815 research outputs found
Assembly of the Auditory Circuitry by a Hox Genetic Network in the Mouse Brainstem
Rhombomeres (r) contribute to brainstem auditory nuclei during development. Hox genes are determinants of rhombomere-derived fate and neuronal connectivity. Little is known about the contribution of individual rhombomeres and their associated Hox codes to auditory sensorimotor circuitry. Here, we show that r4 contributes to functionally linked sensory and motor components, including the ventral nucleus of lateral lemniscus, posterior ventral cochlear nuclei (VCN), and motor olivocochlear neurons. Assembly of the r4-derived auditory components is involved in sound perception and depends on regulatory interactions between Hoxb1 and Hoxb2. Indeed, in Hoxb1 and Hoxb2 mutant mice the transmission of low-level auditory stimuli is lost, resulting in hearing impairments. On the other hand, Hoxa2 regulates the Rig1 axon guidance receptor and controls contralateral projections from the anterior VCN to the medial nucleus of the trapezoid body, a circuit involved in sound localization. Thus, individual rhombomeres and their associated Hox codes control the assembly of distinct functionally segregated sub-circuits in the developing auditory brainstem
Aeroacoustics of sawtooth trailing-edge serrations under aerodynamic loading
The impact of aerodynamic loading on a serrated trailing edge is studied experimentally. Aerodynamic and acoustic measurements are conducted on a sawtooth-shaped trailing edge, retrofitted to a flat plate featuring a trailing-edge flap, and placed at incidence to the free-stream flow. The turbulent flow across the trailing edge is inspected by time-resolved three-dimensional velocity field measurements obtained from 4D-PIV, while the wall-pressure fluctuations are measured with surface-embedded microphones. Results discuss the relation between the velocity fluctuations over the serrations, the surface pressure fluctuations, and the far-field noise spectra. The aerodynamic analysis discusses the effect of counter-rotating vortex pairs, generated by the pressure imbalance across the edges of the serrations under loading. It is shown that the interaction of these vortices with the incoming turbulence affects the intensity of the wall-pressure spectrum at the outer rim of the serration surface. On the suction side, the intensity of the pressure fluctuations from the incoming boundary layer dominates over that induced by the vortex pairs. On the pressure side, instead, the velocity gradient prescribed by the vortex pairs produces a significant increase of the pressure fluctuations around the edges. The resulting spatial distribution of the wall-pressure fluctuations directly affects the far-field noise. Scattering predictions carried out with the wall-pressure fluctuations in the centre and root (on the suction side) exhibit good agreement with the measured noise in the low-frequency range, whereas using the surface pressure data at the tip of the serration (on the pressure side) yields a better prediction in the high-frequency range
Cortisol levels of shelter dogs in animal assisted interventions in a prison: An exploratory study
Previous studies regarding the Animal Assisted Interventions (AAI) have mainly focused on the beneficial effects of humanâanimal interactions on human health; whereas the impact of such activities on the welfare of the animals involved has received limited attention. So far, few studies have addressed this issue by evaluating the physiological and behavioral reactions of therapy dogs during the interventions. The aim of this study was to evaluate the potential effect of AAI on the cortisol levels of shelter dogs. Five dogs participated in weekly AAI working activities with adult inmates held at a prison of the South of Italy for two months. Saliva samples were collected every two weeks in three conditions: at the kennel (baseline), after transportation and at the end of the working sessions. The results revealed a significant decrease in the cortisol baseline at the end of the AAI program, suggesting that the activities carried out with humans and in a different environment could improve the welfare of dogs housed in kennels. Moreover, we found that transportation significantly increased subjectsâ cortisol levels, suggesting that it is a critical phase that deserves particular care
Antioxidants in assisted reproductive technologies: An overview on dog, cat, and horse
Assisted reproductive technologies (ARTs) are widely used as a tool to improve reproductive per- formance in both humans and animals. In particular, in the veterinary field, ARTs are used to improve animal genetics, recover endangered animals, and produce offspring in the event of sub- fertility or infertility in males or females. However, the use of ARTs did not improve the fertilization rate in some animals due to various factors such as the difficulty in reproducing an anatomical and humoral substrate typical of the natural condition or due to the increase in catabolites and their difficult elimination. The in vitro environment allows the production and increase in the concentration of substances, including reactive oxygen species (ROS), which could be harmful to gametes. If produced in high concentration, the ROS becomes deleterious, both in vitro and in vivo systems. It has been seen that the use of antioxidants can help neutralize or counteract the production of ROS. The present study aims to report the latest findings regarding the use of antioxidants in ARTs of some domestic species, such as dogs, cats, and horses, compared to other animal species, such as cattle, in which ARTs have instead developed more widely
Human-animal relationship dysfunction: A case study of animal hoarding in italy
âAnimal hoardingâ or âcompulsive hoarding of animalsâ is a psychiatric disease, which has important social implications and a profound influence on animal welfare. To date, this phenomenon has been little investigated and largely unexplored. The present study aims to systematically describe a case of animal hoarding, which remains unresolved. The report refers to a case of a woman suffering from animal hoarding that emerged in 2005. From March 2014 to December 2019, 450 animals were seized over nine different occasions. This disease had significant implications on the welfare of the animals collected, which lived in poor housing and hygiene conditions that frequently led to their death. Since animal hoarding cases involve sanitary, legal, and veterinary aspects, we believe that a multidisciplinary approach is necessary in order to prevent a recurrence and a new accumulation of animals. A holistic approach should be taken according to the One Health principle that involves different stakeholders at every level in order to adopt an efficient solution
âWrites a fair hand and appears to be well qualifiedâ : the recruitment of Bank of England clerks, 1800-1815
This is an Open Access article, distributed under the terms of the Creative Commons Attribution licence (http://creativecommons.org/licenses/by/3.0/), which permits unrestricted re-use, distribution, and reproduction in any medium, provided the original work is properly citedThe financial strains of the Revolutionary and Napoleonic Wars had a significant impact on the Bank of England. In its position as banker to the state and manager of the stateâs debt, it experienced a significant increase in workload and thus was forced rapidly to expand its workforce. From a complement of around 300 in the mid-1780s, the number of clerks employed had increased to over 900 in 1815. Using a unique set of records preserved in the Bankâs archives, this article investigates the backgrounds and skills of the men recruited during the expansion of the early nineteenth century. It finds a significant gap between the skills required by the Bank and the skills possessed by its potential workforce.Peer reviewedFinal Published versio
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