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991.
Alexandra C. Green Lena M. Lidfors Sabrina Lomax Livio Favaro Cameron E.F. Clark 《Journal of dairy science》2021,104(1):826-838
Mammalian vocalizations can encode contextual information in both the spectrographic components of their individual vocal units and in their temporal organization. Here we observed 23 Holstein-Friesian dairy cows immediately after birth during interactions with their calf and when their calf was separated to the other side of a fence line. We investigated whether the vocalizations emitted in these postpartum contexts would vary temporally. We also described the maternal and stress behaviors preceding and following postpartum vocal production using kinematic diagrams and characterized call sequence structure. The kinematic diagrams highlight the disruption of maternal responses caused by calf separation and show that behavioral and vocal patterns varied according to the cows' emotional states and proximity to the calf in both contexts. During calf interactions, cows mainly produced closed-mouth calls simultaneous to licking their calf, whereas an escalation of stress responses was observed during calf separation, with the cows approaching the fence line, becoming alert to the calf, and emitting more mixed and open-mouth calls. Call sequences were similarly structured across contexts, mostly containing repetitions of a single call type, with a mean interval of 0.57 s between calls and a greater cumulative vocalization duration, attributed to an increased number of vocal units per sequence. Overall, calf separation was associated with a greater proportion of calls emitted as a sequence (inverse of single isolated calls), a shorter interval between separate call sequences, and a greater number of vocal units per sequence, compared with calf interactions. These temporal vocal features varied predictably with the high stress expression from cows during calf separation and may represent temporal modulations of emotional expression. Despite the noisy farm soundscape, empirical call type and temporal vocal features were easy to measure; thus, findings could be applied to future cattle studies wishing to analyze vocalizations for on-farm welfare assessments. 相似文献
992.
Carla Giovana Luciano Larissa Tessaro Rodrigo Vinicius Lourenço Ana Mônica Quinta Barbosa Bittante Andrezza Maria Fernandes Isabel Cristina Freitas Moraes Paulo José do Amaral Sobral 《International Journal of Food Science & Technology》2021,56(2):587-599
The addition of nisin into a gelatin matrix can change properties of the film. The aim of this work was to develop gelatin-based films containing different nisin concentrations in order to study their influence on the film's antimicrobial and physical properties and their rheological properties as a film-forming solution (FFS). The FFS was characterised by rheological assays, and the gelatin-based active films were characterised and assessed by the effects of nisin concentrations on their various properties, including antimicrobial activity. Nisin's concentration affected not only its viscoelastic properties of FFS but also its film solubility in water, film surface roughness and light barrier. The addition of nisin also slightly modified the water contact angle and the mechanical properties of the gelatin films. Finally, the films demonstrated activity against Staphylococcus aureus and Listeria monocytogenes at concentrations above 56 mg of nisin g−1 of gelatin. 相似文献
993.
994.
M. Staroswiecki A. Moradi Amani 《International Journal of Adaptive Control and Signal Processing》2015,29(6):671-684
Given a fault‐tolerance strategy and a distributed control system, the set of recoverable faults depends on the information pattern that is implemented. This paper shows that fault‐tolerance can be achieved, when possible, by the reconfiguration of the information pattern. A necessary and sufficient recoverability condition is provided, and sub‐optimal solutions are developed for actuator and sensor faults under system reconfiguration. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
995.
996.
V. N. Oparin T. A. Kiryaeva O. M. Usol’tseva P. A. Tsoi V. N. Semenov 《Journal of Mining Science》2015,51(4):641-658
Aiming to build up a phenomenological basis for the theory of interaction between geomechanical, thermal and physicochemical processes in methane-bearing coal in Kuzbass, the authors performed a set of laboratory bench tests on uniaxial stiff loading of various rank coal specimens. The pressure versus temperature dependences are obtained for coal specimens with granite gaskets using high-precision scanning computerized thermal imager. It is shown that temperature changed in coal specimens subjected to loading to failure is connected with volatile content and internal energy relaxation of methane in Kuzbass coal. Using jointly thermal imaging and laser measuring equipment ALMEC-tv for high-precision and detail control of deformation–wave processes in loaded coal specimens by speckle-method, it has for the first time been proved that nonlinear pendulum-type movements of structural elements are possible in coal specimens with varied temperature field, which is of fundamental importance for actualization of previously ignored mass and gas exchange processes in high-stress coal beds of different grade composition under mining, 相似文献
997.
998.
V. N. Oparin V. I. Vostrikov O. M. Usol’tseva P. A. Tsoi V. N. Semenov 《Journal of Mining Science》2015,51(3):624-633
The authors have developed a procedure and a test bench for studying evolution of various nature physical fields in modeling geomedium fracture by fluids. The test bench performs synchronous recording of macro- and micro-deformation, heat and acoustic emission induced in physical models of geomedium under loading to discontinuity. The experimental procedure has been trialed. The analysis of the synchronized test data allows a conclusion on the existence of time–space relationship between different nature physical fields induced during failure of solids. 相似文献
999.
1000.
Fast Measurements of the Gas‐Liquid Diffusion Coefficient in the Gaussian Wake of a Spherical Bubble 下载免费PDF全文
Nicolas Dietrich Jessica Francois Mélanie Jimenez Arnaud Cockx Pascal Guiraud Gilles Hébrard 《化学工程与技术》2015,38(5):941-946
A fast method is proposed for determining the oxygen gas‐liquid diffusion coefficient from measurements of the fluorescence quenching behind a bubble. The approach consists of capturing pictures of the concentration field at micro‐scale in the laminar bubble wake. The Gaussian concentration profiles measured in the wake are demonstrated to be systematically equivalent to an instantaneous plane diffusion case. The approach permits to accurately evaluate the gas‐liquid diffusivity in a very short time of around one second. 相似文献