Despite the importance of the mammalian neocortex for complex cognitive processes, we still lack a comprehensive description of its cellular components. To improve the classification of neuronal cell ...types and the functional characterization of single neurons, we present Patch-seq, a method that combines whole-cell electrophysiological patch-clamp recordings, single-cell RNA-sequencing and morphological characterization. Following electrophysiological characterization, cell contents are aspirated through the patch-clamp pipette and prepared for RNA-sequencing. Using this approach, we generate electrophysiological and molecular profiles of 58 neocortical cells and show that gene expression patterns can be used to infer the morphological and physiological properties such as axonal arborization and action potential amplitude of individual neurons. Our results shed light on the molecular underpinnings of neuronal diversity and suggest that Patch-seq can facilitate the classification of cell types in the nervous system.
Deciphering the interneuronal circuitry is central to understanding brain functions, yet it remains a challenging task in neurobiology. Using simultaneous quadruple-octuple in vitro and dual in vivo ...whole-cell recordings, we found two previously unknown interneuronal circuits that link cortical layer 1-3 (L1-3) interneurons and L5 pyramidal neurons in the rat neocortex. L1 single-bouquet cells (SBCs) preferentially formed unidirectional inhibitory connections on L2/3 interneurons that inhibited the entire dendritic-somato-axonal axis of ∼1% of L5 pyramidal neurons located in the same column. In contrast, L1 elongated neurogliaform cells (ENGCs) frequently formed mutual inhibitory and electric connections with L2/3 interneurons, and these L1-3 interneurons inhibited the distal apical dendrite of >60% of L5 pyramidal neurons across multiple columns. Functionally, SBC→L2/3 interneuron→L5 pyramidal neuronal circuits disinhibited and ENGC↔L2/3 interneuron→L5 pyramidal neuronal circuits inhibited the initiation of dendritic complex spikes in L5 pyramidal neurons. As dendritic complex spikes can serve coincidence detection, these cortical interneuronal circuits may be essential for salience selection.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
The quality of on-line measured operational data is usually not satisfactory for the performance monitoring of coal-fired power plants, due to the low accuracy of measuring instrument. Data ...reconciliation is a data preprocessing technique which can improve the accuracy of measured data through process modeling and optimization, and can also be used for gross error detection together with a statistical test method. In this work, we provide a mathematical framework for gross error detection in power plants via data reconciliation. We also provide case studies to implement the proposed framework in the feed water regenerative heating system of a real-life 1000 MW ultra-supercritical coal-fired power generation unit. Data reconciliation simulation results show that the relative root mean squared errors of the primary flow measurements, namely the outlet flow rate of the #1 feed water heater, the outlet flow rate of the feed water pump, and the inlet flow rate of condensate water in the deaerator are reduced by 72%, 40%, 22%. Simulation results also show that data reconciliation is effective for accuracy improvement when estimated error standard deviations are different from the actual ones and when random errors follow generalized normal distributions. We then provide a case study where gross error detection is performed together with a global test and a serial elimination strategy, and a gross error in the measurement of outlet flow rate of the feed water pump is successfully detected and validated by the on-site inspection and maintenance records of the power plant.
•Data reconciliation and gross error detection in coal-fired power plants.•Accuracy improved for primary flow measurements through data reconciliation.•Accuracy improvement effect evaluated for non-ideal random error distributions.•Gross error identification results validated by on-site inspection records.
Although the amount of oil and gas reserves and the reservoir properties in the East China Sea Shelf Basin (ECSSB) indicate good prospects for oil and gas exploration in the Mesozoic strata, there ...has not yet been a significant breakthrough in oil and gas production. An important reason is that there are few detailed studies on the sedimentary paleogeography of the ECSSB which make it difficult to predict the distribution of sand bodies. In this paper, well-core observations, thin-section identifications, electron probe microanalysis, trace elements analysis and seismic interpretations were synthetically applied to study the sedimentary environments and the tectonic setting of the Upper Cretaceous in the southern ECSSB. In the Oujiang Sag, red mudstones and pyroclastic rocks were deposited, accompanied by wedged, chaotic pro-grading reflections in the seismic profile, indicating a volcano-alluvial fan sedimentary system. Abundant sedimentary structures including double-mud drapes, asymmetric herringbone cross-beddings and burrows, such as Planolites and Skolithos, were developed in the Minjiang Sag, typically indicating a high-energy tidal environment. The autogenetic glauconites in situ and the fossil Tintinnid also indicate a shallow marine environment. The resulting sedimentary characteristics are in accordance with the littoral facies revealed by the seismic reflections in the Minjiang Sag. Moreover, volcanic conduit facies, effusive facies, and pyroclastic facies were also recognized in the seismic profile in the Minjiang Sag. Therefore, it was presumed that subaqueous volcanic eruptions occurred in the Minjiang Sag. In the Keelung Sag, the littoral facies were dominant. The tectonic setting of the Upper Cretaceous in the southern ECSSB is the transitional arc accompanied by large-scale volcanic activities. In conclusion, the volcano-alluvial fan sedimentary system was developed in the Oujiang Sag and volcano-littoral sedimentary system was developed from the Minjiang Sag to the Keelung Sag. This study is intended to promote the understanding of the sedimentary paleogeography of the Upper Cretaceous in the southern ECSSB and to provide help in oil and gas exploration.
Neurons exhibit a rich diversity of morphological phenotypes, electrophysiological properties, and gene-expression patterns. Understanding how these different characteristics are interrelated at the ...single-cell level has been difficult because of the lack of techniques for multimodal profiling of individual cells. We recently developed Patch-seq, a technique that combines whole-cell patch-clamp recording, immunohistochemistry, and single-cell RNA-sequencing (scRNA-seq) to comprehensively profile single neurons from mouse brain slices. Here, we present a detailed step-by-step protocol, including modifications to the patching mechanics and recording procedure, reagents and recipes, procedures for immunohistochemistry, and other tips to assist researchers in obtaining high-quality morphological, electrophysiological, and transcriptomic data from single neurons. Successful implementation of Patch-seq allows researchers to explore the multidimensional phenotypic variability among neurons and to correlate gene expression with phenotype at the level of single cells. The entire procedure can be completed in ∼2 weeks through the combined efforts of a skilled electrophysiologist, molecular biologist, and biostatistician.
Induction of sex reversal of XY fish has been restricted to the sex undifferentiated period. In the present study, differentiated XY tilapia were treated with trilostane (TR), metopirone (MN) and ...glycyrrhetinic acid (GA) (inhibitor of 3β-HSD, Cyp11b2 and 11β-HSD, respectively) alone or in combination with 17β-estradiol (E2) from 30 to 90 dah (days after hatching). At 180 dah, E2 alone resulted in 8.3%, and TR, MN and GA alone resulted in no secondary sex reversal (SSR), whereas TR + E2, MN + E2 and GA + E2 resulted in 88.3, 60.0 and 46.7% of SSR, respectively. This sex reversal could be rescued by simultaneous administration of 11-ketotestosterone (11-KT). Compared with the control XY fish, decreased serum 11-KT and increased E2 level were detected in SSR fish. Immunohistochemistry analyses revealed that Cyp19a1a, Cyp11b2 and Dmrt1 were expressed in the gonads of GA + E2, MN + E2 and TR + E2 SSR XY fish at 90 dah, but only Cyp19a1a was expressed at 180 dah. When the treatment was applied from 60 to 120 dah, TR + E2 resulted in 3.3% of SSR, MN + E2 and GA + E2 resulted in no SSR. These results demonstrated that once 11-KT was synthesized, it could antagonize E2-induced male-to-female SSR, which could be abolished by simultaneous treatment with the inhibitor of steroidogenic enzymes. The upper the enzyme was located in the steroidogenic pathway, the higher SSR rate was achieved when it was inhibited as some of the precursors, such as androstenedione, testosterone and 5α-dihydrotestosterone, could act as androgens. These results highlight the key role of androgen in male sex maintenance.
Layer 4 (L4) of mammalian neocortex plays a crucial role in cortical information processing, yet a complete census of its cell types and connectivity remains elusive. Using whole-cell recordings with ...morphological recovery, we identified one major excitatory and seven inhibitory types of neurons in L4 of adult mouse visual cortex (V1). Nearly all excitatory neurons were pyramidal and all somatostatin-positive (SOM
) non-fast-spiking interneurons were Martinotti cells. In contrast, in somatosensory cortex (S1), excitatory neurons were mostly stellate and SOM
interneurons were non-Martinotti. These morphologically distinct SOM
interneurons corresponded to different transcriptomic cell types and were differentially integrated into the local circuit with only S1 neurons receiving local excitatory input. We propose that cell type specific circuit motifs, such as the Martinotti/pyramidal and non-Martinotti/stellate pairs, are used across the cortex as building blocks to assemble cortical circuits.
In a coal-fired power generation unit, steam turbine performance monitoring relies on steam cycle heat balance analysis, in which the primary flow measurement accuracy is critical. However, in a ...steam turbine on-line measurement system, the accuracy of most flow metering devices is not satisfactory, and using data measured with these devices could lead to high uncertainty in the heat balance analysis and performance monitoring results. In this work, we propose a data reconciliation approach in steam turbine on-line performance monitoring, with the aim of reducing uncertainty of the primary flow measurements and steam turbine heat rate. The proposed method is based on the establishment of a first-principle mathematical model of a steam turbine unit and optimization of the reconciled values of measurements. Results of a case study carried out on a real-life 1000 MW ultra-supercritical unit show that, after data reconciliation, uncertainties of measured values of the outlet flow rate of the #1 feed water heater, the outlet flow rate of the feed water pump, and the inlet flow rate of condensate water in the deaerator can be reduced by 72.1%, 39.4% and 21.4%, and that uncertainty of the steam turbine heat rate can be reduced by 17.9%, 18.8% and 18.8%, when the unit operates at 100%, 75% and 50% of its design load.
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•Data reconciliation application to steam turbine on-line performance monitoring systems.•Uncertainties reduced for primary flow measurements through data reconciliation.•Uncertainties reduced for steam turbine heat rate with the unit operating at design and off-design load rates.•Impact of data reconciliation on heat rate sensitivity coefficients analyzed.
•Integrated framework provided for both sensor and equipment performance monitoring.•Improved measurement gross error detection ability.•Accurate dominant factor modeling and validated test statistic ...distribution property.•Application in the feed water regenerative heating system of a coal-fired power plant.
Power plant on-line measured operational data are often corrupted with random and gross errors. The data reconciliation method can reduce the impact of random errors by adjusting redundant measurements to satisfy system constraints and detect gross errors together with a statistical test method. In previous studies, the data reconciliation method is mainly used to deal with measurements with random and gross errors, and its application is mainly in the data preprocessing areas. In this work, we extend the data reconciliation and gross error detection method to cover both sensor and equipment performance monitoring in power plants, through introducing equipment characteristic constraints together with characteristic parameter dominant factor models in the data reconciliation method. The validity and capability of the proposed framework are illustrated with case studies in the feed water regenerative heating system of a 1000MW ultra-supercritical coal-fired power generation unit. Case study results show that the characteristic parameter dominant factor models have relative root mean squared errors smaller than 2.3%, whilst the distribution properties of the test statistics for the integrated sensor and equipment performance monitoring are validated with simulated test statistic samples. We also illustrate that the proposed framework can efficiently detect and identify both sensor biases and equipment faults in the system. At the same time, the ability of the data reconciliation and global test method for measurement gross error detection is also improved due to the increased system redundancy under the proposed framework.
Neocortical feedback is critical for attention, prediction, and learning. To mechanically understand its function requires deciphering its cell-type wiring. Recent studies revealed that feedback ...between primary motor to primary somatosensory areas in mice is disinhibitory, targeting vasoactive intestinal peptide-expressing interneurons, in addition to pyramidal cells. It is unknown whether this circuit motif represents a general cortico-cortical feedback organizing principle. Here we show that in contrast to this wiring rule, feedback between higher-order lateromedial visual area to primary visual cortex preferentially activates somatostatin-expressing interneurons. Functionally, both feedback circuits temporally sharpen feed-forward excitation eliciting a transient increase-followed by a prolonged decrease-in pyramidal cell activity under sustained feed-forward input. However, under feed-forward transient input, the primary motor to primary somatosensory cortex feedback facilitates bursting while lateromedial area to primary visual cortex feedback increases time precision. Our findings argue for multiple cortico-cortical feedback motifs implementing different dynamic non-linear operations.
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