, four-week-old piglets either a control diet or the same diet supplemented with carnitine and determined the expression of several genes involved in the UPS in the liver and skeletal muscle. To further determine whether the effects of carnitine on the expression of genes of the UPS are mediated directly or indirectly, we also investigated the effect of carnitine on the expression of genes of the UPS in cultured C2C12 myotubes and HepG2 liver cells. In the liver of piglets fed the carnitine-supplemented diet, the relative mRNA levels of atrogin-1, E214k and Psma1 were lower than in those of the control piglets (P < 0.05). In skeletal muscle, the relative mRNA levels of atrogin-1, MuRF1, E214k, Psma1 and ubiquitin were lower in piglets fed the carnitine-supplemented diet than that in control piglets (P < 0.05). Incubating C2C12 myotubes and HepG2 liver cells with increasing concentrations of carnitine had no effect on basal and/or hydrocortisone-stimulated mRNA levels of genes of the UPS. In conclusion, this study shows that dietary carnitine decreases the transcript levels of several genes involved in the UPS in skeletal muscle and liver of piglets, whereas carnitine has no effect on the transcript levels of these genes in cultivated HepG2 liver cells and C2C12 myotubes. These data suggest that the inhibitory effect of carnitine on the expression of genes of the UPS is mediated indirectly, probably via modulating the release of inhibitors of the UPS such as IGF-1. The inhibitory effect of carnitine on the expression of genes of the UPS might explain, at least partially, the increased protein accretion in piglets supplemented with carnitine.


Assuntos
Carnitina/administração & dosagem , Complexo de Endopeptidases do Proteassoma/genética , Suínos/fisiologia , Ubiquitina/genética , Complexo Vitamínico B/administração & dosagem , Análise de Variância , Animais , Linhagem Celular , Regulação para Baixo , Regulação da Expressão Gênica/efeitos dos fármacos , Células Hep G2 , Humanos , Fígado/metabolismo , Masculino , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , RNA Mensageiro/análise , RNA Mensageiro/isolamento & purificação , Suínos/genética , Ubiquitina/metabolismo
8.
Phys Rev Lett ; 106(12): 122501, 2011 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-21517310

RESUMO

The masses of ten proton-rich nuclides, including the N=Z+1 nuclides 85Mo and 87Tc, were measured with the Penning trap mass spectrometer SHIPTRAP. Compared to the Atomic Mass Evaluation 2003 a systematic shift of the mass surface by up to 1.6 MeV is observed causing significant abundance changes of the ashes of astrophysical x-ray bursts. Surprisingly low α separation energies for neutron-deficient Mo and Tc are found, making the formation of a ZrNb cycle in the rp process possible. Such a cycle would impose an upper temperature limit for the synthesis of elements beyond Nb in the rp process.

9.
Phys Rev Lett ; 106(5): 052504, 2011 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-21405389

RESUMO

In the search for the nuclide with the largest probability for neutrinoless double-electron capture, we have determined the Q(ϵϵ) value between the ground states of (152)Gd and (152)Sm by Penning-trap mass-ratio measurements. The new Q(ϵϵ) value of 55.70(18) keV results in a half-life of 10(26) yr for a 1 eV neutrino mass. With this smallest half-life among known 0νϵϵ transitions, (152)Gd is a promising candidate for the search for neutrinoless double-electron capture.

10.
Eur J Mass Spectrom (Chichester) ; 16(3): 269-82, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20530821

RESUMO

Mass spectrometry for fundamental studies in metrology and atomic, nuclear and particle physics requires extreme sensitivity and efficiency as well as ultimate resolving power and accuracy. An overview will be given on the global status of high-accuracy mass spectrometry for fundamental physics and metrology. Three quite different examples of modern mass spectrometric experiments in physics are presented: (i) the retardation spectrometer KATRIN at the Forschungszentrum Karlsruhe, employing electrostatic filtering in combination with magnetic-adiabatic collimation-the biggest mass spectrometer for determining the smallest mass, i.e. the mass of the electron anti-neutrino, (ii) the Experimental Cooler-Storage Ring at GSI-a mass spectrometer of medium size, relative to other accelerators, for determining medium-heavy masses and (iii) the Penning trap facility, SHIPTRAP, at GSI-the smallest mass spectrometer for determining the heaviest masses, those of super-heavy elements. Finally, a short view into the future will address the GSI project HITRAP at GSI for fundamental studies with highly-charged ions.

11.
Rev Sci Instrum ; 81(2): 02A515, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20192370

RESUMO

The improvement in the performance of a conventional laser ion source in the laser ion source and trap (LIST) project is presented, which envisages installation of a repeller electrode and a linear Paul trap/ion guide structure. This approach promises highest isobaric purity and optimum temporal and spatial control of the radioactive ion beam produced at an online isotope separator facility. The functionality of the LIST was explored at the offline test separators of University of Mainz (UMz) and ISOLDE/CERN, using the UMz solid state laser system. Ionization efficiency and selectivity as well as time structure and transversal emittance of the produced ion beam was determined. Next step after complete characterization is the construction and installation of the radiation-hard final trap structure and its first online application.

12.
Nature ; 463(7282): 785-8, 2010 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-20148034

RESUMO

The mass of an atom incorporates all its constituents and their interactions. The difference between the mass of an atom and the sum of its building blocks (the binding energy) is a manifestation of Einstein's famous relation E = mc(2). The binding energy determines the energy available for nuclear reactions and decays (and thus the creation of elements by stellar nucleosynthesis), and holds the key to the fundamental question of how heavy the elements can be. Superheavy elements have been observed in challenging production experiments, but our present knowledge of the binding energy of these nuclides is based only on the detection of their decay products. The reconstruction from extended decay chains introduces uncertainties that render the interpretation difficult. Here we report direct mass measurements of trans-uranium nuclides. Located at the farthest tip of the actinide species on the proton number-neutron number diagram, these nuclides represent the gateway to the predicted island of stability. In particular, we have determined the mass values of (252-254)No (atomic number 102) with the Penning trap mass spectrometer SHIPTRAP. The uncertainties are of the order of 10 keV/c(2) (representing a relative precision of 0.05 p.p.m.), despite minute production rates of less than one atom per second. Our experiments advance direct mass measurements by ten atomic numbers with no loss in accuracy, and provide reliable anchor points en route to the island of stability.

13.
Rev Sci Instrum ; 81(1): 013301, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20113087

RESUMO

The interest to produce negative osmium ions is manifold in the realm of high-accuracy ion trap experiments: high-resolution nearly Doppler-free laser spectroscopy, antihydrogen formation in its ground state, and contributions to neutrino mass spectrometry. Production of these ions is generally accomplished by sputtering an Os sample with Cs(+) ions at tens of keV. Though this is a well-established method commonly used at accelerators, these kind of sources are quite demanding and tricky to operate. Therefore, the development of a more straightforward and cost effective production scheme will be of benefit for ion trap and other experiments. Such a scheme makes use of desorption and ionization with pulsed lasers and identification of the ions by time-of-flight mass spectrometry. First investigations of negative osmium ion production using a pulsed laser for desorption and ionization and a commercial matrix-assisted laser desorption/ionization time-of-flight system for identification has demonstrated the suitability of this technique. More than 10(3) negative osmium ions per shot were registered after bombarding pure osmium powder with a 5 ns pulse width Nd:yttrium aluminum garnet laser. The limitation in the ion number was imposed by the detection limit of the microchannel plate detector.

14.
J Anim Physiol Anim Nutr (Berl) ; 93(4): 400-9, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18522687

RESUMO

This study was performed to assess the effects of potato protein and fish protein on concentrations of lipids in plasma and lipoproteins and the expression of genes involved in lipid metabolism in pigs used as an animal model. Therefore, 27 young male pigs with an average body weight of 22 kg were fed diets supplemented with protein extracted from potatoes (containing 849 g protein/kg dry matter), Alaska Pollack fillet as a source of fish protein (containing 926 g crude protein/kg dry matter) or casein which was used as control, for 3 weeks. Diets were formulated to supply identical amounts of each protein to the pigs by the three protein sources, namely 116 g/day in first week and 150 g/day in the second and third week. Pigs fed potato protein had lower concentrations of cholesterol in plasma and LDL than pigs fed casein (p < 0.05); no effect was observed on concentrations of HDL cholesterol and triglycerides. Pigs fed fish protein had lower cholesterol concentrations in plasma, LDL and HDL, and lower triglyceride concentrations in triglyceride-rich lipoproteins than pigs fed casein (p < 0.05). mRNA concentrations of genes involved in bile acid synthesis and cholesterol uptake were higher in pigs fed fish protein than in pigs fed casein (p < 0.05); no effect on these genes was observed in pigs fed potato protein. Expression of genes involved in lipogenesis and fatty acid oxidation was not altered by fish protein. In conclusion, this study shows that fish protein and potato protein lower plasma cholesterol concentrations in pigs. The hypocholesterolaemic effect of fish protein might be in part caused by a stimulation of bile acid synthesis; the reason for the hypocholesterolaemic effect of potato protein requires further elucidation.


Assuntos
Ração Animal/análise , Proteínas de Peixes/farmacologia , Lipídeos/sangue , Proteínas de Plantas/farmacologia , Solanum tuberosum/química , Suínos/sangue , Fenômenos Fisiológicos da Nutrição Animal , Animais , Peso Corporal/efeitos dos fármacos , Colesterol/sangue , Colesterol/metabolismo , Dieta/veterinária , Proteínas de Peixes/metabolismo , Hipolipemiantes/farmacologia , Lipoproteínas/sangue , Lipoproteínas/metabolismo , Fígado/anatomia & histologia , Fígado/metabolismo , Masculino , Proteínas de Plantas/metabolismo , Triglicerídeos/sangue , Triglicerídeos/metabolismo
15.
Phys Rev Lett ; 101(25): 252502, 2008 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-19113701

RESUMO

High-precision mass and charge radius measurements on ;{17-22}Ne, including the proton-halo candidate 17Ne, have been performed with Penning trap mass spectrometry and collinear laser spectroscopy. The 17Ne mass uncertainty is improved by factor 50, and the charge radii of ;{17-19}Ne are determined for the first time. The fermionic molecular dynamics model explains the pronounced changes in the ground-state structure. It attributes the large charge radius of 17Ne to an extended proton configuration with an s;{2} component of about 40%. In 18Ne the smaller radius is due to a significantly smaller s;{2} component. The radii increase again for ;{19-22}Ne due to cluster admixtures.

16.
Phys Rev Lett ; 100(7): 072501, 2008 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-18352543

RESUMO

A high-precision direct Penning trap mass measurement has revealed a 0.5-MeV deviation of the binding energy of (134)Sn from the currently accepted value. The corrected mass assignment of this neutron-rich nuclide restores the neutron-shell gap at N=82, previously considered to be a case of "shell quenching." In fact, the new shell gap value for the short-lived (132)Sn is larger than that of the doubly magic (48)Ca which is stable. The N=82 shell gap has considerable impact on fission recycling during the r process. More generally, the new finding has important consequences for microscopic mean-field theories which systematically deviate from the measured binding energies of closed-shell nuclides.

17.
Phys Rev Lett ; 100(7): 073201, 2008 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-18352547

RESUMO

Isotope shifts in dielectronic recombination spectra were studied for Li-like (A)Nd(57+) ions with A=142 and A=150. From the displacement of resonance positions energy shifts deltaE(142 150)(2s-2p(1/2))=40.2(3)(6) meV [(stat)(sys)] and deltaE(142 150)(2s-2p(3/2))=42.3(12)(20) meV of 2s-2p(j) transitions were deduced. An evaluation of these values within a full QED treatment yields a change in the mean-square charge radius of (142 150)deltar(2)=-1.36(1)(3) fm(2). The approach is conceptually new and combines the advantage of a simple atomic structure with high sensitivity to nuclear size.

18.
Phys Rev Lett ; 100(1): 012501, 2008 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-18232754

RESUMO

The masses of six neutron-deficient rare holmium and thulium isotopes close to the proton drip line were determined with the SHIPTRAP Penning trap mass spectrometer. For the first time the masses of the proton-unbound isotopes 144,145Ho and 147,148Tm were directly measured. The proton separation energies were derived from the measured mass values and compared to predictions from mass formulas. The new values of the proton separation energies are used to determine the location of the proton drip line for holmium and thulium more accurately.

19.
Phys Rev Lett ; 101(26): 262501, 2008 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-19437636

RESUMO

High-precision mass measurements on neutron-rich zinc isotopes (71m,72-81)Zn have been performed with the Penning trap mass spectrometer ISOLTRAP. For the first time, the mass of 81Zn has been experimentally determined. This makes 80Zn the first of the few major waiting points along the path of the astrophysical rapid neutron-capture process where neutron-separation energy and neutron-capture Q-value are determined experimentally. The astrophysical conditions required for this waiting point and its associated abundance signatures to occur in r-process models can now be mapped precisely. The measurements also confirm the robustness of the N=50 shell closure for Z=30.

20.
Poult Sci ; 86(6): 1187-95, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17495091

RESUMO

Expression of peroxisome proliferator-activated receptor-alpha (PPARalpha) has been shown in liver of chicks, but effects of its activation have not yet been investigated. In this study, laying hens were treated with clofibrate, a synthetic PPARalpha agonist, to investigate the effects of PPARalpha activation on liver lipid metabolism. Hens receiving a diet containing 5 g of clofibrate/kg had a lower food intake and higher liver mRNA concentrations of typical PPARalpha target genes (carnitine palmitoyltransferase 1A, acyl-coenzyme A oxidase, bifunctional enzyme, lipoprotein lipase) involved in hepatic mitochondrial and peroxisomal beta-oxidation and plasma triglyceride clearance than control hens that received the same diet without clofibrate (P<0.05). Hens treated with clofibrate also had lower mRNA concentrations of fatty acid synthase, 3-hydroxy-3-methylglutaryl-coenzyme A reductase, and low-density lipoprotein receptor, proteins involved in fatty acid biosynthesis and cholesterol biosynthesis and uptake, than hens fed the control diet (P<0.05). These changes in clofibrate-treated hens were accompanied by reduced liver triglyceride concentrations, strongly diminished very low density triglyceride and cholesterol concentrations (P<0.05), a disturbed maturation of egg follicles, a complete stop of egg production, and a markedly reduced plasma 17-beta-estradiol concentration (P<0.05). In conclusion, it is shown that clofibrate has complex effects on hepatic lipid metabolism in laying hens that mimic PPARalpha activation in mammals, affect maturation of egg follicles, and lead to a stop of egg production. Because clofibrate treatment strongly reduced food intake in the hens, some of these effects (i.e., egg production) may have been due to a low energy and nutrient intake.


Assuntos
Galinhas/metabolismo , Clofibrato/farmacologia , Hipolipemiantes/farmacologia , Oviposição/fisiologia , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Animais , Peso Corporal/efeitos dos fármacos , Colesterol/sangue , Colesterol/metabolismo , Dieta/veterinária , Gema de Ovo/química , Gema de Ovo/efeitos dos fármacos , Estradiol/sangue , Ácidos Graxos/metabolismo , Comportamento Alimentar/efeitos dos fármacos , Feminino , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Oviposição/efeitos dos fármacos , PPAR alfa/metabolismo , Triglicerídeos/sangue , Triglicerídeos/metabolismo
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