In vivo synaptic transmission in the zebra finch high vocal center and robust nucleus of the arcopallium after different stimulus patterns

BACKGROUND： Electrophysiological studies using brain slices have revealed that the developmental regulation of synaptic plasticity in vocal learning pathway is essential for song learning in zebra finches. Publications reporting in vivo electrophysiological investigation are scarce. Many aspects of neural mechanisms underlying song learning and production still remain uncertain. OBJECTIVE： To observe the efficacy of paired pulses and the effect on synaptic transmission induced by low-frequency stimulations, high-frequency stimulations, and theta-burst stimulations. DESIGN, TIME AND SETTING： A comparative observation. The experiment was conducted from October 2006 to October 2007 in the Neurophysiology Laboratory of South-China Normal University. MATERIALS： Twenty-four adult male zebra finches were supplied by the Department of Animal Experiment of College of Life Sciences, South China Normal University. A SEN-7203 stimulator （NIHON KOHDEN）, as well as a DSJ-731WF microelectrode amplifier and DSJ-F amplifier （provided by South-China Normal University）, were used to stimulate and record, respectively. METHODS： Animals were randomly divided into low-frequency, high-frequency, and theta-burst frequency stimulation groups. After recording evoked potentials, an input-output curve was evaluated. Subsequently, the efficacy of paired pulses with different stimulus intensity （1/3, 1/2, 2/3, or 3/4 of the value that induced the largest synaptic response）, as well as interpulse intervals （50, 75, and 100 ms）, was measured in each group. The test stimulus intensity was set to a level that evoked 1/2 or 1/3 amplitude of the maximum response. MAIN OUTCOME MEASURES： Changes in amplitude, slope, and area of evoked potentials elicited by different stimulus patterns. RESULTS： （1） Efficacy of paired pulses： there was significant paired-pulse facilitation in the high vocal center and robust nucleus of the arcopallium （HVC-RA） synapse. Efficacy decreased when paired-pulse intervals or stimulus intensities were increased. （2） Low-frequency stimulations at 1 Hz had a negligible effect on efficacy of synaptic transmission, while 5 Hz depressed synaptic transmission for only 5 minutes. （3） High-frequency stimulations at 50 Hz or 100 Hz induced synaptic depression that lasted for up to 30 minutes. （4） Theta-burst stimulation depressed synaptic transmission efficiency significantly for about 10 minutes. However, in contrast to low-frequency or high-frequency stimulations, theta-burst stimulations also induced slight potentiation of synaptic transmission for up to 60 minutes following depression phase, although the slope or area did not change. CONCLUSION： Paired pulses induced a remarkable efficacy of paired pulses in the high vocal center and robust nucleus of the arcopallium pathway. Low-frequency, high-frequency, or theta-burst frequency stimulation did not induce long-lasting changes in synaptic transmission.

Estimating energy release performance of oxidizer-activated aluminum fuel particles under ultrafast stimulus

Aluminum(Al) particles are good fuel additives to improve the energy output performances of explosives. Under detonation environment, reaction delay of Al particles plays a key role in the energy release efficiency. Up to date, reaction delay of Al particles is still limited by the efficiency of mass and heat transfer from oxidizers to Al particles. To address this issue, a homogeneous fuel-oxidizer assembly has recently become a promising strategy. In this work, oxidizer-activated Al fuel particles(ALG) were prepared with glycidyl azide polymer(GAP) as the oxidizer. The ALG was in uniform spherical shape and core-shell structure with shell layer of around 5 nm which was observed by scanning electron microscope and transmission electron microscope. The localized nanoscale mid-IR measurement detected the uniform distribution of characteristic absorption bond of GAP in the shell layer which confirmed the homogenous fuel-oxidizer structure of ALG. A thermal gravimetric analysis of ALG at ultrafast heating rate of 1000℃/min under argon atmosphere was conducted. The decomposition of GAP finished much earlier than that of GAP at heating rate of 10℃/min. Under ultrafast high laser fluence, the reaction response of ALG was characterized and compared with that of micro-sized Al(μAl). With the increase of laser energy, the propagation distance of the shock wave increased. However, the velocity histories were nearly the same when energies were lower than 299 mJ or higher than 706 mJ. The propagation distance of the shock wave for ALG was 0.5 mm larger than that for μAl at 2.1 μs. The underwater explosion showed the peak pressure and the shock wave energy of the ALG-based explosive were both higher than those of the μAl-based explosive at 2.5 m. This study shows the feasibility to improve the energy release of Al-based explosives via using the oxidizer-activated Al fuel particles with energetic polymer as the oxidizer.

Effect of Touch stimulus on the Expression of C-fos and TrkA in Spinal Cord Following Chronic Constriction Injury of the Sciatic Nerve in Rats

Summary: To study the mechanism of the innoxious touch-stimulus on the modulation of hyperalgesia and the expression of the C-fos and the nerve growth factor (NGF) receptor-TrkA in the spinal dorsal horn neurons following the chronic constriction injury (CCI) of the sciatic nerve in rats, 60 female Sprague-Dawley rats were randomly divided into sham-operation group and CCI group, with each group being further divided into 3 subgroups on the 7th,14th and 28th day after operation (n=10). The mechanical and the thermal withdrawal threshold were assessed following the touch stiumulation after the CCI, immunohistochemical methods were employed to observe the expression of the C-fos and TrkA in spinal dorsal horn. Our results showed that the hyperalgesia appeared on the 4th day and reached the maximal level on the 14th day after operation. The expression of the C-fos also increased significantly and reached its maximal level on the 14th day after the touch-stimulus. Meanwhile, the TrkA expression was elevated significantly in both groups, as compared with basic data, and the difference was statistically significant (P<0.05). It is concluded that the level of the C-fos expression changed with the paw withdrawal threshold variation and increased markedly following the innoxious touch-stimulus. The expression of the TrkA receptors also increased gradually following the development of the neuropathic pain. The results suggest that C-fos may play a crucial role in the development of the hyperalgesia in the earlier-time of the neuropathic pain, but TrkA receptors may be involved in the long-lasting adaptive changes of the central pathway in neuropathic pain.

Stability of N-LTNR exposing to severe thermal stimulus

The thermal stability of normal lead styphnate（ N-LTNR） has been studied under severe temperature（- 70 ℃- 130 ℃ for 5 days） with a high optical microscope and camera were used to observe apparent morphology and thermal gravimetric analysis was applied to study the physical changes. In addition,vacuum stability analysis,differential scanning calorimetry（ DSC）,thermal gravimetric analysis（ TGA） and purity analysis were utilized to study the chemical changes. As well as flame sensitivity analysis were used to investigated the explosive changes. The results show that N-LTNR has good chemical stability and fire function stability between- 70 ℃ and 130 ℃,but poor physical stability. When the temperature was exceeded than 110 ℃,the N-LTNR lost crystal water which made the energetic material become darker in color,lager in volume and lighter in weight（ 3. 416%） when the temperature was below- 40 ℃,the phenomenon of crystal broking and jumping happened.

Ultrafast Infrared Spectroscopic Study of Microscopic Structural Dynamics in pH Stimulus-Responsive Hydrogels

Hydrogels show versatile properties and are of great interest in the fields of bioelectronics and tissue engineering.Understanding the dynamics of the water molecules trapped in the three-dimensional polymeric networks of the hydrogels is crucial to elucidate their mechanical and swelling properties at the molecular level.In this report,the poly(DMAEMA-co-AA)hydrogels were synthesized and characterized by the macroscopic swelling measurements under different pH conditions.Furthermore,the microscopic structural dynamics of pH stimulus-responsive hydrogels were studied using FTIR and ultrafast IR spectroscopies from the viewpoint of the SCN-anionic solute as the local vibrational reporter.Ultrafast IR spectroscopic measurements showed the time constants of the vibrational population decay of SCN-were increased from 14±1 ps to 20±1 ps when the pH of the hydrogels varied from2.0 to 12.0.Rotational anisotropy measurements further revealed that the rotation of SCNanionic probe was restricted by the three-dimensional network formed in the hydrogels and the rotation of SCN-anionic probe cannot decay to zero especially at the pH of 7.0.These results are expected to provide a molecular-level understanding of the microscopic structure of the cross-linked polymeric network in the pH stimulus-responsive hydrogels.

Exogenous Protein as an Environmental Stimulus of Biofilm Formation in Select Bacterial Strains

A screening of environmental conditions that would elicit robust biofilm in a collection of Serratia marcescens isolated from soil revealed that exogenous milk protein increased biofilm productivity up to ten-fold. A select screening of fish pathogens, freshwater and human isolates identified several other species that responded similarly to exogenous protein. The optimal protein concentration was species specific;S. marcescens at 5% milk protein, Aeromonas sp. at 2% - 3%, Flavobacterium columnare at 1% and Pseudomonas aeruginosa at 0.1% - 0.4%. Media supplemented with milk protein also increased the cell counts in biofilm as well as the protein incorporated into the biofilm matrix. These data suggest that relatively high concentrations of exogenous protein may serve as an environmental trigger for biofilm formation, particularly for pathogenic bacteria exposed to relatively high concentrations of protein in bodily fluids and mucosal surfaces.

Feather Vibration as a Stimulus for Sensing Incipient Separation in Falcon Diving Flight

Based on our preceding studies on the aerodynamics of a falcoperegrinus in diving flight along a vertical dam it is known that even when the body shape of the bird is rather streamlined in V-shape some feathers tips may elevate in certain regions of the body. These regions were identified in wind tunnel tests for typical diving flight conditions as regions of locally separated flow. A life-size model in V-shape of a falcoperegrinus with artificial feathers fixed along the body was studied in a wind tunnel to focus on the fluid-structure interaction of feathers located in this sector. The distal ends of the feathers show flow-induced vibrations at typical flight conditions which grow linear in amplitude with increasing angle of incidence until incipient separation. In light of the proven existence of vibration-sensitive mechanoreceptors in the follicles of secondary feathers in birds it is hypothesized that this linear amplitude response offers the bird to sense the angle of incidence during the diving flight using the vibration magnitude as sensory stimulus. Thus the bird in streamlined shape has still a good measure to control its attitude to be in the narrow window of safe angle of incidence. This might have implications also for other birds or technical applications of airfoil sensors regarding incipient separation detection.

MEASUREMENT OF AMPLITUDE AND DELAY OF STIMULUS FREQUENCY OTOACOUSTIC EMISSIONS

Although stimulus frequency otoacoustic emissions (SFOAEs) have been used as a non-invasive measure of cochlear mechanics, clinical and experimental application of SFOAEs has been limited by difficulties in accurately deriving quantitative information from sound pressure measured in the ear canal. In this study, a novel signal processing method for multicomponent analysis (MCA) was used to measure the amplitude and delay of the SFOAE. This report shows the delay-frequency distribution of the SFOAE measured from the human ear. A low level acoustical suppressor near the probe tone significantly suppressed the SFOAE, strongly indicating that the SFOAE was generated at characteristic frequency locations. Information derived from this method may reveal more details of cochlear mechanics in the human ear.

How the Brain Process Stimulus-Response Conflict? New Insights from Lateralized Readiness Potentials Scalp Topography and Reaction Times

Stimulus-Response Compatibility (SRC) refers to the fact that some tasks are performed easier and better than others because of the way stimuli and responses are paired with each other. To assess the brain responses to stimulus-response conflicts, we investigated the behavioral (accuracy and Reaction Times: RTs) as well as the physiological response (Lateralized Readiness Potentials: LRP) modulations in a positional blocked and a conditional mixed design in twelve university students. Results revealed that the performance was less accurate and the RTs, as well as the LRP onset, were delayed under the mixed conditional design. A greater compatibility effect was also noted on accuracy, RTs and LRP onset latency in the mixed design. Consistent with these findings, smaller peak activation at fronto-central areas suggests that more selective inhibition is needed in a mixed design context. Despite a smaller activation, the topographical distribution is similar in both designs. These results indicate that the translation time between stimulus- and response codes are greater under the mixed instruction, while the similar LRP topography suggests that common neural structures underlie LRPs in response to both type of designs.

Who Will Benefit from China’s Stimulus?

Asian exporters are losing another important growth driver, China, as a result of the slowdown in investment in China. Talk of

Whether “Buy American” Could Become “Bye America”——Trade Protection in the Stimulus Package

Congress is working toward swift passage of economic stimulus legislation to jolt the U.S.economy out of a downward spiral.

Stimulus 2009(Part Two)——Measures facilitate light & textile industry

Support SMEs Increase the scale of financial supports at various levels to support SMEs, sustain light & textile projects with promising market prospect, notable driving of employment and remarkable social benefits, and step up investments in construction of credit guarantee system and service

Investment Stimulus

LIMPOPO Province in the far north of South Africa takes its name from the mighty Limpopo River. which forms the natural border with Zimbabwe. It is a region teeming with wildlife, and bountiful historical and cultural treasures, along with spectacular scenery, Now the province, and its northern-most town. Musina. are on the verge of bigger things.

Stimulus 2009--beef up domestic demand

The State Council conducted researches and deployed measures to further expand domestic demand to facilitate steadfast economic growth, as well as nailed down ten measures, which will invest in a total of RMB four trillion Yuan till the end of 2010 to stimulate domestic demand. Following that, the State Council issued six policies and measures to promote sound development of the light industry and other industries, like textile industry. This enables us to see the determination and action of the government in combating the financial storm and developing the social economy. Meanwhile, it is a good news to the textile industry in unfavorable situation, which can be deemed as an unprecedented powerful policy supports. Absolutely, this will bring a opportunity to China's textile industry. Therefore, we pick out items closely interrelated to the textile industry from the "10+6" policy for elaboration, so as to work out how we shall take full advantage of the supports. Wherein, the ten measures to expand domestic demand do not directly target the textile industry, but they will, with the implementation of various policies and investments, surely drive domestic demand to grow, and contribute to the growth of textile industry.

Policy Stimulus Bears Fruit

In the second quarter of 2018, the Chinese economy grew at 6.7 percent which is in line with expectations and marginally slower than the 6.8-percent growth recorded in the previous three quarters. Growth during the first half this year also stands at 6.7 percent. Amidst the ongoing trade war with the United States, as of July 27, the renminbi （RMB） has fallen 8.2 percent against the dollar since April 2. Having fallen below 3,000 in June for the first time in two years.

Comparison of C50 for Propofol-remifentanil Target-controlled Infusion and Bispectral Index at Loss of Consciousness and Response to Painful Stimulus in Elderly and Young Patients

Background：In this prospective randomized study,we compared the predicted blood and effect-site C50 for propofol and remifentanil target-controlled infusion （TCI） and the bispectral index （BIS） values at loss of consciousness （LOC） and response to a standard noxious painful stimulus （LOS） in elderly and young patients,respectively.We hypothesized that the elderly patients will require lower target concentration of both propofol and remifentanil at above two clinical end-points.Methods：There were 80 American Society of Anesthesiologists （ASA） physical status Ⅰ Ⅱ unpremedicated patients enrolled in this study,they were divided into elderly group （age ≥65 years,n =40） and young group （aged 18-54 years,n =40）.Propofol was initially given to a predicted blood concentration of 1.2 μg/ml and thereafter increased by 0.3 μg/ml every 30 s until Observer＇s Assessment of Alertness and Sedation score was 1.The propofol level was kept constant,and remifentanil was given to provide a predict blood concentration of 2.0 ng/ml,and then increased by 0.3 ng/ml every 30 s until loss of response to a tetanic stimulus.BIS （version 3.22,BIS Quattro sensor） was also recorded.Results：In elderly group,the propofol effect-site C50 at LOC of was 1.5 （1.4-1.6） μg/ml,was significantly lower than that of young group,which was 2.2 （2.1-2.3） μg/ml,the remifentanil effect-site C50 at LOS was 3.5 （3.3-3.7） ng/ml in elderly patients,was similar with 3.7 （3.6-3.8） ng/ml in young patients.Fifty percent of patients lost consciousness at a BIS value of 57.3 （56.4-58.1）,was similar with that of young group,which was 55.2 （54.0-56.3）.Conclusion：In elderly patients,the predicted blood and effect-site concentrations of propofol at LOC were lower than that of young patients.At same sedation status,predicted blood and effect-site concentrations of remifentanil required at LOS were similar in elderly and young patients.BIS were not affected by age.Low-propofol/high-opioid may be optional TCI strategy for elderly patients.

Employment Effectiveness of China's Economic Stimulus Package

Using an input--output method, this paper simulates the impacts of the global financial crisis and the decline of exports on China＇s economy and employment. With shrinking external demand, boosting domestic demand becomes crucial for maintaining economic growth and promoting employment. Our simulated results indicate that an investment scenario with employment as a priority can achieve the objective of employment maximization without significantly reducing growth. Public investment should focus on employment, education, health, housing and social security to rebalance China＇s economy so that it can realize sustained and stable economic growth.

A study on the differences of effect on mast cells and serum 5-HT in the acupoint area of "CV 4" of rats by acupuncture stimulus and thermal stimulus

Objective: To observe the influence of acupuncture stimulus and thermal stimulus on the expression of mast cells(MCs) and 5-hydroxytryptamine(5-HT) in local acupoint area of Guanyuan(关元 CV 4) and serum 5-HT in rats.Methods: Thirty-nine male C57 BL/6 rats were randomly divided into blank control group, acupuncture stimulus group and thermal stimulus group, with 13 rats in each group. The rats were stimulated by manual acupuncture at CV 4 for 5 min in acupuncture stimulus group, while those in thermal stimulus group were stimulated by adopting a thermal moxibustion apparatus on CV 4 for 30 min. The expression of MC and 5-HT in the skin in the acupoint area of CV 4 before and after acupuncture stimulus and thermal stimulus was observed and analyzed via adopting toluidine blue staining method and immunofluorescence histochemical method(5 rats were selected from each group), and the 5-HT content in serum before and after stimulus was determined through enzyme-linked immunosorbent assay(ELISA)(8 rats were selected from each group). The influence of acupuncture stimulus and thermal stimulus on the contents of MC and 5-HT in the skin and serum 5-HT in rats was analyzed and compared.Results: ① After acupuncture stimulus or thermal stimulus on CV 4 of C57 BL/6 rats, the number of MC in the acupoint area significantly increased when compared with that in blank group(the acupuncture stimulus group 12.40 ± 2.07 vs. the blank group 3.00 ±5.96;thermal stimulus group 26.20 ± 10.85 vs. the blank group 12.40 ± 2.07, both P< 0.05), and MC aggregation and degranulation were observed(the acupuncture stimulus group 17.80 ±4.55 vs. the blank group 8.00 ±3.16;the thermal stimulus group24.00±9.05 vs. the blank group 8.00±3.16. P<0.05, P< 0.01).② After acupuncture stimulus or thermal stimulus, 5-HT was released by MCs in the acupoint area, which aggregated around the blood vessels,and the number of 5-HT in the acupoint area significantly increased when compared with that in blank group(the blank group 3.00 ±1.28 vs. the acupuncture stimulus group 10.02 ±3.21;the blank group3.00 ±1.28 vs. the thermal stimulus group 14.00 ±3.94, both P< 0.01).③ Compared with blank group,both acupuncture stimulus and thermal stimulus could reduce the 5-HT content in serum(the blank group 0.72 ±0.2372 vs. acupuncture stimulus group 0.43 ±0.21: the blank group 0.72 ±0.24 vs. thermal stimulus group 0.32 ±0.18, both P<0.01), and the effect in thermal stimulus group was slightly superior to that in acupuncture stimulus group(P<0.05).Conclusion: Both acupuncture stimulus and thermal stimulus can cause the aggregation and degranulation of MCs and high expression of 5-HT in the acupoint area. The effect of thermal stimulus was superior to that of acupuncture stimulus in degranulation.

Localizing epileptic focus and assessing electrical stimulus effects on epilepsy in rats using stretchable micro electrocorticogram electrodes

Epilepsy is a chronic nervous disease with increasing incidence worldwide,while the accurate localization of epileptic focus and the corresponding treatment are still challenging due to the lack of effective tools to monitor and modulate the related brain neurological activities.In this work,stretchable micro electrocorticogram(mECoG)electrodes are developed and used to investigate penicillininduced epilepsy in rats.The electrodes possess excellent stretchability,conformality,anti-interference ability and sufficient resolution to successfully monitor electroencephalogram(EEG)signals,which is superior to traditional rigid polyimide-based electrodes.Characteristic epileptic spike waves are detected and analyzed to study the epileptic focus and electrical stimulus effects during epileptic seizures.It is found that the spike waves occur first in the visual cortex which is likely to be the epileptic focus.Epileptic spike wave frequency quickly increases to 1.07 Hz where it reaches a plateau and remains stable.There is no dominant brain hemisphere that would show early warning of epileptic seizures.Electrical stimuli for various times are applied after administering penicillin.It is found that 15 min of electrical stimulus has the best restraining effect on epileptic seizures.The mECoG electrodes developed in this study show potentials for applications in stretchable biomedical devices.

Crisis, Stimulus Package and Migration in China

This paper analyzes the short-term and long-term effects that the global economic crisis and the investment priorities of the Chinese Government＇s stimulus package had on Chinese migrant flows between 2008 and 2014. Combining micro-level household survey data and macro-level statistics, the authors have found that in the short run, the regional and sectoral impact of the crisis, combined with the government＇s investment priorities, caused a reorientation of migration routes from the export-oriented coastal provinces towards the central and western regions, from inter-provincial migration towards intra-provincial migration, and from manufacturing industry towards the construction sector. However, in the longer run, the decreasing attractiveness of the eastern region and the increasing attractiveness of the western region proved to be transitory, although the pre-crisis relative advantage of the eastern region was not fuUy restored. What proved to be persistent were the attractiveness of the central region and the intra-provincial migration in all three regions, and, in particular, the steady growth of migrants in the construction sector.