Zobrazení zdroje stránky Holbrookthornton1871

The Kibble-Zurek mechanism provides a unified theory to describe the universal scaling laws in the dynamics when a system is driven through a second-order quantum phase transition. However, for first-order quantum phase transitions, the Kibble-Zurek mechanism is usually not applicable. Here, we experimentally demonstrate and theoretically analyze a power-law scaling in the dynamics of a spin-1 condensate across a first-order quantum phase transition when a system is slowly driven from a polar phase to an antiferromagnetic phase. We show that this power-law scaling can be described by a generalized Kibble-Zurek mechanism. Furthermore, by experimentally measuring the spin population, we show the power-law scaling of the temporal onset of spin excitations with respect to the quench rate, which agrees well with our numerical simulation results. Our results open the door for further exploring the generalized Kibble-Zurek mechanism to understand the dynamics across first-order quantum phase transitions.To increase fitness, animals use both internal and external states to coordinate reproductive behaviors. The molecular mechanisms underlying this coordination remain unknown. Here, we focused on pheromone-sensing Drosophila Or47b neurons, which exhibit age- and social experience-dependent increase in pheromone responses and courtship advantage in males. FruitlessM (FruM), a master regulator of male courtship behaviors, drives the effects of social experience and age on Or47b neuron responses and function. We show that simultaneous exposure to social experience and age-specific juvenile hormone (JH) induces chromatin-based reprogramming of fruM expression in Or47b neurons. [https://www.selleckchem.com/products/yo-01027.html DBZ inhibitor] Group housing and JH signaling increase fruM expression in Or47b neurons and active chromatin marks at fruM promoter. Conversely, social isolation or loss of JH signaling decreases fruM expression and increases repressive marks around fruM promoter. Our results suggest that fruM promoter integrates coincident hormone and pheromone signals driving chromatin-based changes in expression and ultimately neuronal and behavioral plasticity.Increasing occurrence of moderate to severe intrauterine adhesion (IUA) is seriously affecting the quality of human life. The aim of the study was to establish IUA models in nonhuman primates and to explore the dual repair effects of human umbilical cord-derived mesenchymal stem cells (huMSCs) loaded on autocrosslinked hyaluronic acid gel (HA-GEL) on endometrial damage and adhesion. Here, we recorded the menstrual cycle data in detail with uterine cavities observed and endometrial tissues detected after intervention, and the thicker endometria, decreased amount of fibrotic formation, increased number of endometrium glands, etc., suggested that both HA-GEL and huMSC/HA-GEL complexes could partially repair IUA caused by mechanical injury, but huMSC/HA-GEL complex transplantation had notable dual repair effects a reliable antiadhesion property and the promotion of endometrial regeneration.Safety concerns about organic media-based batteries are the key public arguments against their widespread usage. Aqueous batteries (ABs), based on water which is environmentally benign, provide a promising alternative for safe, cost-effective, and scalable energy storage, with high power density and tolerance against mishandling. Research interests and achievements in ABs have surged globally in the past 5 years. However, their large-scale application is plagued by the limited output voltage and inadequate energy density. We present the challenges in AB fundamental research, focusing on the design of advanced materials and practical applications of whole devices. Potential interactions of the challenges in different AB systems are established. A critical appraisal of recent advances in ABs is presented for addressing the key issues, with special emphasis on the connection between advanced materials and emerging electrochemistry. Last, we provide a roadmap starting with material design and ending with the commercialization of next-generation reliable ABs.Phenotypic plasticity refers to environment-induced phenotypic changes without mutation and is present in all organisms. The role of phenotypic plasticity in organismal adaptations to novel environments has attracted much attention, but its role in readaptations to ancestral environments is understudied. To address this question, we use the reciprocal transplant approach to investigate the multitissue transcriptomes of chickens adapted to the Tibetan Plateau and adjacent lowland. While many genetic transcriptomic changes had occurred in the forward adaptation to the highland, plastic changes largely transform the transcriptomes to the preferred state when Tibetan chickens are brought back to the lowland. The same trend holds for egg hatchability, a key component of the chicken fitness. These findings, along with highly similar patterns in comparable experiments of guppies and Escherichia coli, demonstrate that organisms generally "remember" their ancestral environments via phenotypic plasticity and reveal a mechanism by which past experience affects future evolution.Trans-4-hydroxy-l-proline is produced by trans-proline-4-hydroxylase with l-proline through glucose fermentation. Here, we designed a thorough "from A to Z" strategy to significantly improve trans-4-hydroxy-l-proline production. Through rare codon selected evolution, Escherichia coli M1 produced 18.2 g L-1 l-proline. Metabolically engineered M6 with the deletion of putA, proP, putP, and aceA, and proB mutation focused carbon flux to l-proline and released its feedback inhibition. It produced 15.7 g L-1 trans-4-hydroxy-l-proline with 10 g L-1 l-proline retained. Furthermore, a tunable circuit based on quorum sensing attenuated l-proline hydroxylation flux, resulting in 43.2 g L-1 trans-4-hydroxy-l-proline with 4.3 g L-1 l-proline retained. Finally, rationally designed l-proline hydroxylase gave 54.8 g L-1 trans-4-hydroxy-l-proline in 60 hours almost without l-proline remaining-the highest production to date. The de novo engineering carbon flux through rare codon selected evolution, dynamic precursor modulation, and metabolic engineering provides a good technological platform for efficient hydroxyl amino acid synthesis.