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A fundamental interest in developmental neuroscience lies in the ability to map the complete single-cell lineages within the brain. To this end, we developed a CRISPR editing-based lineage-specific tracing (CREST) method for clonal tracing in Cre mice. We then used two complementary strategies based on CREST to map single-cell lineages in developing mouse ventral midbrain (vMB). By applying snapshotting CREST (snapCREST), we constructed a spatiotemporal lineage landscape of developing vMB and identified six progenitor archetypes that could represent the principal clonal fates of individual vMB progenitors and three distinct clonal lineages in the floor plate that specified glutamatergic, dopaminergic or both neurons. We further created pandaCREST (progenitor and derivative associating CREST) to associate the transcriptomes of progenitor cells in vivo with their differentiation potentials. We identified multiple origins of dopaminergic neurons and demonstrated that a transcriptome-defined progenitor type comprises heterogeneous progenitors, each with distinct clonal fates and molecular signatures. Therefore, the CREST method and strategies allow comprehensive single-cell lineage analysis that could offer new insights into the molecular programs underlying neural specification.

The estimation of valve stiction model is studied. In industrial applications, valve outputs are often not available, the stiction nonlinear block appears before a linear dynamic block which is operation in a closed-loop system. By parameterizing the valve stiction model as a form of cubic splines, an identification method is proposed using a relaxation iteration scheme. Parameter estimation for the linear part is accomplished through a two-stage procedure. Firstly, an unbiased estimation is obtained by the high-order ARX (AutoRegressive exogenous) model. Then the ARX model is reduced to a Box-Jenkins model. The consistency of the method is established. Simulation data sets and real operation data sets are used to illustrate the method.

The cell lineages across developmental stages remain to be elucidated. Here, we developed single-cell split barcoding (SISBAR) that allows clonal tracking of single-cell transcriptomes across stages in an in vitromodel of human ventral midbrain-hindbrain differentiation. We developed “potential-spective” and “origin-spective” analyses to investigate the cross-stage lineage relationships and mapped a multi-level clonal lineage landscape depicting the whole differentiation process. We uncovered many previously uncharacterized converging and diverging trajectories. Furthermore, we demonstrate that a transcriptome-defined cell type can arise from distinct lineages that leave molecular imprints on their progenies, and the multilineage fates of a progenitor cell-type represent the collective results of distinct rather than similar clonal fates of individual progenitors, each with distinct molecular signatures. Specifically, we uncovered a ventral midbrain progenitor cluster as the common clonal origin of midbrain dopaminergic (mDA) neurons, midbrain glutamatergic neurons, and vascular and leptomeningeal cells and identified a surface marker that can improve graft outcomes.

Transplantation of human pluripotent stem cell (hPSC)-derived neurons is a promising avenue for treating disorders including Parkinson’s disease (PD). Precise control over engrafted cell activity is highly desired, as cells do not always integrate properly into host circuitry and can cause suboptimal graft function or undesired outcomes. Here, we show tunable rescue of motor function in a mouse model of PD, following transplantation of human midbrain dopaminergic (mDA) neurons differentiated from hPSCs engineered to express DREADDs (designer receptors exclusively activated by designer drug). Administering clozapine-N-oxide (CNO) enabled precise DREADD-dependent stimulation or inhibition of engrafted neurons, revealing D1 receptor-dependent regulation of host neuronal circuitry by engrafted cells. Transplanted cells rescued motor defects, which could be reversed or enhanced by CNO-based control of graft function, and activating engrafted cells drives behavioral changes in transplanted mice. These results highlight the ability to exogenously and noninvasively control and refine therapeutic outcomes following cell transplantation.

Precise temporal control of gene expression or deletion is critical for elucidating gene function in biological systems. However, the establishment of human pluripotent stem cell (hPSC) lines with inducible gene knockout (iKO) remains challenging. We explored building iKO hPSC lines by combining CRISPR/Cas9-mediated genome editing with the Flp/FRT and Cre/LoxP system. We found that “dual-sgRNA targeting” is essential for biallelic knockin of FRT sequences to flank the exon. We further developed a strategy to simultaneously insert an activity-controllable recombinase-expressing cassette and remove the drug-resistance gene, thus speeding up the generation of iKO hPSC lines. This two-step strategy was used to establish human embryonic stem cell (hESC) and induced pluripotent stem cell (iPSC) lines with iKO of SOX2, PAX6, OTX2, and AGO2,genes that exhibit diverse structural layout and temporal expression patterns. The availability of iKO hPSC lines will substantially transform the way we examine gene function in human cells.

Presently, most enterprises have transformed into a link of the whole supply chain by means of forming groups, dummy enterprises or strategic leagues of the industry chain established by joint shares, etc. These enterprises are able to maximize the whole profit of the industry chain while providing the maximum value for each of their clients in accordance with their demand. The management of the industry chain endows logistic management with new significance and functions. The thesis probes into the general strategies for logistic management under the conditions of industry chains by using a specific model so as to integrate logistics or material flow, capital flow and information flow. It describes a subdivided information-oriented enterprise that is based on the industry chain. Such enterprises emphasize particularly on the coordination among the participating enterprises in terms of goods, information and funds. This would be a win-win situation for enterprise.

For the execution and technologies related to the concept system, its innovation focuses on execution feasibility from the commercial perspective. The greatest innovation in terms of execution is in the combination of international technological trade mechanisms. In the past, many international technological transfers were erroneously interpreted and analyzed. The emphasis on the fact that the international technological transfer itself is a commercial practice is an innovative proposition. That is to say, the practices involved are in line with the international practice and the international trade rules. Only the transfer that generates profits can be considered a successful transfer. Thus this research paper proposes that the Three-tier control model for the international technological transfer become an integrated control mechanism, described the key problem in this mechanism. No matter how many standards you set, if you cannot find a real foothold in the market and generate profits, any standards are of no avail.

Ours is an epoch when stratagem will win. The strategic planning of logistics is closely related to the rise and fall of a modern enterprise. With the constant social progress and fast economic development, the social and economic environment faced by enterprises is continuously changing and there exist uncertainties of strategic planning of the logistics of enterprise. The thesis discusses about the Three-tier model, its activities and technologies in the context of the concept design. The research can not only serve as a theoretical guidance, but also be applied to the real-world issues. From the perspective of the relationship between concept design and value flow of enterprises, it advances methods of implementing logistic strategy in enterprises. To ensure the effective implementation of logistic management, a platform is indispensable that will be formed by making use of the Internet and the intranet.

Through the CV(Control Vertices), NURBS curves, NURBS surface and the shell to research the principles of AliasStudio. And at the end of the article, describing the characteristics of advanced surface design of AliasStudio.

Parameter self-setting fuzzy PID control algorithm for control drying temperature is proposed to improve the problem about big fluctuations in temperature and high pellet broken rate of traditional control on Cold pressure ball drying system in this paper, and the controller create intelligence temperature control system through combine fuzzy control and PID control. We establish fuzzy controller, preparation of fuzzy look-up table in PLC and combined with PID control module to realize fuzzy PID control algorithm, through the computer simulation to analyze the fuzzy PID controller control effect.

CHD8is a candidate gene for autism spectrum disorders and neurological development delay. It has been reported to be essential for neurogenesis in the cerebral cortex, but the function of CHD8 in cerebellum has not been comprehensively investigated. The potential relationship of cerebellum dysplasia with psychiatric disorders in patients with CHD8mutations is still not clear. In this study, we establish different conditional knockout mouse models to investigate the roles of CHD8 in cerebellar development. Mice with neural stem cell-specific Chd8deletion exhibited significant reduction of cerebellum volume and no layering structure is detected. Genetic deletion of Chd8in cerebellar granule neuron progenitors (GNPs) lead to cerebellar hypoplasia, absent of proliferation layer and ectopic of Purkinje neuron. However, no substantial cerebellar dysplasia is detected in mice with Purkinje neuron- or oligodendrocyte-specific Chd8ablation. Single-cell RNA sequencing indicates that ribosome-related genes and pathways are most significantly disrupted in GNPs, indicating the potential mechanism. Importantly, in addition to ataxia phenotype, mice with GNP-specific Chd8ablation present a neuropsychiatric phenotype in three-chamber and light/dark tests. Taken together, our results provide insights not only into the function of CHD8 in cerebellar development, but also the pathogenesis of neuropsychiatric disorders in patients with CHD8mutations.

Consider the mechanism of the formation of surface roughness, this paper establish the mechanical model of undeformed chip thickness caused by the cutting edge,and the mechanical model of cutting residues caused by the tool feed movement . By means of Brammertz equation, combining the above two mechanical model,a more perfect surface roughness mechanical mode is established.

Human brain development is a complex process involving neural proliferation, differentiation, and migration that are directed by many essential cellular factors and drivers. Here, using the NetBID2 algorithm and developing human brain RNA sequencing dataset, we identify synaptotagmin-like 3 (SYTL3) as one of the top drivers of early human brain development. Interestingly, SYTL3 exhibits high activity but low expression in both early developmental human cortex and human embryonic stem cell (hESC)-derived neurons. Knockout of SYTL3 (SYTL3-KO) in human neurons or knockdown of Sytl3 in embryonic mouse cortex markedly promotes neuronal migration. SYTL3-KO causes an abnormal distribution of deep-layer neurons in brain organoids and reduces presynaptic neurotransmitter release in hESC-derived neurons. We further demonstrate that SYTL3-KO-accelerated neuronal migration is modulated by high expression of matrix metalloproteinases. Together, based on bioinformatics and biological experiments, we identify SYTL3 as a regulator of cortical neuronal migration in human and mouse developing brains.

Although cell transplantation can rescue motor defects in Parkinson’s disease (PD) models, whether and how grafts functionally repair damaged neural circuitry in the adult brain is not known. We transplanted hESC-derived midbrain dopamine (mDA) or cortical glutamate neurons into the substantia nigraor striatum of a mouse PD model and found extensive graft integration with host circuitry. Axonal pathfinding toward the dorsal striatum was determined by the identity of the grafted neurons, and anatomical presynaptic inputs were largely dependent on graft location, whereas inhibitory versus excitatory input was dictated by the identity of grafted neurons. hESC-derived mDA neurons display A9 characteristics and restore functionality of the reconstructed nigrostriatal circuit to mediate improvements in motor function. These results indicate similarity in cell-type-specific pre- and post-synaptic integration between transplant-reconstructed circuit and endogenous neural networks, highlighting the capacity of hPSC-derived neuron subtypes for specific circuit repair and functional restoration in the adult brain.

Colorado potato beetle, Leptinotarsa decemlineata (Say) (Coleoptera: Chrysomelidae), has become the economically most important insect defoliator of potatoes, Solanum tuberosum L., in northern Xinjiang Uygur autonomous region in China. Currently, control of Colorado potato beetle relies mainly on chemical insecticides. And this may result in insecticide resistance. In this study, LD50 values were measured by a topical bioassay for 14 conventional insecticides in seven local populations from Urumqi, Changji, Tacheng, Nilka, Gongliu, Qapqal, and Tekes counties (cities). The Tekes field population was the most susceptible population and was selected as a reference strain. Compared with the Tekes strain, the Changji, Qapqal, Nilka, Tacheng, and Gongliu populations exhibited moderate to very high levels of resistance to cyhalothrin. The Qapqal and Changji populations showed a moderate and a very high resistance to deltamethrin, respectively. And the Changji population developed a high resistance against α-cypermethrin. Moreover, the Qapqal population had a moderate resistance to carbofuran, and the Urumqi population reached high level of resistance to endosulfan. Possible resistance mechanisms of the Changji and Qapqal populations were determined using three enzyme inhibitors. Triphenyl phosphate (TPP), diethylmeleate, and piperonyl butoxide (PBO) had little synergism to cyhalothrin in the two populations. In contrast, PBO and TPP exhibited some synergistic effects to carbofuran in the Qapqal population, indicating the involvement of monooxygenases and esterases in conferring carbofuran resistance. It seems that additional mechanisms, such as target site insensitivity, should play an important role in Colorado potato beetle resistances to cyhalothrin and carbofuran in northern Xinjiang local populations.