Effects of Cyclic Heat Stress on the Acute Inflammatory Response in Broilers

Heat stress (HS) is a growing concern in broiler production due to increasing environmental temperatures. Little is known of the overall effect of HS on innate immunity. Lipopolysaccharide (LPS), an outer membrane component of Gram-negative bacteria, is commonly used to study the inflammatory response. In avian species, the local tissue and systemic inflammatory activities in response to LPS may be determined concurrently, over time, in an individual, using the growing feather (GF) pulp dermal test along with blood measurements (dual-window approach). To examine the effect of cyclic HS on the local and systemic acute inflammatory responses, Cobb 500 male broiler chicks were reared under thermoneutral (TN) or cyclic HS conditions. Eight environmental chambers were used, four TN and four HS, with each chamber split into two pens. Beginning at 4 d of age, cyclic HS birds were subjected to 35°C from 8 am to 10 pm and TN temperatures from 10 pm to 8 am. At 37 d of age, four groups of broilers were formed: TN-LPS (n = 8 broilers), TN-PBS (phosphate-buffered saline (vehicle) control; n = 4), HS-LPS (n = 8) and HS-PBS (n = 4). The pulps of 12 GF per broiler were each intradermally (i.d). injected with 10 μL of LPS (100 μg/mL) or 10 μL of PBS. Blood and GF were collected before (0 h) and at 6- and 24-h after GF pulp injection. Blood and GF pulp cell suspensions were immunofluorescently stained and leukocyte population profiles analyzed by flow cytometry. Blood also was used to prepare Wright-stained blood smears for differential leukocyte counts. Data were analyzed by ANOVA (P ≤ 0.05) and Fisher’s multiple means comparison tests to determine differences (P ≤ 0.05) between means. Locally, HS-LPS broilers exhibited lower levels (% pulp cells) of GF pulp infiltrating heterophils at 6- and 24-h, and lower macrophage levels at 24-h post-injection, compared to TN-LPS birds. In the blood, TN and HS broilers had similar baseline line (0 h) concentrations (cells/μL) of heterophils, monocytes, eosinophils, and basophils, but HS broilers had lower (P ≤ 0.05) total WBC and T- and B-lymphocyte levels. Concentrations of circulating heterophils and monocytes were greatly elevated (P ≤ 0.05) at 6- and 24-h, respectively, only in TN-LPS broilers, although a minimal increase (P = 0.091) in heterophils also was observed in HS-LPS broilers at 6 h. By 24 h, blood heterophils returned to pre-injection levels in both HS-LPS and TN-LPS broilers. Overall, results indicated that cyclic HS reduced both the local and systemic acute inflammatory response to LPS in broilers, likely impairing their innate defense against microbial infection. With growing concern regarding HS in the poultry industry, further research should be pursued to elucidate the mechanisms by which HS affects the innate immune system of broilers. Application of this approach may be utilized to select individuals expressing greater innate immune robustness while experiencing HS

Effects of Cyclic Heat Stress on the Acute Inflammatory Response in Broilers

Heat stress (HS) is a growing concern in broiler production due to increasing environmental temperatures. Little is known of the overall effect of HS on innate immunity. Lipopolysaccharide (LPS), an outer membrane component of Gram-negative bacteria, is commonly used to study the inflammatory response. In avian species, the local tissue and systemic inflammatory activities in response to LPS may be determined concurrently, over time, in an individual, using the growing feather (GF) pulp dermal test along with blood measurements (dual-window approach). To examine the effect of cyclic HS on the local and systemic acute inflammatory responses, Cobb 500 male broiler chicks were reared under thermoneutral (TN) or cyclic HS conditions. Eight environmental chambers were used, four TN and four HS, with each chamber split into two pens. Beginning at 4 d of age, cyclic HS birds were subjected to 35°C from 8 am to 10 pm and TN temperatures from 10 pm to 8 am. At 37 d of age, four groups of broilers were formed: TN-LPS (n = 8 broilers), TN-PBS (phosphate-buffered saline (vehicle) control; n = 4), HS-LPS (n = 8) and HS-PBS (n = 4). The pulps of 12 GF per broiler were each intradermally (i.d). injected with 10 μL of LPS (100 μg/mL) or 10 μL of PBS. Blood and GF were collected before (0 h) and at 6- and 24-h after GF pulp injection. Blood and GF pulp cell suspensions were immunofluorescently stained and leukocyte population profiles analyzed by flow cytometry. Blood also was used to prepare Wright-stained blood smears for differential leukocyte counts. Data were analyzed by ANOVA (P ≤ 0.05) and Fisher’s multiple means comparison tests to determine differences (P ≤ 0.05) between means. Locally, HS-LPS broilers exhibited lower levels (% pulp cells) of GF pulp infiltrating heterophils at 6- and 24-h, and lower macrophage levels at 24-h post-injection, compared to TN-LPS birds. In the blood, TN and HS broilers had similar baseline line (0 h) concentrations (cells/μL) of heterophils, monocytes, eosinophils, and basophils, but HS broilers had lower (P ≤ 0.05) total WBC and T- and B-lymphocyte levels. Concentrations of circulating heterophils and monocytes were greatly elevated (P ≤ 0.05) at 6- and 24-h, respectively, only in TN-LPS broilers, although a minimal increase (P = 0.091) in heterophils also was observed in HS-LPS broilers at 6 h. By 24 h, blood heterophils returned to pre-injection levels in both HS-LPS and TN-LPS broilers. Overall, results indicated that cyclic HS reduced both the local and systemic acute inflammatory response to LPS in broilers, likely impairing their innate defense against microbial infection. With growing concern regarding HS in the poultry industry, further research should be pursued to elucidate the mechanisms by which HS affects the innate immune system of broilers. Application of this approach may be utilized to select individuals expressing greater innate immune robustness while experiencing HS

Observing without acting: a balance of excitation and suppression in the human corticospinal pathway

Transcranial magnetic stimulation (TMS) studies of human primary motor cortex (M1) indicate an increase corticospinal excitability during the observation of another's action. This appears to be somewhat at odds with recordings of pyramidal tract neurons in primate M1 showing that there is a balance of increased and decreased activity across the population. TMS is known to recruit a mixed population of cortical neurons, and so one explanation for previous results is that TMS tends to recruit those excitatory output neurons whose activity is increased during action observation. Here we took advantage of the directional sensitivity of TMS to recruit different subsets of M1 neurons and probed whether they responded differentially to action observation in a manner consistent with the balanced change in activity in primates. At the group level we did not observe the expected increase in corticospinal excitability for either TMS current direction during the observation of a precision grip movement. Instead, we observed substantial inter-individual variability ranging from strong facilitation to strong suppression of corticospinal excitability that was similar across both current directions. Thus, we found no evidence of any differential changes in the excitability of distinct M1 neuronal populations during action observation. The most notable change in corticospinal excitability at the group level was a general increase, across muscles and current directions, when participants went from a baseline state outside the task to a baseline state within the actual observation task. We attribute this to arousal- or attention-related processes, which appear to have a similar effect on the different corticospinal pathways targeted by different TMS current directions. Finally, this rather non-specific increase in corticospinal excitability suggests care should be taken when selecting a "baseline" state against which to compare changes during action observation

Frequency-dependent modulation of cerebellar excitability during the application of non-invasive alternating current stimulation

Background: it is well-known that the cerebellum is critical for the integrity of motor and cognitive actions. Applying non-invasive brain stimulation techniques over this region results in neurophysiological and behavioural changes, which have been associated with the modulation of cerebellar-cerebral cortex connectivity. Here, we investigated whether online application of cerebellar transcranial alternating current stimulation (tACS) results in changes to this pathway. Methods: thirteen healthy individuals participated in two sessions of cerebellar tACS delivered at different frequencies (5Hz and 50Hz). We used transcranial magnetic stimulation to measure cerebellar-motor cortex (M1) inhibition (CBI), short-intracortical inhibition (SICI) and short-afferent inhibition (SAI) before, during and after the application of tACS. Results: we found that CBI was specifically strengthened during the application of 5Hz cerebellar tACS. No changes were detected immediately following the application of 5Hz stimulation, nor at any time point with 50Hz stimulation. We also found no changes to M1 intracortical circuits (i.e. SICI) or sensorimotor interaction (i.e. SAI), indicating that the effects of 5Hz tACS over the cerebellum are site-specific. Conclusions: cerebellar tACS can modulate cerebellar excitability in a time- and frequency-dependent manner. Additionally, cerebellar tACS does not appear to induce any long-lasting effects (i.e. plasticity), suggesting that stimulation enhances oscillations within the cerebellum only throughout the stimulation period. As such, cerebellar tACS may have significant implications for diseases manifesting with abnormal cerebellar oscillatory activity and also for future behavioural studies

Premovement suppression of corticospinal excitability may be a necessary part of movement preparation

In a warned reaction time (RT) task, corticospinal excitability (CSE) decreases in task-related muscles at the time of the imperative signal (preparatory inhibition). Because RT tasks emphasise speed of response, it is impossible to distinguish whether preparatory inhibition reflects a mechanism preventing premature reactions, or whether it is an inherent part of movement preparation. We used transcranial magnetic stimulation (TMS) to study CSE changes preceding RT movements and movements that were either self-paced (SP) or performed at predictable times to coincide with an external event (PT). Results show that CSE changes over a similar temporal profile in all cases, suggesting that preparatory inhibition is a necessary state in planned movements allowing the transition between rest and movement. Additionally, TMS given shortly before the times to move speeded the onset of movements in both RT and SP contexts, suggesting that their initiation depends on a form of trigger that can be conditioned by external signals. On the contrary, PT movements do not show this effect, suggesting the use of a mechanistically different triggering strategy. This relative immunity of PT tasks to be biased by external events may reflect a mechanism that ensures priority of internal predictive signals to trigger movement onset

Border Carbon Adjustments Based on Avoided Emissions: Addressing the Challenge of Its Design

Carbon pricing is an essential instrument to address climate change. However international differences in carbon control policies may cause not only carbon leakage but also competitiveness disadvantages. In this context, border carbon adjustments are a promising tool for discouraging these problems. But designing a real-world border carbon adjustment instrument implies to consider significant issues: technical feasibility, data availability, the risk of retaliation from developing countries, and its compatibility within the World Trade Organization legal framework. There are still no conclusive answers about a proper design. This paper is an attempt to address the above-mentioned challenges proposing a carbon border tax (CBT) based on avoided emissions. Such a CBT is applied at a product level and not at a sector level, and all international prices are deflated to guarantee that import like goods received a treatment similar to like domestic products. Using the WIOD, we simulate a CBT based on avoided emissions applied by the European Union, and we compare the results with a CBT based on embodied emissions. (c) 2017This work was supported by the Spanish Ministry of Economy and Competitiveness [grant numbers ECO2015-67524-R , ECO2015-68023 , and HAR2015-69620-C2-1-P ]; and the AGAUR of Catalonia's Government [grant number 2014SGR-950 ]

Sensitivity of the spherical gravitational wave detector MiniGRAIL operating at 5 K

We present the performances and the strain sensitivity of the first spherical gravitational wave detector equipped with a capacitive transducer and read out by a low noise two-stage SQUID amplifier and operated at a temperature of 5 K. We characterized the detector performance in terms of thermal and electrical noise in the system output sygnal. We measured a peak strain sensitivity of $1.5\cdot 10^{-20} Hz^{-1/2}$ at 2942.9 Hz. A strain sensitivity of better than $5\cdot 10{-20}Hz{-1/2}$ has been obtained over a bandwidth of 30 Hz. We expect an improvement of more than one order of magnitude when the detector will operate at 50 mK. Our results represent the first step towards the development of an ultracryogenic omnidirectional detector sensitive to gravitational radiation in the 3kHz range.Comment: 8 pages, 5 figures, submitted to Physical Review

Tremor in motor neuron disease may be central rather than peripheral in origin

BACKGROUND AND PURPOSE: Motor neuron disease (MND) refers to a spectrum of degenerative diseases affecting motor neurons. Recent clinical and post-mortem observations have revealed considerable variability in the phenotype. Rhythmic involuntary oscillations of the hands during action, resembling tremor, can occur in MND, but their pathophysiology has not yet been investigated. METHODS: A total of 120 consecutive patients with MND were screened for tremor. Twelve patients with action tremor and no other movement disorders were found. Ten took part in the study. Tremor was recorded bilaterally using surface electromyography (EMG) and triaxial accelerometer, with and without a variable weight load. Power spectra of rectified EMG and accelerometric signal were calculated. To investigate a possible cerebellar involvement, eyeblink classic conditioning was performed in five patients. RESULTS: Action tremor was present in about 10% of our population. All patients showed distal postural tremor of low amplitude and constant frequency, bilateral with a small degree of asymmetry. Two also showed simple kinetic tremor. A peak at the EMG and accelerometric recordings ranging from 4 to 12 Hz was found in all patients. Loading did not change peak frequency in either the electromyographic or accelerometric power spectra. Compared with healthy volunteers, patients had a smaller number of conditioned responses during eyeblink classic conditioning. CONCLUSIONS: Our data suggest that patients with MND can present with action tremor of a central origin, possibly due to a cerebellar dysfunction. This evidence supports the novel idea of MND as a multisystem neurodegenerative disease and that action tremor can be part of this condition

Density correlations in ultracold atomic Fermi gases

We investigate density fluctuations in a coherent ensemble of interacting fermionic atoms. Adapting the concept of full counting statistics, well-known from quantum optics and mesoscopic electron transport, we study second-order as well as higher-order correlators of density fluctuations. Using the mean-field BCS state to describe the whole interval between the BCS limit and the BEC limit, we obtain an exact expression for the cumulant-generating function of the density fluctuations of an atomic cloud. In the two-dimensional case, we obtain a closed analytical expression. Poissonian fluctuations of a molecular condensate on the BEC side are strongly suppressed on the BCS side. The size of the fluctuations in the BCS limit is a direct measure of the pairing potential. We also discuss the BEC-BCS crossover of the third cumulant and the temperature dependence of the second cumulant.Comment: 4 pages, 4 figures. To appear in Phys. Rev. A. New calculation of the bin statistics of a free Bose gas; updated and extended bibliograph

Ropinirole, a dopamine agonist with high D3 affinity, reduces proactive inhibition: A double-blind, placebo-controlled study in healthy adults

Response inhibition describes the cognitive processes mediating the suppression of unwanted actions. A network involving the basal ganglia mediates two forms of response inhibition: reactive and proactive inhibition. Reactive inhibition serves to abruptly stop motor activity, whereas proactive inhibition is goal-orientated and results in slowing of motor activity in anticipation of stopping. Due to its impairment in several psychiatric disorders, the neurochemistry of response inhibition has become of recent interest. Dopamine has been posed as a candidate mediator of response inhibition due to its role in functioning of the basal ganglia and the observation that patients with Parkinson's disease on dopamine agonists develop impulse control disorders. Although the effects of dopamine on reactive inhibition have been studied, substantial literature on the role of dopamine on proactive inhibition is lacking. To fill this gap, we devised a double-blind, placebo-controlled study of 1 mg ropinirole (a dopamine agonist) on response inhibition in healthy volunteers. We found that whilst reactive inhibition was unchanged, proactive inhibition was impaired when participants were on ropinirole relative to when on placebo. To investigate how ropinirole mediated this effect on proactive inhibition, we used hierarchical drift-diffusion modelling. We found that ropinirole impaired the ability to raise the decision threshold when proactive inhibition was called upon. Our results provide novel evidence that an acute dose of ropinirole selectively reduces proactive inhibition in healthy participants. These results may help explain how ropinirole induces impulse control disorders in susceptible patients with Parkinson's disease