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The metal-free reductiveiN/i-trifluoroethylation andiN/i-trifluoroacetylation of indoles have been developed. Bench stable and inexpensive trimethylamine borane and trifluoroacetic acid (TFA) were utilized as the reductive and fluorinating reagents, respectively. These transformations were switchable on the basis of altering the loading of trimethylamine borane and TFA. Preliminary experiments indicated indoline was the common intermediate in these two transformations.

The coupling and coordination of digital economy and urban–rural integration can help narrow the urban–rural gap and help realize comprehensive modernization. Based on the data of 31 provinces in China from 2011 to 2020, the index systems of digital economy and urban–rural integration were constructed, respectively, by using the entropy method, and the coupling coordination degree between digital economy and urban–rural integration was calculated by using the coupling coordination degree model. The spatio-temporal evolution characteristics were analyzed by using the spatial Durbin model, and the influencing factors of the coupling coordination degree were deeply decomposed. The results showed that the coupling coordination degree of digital economy and urban–rural integration has been significantly improved in the whole country during the decade, with the overall spatial distribution characteristics of “high in the east and low in the west” and “high in the south and low in the north”. The growth momentum of the backward provinces was relatively better, which have more obvious characteristics of positive spatial agglomeration. The level of economic development, government support, technological innovation and industrial structure had positive promoting effects on the coupling coordination degree. Except for the negative spatial spillover effect of government support, the three other factors all had promoting effects on the coupling coordination degree in neighboring provinces. The effect intensity of influencing factors also had regional heterogeneity.

Taiwan is located in the subtropical monsoon region, both typhoons and vigorous convection caused by strong southwesterly flow develop seasonal compound disasters.In addition, the response time for early warning systems of the reservoirs and downstream riverbanks has been shortened due to higher frequency and greater intensity of short-duration rainfall events in recent years. Past studies pointed out that the current water level forecast does not consider the outflow discharge of the reservoir. Therefore, this study proposes a downstream water level forecasting model that considers the outflow discharge of the reservoir, and the model is provided to relevant hazard mitigation centers.This research has selected the water level of the Taipei bridge as target status and collected data of typhoon and storm events from 2014-2021. These data included the precipitation in the watershed of upstream of Taipei bridge, outflow discharge of Shimen reservoir, outflow discharge of Feitsui reservoir, and tidal of Tamsui river estuary as the alternative factors. Subsequently, building several models based on multiple machine learning, such as RNN, SVM, and LSTM to interface with the constant-quantity rainfall forecast of the Central Weather Bureau, then produce the forecast in the future 12 hours with Multi-Step Forecasting (MSF) about the water level of Taipei bridge. The result shows that SVM, RNN, LSTM forecast in the future 1 hour precisely, which statistical values of CC are more than 0.97, and root mean square errors of water level are around 0.2 m. As the forecast time is longer, the statistical values of CC decrease around 0.93 and root mean square errors of water level increase around 0.3 m.However, LSTM is able to learn dependencies between the time series and get more precise outcomes than the SVM and RNN, which is not outstanding initially then performs the best at the last. The proposed water level forecast is proved to improve the accuracy of the forecast in the future 12 hours about the water level of Taipei bridge. Moreover, by coordinating the Quantitative Precipitation Forecast (QPF) and warning water level, the model provides early warning of the future twelve-hour water level, which is not only beneficial to evacuation and operating traversing dock-gate and evacuation gates efficiently, but also conducive to reducing the risk of losses in life and property.Keywords: Water level, Quantitative Precipitation Forecast, Machine learning, Multi-Step Forecasting

Transformations among Stemona alkaloids with different ring systems have improved the synthetic efficiency toward diverse alkaloids. Recent advances in the transformations of different types of Stemona alkaloids were reviewed for the first time.

Herein, we report a Rh(iii)-catalyzed C–H functionalization of indoles at the C4 position with alkylidenecyclopropanes (ACPs).

An indazolone-directed chemoselective synthesis of 8H-indazolo [1,2-a]cinnolines has been realized via a cascade Cp*Ir(iii)- and Cp*Rh(iii)-catalyzed C–H activation/cyclization reaction of 1-arylindazolones with sulfoxonium ylides.

A tandem rhodium(III)-catalyzed system was established to access 3,4-dihydroisoquinolin-1(2H)-one by coupling of N-methoxy-3-methylbenzamide with 2-methylidenetrimethylene carbonate. This one-pot synthesis protocol processed smoothly under mild reaction conditions. Moreover, a total of 28 examples, broad substrate scope, and high functional-group compatibility were observed. Preliminary mechanism studies were also conducted and demonstrated that the rhodium(III) catalyst played a vital role in the C-H-allylation and N-alkylation cyclization process.

A metal-free tandem reduction and N-trifluoroethylation of quinolines and quinoxalines has been developed using trifluoroacetic acid as an inexpensive fluorinating source in the presence of Me3N–BH3.

β-Nitro alcohol, α-nitro ketone and nitro nitratosation compounds were synthesized via radical nitration of alkylidenecyclopropanes and alkylidenecyclobutanes with Fe(NO3)3·9H2O or AgNO2.

SUMMARYThe dorsomedial posterior parietal cortex is part of a higher-cognition network implicated in elaborate processes underpinning memory formation, recollection, episodes reconstruction, and temporal information processing. Neural coding for complex episodic processing is however under-documented. Here we revealed a set of neural codes of “neuroethogram” in the primate parietal cortex. Analyzing neural responses in macaque dmPPC to naturalistic videos, we discovered several groups of neurons that are sensitive to different categories of ethogram-items and to low-level sensory features, as well as saccadic eye movement. The amount of information coded within these multiplex representations in turn increases our trained classifier decodability for different video-types. We also discovered that the processing of category and feature information by these neurons is sustained by accumulation of temporal information over a long timescale up to 30 s, corroborating its reported long temporal receptive windows. We performed an additional behavioral experiment and found that saccade-related activities could not account for the mixed neuronal responses elicited by the video stimuli. We further observed monkeys’ scan-paths and gaze consistency are modulated by video content. Taken altogether, these neural findings explain how dorsomedial PPC weaves fabrics of ongoing experiences together in real-time. The high dimensionality of neural representations should motivate us to shift the focus of attention from pure selectivity neurons to mixed selectivity neurons, especially in increasingly complex naturalistic task designs.HIGHLIGHTSNeural codes for “neuroethogram” in macaque dorsomedial parietal cortexParietal neural codes exhibit mixed selectivity of event featuresDorsomedial PPC neurons support a long temporal receptive window for episodesSaccadic movement could not explain away mixed neuronal responsesEye movement scan-path and gaze consistency shown across viewing repetitions

Perceptual decision-making is increasingly being understood to involve an interaction between bottom-up sensory-driven signals and top-down choice-driven signals, but how these signals interact to mediate perception is not well understood. The parieto-insular vestibular cortex (PIVC) is an area with prominent vestibular responsiveness, and previous work has shown that inactivating PIVC impairs vestibular heading judgments. To investigate the nature of PIVC's contribution to heading perception, we recorded extracellularly from PIVC neurons in two male rhesus macaques during a heading discrimination task, and compared findings with data from previous studies of dorsal medial superior temporal (MSTd) and ventral intraparietal (VIP) areas using identical stimuli. By computing partial correlations between neural responses, heading, and choice, we find that PIVC activity reflects a dynamically changing combination of sensory and choice signals. In addition, the sensory and choice signals are more balanced in PIVC, in contrast to the sensory dominance in MSTd and choice dominance in VIP. Interestingly, heading and choice signals in PIVC are negatively correlated during the middle portion of the stimulus epoch, reflecting a mismatch in the polarity of heading and choice signals. We anticipate that these results will help unravel the mechanisms of interaction between bottom-up sensory signals and top-down choice signals in perceptual decision-making, leading to more comprehensive models of self-motion perception.SIGNIFICANCE STATEMENTVestibular information is important for our perception of self-motion, and various cortical regions in primates show vestibular heading selectivity. Inactivation of the macaque vestibular cortex substantially impairs the precision of vestibular heading discrimination, more so than inactivation of other multisensory areas. Here, we record for the first time from the vestibular cortex while monkeys perform a forced-choice heading discrimination task, and we compare results with data collected previously from other multisensory cortical areas. We find that vestibular cortex activity reflects a dynamically changing combination of sensory and choice signals, with both similarities and notable differences with other multisensory areas.

A metal-free coupling of quinoxalin-2(1H)-ones with tert-butyl nitrite has been developed. Distinctly from the previous functionalization of quinoxalin-2(1H)-ones, this nitration reaction took place selectively at the C7 or C5 position of the phenyl ring, affording a series of 7-nitro and 5-nitro quinoxalin-2(1H)-ones in moderate to good yields. Preliminary mechanistic studies revealed that the reaction may involve a radical process.

A one-pot method for the synthesis of azo compounds by the reaction of β-naphthol with aryl amines using t-BuONO as the nitrosonium source in DCM at room temperature was developed. This method features mild reaction conditions, a simple experimental procedure, and is free of acidic or alkaline additives.

Photoreceptor degeneration diseases, such as retinitis pigmentosa and age-related macular degeneration, are major causes of blindness. Photovoltaic devices or materials activates retinal cells in response to light, hence are promising retinal prosthesis in treating blind patients. The restoration of image-forming vision with high sensitivity is the key. Here we demonstrated that Au nanoparticle-coated titania (TiO2-x) nanowire (NW) arrays can restore vision in blind mice and non-human primates with photoreceptor degeneration. We first showed that blind mice with subretinal implant of NW arrays were capable of detecting static, moving and flashing objects with low light intensity threshold for 22 months, having a visual acuity of 0.3 cpd (0.4 cpd in normal mice). Results in chronic in vivo calcium imaging in primary visual cortex (V1) collectively suggested the plastic change in V1 neurons as well as the improvement in visual information encoding for natural images after NW implant. What’s more, macaque monkeys with subretinal implant of NW arrays were capable of detecting an LED of 0.5º in diameter at 10 μW·mm-2 in visually-guided saccade experiments. Our findings opened up the possibility to utilize nanomaterials as artificial photoreceptors to ameliorate visual deficits of patients with photoreceptor degeneration.

A metal-free coupling of quinoxalin-2(1

A tandem rhodium(III)-catalyzed system was established to access 3,4-dihydroisoquinolin-1(2

Syntaxin 4 (STX4), a plasma membrane-localized SNARE protein, regulates human islet β-cell insulin secretion and preservation of β-cell mass. We found that human type 1 diabetic (T1D) and non-obese diabetic (NOD) mouse islets show reduced β-cell STX4 expression, consistent with decreased STX4 expression as a potential driver of T1D phenotypes. To test this hypothesis, we generated inducible β-cell-specific STX4-expressing NOD mice (NOD-iβSTX4). Of NOD-iβSTX4 mice, 73% had sustained normoglycemia versus + Treg cells were also enriched in NOD-iβSTX4 islets. These results provide a deeper mechanistic understanding of STX4 function in β-cell protection and warrant further investigation of STX4 enrichment as a strategy to reverse or prevent T1D in humans or protect β-cell grafts.