Intrinsic Stress-strain in Barium Titanate Piezocatalysts Enabling Lithium-Oxygen Batteries with Low Overpotential and Long Life.

Rechargeable lithium-oxygen (Li-O2 ) batteries with high theoretical energy density are considered as promising candidates for portable electronic devices and electric vehicles, whereas their commercial application is hindered due to poor cyclic stability caused by the sluggish kinetics and cathode passivation. Herein, the intrinsic stress originated from the growth and decomposition of the discharge product (lithium peroxide, Li2 O2 ) is employed as a microscopic pressure resource to induce the built-in electric field, further improving the reaction kinetics and interfacial Lithium ion (Li+ ) transport during cycling. Piezopotential caused by the intrinsic stress-strain of solid Li2 O2 is capable of providing the driving force for the separation and transport of carriers, enhancing the Li+ transfer, and thus improving the redox reaction kinetics of Li-O2 batteries. Combined with a variety of in situ characterizations, the catalytic mechanism of barium titanate (BTO), a typical piezoelectric material, was systematically investigated, and the effect of stress-strain transformation on the electrochemical reaction kinetics and Li+ interface transport for the Li-O2 batteries is clearly established. The findings provide deep insight into the surface coupling strategy between intrinsic stress and electric fields to regulate the electrochemical reaction kinetics behavior and enhance the interfacial Li+ transport for battery system.

Computational modelling and application of mechanical waves to detect arterial network anomalies: Diagnosis of common carotid stenosis.

BACKGROUND AND OBJECTIVE: This paper proposes a novel strategy to localize anomalies in the arterial network based on its response to controlled transient waves. The idea is borrowed from system identification theories in which wave reflections can render significant information about a target system. Cardiovascular system studies often focus on the waves originating from the heart pulsations, which are of low bandwidth and, hence, can hardly carry information about the arteries with the desired resolution. METHODS: Our strategy uses a relatively higher bandwidth transient signal to characterize healthy and unhealthy arterial networks through a frequency response function (FRF). We tested our novel approach on data simulated using a one-dimensional cardiovascular model that produced pulse waves in the larger arteries of the arterial network. Specifically, we excited the blood flow from the brachial artery with a relatively high bandwidth flow disturbance and collected the subsequent pressure waveform at peripheral positions. To better differentiate FRFs of healthy and unhealthy networks, we used a FRF that removes the effects of heart pulsations. RESULTS: Results demonstrate the ability of the proposed FRF to detect and follow-up on the development of a common carotid artery (CCA) stenosis. We tested distinct geometrical variations of the stenosis (size, length and position) and observed differences between the FRFs of healthy and unhealthy networks in all cases; such differences were mainly due to geometrical variations determined by the stenosis. CONCLUSIONS: We have provided a theoretical proof of concept that demonstrates the ability of our novel strategy to detect and track the development of CCA stenosis by using peripheral pressure waves that can be measured non-invasively in clinical practice.

All-Solid-State Photo-Assisted Li-CO2 Battery Working at an Ultra-Wide Operation Temperature.

At present, photoassisted Li-air batteries are considered to be an effective approach to overcome the sluggish reaction kinetics of the Li-air batteries. And, the organic liquid electrolyte is generally adopted by the current conventional photoassisted Li-air batteries. However, the superior catalytic activity of photoassisted cathode would in turn fasten the degradation of the organic liquid electrolyte, leading to limited battery cycling life. Herein, we tame the above limitation of the traditional liquid electrolyte system for Li-CO2 batteries by constructing a photoassisted all-solid-state Li-CO2 battery with an integrated bilayer Au@TiO2/Li1.5Al0.5Ge1.5(PO4)3 (LAGP)/LAGP (ATLL) framework, which can essentially improve battery stability. Taking advantage of photoelectric and photothermal effects, the Au@TiO2/LAGP layer enables the acceleration of the slow kinetics of the carbon dioxide reduction reaction and evolution reaction processes. The LAGP layer could resolve the problem of liquid electrolyte decomposition under illumination. The integrated double-layer LAGP framework endows the direct transportation of heat and Li+ in the entire system. The photoassisted all-solid-state Li-CO2 battery achieves an ultralow polarization of 0.25 V with illumination, as well as a high round-trip efficiency of 92.4%. Even at an extremely low temperature of -73 °C, the battery can still deliver a small polarization of 0.6 V by converting solar energy into heat to achieve self-heating. This study is not limited to the Li-air batteries but can also be applied to other battery systems, constituting a significant step toward the practical application of all-solid-state photoassisted Li-air batteries.

Nitro-Decorated Microporous Covalent Organic Framework (TpPa-NO2) for Selective Separation of C2H4 from a C2H2/C2H4/CO2 Mixture and CO2 Capture.

A nitro-decorated microporous covalent organic framework, TpPa-NO2, has been synthesized in a gram scale with a one-pot reaction. It can effectively selectively separate C2H4 from a C2H2/C2H4/CO2 mixture and capture CO2 from CO2/N2 based on ideal adsorption solution theory calculations and transient breakthrough experiments. Theoretical calculations illustrated that the hydrogen atoms of imine bonds, carbonyl oxygen, and nitro group show high affinity toward C2H2 and CO2, playing vital roles in efficient separation.

Oxygen Vacancy-Mediated Growth of Amorphous Discharge Products toward an Ultrawide Band Light-Assisted Li-O2 Batteries.

Photoassisted electrochemical reaction is regarded as an effective approach to reduce the overpotential of lithium-oxygen (Li-O2 ) batteries. However, the achievement of both broadband absorption and long term battery cycling stability are still a formidable challenge. Herein, an oxygen vacancy-mediated fast kinetics for a photoassisted Li-O2 system is developed with a silver/bismuth molybdate (Ag/Bi2 MoO6 ) hybrid cathode. The cathode can offer both double advantages for light absorption covering UV to visible region and excellent electrochemical activity for O2 . Upon discharging, the photoexcited electrons from Ag nanoplate based on the localized surface plasmon resonance (LSPR) are injected into the oxygen vacancy in Bi2 MoO6 . The fast oxygen reaction kinetics generate the amorphous Li2 O2 , and the discharge plateau is improved to 3.05 V. Upon charging, the photoexcited holes are capable to decompose amorphous Li2 O2 promptly, yielding a very low charge plateau of 3.25 V. A first cycle round-trip efficiency is 93.8% and retention of 70% over 500 h, which is the longest cycle life ever reported in photoassisted Li-O2 batteries. This work offers a general and reliable strategy for boosting the electrochemical kinetics by tailoring the crystalline of Li2 O2 with wide-band light.

Foul sewer model development using geotagged information and smart water meter data.

Hydraulic modeling of a foul sewer system (FSS) enables a better understanding of the behavior of the system and its effective management. However, there is generally a lack of sufficient field measurement data for FSS model development due to the low number of in-situ sensors for data collection. To this end, this study proposes a new method to develop FSS models based on geotagged information and water consumption data from smart water meters that are readily available. Within the proposed method, each sewer manhole is firstly associated with a particular population whose size is estimated from geotagged data. Subsequently, a two-stage optimization framework is developed to identify daily time-series inflows for each manhole based on physical connections between manholes and population as well as sewer sensor observations. Finally, a new uncertainty analysis method is developed by mapping the probability distributions of water consumption captured by smart meters to the stochastic variations of wastewater discharges. Two real-world FSSs are used to demonstrate the effectiveness of the proposed method. Results show that the proposed method can significantly outperform the traditional FSS model development approach in accurately simulating the values and uncertainty ranges of FSS hydraulic variables (manhole water depths and sewer flows). The proposed method is promising due to the easy availability of geotagged information as well as water consumption data from smart water meters in near future.

Machine learning based marine water quality prediction for coastal hydro-environment management.

During the past three decades, harmful algal blooms (HAB) events have been frequently observed in marine waters around many coastal cities in the world including Hong Kong. The increasing occurrence of HAB has caused acute influences and damages on water environment and marine aquaculture with millions of monetary losses. For example, the Tolo Harbour is one of the most affected areas in Hong Kong, where more than 30% HAB occurred. In order to forewarn the potential HAB incidents, the machine learning (ML) methods have been increasingly resorted in modelling and forecasting water quality issues. In this study, two different ML methods - artificial neural networks (ANN) and support vector machine (SVM) - are implemented and improved by introducing different hybrid learning algorithms for the simulations and comparative analysis of more than 30-year measured data, so as to accurately forecast algal growth and eutrophication in Tolo Harbour in Hong Kong. The application results show the good applicability and accuracy of these two ML methods for the predictions of both trend and magnitude of the algal growth. Specifically, the results reveal that ANN is preferable to achieve satisfactory results with quick response, while the SVM is suitable to accurately identify the optimal model but taking longer training time. Moreover, it is demonstrated that the used ML methods could ensure robustness to learn complicated relationship between algal dynamics and different coastal environmental variables and thereby to identify significant variables accurately. The results analysis and discussion of this study also indicate the potentials and advantages of the applied ML models to provide useful information and implications for understanding the mechanism and process of HAB outbreak and evolution that is helpful to improving the water quality prediction for coastal hydro-environment management.

Retrospective Study of the Etiology and Risk Factors of Systemic Inflammatory Response Syndrome After Systematic Transrectal Ultrasound-Guided Prostate Biopsy.

OBJECTIVE: To explore the risk factors, pathogenic bacteria distribution and drug resistance of systematic transrectal ultrasound-guided prostate biopsy (TRUS-Bx), 329 cases of TRUS-Bx were collected, retrospectively, in the Second Affiliated Hospital, Army Military Medical University, from April 2017 to October 2019. METHODS: A total of 329 cases were all qualified and grouped into the SIRS group (25 cases) and the non-SIRS group (304 cases). Of all the cases, incidence and risk factors of systemic inflammatory response syndrome (SIRS) were analyzed. Urine and blood samples of patients with SIRS after TRUS-Bx were also collected for bacterial culture and drug sensitivity test. RESULTS: Multivariate logistic regression analysis showed that BMI ≥ 25 kg/m2 (OR = 1.66, 95% CI = 1.34-2.12, P <0.001), history of diabetes (OR = 5.48, 95% CI = 1.53-19.68, P = 0.008), urinary infection before operation (OR = 9.19, 95% CI = 2.92-20.93, P < 0.001) and erythrocyte sedimentation (ESR) ≥ 20 mm/h (OR = 1.04, 95% CI = 1.01-1.08, P = 0.039) were independent risk factors of SIRS after TURS-PB. CONCLUSION: The incidence of SIRS and urinary sepsis was 7.59% and 2.13%, respectively, and major pathogens of SIRS after TRUS-Bx were Escherichia coli (58.33%), Klebsiella pneumoniae (12.5%) and Pseudomonas aeruginosa (12.5%). Imipenem, meropenem, tigecycline, piperacillin/tazobactam, teicoplanin, vancomycin, amikacin and cefoperazone/sulbactam had a very strong inhibitory effect to those pathogenic bacteria (sensitivity 85.72%~100%). Levofloxacin, ciprofloxacin, gentamicin, penicillin G, compound neonomine and second-generation cephalosporins showed less but also worked as a good inhibitor to pathogenic bacteria (42.86%~80.95%).

Morphological environment survey and hydrodynamic modeling of a large bifurcation-confluence complex in Yangtze River, China.

Since the establishment of the world-class Three Gorges Dam (TGD) across the Yangtze River, China, the downstream reach has experienced a long-term adjustment with regard to the river morphology and hydrodynamics, imposing a profound impact on the environmental conditions of human living and aquatic ecosystem. This study presents an investigation on the river channel morphological characteristics and hydrodynamic environment of a large bifurcation-confluence complex downstream of the TGD through detailed field survey and numerical modeling. Results show that the main stem, before being bifurcated into two sub-channels (the North Channel and the South Channel), experiences a meander, leading to the severe bed scouring near the outer bank (pools) resulted from a high flow mass flux and bed shear stress. Because of being bifurcated, the river width with largely growing may result in the reduction of flow velocity and sediment deposition (riffles), and thereby two plugbars are formed near the entrance of two sub-channels. In the meantime, the velocity-reversal phenomenon (flow velocity and friction velocity) is identified when low flows are transited into high flows. The flow mass flux, however, is always larger in pool regions, which is highly related to water depth. As a result, the topographic steering of flows by riffles, bars and floodplains may have more impact on flow path under low flow conditions, while the bankline shape would become more important under high flows. Furthermore, the topographic steering could play a key role in the pattern of flow separations near the confluence. More interestingly, the confluence flow separation only occurs under low flow conditions and its occurring location shifts upwards the tributary (the North Channel), which differs from observations in previous studies. The visualized numerical results of friction velocity distribution indicate that sediment is more likely to deposit in the North Channel (entrance) with lower friction velocity, implying the potential closure of the sub-channel.

Tuning lithium-peroxide formation and decomposition routes with single-atom catalysts for lithium-oxygen batteries.

Lithium-oxygen batteries with ultrahigh energy density have received considerable attention as of the future energy storage technologies. The development of effective electrocatalysts and a corresponding working mechanism during cycling are critically important for lithium-oxygen batteries. Here, a single cobalt atom electrocatalyst is synthesized for lithium-oxygen batteries by a polymer encapsulation strategy. The isolated moieties of single atom catalysts can effectively regulate the distribution of active sites to form micrometre-sized flower-like lithium peroxide and promote the decomposition of lithium peroxide by a one-electron pathway. The battery with single cobalt atoms can operate with high round-trip efficiency (86.2%) and long-term stability (218 days), which is superior to a commercial 5 wt% platinum/carbon catalyst. We reveal that the synergy between a single atom and the support endows the catalyst with excellent stability and durability. The promising results provide insights into the design of highly efficient catalysts for lithium-oxygen batteries and greatly expand the scope of future investigation.

Process for a Free-Standing and Stable All-Metal Structure for Symmetrical Lithium-Oxygen Batteries.

A number of inherent and thorny obstacles still stand in the way of the practical application of Li-O2 batteries, which require development of an advanced lithium anode and O2 cathode. Herein, the strategy of a symmetrical Li-O2 battery is presented. Specifically, Cu nanoneedle arrays with a nanoengineered Au coating are grown directly on a Cu foam substrate (Au/Cu@FCu), which can act as both the anode backbone and the cathode in a Li-O2 battery. The excellent conductivity, high porosity, large specific surface, and superior lithiophilicity as well as high catalytic activity of the Au/Cu@FCu electrodes can simultaneously regulate the deposition behavior of the lithium metal in the anode and catalyze the formation/decomposition of Li2O2 in the cathode. As a result, the Li uniformly deposited on the Au/Cu@FCu anode without Li dendrites, showing a high Coulombic efficiency over 96% and a long and stable cycle lifetime over 970 h. At the same time, the Au/Cu@FCu cathode demonstrates extremely low overpotentials (0.64 V) and a much higher specific capacity of 27 270 mAh g-1 compared to the Li-O2 batteries with a carbon-free cathode reported to date. Moreover, the "ebb and flow" phenomenon of the anode and cathode morphology is also observed in the Li-O2 battery.

1,1-Diphenylvinylsulfide as a Functional AIEgen Derived from the Aggregation-Caused-Quenching Molecule 1,1-Diphenylethene through Simple Thioetherification.

An efficient and readily scalable thioetherification between 1,1-diphenylethene (DPE) and sodium arylsulfinate was developed for the synthesis of 1,1-diphenylvinylsulfide (DPVS) with the yield up to 99 %. The photophysical properties of DPVS show that the introduction of arylsulfenyl groups onto the parent molecule DPE makes DPVS a novel type of aggregation-induced emission (AIE) luminogen (AIEgen) with large Stoke's shift (up to 188 nm). These DPVS possess AIE properties due to restriction of intramolecular motions (RIM), as demonstrated by crystal structure analysis. Importantly, the AIE performance of DPVS can be applied to sense the nitroaromatic explosive picric acid in aqueous systems through a "turn-off" response.

ZNF488 is an independent prognostic indicator in nasopharyngeal carcinoma and promotes cell adhesion and proliferation via collagen IV/FAK/AKT/Cyclin D1 pathway.

Background: ZNF488 acts as an oncogene which promotes cell invasion and endows tumor cells stem cell capacity in nasopharyngeal carcinoma (NPC), but its correlation with clinicopathologic characteristics and patients' survival in NPC remain undefined. Methods: In this study, 158 cases of confirmed NPC were subjected to immunohistochemistry staining for evaluating endogenous expression. Kaplan-Meier method and log-rank test were used to estimate the survival rates. The relationship between ZNF488 and clinicopathological characteristics was statistically calculated by chi-squared test, univariate and multivariate analysis. In addition, adhesion assay, MTT and colony formation assays were performed for measuring adhesion and proliferation capacity. Cell cycle analysis via flow cytometry was conducted to explore cell cycle distribution. Western blot was used to detect pathway protein levels, and the pFAK (Y397) kit was used for focal adhesion kinase (FAK) activation. Results: We demonstrated that high expression of ZNF488 was significantly correlated with locoregional failure (P=0.018) and distant metastasis (P=0.001). Patients with high ZNF488 expression had poorer overall survival (P<0.001), loco-regional recurrence-free survival (P<0.001), distance metastasis-free survival (P<0.001) and progression-free survival (P<0.001) than those with low ZNF488 group. Multivariate analysis showed that ZNF488 expression was an independent prognostic indicator for predicting NPC patients' survival (HR, 3.314; 95% CI, 1.489-7.386; P=0.003). Additionally, ZNF488-induced collagen IV/FAK/AKT to enhance adhesion ability meanwhile led to the upregulation of Cyclin D1 to facilitate cell proliferation through promoting cell cycle progression and inhibition of apoptosis through caspase-independent way. Conclusion: These results reveal that ZNF488, as an independent prognostic indicator, promotes cell adhesion and proliferation through collagen IV/FAK/AKT/Cyclin D1 pathway in NPC.

Stabilizing electrochemical Li-O2 batteries with a metal-based cathode of PdNi on Ni nonwoven fabric.

The design of a nanoporous cathode for Li-O2 batteries that can achieve high chemical stability and superior electrochemical performance remains a formidable challenge. A novel approach for the fabrication of nanoengineered PdNi alloys directly coated onto Ni nonwoven fabric (PdNi/NiNF) obtained through electrospinning has been proposed. On the basis of the contributions of the porous structure, the prepared metal-based cathodes can exhibit high chemical and mechanical stabilities, high catalytic activity, and high conductivity. In this design, the major side reactions were excluded when compared with popularly used carbon cathodes, and excellent cycling stability (266 cycles) could be achieved. The proposed cathode exhibited a high discharge capacity of 15 700 mA h g-1 at 500 mA g-1, which was 5 times higher than those reported for carbon-free cathodes.

Selenoprotein SELENOK Enhances the Migration and Phagocytosis of Microglial Cells by Increasing the Cytosolic Free Ca2+ Level Resulted from the Up-Regulation of IP3R.

Enhancing the migration and phagocytosis of microglial cells is of great significance for the reducing of the risk of the neurodegenerative diseases, such as Alzheimer's disease (AD) and Parkinson's disease (PD). The effect of mouse selenoprotein K (mSELENOK) on the migration and phagocytosis of BV2 microglial cells and its mechanism were studied. The results showed that the over-expression of mSELENOK can increase the migratory and phagocytic abilities of the microglial cells, while the knockdown of mSELENOK can decrease the migratory and phagocytic abilities of the cells. The cytosolic free Ca2+ level and inositol trisphosphate receptor (IP3R) mRNA transcript and protein expression were also increased significantly as the consequence of the over-expression of mSELENOK in the microglial cells. On the contrary, the level of cytosolic free Ca2+ and the mRNA transcript and protein expression of IP3R in mSELENOK knockdown cells were decreased significantly. 2-aminoethoxydiphenyl borate (2-APB), an antagonist of IP3R, could prevent the increased migration, phagocytosis, and cytosolic free Ca2+ level of mSELENOK over-expressed microglial cells, and knockdown of IP3R3 could reduce the increased cytosolic Ca2+ level in mSELENOK over-expressed microglial cells. Further studies revealed that selenium supplement (Na2SeO3) can increase the expression of mSELENOK in microglial cells significantly. In summary, these data suggest that mSELENOK can increase cytosolic free Ca2+ level of microglial cells by up-regulating the expression of IP3R, thus enhancing the migration and phagocytosis of microglial cells. Our results indicated that mSELENOK is an important selenoprotein, which plays a role in trace element selenium's functions and can enhance the migration and phagocytosis of microglial cells.

Protective properties of Huperzine A through activation Nrf2/ARE-mediated transcriptional response in X-rays radiation-induced NIH3T3 cells.

Huperzine A (HupA), derived from Huperzia Serrata, has exhibited a variety of biological actions, in particular neuroprotective effect. However, the protective activities of HupA on murine embryonic fibroblast NIH3T3 cells after X-rays radiation have not been fully elucidated. Herein, HupA treatment dramatically promoted cell viability, abated a G0/G1 peak accumulation, and ameliorated increase of cell apoptosis in NIH3T3 cells after X-rays radiation. Simultaneously, HupA notably enhanced activities of anti-oxidant enzymes, inhibited activity of lipid peroxide, and efficiently eliminated production of reactive oxygen species in NIH3T3 cells after X-rays radiation. Dose-dependent increase of antioxidant genes by HupA were associated with up-regulated Nrf2 and down-regulated Keap-1 expression, which was confirmed by increasing nuclear accumulation, and inhibiting of degradation of Nrf2. Notably, augmented luciferase activity of ARE may explained Nrf2/ARE-mediated signaling pathways behind HupA protective properties. Moreover, expression of Nrf2 HupA-mediated was significant attenuated by AKT inhibitor (LY294002), p38 MAPK inhibitor (SB202190) and ERK inhibitor (PD98059). Besides, HupA-mediated cell viability, and ROS production were dramatically bated by LY294002, SB202190, and PD98059. Taken together, HupA effectively ameliorated X-rays radiation-induced damage Nrf2-ARE-mediated transcriptional response via activation AKT, p38, and ERK signaling in NIH3T3 cells.

Effectiveness of Cetuximab in Combination with Concurrent Chemoradiotherapy in Locoregionally Advanced Nasopharyngeal Carcinoma: A 1:2 Propensity Score-matched Analysis.

Background: This study aimed to compare concurrent chemoradiotherapy (CCRT) plus cetuximab (C) with CCRT alone in locoregionally advanced nasopharyngeal carcinoma(NPC). Methods: A total of 682 locoregionally advanced NPC patients who had undergone chemoradiotherapy with or without cetuximab were included. Propensity score-matching method was used to match patients. Progression-free survival (PFS), overall survival (OS), locoregional relapse-free survival (LRFS), and distant metastasis-free survival (DMFS) were compared between the two treatment arms. Results: After matching, 225 patients were identified for the analysis. Compared to CCRT, CCRT plus C was associated with significantly improved 3-year PFS (83.7% vs 71.9%, P = 0.036), LRFS (98.6% vs 90.2%, P = 0.034) but not OS (91.4% vs 85.4%, P = 0.117). Among patients with T4 and/or N3 category, CCRT plus C significantly prolonged 3-year PFS (81.0% vs 61.4%, P = 0.022) and increased 3-year OS (88.0% vs 77.9%, P = 0.086). No significant differences were observed between CCRT plus C and CCRT alone groups with regard to 3-year PFS, OS, LRFS and DMFS rates in stage III patients. Acute oral and oropharyngeal mucositis during radiotherapy were more common in the CCRT plus C than that in CCRT, but late toxicities were comparable. Conclusions: This study reveals that patients with locoregionally advanced NPC could benefit from the addition of cetuximab to CCRT, and this therapeutic gain mainly originated from T4 and/or N3 subgroup although suffering more acute moderate to severe toxicities.

Transition-metal-catalyst-free synthesis of anthranilic acid derivatives by transfer hydrogenative coupling of 2-nitroaryl methanols with alcohols/amines.

By using a transfer hydrogenative coupling strategy, we herein describe a new method for the efficient synthesis of anthranilic acid derivatives, a significantly important class of compounds with extensive applications in organic synthesis and the discovery of bioactive molecules, from 2-nitroaryl methanols and readily available alcohols/amines. The synthesis proceeds with the merits of no need for a transition metal catalyst, operational simplicity, broad substrate scope, good functional tolerance, and high step efficiency, which offers a useful alternative to access anthranilic acid derivatives.

Hydrogen-Transfer-Mediated α-Functionalization of 1,8-Naphthyridines by a Strategy Overcoming the Over-Hydrogenation Barrier.

A general catalytic hydrogen transfer-mediated α-functionalization of 1,8-naphthyridines is reported for the first time that benefits from a hydrogen transfer-mediated activation mode for non-activated pyridyl cores. The pyridyl α-site selectively couples with the C8-site of various tetrahydroquinolines (THQs) to afford novel α-functionalized tetrahydro 1,8-naphthyridines, a class of synthetically useful building blocks and potential candidates for the discovery of therapeutic and bio-active products. The utilization of THQs as inactive hydrogen donors (HDs) appears to be a key strategy to overcome the over-hydrogenation barrier and address the chemoselectivity issue. The developed chemistry features operational simplicity, readily available catalyst and good functional group tolerance, and offers a significant basis for further development of new protocols to directly transform or functionalize inert N-heterocycles.