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More than half of current coal power capacity is in China. A key strategy for meeting China’s 2060 carbon neutrality goal and the global 1.5 °C climate goal is to rapidly shift away from unabated coal use. Here we detail how to structure a high-ambition coal phaseout in China while balancing multiple national needs. We evaluate the 1037 currently operating coal plants based on comprehensive technical, economic and environmental criteria and develop a metric for prioritizing plants for early retirement. We find that 18% of plants consistently score poorly across all three criteria and are thus low-hanging fruits for rapid retirement. We develop plant-by-plant phaseout strategies for each province by combining our retirement algorithm with an integrated assessment model. With rapid retirement of the low-hanging fruits, other existing plants can operate with a 20- or 30-year minimum lifetime and gradually reduced utilization to achieve the 1.5 °C or well-below 2 °C climate goals, respectively, with complete phaseout by 2045 and 2055.

The relationship between detection threshold of inspiratory resistive loads and the peaks of the respiratory-related evoked potential (RREP) is unknown. It was hypothesized that the short-latency and long-latency peaks of the RREP would only be elicited by inspiratory loads that exceeded the detection threshold. The detection threshold for inspiratory resistive loads was measured in healthy subjects with inspiratory-interruption or onset load presentations. In a separate protocol, the RREPs were recorded with resistive loads that spanned the detection threshold. The loads were presented in stimulus attend and ignore sessions. Onset and interruption load presentations had the same resistive load detection threshold. The P(1), N(f), and N(1) peaks of the RREP were observed with loads that exceeded the detection threshold in both attend and ignore conditions. The P(300) was present with loads that exceeded the detection threshold only in the attend condition. No RREP components were elicited with subthreshold loads. The P(1), N(f), and P(300) amplitudes varied with resistive load magnitude. The results support the hypothesis that there is a resistive load threshold for eliciting the RREPs. The amplitude of the RREP peaks vary as a function of load magnitude. The cognitive P(300) RREP peak is present only for detectable loads and when the subject attends to the stimulus. The absence of the RREP with loads below the detection threshold and the presence of the RREP elicited by suprathreshold loads are consistent with the gating of these neural measures of respiratory mechanosensory information processing.

Activation of neuronal ATP-sensitive potassium (K(ATP)) channels is an important mechanism that protects neurons and conserves neural function during hypoxia. We investigated hypoxia (bath gassed with 95% N(2)-5% CO(2) vs. 95% O(2)-5% CO(2) in control)-induced changes in K(ATP) current in second-order neurons of peripheral chemoreceptors in the nucleus of the solitary tract (NTS). Hypoxia-induced K(ATP) currents were compared between normoxic (Norm) rats and rats exposed to 1 wk of either chronic sustained hypoxia (CSH) or chronic intermittent hypoxia (CIH). Whole cell recordings of NTS second-order neurons identified after 4-(4-(dihexadecylamino)styryl)-N-methylpyridinium iodide (DiA) labeling of the carotid bodies were obtained in a brain stem slice. In Norm cells (n = 9), hypoxia (3 min) induced an outward current of 12.7 +/- 1.1 pA with a reversal potential of -73 +/- 2 mV. This current was completely blocked by the K(ATP) channel blocker tolbutamide (100 muM). Bath application of the K(ATP) channel opener diazoxide (200 muM, 3 min) evoked an outward current of 21.8 +/- 5.8 pA (n = 6). Hypoxia elicited a significantly smaller outward current in both CSH (5.9 +/- 1.4 pA, n = 11; P < 0.01) and CIH (6.8 +/- 1.7 pA, n = 6; P < 0.05) neurons. Diazoxide elicited a significantly smaller outward current in CSH (3.9 +/- 1.0 pA, n = 5; P < 0.05) and CIH (2.9 +/- 0.9 pA, n = 3; P < 0.05) neurons. Western blot analysis showed reduced levels of K(ATP) potassium channel subunits Kir6.1 and Kir6.2 in the NTS from CSH and CIH rats. These results suggest that hypoxia activates K(ATP) channels in NTS neurons receiving monosynaptic chemoreceptor afferent inputs. Chronic exposure to either sustained or intermittent hypoxia reduces K(ATP) channel function in NTS neurons. This may represent a neuronal adaptation that preserves neuronal excitability in crucial relay neurons in peripheral chemoreflex pathways.

Background: Coronavirus disease 2019 (COVID-19) is primarily a respiratory disease that has become a global pandemic. Close contact plays an important role in infection spread, while fomite may also be a possible transmission route. Research during the COVID-19 pandemic has identified long-range airborne transmission as one of the important transmission routes although lack solid evidence. Methods: We examined video data related to a restaurant associated COVID-19 outbreak in Guangzhou. We observed more than 40,000 surface touches and 13,000 episodes of close contacts in the restaurant during the entire lunch duration. These data allowed us to analyse infection risk via both the fomite and close contact routes. Results: There is no significant correlation between the infection risk via both fomite and close contact routes among those who were not family members of the index case. We can thus rule out virus transmission via fomite contact and interpersonal close contact routes in the Guangzhou restaurant outbreak. The absence of a fomite route agrees with the COVID-19 literature. Conclusions: These results provide indirect evidence for the long-range airborne route dominating SARS-CoV-2 transmission in the restaurant. We note that the restaurant was poorly ventilated, allowing for increasing airborne SARS-CoV-2 concentration.

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This study measured the particle concentrations with an aerodynamic diameter smaller than 2.5 μm (PM2.5), nitrogen dioxide (NO2), and relative humidity (RH) at five subway metro stations in Suzhou's subway system (Lines 1 and 2).

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