Anticonstriction Effect of MCA in Rats by Danggui Buxue Decoction

Objective: Danggui Buxue decoction (DBD), consisting of Angelicae Sinensis Radix (ASR) and Astragali Radix (AR), is a famous prescription with the function of antivasoconstriction. This study intends to probe its mechanisms on the relaxation of the middle cerebral artery (MCA).Methods: Vascular tension of rat MCA was measured using a DMT620 M system. First, the identical series of concentrations of DBD, ASR, and AR were added into resting KCl and U46619 preconstricted MCA. According to the compatibility ratio, their dilatation effects were further investigated on KCl and U46619 preconstricted vessels. Third, four K+ channel blockers were employed to probe the vasodilator mechanism on KCl-contracted MCA. We finally examined the effects of DBD, ASR, and AR on the vascular tone of U46619-contracted MCA in the presence or absence of Ca2+.Results: Data suggested that DBD, ASR, and AR can relax on KCl and U46619 precontracted MCA with no effects on resting vessels. The vasodilator effect of ASR was greater than those of DBD and AR on KCl-contracted MCA. For U46619-contracted MCA, ASR showed a stronger vasodilator effect than DBD and AR at low concentrations, but DBD was stronger than ASR at high concentrations. Amazingly, the vasodilator effect of DBD was stronger than that of AR at all concentrations on two vasoconstrictors which evoked MCA. The vasodilator effect of ASR was superior to that of DBD at a compatibility ratio on KCl-contracted MCA at low concentrations, while being inferior to DBD at high concentrations. However, DBD exceeded AR in vasodilating MCA at all concentrations. For U46619-constricted MCA, DBD, ASR, and AR had almost identical vasodilation. The dilation of DBD and AR on KCl-contracted MCA was independent of K+ channel blockers. However, ASR may inhibit the K+ channel opening partially through synergistic interactions with Gli and BaCl2. DBD, ASR, and AR may be responsible for inhibiting [Ca2+]out, while ASR and AR can also inhibit [Ca2+]in.Conclusion: DBD can relax MCA with no effects on resting vessels. The mechanism may be related to ASR’s inhibition of KATP and Kir channels. Meanwhile, the inhibition of [Ca2+]out by DBD, ASR, and AR as well as the inhibition of [Ca2+]in by ASR and AR may contribute to dilate MCA.

Speed versus damage: using selective feedback to modulate laparoscopic simulator performance

Background Adaptive training is an approach in which training variables change with the needs and traits of individual trainees. It has potential to mitigate the effect of personality traits such as impulsiveness on surgical performance. Selective performance feedback is one way to implement adaptive training. This paper investigates whether selective feedback can direct performance of trainees of either high- or low impulsiveness. Methods A total of 83 inexperienced medical students of known impulsiveness performed a four-session laparoscopic training course on a Virtual Reality Simulator. They performed two identical series of tasks every session. During one series of tasks they received performance feedback on duration and during the other series they received feedback on damage. Performance parameters (duration and damage) were compared between the two series of tasks to assess whether selective performance feedback can be used to steer emphasis in performance. To assess the effectiveness of selective feedback for people of high- or low impulsiveness, the difference in performance between the two series for both duration and damage was also assessed. Results Participants were faster when given performance feedback for speed for all exercises in all sessions (average z-value = − 4.14, all p values < .05). Also, they performed better on damage control when given performance feedback for damage in all tasks and during all sessions except for one (average z-value = − 4.19, all but one p value < .05). Impulsiveness did not impact the effectiveness of selective feedback. Conclusion Selective feedback on either duration or damage can be used to improve performance for the variable that the trainee receives feedback on. Trainee impulsiveness did not modulate this effect. Selective feedback can be used to steer training focus in adaptive training systems and can mitigate the negative effects of impulsiveness on damage control.

All-inorganic perovskite quantum dot light-emitting memories

Field-induced ionic motions in all-inorganic CsPbBr3 perovskite quantum dots (QDs) strongly dictate not only their electro-optical characteristics but also the ultimate device performance of the CsPbBr3 optoelectronics. Novel device concepts with multiple functionalities can as a result be achieved based on CsPbBr3 by carefully controlling the ionic flow under different bias conditions. Here, we show that by manipulating the ion migrations in two nominally identical, series-connected Ag/CsPbBr3/ITO devices, one device can operate as a resistive random-access memory (RRAM) while the other simultaneously as a light-emitting electrochemical cell (LEC), or vice versa, simply through the polarity switching of the external bias across the entire structure. We further show that this electrically switchable, series-connected perovskite memories and light emitters can be employed as a novel all-perovskite light-emitting memory (LEM) device for simultaneous electronic and optical reading of the encoded information in communication and computation applications. We present a physical picture that clearly depicts the movements of each ionic species and their reduction or oxidation processes in the perovskite LEM responsible for the observed electronic and optical characteristics. The demonstrated bifunctionality of the simple metal-perovskite-metal structures and the novel device concept derived from their creative synergy opens up a completely new horizon for more advanced all-inorganic perovskite optoelectronics with novel functionalities.

Conservation and divergence of related neuronal lineages in the Drosophila central brain

Wiring a complex brain requires many neurons with intricate cell specificity, generated by a limited number of neural stem cells. Drosophila central brain lineages are a predetermined series of neurons, born in a specific order. To understand how lineage identity translates to neuron morphology, we mapped 18 Drosophila central brain lineages. While we found large aggregate differences between lineages, we also discovered shared patterns of morphological diversification. Lineage identity plus Notch-mediated sister fate govern primary neuron trajectories, whereas temporal fate diversifies terminal elaborations. Further, morphological neuron types may arise repeatedly, interspersed with other types. Despite the complexity, related lineages produce similar neuron types in comparable temporal patterns. Different stem cells even yield two identical series of dopaminergic neuron types, but with unrelated sister neurons. Together, these phenomena suggest that straightforward rules drive incredible neuronal complexity, and that large changes in morphology can result from relatively simple fating mechanisms.

Understand Cross-Cultural Analysis

Cross-cultural analysis could be a very perplexing field to understand withmany different viewpoints, aims and concepts. The origins of cross-culturalanalysis in the 19th century world of colonialism was strongly grounded inthe concept of cultural evolution, which claimed that all societies progressthrough an identical series of distinct evolutionary stages. The origin of theword culture comes from the Latin verb colere = "tend, guard, cultivate,till". This concept is a human construct rather than a product of nature. Theuse of the English word in the sense of "cultivation through education" isfirst recorded in 1510. The use of the word to mean "the intellectual side ofcivilization" is from 1805; that of "collective customs and achievements of apeople" is from 1867. The term Culture shock was first used in 1940.

Conservation and Divergence of Related Neuronal Lineages in the Drosophila Central Brain

SummaryWiring a complex brain requires enormous cell specificity. This specificity is laid out via a developmental process where neural stem cells produce countless diverse neurons. To help elucidate this process and resolve the considerable dynamic specificity, we need to observe the development of multiple neuronal lineages. Drosophila central brain lineages are predetermined, comprised of a fixed set of neurons born in pairs in a specific order. To reveal specific roles of lineage identity, Notch-dependent sister fate specification, and temporal patterning in morphological diversification, we mapped approximately one quarter of the Drosophila central brain lineages. While we found large aggregate differences, we also discovered similar patterns of morphological specification and diversification. Lineage identity plus Notch state govern primary neuronal trajectories, whereas temporal fates diversify terminal elaborations in target-specific manners. In addition, we identified ‘related’ lineages of analogous neuron types produced in similar temporal patterns. Two stem cells even yield identical series of dopaminergic neuron types, but with completely disparate sister neurons. These phenomena suggest that large changes in morphological diversity can be the consequence of relatively small differences in lineage fating. Taken together, this large-scale lineage mapping study reveals that relatively simple rules drive incredible neuronal complexity.

Anatomy of Teaching Anatomy: Do Prosected Cross Sections Improve Students Understanding of Spatial and Radiological Anatomy?

Introduction. Cadaveric dissections and prosections have traditionally been part of undergraduate medical teaching. Materials and Methods. Hundred and fifty-nine first-year students in the Faculty of Medicine, University of Colombo, were invited to participate in the above study. Students were randomly allocated to two age and gender matched groups. Both groups were exposed to identical series of lectures regarding anatomy of the abdomen and conventional cadaveric prosections of the abdomen. The test group (n=77, 48.4%) was also exposed to cadaveric cross-sectional slices of the abdomen to which the control group (n=82, 51.6%) was blinded. At the end of the teaching session both groups were assessed by using their performance in a timed multiple choice question paper as well as ability to identify structures in abdominal CT films. Results. Scores for spatial and radiological anatomy were significantly higher among the test group when compared with the control group (P<0.05, CI 95%). Majority of the students in both control and test groups agreed that cadaveric cross section may be useful for them to understand spatial and radiological anatomy. Conclusion. Introduction of cadaveric cross-sectional prosections may help students to understand spatial and radiological anatomy better.

Neural Emotion Regulation Circuitry Underlying Anxiolytic Effects of Perceived Control over Pain

Anxiolytic effects of perceived control have been observed across species. In humans, neuroimaging studies have suggested that perceived control and cognitive reappraisal reduce negative affect through similar mechanisms. An important limitation of extant neuroimaging studies of perceived control in terms of directly testing this hypothesis, however, is the use of within-subject designs, which confound participants' affective response to controllable and uncontrollable stress. To compare neural and affective responses when participants were exposed to either uncontrollable or controllable stress, two groups of participants received an identical series of stressors (thermal pain stimuli). One group (“controllable”) was led to believe they had behavioral control over the pain stimuli, whereas another (“uncontrollable”) believed they had no control. Controllable pain was associated with decreased state anxiety, decreased activation in amygdala, and increased activation in nucleus accumbens. In participants who perceived control over the pain, reduced state anxiety was associated with increased functional connectivity between each of these regions and ventral lateral/ventral medial pFC. The location of pFC findings is consistent with regions found to be critical for the anxiolytic effects of perceived control in rodents. Furthermore, interactions observed between pFC and both amygdala and nucleus accumbens are remarkably similar to neural mechanisms of emotion regulation through reappraisal in humans. These results suggest that perceived control reduces negative affect through a general mechanism involved in the cognitive regulation of emotion.

The paschal alleluia in medieval France

The alleluia was the last proper chant of the Mass to be standardized. Through the twelfth century and beyond, different churches assigned different alleluias to the same Masses, and the composition of new alleluia chants flourished throughout the latter Middle Ages. The Masses from Easter to the octave of Pentecost witness this. A collation of ca. 200 manuscripts demonstrates that identical series of chants are to be found only in sources emanating from the same church (or churches in the same city). Most of the alleluia chants from the eleventh century onward have New Testament or non-scriptural texts, as opposed to the psalmic texts of the earlier post-Pentecostal alleluias. The musical style is varied, ranging from the richly melismatic manner traditionally associated with the alleluia to much more modest melodies with few or no large melismas. A number of the latter can be associated with the reforms of Guillaume de Volpiano at Dijon and in Normandy in the years after 1000.