482 research outputs found

    Evidence of Luttinger liquid behavior in one-dimensional dipolar quantum gases

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    The ground state and structure of a one-dimensional Bose gas with dipolar repulsions is investigated at zero temperature by a combined Reptation Quantum Monte Carlo (RQMC) and bosonization approach. A non trivial Luttinger-liquid behavior emerges in a wide range of intermediate densities, evolving into a Tonks-Girardeau gas at low density and into a classical quasi-ordered state at high density. The density dependence of the Luttinger exponent is extracted from the numerical data, providing analytical predictions for observable quantities, such as the structure factor and the momentum distribution. We discuss the accessibility of such predictions in current experiments with ultracold atomic and molecular gases.Comment: 4 pages, 3 EPS figures, Revtex

    Effect of increasing dietary aminoacid concentration in late gestation on body condition and reproductive performance of hyperprolific sows

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    A total of 62 highly prolific Danbred sows was used to evaluate the implications of increasing dietary amino acid (AA) concentration during late gestation (from day 77 to 107 of pregnancy) on body condition and reproductive performances. Sows were assigned to one of the two treatments (n = 31, with similar number of sows in the second-, third-and fourth-cycle); control diet (containing 6 g of standardized ileal digestible lysine-SID Lys-)/kg) and high AA level (containing 10 g SID Lys/kg and following the ideal protein concept for the remaining essential AA). On day 108 of pregnancy, animals were moved to the farrowing-lactating facilities where they spent until weaning receiving a common standard lactation diet. After farrowing, litters were standardized to 13 piglets each. At 107 d of gestation, backfat depth was thicker in sows fed high AA concentration than in those fed control diet (p 0.05). Additionally, at farrowing, the litter size (p = 0.043) and weight (p = 0.017) were higher in sows fed high AA level. It can be concluded that the increase in the AA content in the feed during the last month of gestation could improve the body condition of the sows and their performance results

    Effects of Anthocyanin Supplementation and Ageing Time on the Volatile Organic Compounds and Sensory Attributes of Meat from Goat Kids

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    The aim of this study was to assess the effects of dietary anthocyanin addition on volatile compounds of meat from goat kids during ageing. For this work, 60 male and female kids were divided into two groups: red orange and lemon extract (RLE group; n = 30), which received an RLE extract (90 mg/kg of live weight); and control (CON group; n = 30). The phytoextract in dry powder form was rich in bioflavonoids such as flavanones (about 16%) and anthocyanins (about 3%). After slaughtering, the longissimus thoracis et lumborum muscle was aged at 4◩C. The volatile organic compound (VOC) and sensorial analyses were carried out at 1, 3 and 7 days. A total of 10 chemical families were identified during the ageing process. Aldehydes were the most abundant VOC, followed by ketones and alcohols. Their contents increased during the process, showing after 7 days of ageing mean values of 20,498, 2193 and 1879 ng/g of meat, respectively. Regarding dietary effects, carboxylic acids, hydrocarbons and thiols presented significant differences between treatments, with higher carboxylic acid contents observed in RLE samples (437 vs. 467 ng/g of meat for CON and RLE batches, respectively; p < 0.05). On the contrary, hydrocarbons (436 vs. 254 ng/g of meat for CON and RLE batches, respectively) and thiols (160 vs. 103 ng/g of meat for CON and RLE batches, respectively) displayed significantly (p < 0.01) higher amounts in CON compared to the RLE group. Regarding ageing time, the tenderness, juiciness, odour and overall assessment parameters showed significantly higher scores at the end of the whole process (p < 0.05). On the other hand, only odour displayed significant differences between treatments, reaching higher scores in CON samples (p < 0.05). Therefore, ageing time improved the sensorial properties (tenderness, juiciness, odour and overall assessment) and the VOC content, whereas the inclusion of anthocyanins in the kids’ diet did not have a great impact on the properties of aged meat

    Modulating the water oxidation catalytic activity of iridium complexes by functionalizing the Cp*-ancillary ligand: hints on the nature of the active species

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    The catalytic activity toward NaIO4driven water oxidation of a series of [RCp*IrCl(ÎŒ-Cl)]2dimeric precursors, containing tetramethylcyclopentadienyl ligands with a variable R substituent (H,1; Me,2; Et,3;nPr,4; CH2CH2NH3+,5; Ph,6; 4-C6H4F,7; 4-C6H4OH,8; Bn,9), has been evaluated at 298 K and pH = 7 (with phosphate buffer). For each dimer, the effect of changing the catalyst (1-10 ÎŒM) and NaIO4(5-40 mM) concentration has been studied. All precursors exhibit a high activity with TOF values ranging from 101 min−1to 393 min−1and TON values being always those expected assuming a 100% yield. The catalytic activity was strongly affected by the nature of the R substituent. The highest TOF values were observed when R was electron-donating and small. The results of multiple consecutive injection experiments suggest that a fragment of the initial C5Me4R, still bearing the R-substituent, remains attached at iridium in the active species, despite the oxidativein situdegradation of the same ligand. The decrease of TOF in the second and third catalytic runs was completely ascribed to a drop of the redox potential caused by the conversion of IO4−into IO3−, according to the Nernst equation. This hypothesis was verified by performing catalytic experiments in which the initial redox potential (ΔE) was deliberately varied by using water solutions of IO4−/IO3−mixtures at different relative concentrations. Consistently, TOFversusΔEplots show that, for a given catalyst, the same TOF is obtained at a certain redox potential, irrespective of the initial reaction conditions used. All seems to indicate that after a short activation period, during which the transformation of the precursors occurs, individual active species for each dimer form and remain the same also after multiple additions of the sacrificial oxidant. It can be speculated that such active species are small iridium clusters bearing R-functionalized likelyO,O-bidentate ligands

    Effects of Bifidobacterium longum BB536 and Lactobacillus rhamnosus HN001 in IBS patients

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    Background: Irritable bowel syndrome (IBS) is a common gastrointestinal disorder, which still lacks effective therapy. We aimed to investigate the effects of a novel formulation of Bifidobacterium longum BB536 and Lactobacillus rhamnosus HN001 with vitamin B6 (LBB) on symptoms, intestinal permeability, cultivable bacteria and metabolome in IBS subjects. Materials and methods: Twenty-five IBS patients (Rome IV criteria) (M:F = 8:17; age 48 years Â± 11 SD) were randomized to treatment (LBB) or placebo (one month each) in a crossover randomized double-blind controlled trial. Symptoms, intestinal habits, disease severity, intestinal permeability and intestinal microbiota were analysed at 0, 30, 45 and 60 days. Results: Percentage decrease from baseline of abdominal pain (−48.8% vs −3.5%), bloating (−36.35% vs +7.35%) and severity of disease (−30.1% vs −0.4%) was significantly (P <.0001) greater with LBB than placebo, respectively. In IBS-D patients, the improvement from baseline of Bristol score was more consistent with LBB (from 6 Â± 0.4 to 4.3 Â± 1.1, P <.00001) than placebo (from 6.2 Â± 0.7 to 5.3 Â± 1.1, P =.04). In IBS-C patients, Bristol score tended to improve from baseline after LBB (2.6 Â± 1.1 vs 3.2 Â± 0.5, P =.06). LBB significantly improved the percentage of sucralose recovery (colonic permeability) (1.86 Â± 0.1 vs 1.1 Â± 0.2, P =.01). During treatment, presumptive lactic acid bacteria and bifidobacteria, relative abundance of propanoic, butanoic, pentanoic acids and hydrocarbons increased, while phenol decreased. Conclusions: The novel formulation of B. longum BB536 and L. rhamnosus HN001 with B6 vitamin improves symptoms and severity of disease, restores intestinal permeability and gut microbiota in IBS patients

    Seasonal variations of carcass characteristics, meat quality and nutrition value in iberian wild red deer

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    Aim of study: The effects of hunting season (autumn vs. winter) on carcass characteristics and meat quality of Iberian wild red deer were assessed. Area of study: A total of 100 males of wild red deer of Iberian genetic line (Cervus elaphus) were hunted on Ciudad Real (south central Spain). Material and methods: Yields for shoulder (with bone), neck, backbone, loin, tenderloin, leg (with bone), short plate and flank were determined. In addition, samples of Longissimus thoracis et lumborum and Rectus abdominis muscles were collected. Then, pH48, colour measurements, chemical composition, cooking loss, Warner Bratzler shear blade, fatty acid and amino acid profiles and mineral content were analyzed. Main results: Deer hunted in autumn (n=50) had higher (p<0.01) yields of shoulder, backbone and short plate and higher contents of intramuscular fat (IMF), cholesterol and K, Fe and Mn but lower (p<0.001) pH48 and Na, Mg, Zn and Cu contents than deer hunted in winter (n=50). Shear force tended (p=0.05) to be lower for meat collected in autumn than for meat collected in winter. However, loin yield was 59.2% higher (p<0.001) for winter than for autumn carcasses. Deer hunted in winter had higher α-linoleic acid (p<0.05) and long chain n-3 polyunsaturated (p<0.001) percentages than deer hunted in autumn Research highlights: Autumn hunting is recommended to obtain carcasses with higher yields of shoulder, backbone and short plate and meat with higher IMF. Conversely, winter hunting is advisable for higher loin yield and for a profile richer in polyunsaturated fatty acids

    Responses to different feeding levels during the first month post-insemination in highly prolific multiparous sows

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    Aim of study: To evaluate the impact of the feed level during the first month of gestation on body weight evolution, backfat and loin muscle depths and reproductive performances in highly prolific sows.Area of study: Galicia (Northwestern Spain).Material and methods: Thirty-six Danbred sows were assigned to three experimental groups (n=12) receiving, from day 1 to 30 of pregnancy, 2.5, 3.0 or 3.5 kg/d of a standard diet (8.83 MJ net energy and 138.5 g crude protein/kg). In each group, the number of sows in the second-, third- and fourth-cycle was the same. All animals received, of the same diet, 2.5 kg/d from day 31 to 90 and 3.0 kg/d from day 91 to 107. Seven days prior the parturition, sows were moved to the farrowing-lactating facilities where spent until weaning receiving a common standard lactation diet. At 24 h post-farrowing, litters were standardized to 13 piglets each by cross-fostering.Main results: The optimal feeding level during the first 30 days of gestation was 3.0 kg/d because a lower amount penalized their body weight gain and a higher amount did not improve their fatty reserves. It is worth considering that the increase from 2.5 to 3.5 kg/d generated advantages at birth (higher and more homogenous piglet weights) but also handicaps (lower litter size). The effects were similar irrespective of the cycle number.Research highlights: Different feeding levels during the early pregnancy were tested because it is a critical period. Suppling 3.0 kg/d carried out the best productive and reproductive implications

    The CANVAS Mission: Quantifying the Very-Low-Frequency Radio Energy Input from the Ground into the Earth\u27s Magnetosphere

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    Very-low-frequency (VLF) electromagnetic waves, emitted by ground-based sources including lightning and VLF transmitters, can impact the lower ionosphere and magnetosphere through their interaction with the local plasma and energetic particle environments. Quantifying the impacts of these waves requires an accurate assessment of the propagation and attenuation of these waves. The Climatology of Anthropogenic and Natural VLF wave Activity in Space (CANVAS) mission is designed to measure VLF waves in low Earth orbit originating from these ground-based sources. The mission aims to characterize the VLF environment in low Earth orbit to address two main goals: i) constrain the VLF wave injection from the ground into the magnetosphere, and ii) improve models of VLF wave attenuation during propagation through the ionosphere. CANVAS will measure VLF waves using three search coil magnetometers and two electric field dipole antennas that comprise its payload. The search coils are integrated into a 3D-printed Carbon PEEK holder, along with the magnetic field preamplifier board. The search coil system is deployed 1 meter from the spacecraft using a carbon fiber deployable boom, in order to isolate the sensitive search coils from spacecraft noise. The electric field system is composed of four 40 cm monopole antennas, making two orthogonal dipole antennas, integrated into the spacecraft “crown”, along with a custom preamplifier circuit for each monopole. The payload is completed by a custom analog receiver board, providing amplification, anti-alias filtering, and centering for the analog-to-digital converters (ADCs); and a custom digital board, which includes an FPGA for onboard signal processing. Spectral data spanning 0.3–40 kHz are saved at 1-second cadence, providing a continuous “fast survey” data mode for the duration of the mission. The CANVAS spacecraft is a 4U CubeSat, 10 × 10 × 45 cm and under 6 kg. In addition to the 1-meter deployable carbon fiber boom and electric field antennas, the spacecraft incorporates deployable solar panels and a monopole antenna for UHF communications. Data is downlinked in S-band. The spacecraft structure and avionics are custom-designed and built at CU Boulder, while the radios and attitude determination and control system (ADCS) are vendor-supplied components. The CANVAS mission is designed to operate at ∌500 km altitude in a moderate-inclination orbit (∌50 degrees), to ensure global coverage of lightning-generating regions; most lightning globally is confined to within ±50 degrees latitude. Spectra at 1-second cadence account for ∌424 MB of data per day, after housekeeping and encoding overhead. A one-year mission will ensure seasonal coverage to observe the Marshall 1 36th Annual Small Satellite Conference variability in global lightning activity. This paper presents a detailed overview of the CANVAS science goals, payload, spacecraft, and mission. The instrument is now completed and undergoing functional testing and performance characterization, and the spacecraft is beginning integration, expected to be completed in Fall 2022. The CANVAS mission will be ready to launch in early 2023
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