266 research outputs found
Effect of dietary nitrogen level and source on mRNA expression of urea transporters in the rumen epithelium of fattening bulls
This paper aims to study the effect of the dietary treatments on mRNA expression of urea transporter B (UT-B) and some aquaporins (AQP) in rumen epithelium of Italian Simmental young bulls. Eighty animals allocated to 16 pens were fed from about 500 to 650 kg body weight with four experimental diets, which resulted from the combination of two crude protein levels (125 and 110 g/kg dry matter, diets M and L, respectively) and two nitrogen sources (soybean meal (SBM) or SBM partly replaced by an isonitrogenous mixture of corn and urea; diets −U and +U, respectively). At slaughtering samples of blood and rumen epithelium were collected from six bulls for each diet. Blood samples were analysed for haematological parameters and quantitative PCR was carried out on the mRNA extracted from the rumen epithelium samples. The bulls fed diets M had lower plasma concentrations of aspartate aminotransferase than those receiving diets L (78.9 vs. 88.3 U/l, p = 0.04). Plasma urea was higher (p = 0.03) for diets M and lower for diets +U (2.0 vs. 2.5 and 1.73 vs. 2.00 mmol/l, respectively, in M and L diets, p = 0.04). The effect of dietary treatments on rumen UT expression were limited to AQP3, which was down regulated (p = 0.01) in diets +U. Finally, a high positive correlation (R2 = 0.871) between the expressions of AQP7 and AQP10 was found. In conclusion, the AQP3 appears very responsive to dietary treatments and therefore it is a candidate to be further studied in rumen metabolism experiments. The close relationship between mRNA expression of AQP7 and AQP10 indicates a similar function of these two proteins
In vitro ammonia release of urea-treated high moisture barley and maize grain
Rumen nitrogen (N) release from ammoniated wet barley and
maize kernels by urea treatment (UT) at harvesting was studied. Untreated
samples (CTR) were compared to UT and to samples combined with urea just
before the experiment (UA). In Experiment 1, ground CTR, UT and UA samples
were fermented in a ruminal in vitro system, and ammonia of fermentation fluid
was analysed at 0, 2, 4, 6 and 8 h. The effect of incubation time was observed
as ammonia peaked at 4 h of fermentation (10.24 vs 9.01 and 7.20 mg \ub7 dl 121,
respectively at 0 and 8 h, P < 0.01). Also, the effect of treatment was stated when
UT released less ammonia than UA treatment (9.76 vs 10.52 mg \ub7 dl 121, P < 0.05),
while the CTR samples showed the least ammonia N concentrations (P < 0.01).
In Experiment 2, the water N solubility of CTR and UT of both cereal samples
prepared in three physical forms (whole grain, coarsely ground and milled) was
examined. Samples were incubated in flasks with distilled water for 1, 2, 4, 6
and 8 h and N was measured in filtered residues to calculate N solubility. The
UT samples, regardless cereal type, solubilised more N in the milled than in the
whole form with the coarse form in the middle (43.7 vs 15.3%, 32.4 vs 14.0%
and 20.3 vs 9.2% for milled, coarse and whole form, respectively; treatment
7 physical form interaction: P < 0.01). The N added to wet cereal kernels by
the urea treatment was released in the rumen fermentation liquid more slowly
than that simply added as urea before incubation. Based on solubility data, the
treated whole or cracked kernels exhibited a slower N release than milled ones
Wave attenuation and trapping in 3D printed cantilever-in-mass metamaterials with spatially correlated variability
Additive manufacturing has become a fundamental tool to fabricate and experimentally investigate mechanical metamaterials and phononic crystals. However, this manufacturing process produces spatially correlated variability that breaks the translational periodicity, which might compromise the wave propagation performance of metamaterials. We demonstrate that the vibration attenuation profile is strictly related to the spatial profile of the variability, and that there exists an optimal disorder degree below which the attenuation bandwidth widens; for high disorder levels, the band gap mistuning annihilates the overall attenuation. The variability also induces a spatially variant locally resonant band gap that progressively slow down the group velocity until an almost zero value, giving rise to wave trapping effect near the lower band gap boundary. Inspired by this wave trapping phenomenon, a rainbow metamaterial with linear spatial-frequency trapping is also proposed, which have potential applications in energy harvesting, spatial wave filtering and non-destructive evaluation at low frequency. This report provides a deeper understanding of the differences between numerical simulations using nominal designed properties and experimental analysis of metamaterials constructed in 3D printing. These analysis and results may extend to phononic crystals and other periodic systems to investigate their wave and dynamic performance as well as robustness under variability9COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPFUNDAÇÃO DE APOIO À PESQUISA DO DISTRITO FEDERAL - FAPDFsem informação2014/19054-6; 2015/15718-00193.001507/201
Heat stress and feeding behaviour of dairy cows in late lactation
Heat stress is one of the most important problems that dairy cows have to face and the use of cooling systems is becoming more and more important. The first reaction that has the animal to cope with the environmental variations is to modify its behaviour. This study was aimed to investigate the effect of heat stress and a cooling system on the feeding behaviour of Italian Holstein Friesian dairy cows in late lactation. Two experiments were performed. In the first experiment, eight dairy cows were firstly kept 7 d under thermoneutral condition, and then under mild heat stress (temperature humidity index, THI, ranging between 72 and 78) for others 7 d. The second experiment consisted of 8 dairy cows used in a two-period cross-over design where the treatment was the use or not of a sprinkler system for cooling cows under mild heat stress. Cows were equipped with a noseband pressure sensor able to detect rumination and eating time, number of rumination and eating chews, number of rumination boluses and rumination intensity. Heat stress reduced rumination time, number of rumination chews and boluses (p <.05), and tended to reduce the number of eating chews (p <.10). Cooled cows increased rumination and eating time (p <.05), rumination intensity (p <.01), and the number of rumination and eating chews (p <.05). In conclusion, feeding behaviour was deeply influenced even by mild heat stress, which was effectively improved by the use of a sprinkler system.HIGHLIGHTS Mild heat stress reduced rumination time, number of rumination chews and boluses of dairy cows in late lactation Cooling cows with sprinklers was effective in alleviating heat stress in terms of feeding behaviour
Humoral and T-Cell Mediated Response after the Third Dose of mRNA Vaccines in Patients with Systemic Lupus Erythematosus on Belimumab
Objective: To evaluate humoral and T-cell cellular-mediated immune response after three doses of SARS-CoV-2 mRNA vaccines in patients with systemic lupus erythematosus (SLE) under Belimumab. Patients and methods: 12 patients on Belimumab and 13 age-matched healthy volunteers were recruited. Patients were in remission or in low disease activity, and they were taking no corticosteroids or only low doses. None of the patients and controls had detectable anti-SARS-CoV-2 antibodies due to previous exposure to the virus. All the patients received three doses of mRNA anti-SARS-CoV-2 vaccines and the humoral and cellular-mediated response were tested 4 weeks after the second dose (T0), 6 months after the second dose (T1) and 4 weeks after the third dose (T2). Comparison with the control group was performed at time T0 (i.e., 4 weeks after the second dose). Total anti-SARS-CoV-2 RBD antibodies were analyzed using a diagnostic assay, while cellular-mediated response was evaluated using the interferon-gamma release assay (IGRA). Results: A humoral response was documented in all the patients at T0 (median 459; IQR 225.25–758.5), but the antibody titer significantly declined from T0 to T1 (median 44.7; IQR: 30.3–202; p = 0.0066). At T2, the antibody titer significantly increased from T1 (median 2500; IQR: 2500–2500), and it was not different from T0 (respectively p < 0.0001, p = 0.66). Cellular-mediated response significantly declined from T0 to T1 (p = 0.003) but not from T0 to T2 (p = 0.3). No differences were found between patients and controls at T0 as regards both humoral and cellular responses (p = 1.0 and p = 0.09 for humoral and cellular responses, respectively). Conclusion: The third dose of mRNA COVID-19 vaccine can restore both humoral and cellular immune response in SLE patients on Belimumab
Trend of decreasing length of cervical cone excision during the last 20 years
OBJECTIVE: The aim of the present investigation was to evaluate the cervical conizations performed in the last 20 years in a single institution, with a particular interest in analyzing the trend of the length of cone excisions.PATIENTS AND METHODS: A retrospective cohort study of women who underwent a CO2-laser cervical conization between January 1996 and December 2015. Cytological abnormalities on referral pap smear, colposcopic findings and pertinent clinical and socio-demographic characteristics of each woman were collected. In particular, the length of cone specimen was evaluated, taking into account all the factors potentially influencing the length of excision.RESULTS: A total of 1270 women who underwent cervical conization from January 1996 to December 2015 were included in the analysis. A mean cone length of 15.1 \ub1 5.7 mm was reported, and we observed a significant decrease in the length of cone excisions over the whole study period. Age (rpartial = 0.1543, p < 0.0001), see & treat procedure (rpartial = -0.1945, p < 0.0001) and grade II colposcopic findings (rpartial = 0.1540, p < 0.0001) were significantly associated with the length of cone excision on multivariate analysis.CONCLUSIONS: In the last 20 years, a significant decrease in the length of cone excision was observed. In our opinion, this can be due to the acquired awareness by the gynecologists of the potential disadvantages of wide cone excision in term of adverse obstetric outcomes in future pregnancies
3D rainbow phononic crystals for extended vibration attenuation bands
We hereby report for the first time on the design, manufacturing and testing of a three-dimensional (3D) nearly-periodic, locally resonant phononic crystal (PnC). Most of the research effort on PnCs and metamaterials has been focused on the enhanced dynamic properties arising from their periodic design. Lately, additive manufacturing techniques have made a number of designs with intrinsically complex geometries feasible to produce. These recent developments have led to innovative solutions for broadband vibration attenuation, with a multitude of potential engineering applications. The recently introduced concept of rainbow metamaterials and PnCs has shown a significant potential for further expanding the spectrum of vibration attenuation in such structures by introducing a gradient profile for the considered unit cells. Given the above, it is expected that designing non-periodic PnCs will attract significant attention from scientists and engineers in the years to come. The proposed nearly-periodic design is based on cuboid blocks connected by curved beams, with internal voids in the blocks being implemented to adjust the local masses and generate a 3D rainbow PnC. Results show that the proposed approach can produce lightweight PnCs of a simple, manufacturable design exhibiting attenuation bandwidths more than two times larger than the equivalent periodic designs of equal mass
A formal framework to prove the correctness of model driven engineering composition operators
International audienceCurrent trends in system engineering combine modeling, composition and verification technologies in order to harness their ever growing complexity. Each composition operator dedicated to a different modeling concern should be proven to be property preserving at assembly time. These proofs are usually burdensome with repetitive aspects. Our work targets the factorisation of these aspects relying on primitive generic composition operators used to express more sophisticated language specific ones. These operators are defined for languages expressed with OMG MOF metamodeling technologies. The proof are done with the Coq proof assistant relying on the Coq4MDE framework defined previously. These basic operators, Union and Substitution, are illustrated using the MOF Package Merge as composition operator and the preservation of model conformance as verified property
First Measurement of the Transverse Spin Asymmetries of the Deuteron in Semi-Inclusive Deep Inelastic Scattering
First measurements of the Collins and Sivers asymmetries of charged hadrons
produced in deep-inelastic scattering of muons on a transversely polarized
6-LiD target are presented. The data were taken in 2002 with the COMPASS
spectrometer using the muon beam of the CERN SPS at 160 GeV/c. The Collins
asymmetry turns out to be compatible with zero, as does the measured Sivers
asymmetry within the present statistical errors.Comment: 6 pages, 2 figure
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