Growth performance, carcass traits and meat quality of growing pigs on different feeding regimes slaughtered at 145\u2009kg BW

This study investigated the effects of feeding regime on growth performance, carcass traits and meat quality of pigs slaughtered at around 145 kg BW. A total of 96 barrows housed in eight pens were allotted to three groups in each pen. One group was fed ad libitum (AL) and the others were fed according to two quasi AL feeding regimes adjusting feed allowances with increasing BW. At slaughterhouse, the weights of the main lean and fat cuts were recorded, and a sample of longissimus lumborum (LL) was taken for physical and chemical analyses. Average daily gain (ADG) approached 940 g d1, and gain to feed ratio (G:F) was close to 0.38. Compared with the AL-feeding regime, the feed restriction reduced the pigs\u2019 ADG (3.5%), feed intake (7.4%) and carcass weight (3%) (p<0.01), but improved their G:F (\ufe4%, p<0.01). Feeding regime did not affect meat quality traits and exerted only minor effects on the weight of primal cuts and on the fatty acid composition of the intramuscular fat of the LL. However, AL-fed pigs tended to yield heavier fat cuts and showed a greater proportion of saturated fatty acid in the LL when compared to restricted feed barrows. In conclusion, moderate restriction in the feeding of medium\u2013heavy pigs seems advisable, as it improves feed efficiency and could cut feed costs compared with the AL-feeding regime without affecting carcass and meat characteristics

Dynamics of a vapor nanobubble collapsing near a solid boundary

In the present paper a diffuse interface approach is used to address the collapse of a sub-micron vapor bubble near solid boundaries. This formulation enables an unprecedented description of interfacial flows that naturally takes into account topology modification and phase changes (both vapor/liquid and vapor/supercritical fluid transformations). Results from numerical simulations are exploited to discuss the complex sequence of events associated with the bubble collapse near a wall, encompassing shock-wave emissions in the liquid and reflections from the wall, their successive interaction with the expanding bubble, the ensuing asymmetry of the bubble and the eventual jetting phase

Impaired coronary blood flow at higher heart rates during atrial fibrillation: investigation via multiscale modelling

Background. Different mechanisms have been proposed to relate atrial fibrillation (AF) and coronary flow impairment, even in absence of relevant coronary artery disease (CAD). However, the underlying hemodynamics remains unclear. Aim of the present work is to computationally explore whether and to what extent ventricular rate during AF affects the coronary perfusion. Methods. AF is simulated at different ventricular rates (50, 70, 90, 110, 130 bpm) through a 0D-1D multiscale validated model, which combines the left heart-arterial tree together with the coronary circulation. Artificially-built RR stochastic extraction mimics the \emph{in vivo} beating features. All the hemodynamic parameters computed are based on the left anterior descending (LAD) artery and account for the waveform, amplitude and perfusion of the coronary blood flow. Results. Alterations of the coronary hemodynamics are found to be associated either to the heart rate increase, which strongly modifies waveform and amplitude of the LAD flow rate, and to the beat-to-beat variability. The latter is overall amplified in the coronary circulation as HR grows, even though the input RR variability is kept constant at all HRs. Conclusions. Higher ventricular rate during AF exerts an overall coronary blood flow impairment and imbalance of the myocardial oxygen supply-demand ratio. The combined increase of heart rate and higher AF-induced hemodynamic variability lead to a coronary perfusion impairment exceeding 90-110 bpm in AF. Moreover, it is found that coronary perfusion pressure (CPP) is no longer a good measure of the myocardial perfusion for HR higher than 90 bpm.Comment: 8 pages, 5 figures, 3 table

Nitrogen and energy partitioning in two genetic groups of pigs fed low-protein diets at 130 kg body weight

The aim was to evaluate the effect of low-protein (LP) or low-amino acid diets on digestibility, energy and nitrogen (N) utilisation in 2 genetic groups (GG) of pigs (129±11 kg BW). Duroc×Large White (A) pigs were chosen to represent a traditional GG for ham production, and Danbred Duroc (D) pigs to represent a GG with fast growing rate and high carcass lean yield. Dietary treatments: a conventional diet (CONV) containing 13.2% CP, and two LP diets, one with LP (10.4%) and low essential AA (LP1), the second with LP (9.7%) and high essential AA (LP2). Compared to CONV, LP2 had the same essential AA content per unit feed, while LP1 the same essential AA content per unit CP. Feed was restricted (DMI=6.8% BW0.75). Four consecutive digestibility/balances periods were conducted with 24 barrows, 12 A and 12 D. Metabolic cages and respiration chambers were used. No significant difference between diets was registered for digestibility. Nitrogen excreted: 41.3, 33.4 and 29.0 g/d (P=0.009), for CONV, LP1 and LP2 diets, respectively. Nitrogen retention was similar between the diets. Heat production (HP) was the lowest for LP diets. There was a tendency (P=0.079) for a lower energy digestibility in D group. The D pigs also had a higher HP and hence a lower retained energy in comparison with the A pigs. In conclusion: it is possible to reduce N excretion using very LP diets and LP-low AA diets; Danbred GG have a higher heat production and a lower energy retention than A pigs

The use of Artificial Neural Networks for extending road traffic monitoring data spatially: an application to the neighbourhoods of Benevento

Abstract In this paper, the use of Artificial Neural Networks (ANNs) for spatially extending road traffic monitoring data is studied. The problem consists of estimating the traffic flows on some links of an urban road network knowing the corresponding data on some other links of the network (monitored links). In a previous paper, the authors studied this problem referring to a whole city obtaining promising results. Starting from these results, here we test if to limit the number of monitored links and non-monitored links to a neighbourhood of a city improves or not the results. These results are useful in medium and large cities where other parts do not at all influence some parts of the network and each neighbourhood can be studied independently from the others. To obtain these results, we have partitioned the network of Benevento in six neighbourhoods and trained six different ANNs with simulated data. Numerical results show that to limit the area analysis improves the results significantly with respect to consider the whole network

Cardiovascular deconditioning during long-term spaceflight through multiscale modeling

Human spaceflight has been fascinating man for centuries, representing the intangible need to explore the unknown, challenge new frontiers, advance technology and push scientific boundaries further. A key area of importance is cardiovascular deconditioning, that is, the collection of hemodynamic changes - from blood volume shift and reduction to altered cardiac function - induced by sustained presence in microgravity. A thorough grasp of the 0G adjustment point per se is important from a physiological viewpoint and fundamental for astronauts' safety and physical capability on long spaceflights. However, hemodynamic details of cardiovascular deconditioning are incomplete, inconsistent and poorly measured to date; thus a computational approach can be quite valuable. We present a validated 1D-0D multiscale model to study the cardiovascular response to long-term 0G spaceflight in comparison to the 1G supine reference condition. Cardiac work, oxygen consumption and contractility indexes, as well as central mean and pulse pressures were reduced, augmenting the cardiac deconditioning scenario. Exercise tolerance of a spaceflight traveler was found to be comparable to an untrained person with a sedentary lifestyle. At the capillary-venous level significant waveform alterations were observed which can modify the regular perfusion and average nutrient supply at the cellular level. The present study suggests special attention should be paid to future long spaceflights which demand prompt physical capacity at the time of restoration of partial gravity (e.g., Moon/Mars landing). Since spaceflight deconditioning has features similar to accelerated aging understanding deconditioning mechanisms in microgravity are also relevant to the understanding of aging physiology on Earth.Comment: 14 pages, 5 tables, 5 figure

The 2019 European guidelines on pulmonary embolism illustrated with the aid of an exemplary case report

Background The European Society of Cardiology guidelines for the diagnosis and management of acute pulmonary embolism (PE) developed in collaboration with the European Respiratory Society (ERS) has been updated in 2019. Recommendations were added or updated on all stages of the evaluation and management of pulmonary embolism, encompassing diagnosis, early treatment, and long-term management. Case summary We illustrate an exemplary case, assembled for the purposes of this review, of a 70-year-old woman who presented at the emergency department with dyspnoea and thoracic pain. She was diagnosed with intermediate-high-risk acute PE and promptly treated with low molecular weight heparin. After 24 h of stay in intensive care unit, she was transferred to the cardiology department and switched to non-vitamin K-dependent oral anticoagulant apixaban 10 mg b.i.d. for 7 days and then 5 mg b.i.d. After discharge from the hospital 8 days later, she received standard-dose apixaban 5 mg b.i.d. for 6 months; the dose was reduced to 2.5 mg b.i.d. for long-term secondary prevention. During follow-up, investigations for PE sequelae were performed due to persisting dyspnoea. Discussion This exemplary case report puts into context the main novel recommendations from the 2019 ESC Guidelines, including the combination of clinical (pre-test) probability and adjusted D-dimer cut-offs for diagnosis of acute PE, the key role of right ventricular dysfunction in risk stratification, the choice and dosage of oral anticoagulant agents in early and extended anticoagulation, and the identification and management of chronic sequelae in the long-term follow-up