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Achieving electrostatic control of quantum phases is at the frontier of condensed matter research. Recent investigations have revealed superconductivity tunable by electrostatic doping in twisted graphene heterostructures and in two-dimensional (2D) semimetals such as WTe$_2$. Some of these systems have a polar crystal structure that gives rise to ferroelectricity, in which the interlayer polarization exhibits bistability driven by external electric fields. Here we show that bilayer $T_d$-MoTe$_2$ simultaneously exhibits ferroelectric switching and superconductivity. Remarkably, a field-driven, first-order superconductor-to-normal transition is observed at its ferroelectric transition. Bilayer $T_d$-MoTe$_2$ also has a maximum in its superconducting transition temperature ($T_\textrm{c}$) as a function of carrier density and temperature, allowing independent control of the superconducting state as a function of both doping and polarization. We find that the maximum $T_\textrm{c}$ is concomitant with compensated electron and hole carrier densities and vanishes when one of the Fermi pockets disappears with doping. We argue that this unusual polarization-sensitive 2D superconductor is driven by an interband pairing interaction associated with nearly nested electron and hole Fermi pockets.

Achieving electrostatic control of quantum phases is at the frontier of condensed matter research. Recent investigations have revealed superconductivity tunable by electrostatic doping in twisted graphene heterostructures and in two-dimensional semimetals such as WTe

The responses of soil denitrifiers to inorganic and organic mixed fertilization in paddies have not been well evaluated. The abundance and diversity of nirS- and nirK-type denitrifiers in paddies a...

The diversity seen in the mode of pharmacology and the numerous glutamate receptor subtypes have previously complicated drug development efforts. Nonetheless, recent clinical trials of drug candidates that accommodate the glutamatergic intricate pharmacology have yielded encouraging results. Target engagement is an important requirement for the advancement of central nervous system drug candidates into clinical trial. Positron emission tomography (PET) tracer technology has the unique ability to give the direct insight into the relationship between the level of receptor occupancy and the administered dose, thus establishing a direct link between the level of target exposure and the drug efficacy in human. This review is focused on the advancement of mGlu5 , mGlu 1 , and mGlu 2 receptor-related PET tracer technology: PET tracer development strategies, PET tracer selection in receptor occupancy studies, the scopes and limitations to use PET to measure receptor occupancy for the drug candidates with different pharmacology, and how to use the measurements of receptor occupancy as a translational biomarker for decision-making in an innovative drug development program.

To achieve relatively high, stable corn (Zea mays L.) yield and water productivity (WPc) in aeolian sandy soil in the corn belt of northeast China (CBNC), a 4-year field experiment was conducted from 2017 to 2020 to evaluate the effects of irrigation on yield and WPc. The field experiment included four treatments: no irrigation (NI), single irrigation (SI), two irrigation events (TI), and full irrigation (FI) at the Lishu Experimental Station, Jilin Province, China. The results showed that, the TI and FI treatments improved the relative soil water content (RSWC) of the corn root zone and the aboveground biomass relative to the NI and SI treatments. The corn yield in the SI, TI, and FI treatments was 16–187%, 19–438%, and 17–409% greater than that of the NI treatment, respectively. The coefficient of variation of yield from 2017 to 2020 in the NI, SI, TI, and FI treatments were 47%, 23%, 4%, and 2%, respectively. The TI and FI treatments increased evapotranspiration relative to the NI and SI treatments. The TI and FI treatments increased the WPc by 10–396% and 24–324% compared with the NI treatment. No difference in WPc was observed between the TI and FI treatments. The irrigation water productivity (WPI) of the TI treatment was 35% and 46% higher than that of the FI treatment in 2017 and 2020, respectively, while no difference was observed in 2018 and 2019. Therefore, the TI treatment is recommended to improve the yield and WPc of corn in the aeolian sandy soil of the CBNC.

Traditional cooling systems consume tremendous amounts of energy and thus aggravate the greenhouse effect1,2. Passive radiative cooling, dissipating an object’s heat through an atmospheric transparency window (8–13 μm) to outer space without any energy consumption, has attracted much attention3–9. The unique feature of radiative cooling lies in the high emissivity in the atmospheric transparency window through which heat can be dissipated to the universe. Therefore, for achieving high cooling performance, the design and fabrication of selective emitters, with emission strongly dominant in the transparency window, is of essential importance, as such spectral selection suppresses parasitic absorption from the surrounding thermal radiation. Recently, various materials and structures with tailored spectrum responses have been investigated to achieve the effect of daytime radiative cooling6–8,10–15. However, most of the radiative cooling materials reported possess broad-band absorption/emission covering the whole mid-infrared wavelength11–15. Here we demonstrate that a hierarchically designed polymer nanofibre-based film, produced by a scalable electrostatic spinning process, enables selective mid-infrared emission, effective sunlight reflection and therefore excellent all-day radiative cooling performance. Specifically, the C–O–C (1,260–1,110 cm−1) and C–OH (1,239–1,030 cm−1) bonding endows the selective emissivity of 78% in 8–13 μm wavelength range, and the design of nanofibres with a controlled diameter allows for a high reflectivity of 96.3% in 0.3–2.5 μm wavelength range. As a result, we observe ~3 °C cooling improvement of this selective thermal emitter as compared to that of a non-selective emitter at night, and 5 °C sub-ambient cooling under sunlight. The impact of this hierarchically designed selective thermal emitter on alleviating global warming and temperature regulating an Earth-like planet is also analysed, with a significant advantage demonstrated. With its excellent cooling performance and a scalable process, this hierarchically designed selective thermal emitter opens a new pathway towards large-scale applications of all-day radiative cooling materials. A hierarchically designed polymer nanofibre-based film produced by a scalable electrospinning process enables selective mid-infrared emission and effective sunlight reflection, and thus realizes an excellent all-day radiative cooling performance.

The responses of soil denitrifiers to inorganic and organic mixed fertilization in paddies have not been well evaluated. The abundance and diversity of nirS- and nirK-type denitrifiers in paddies after 30-year fertilization were estimated using quantitative PCR and Illumina MiSeq sequencing. The nirS gene abundance was two orders of magnitude higher than the nirK gene and both were reduced by fertilization. The high manure addition (NPK + 60% OM) decreased nirK gene abundance by 32.7% compared to inorganic fertilization alone (NPK) and decreased its community Chao1 index by 30.2% compared to unfertilized control (CK). Fertilization significantly changed the proportion of dominant (mean proportion > 1%) operational taxonomic units (OTUs) of both denitrifiers. Fertilization increased the proportion of OTUs belonged to cluster III (48.7–97.3%) of the nirS-type denitrifiers compared to CK. NPK + 60% OM increased that belonged to cluster II (48.0%) compared to the low manure addition (NPK + 30% OM). Total nitrogen and organic carbon correlated significantly with the abundance, diversity and community structure of the nirK-type denitrifiers, while they solely correlated with the nirS-type denitrifier community structure. Our results demonstrate that abundance and diversity of the nirK-type denitrifiers are more, while the community structure is less, sensitive to inorganic and organic mixed fertilization than the nirS-type in paddy soils.

The advanced artificial intelligence technologies have promoted the development of other industries. As a combination of AI technologies and art, intelligent design has become a research hotspot in recent years. Intelligent design uses computer to simulate human thinking activities with AI technologies, enabling the computers to undertake more complex design tasks in a better way. At the same time, reinforcement learning plays an increasingly important role in many fields, such as system control, game theory, computer network, decision making, etc. In this work, an intelligent design system based on the reinforcement learning algorithm was proposed, and corresponding reward rules were developed according to the design principles. The system can help the designer to generate the optimal scheme automatically, which can be extended and applied to find the best scheme in many problems, including interior design, daily schedule, resource arrangement, etc. Our demo shows that the system can offer excellent design scheme according to pre-set reward rules, and reduce workload of related designers.

The proper choice of a planting pattern is a key issue in the Corn Belt of Northeast China (CBNC) for national grain security and increasing the incomes of farmers. Field experiments were conducted from 2014 to 2016 in Lishu County, Jilin Province, China in order to evaluate alfalfa intercropping within the context of a uniform planting density of corn. The four treatments included corn monoculture (nC) as the control, 3-row corn intercropping with 3-row alfalfa cultivation (3C/3A), 3-row corn intercropping with 5-row alfalfa cultivation (3C/5A), and alfalfa monoculture (nA). Corn–alfalfa intercropping did not affect soil moisture in 2014. In 2015, the relative soil water content of the 3C/5A treatment was lower than that of the nC treatment, and the relative soil water content of the 3C/3A treatment was higher than that of the nC treatment. Biomass and yield under the 3C/5A treatment were greater than those under the nC treatment in a normal year (2014) and a wet year (2016). Biomass water use efficiency and net revenue under the 3C/5A treatment were similar with those under the nC treatment. Net revenue of the 3C/5A treatment was 14% higher than that of the nC treatment in a dry year (2015). Biomass, biomass water use efficiency, and net revenue under the 3C/5A treatment were higher than those under the 3C/3A treatment. The 3C/5A treatment was an effective planting pattern over the 3 years, with a total net revenue 443 USD ha−1 higher than that of the nC treatment. The nA treatment’s biomass and biomass water use efficiency were less than those of the nC treatment, but its economic benefit was highest among all treatments, with a total net revenue 2510 USD ha−1 higher than that of the nC treatment. Therefore, planting alfalfa as a monoculture or as part of a 3C/5A intercropping system is recommended to improve soil fertility and the development of animal husbandry while financially benefiting farmers.

Runoff loss and soil erosion are the main factors threatening grain production in the corn belt of northeast China (CBNC) and are closely related to the planting pattern, row direction, and practice of straw mulching. A 4-year (2017–2020) field experiment was conducted under natural rainfall conditions from 2017 to 2020 to ascertain the effects of the planting pattern, including continuous corn (C), perennial alfalfa (A), and soybean-corn rotation (S-C); row direction including parallel slope (PS) and cross slope (CS); and practice of straw mulching (marked by the subscript SM) on runoff and soil erosion from sloped farmland in the CBNC. Runoff depth and the amount of soil loss under continuous corn with parallel-slope cultivation (PSC) were higher than those of alfalfa with parallel-slope cultivation (PSA) and soybean-corn rotation with parallel-slope cultivation (PSS-PSC) during 2017–2020. Cross-slope planting (CSA, CSC, and CSS-CSC) reduced runoff loss by 7.8–23.3% and the amount of soil erosion by 15.9–73.7% when compared to parallel-slope planting (PSA, PSC, and PSS-PSC). The CSA treatment generated the least runoff depth and soil erosion amount among CSA, CSC, and CSS-CSC. Straw mulching (PSCSM and PSSSM-PSCSM) decreased runoff by 82.6–85.5% and reduced the amount of soil erosion by 87.9–91.5% relative to not using straw mulching treatments (PSC and PSS-PSC). Therefore, cross-slope cultivation and straw mulching can significantly reduce surface runoff and soil erosion on slope farmland. The CSA treatment and the practice of straw mulching were recommended for soil and water conservation in the CBNC.

An efficient asymmetric synthesis of MDM2 antagonist RG7388 is reported. The highly functionalized chiral pyrrolidine carboxamide was assembled via a Cu(OAc)2/(R)-BINAP catalyzed asymmetric [3 + 2] cycloaddition, which gave the exo and endo adducts in a ratio of 10:1, with high enantiomeric excess for the exo isomer. A one-pot hydrolysis and retro-Mannich/Mannich isomerization of the cycloaddition adducts in the presence of aqueous sodium hydroxide afforded RG7388 in high chemical and enantiomeric purities and 69% overall yield.

Summary The cosmic-ray neutron sensor (CRNS), which estimates field scale soil water content, bridges the gap between point measurement and remote sensing. The accuracy of CRNS measurements, however, is affected by additional hydrogen pools (e.g., vegetation, snow, and rainfall interception). The objectives of this study are to: (i) evaluate the accuracy of CRNS estimates in a farmland system using depth and horizontal weighted point measurements, (ii) introduce a novel method for estimating the amounts of hydrogen from biomass and snow cover in CRNS data, and (iii) propose a simple approach for correcting the influences of aboveground hydrogen pool (expressed as aboveground water equivalent, AWE) on CRNS measurements. A field experiment was conducted in northeast China to compare soil water content results from CRNS to in-situ data with time domain reflectometry (TDR) and neutron probe (NP) in the 0–40 cm soil layers. The biomass water equivalent (BWE) and snow water equivalent (SWE) were observed to have separate linear relationships with the thermal/fast neutron ratio, and the dynamics of BWE and SWE were estimated correctly in the crop seasons and snow-covered seasons, respectively. A simple approach, which considered the AWE, AWE at calibration, and the effective measurement depth of CRNS, was introduced to correct the errors caused by BWE and SWE. After correction, the correlation coefficients between soil water contents determined by CRNS and TDR were 0.79 and 0.77 during the 2014 and 2015 crop seasons, respectively, and CRNS measurements had RMSEs of 0.028, 0.030, and 0.039 m 3 m −3 in the 2014 and 2015 crop seasons and the snow-covered seasons, respectively. The experimental results also indicated that the accuracies of CRNS estimated BWE and SWE were affected by the distributions of aboveground hydrogen pools, which were related to the height of the CRNS device above ground surface.

Decreasing the corn ( Zea mays L.) gap between the potential yield and farm yield and reducing the risk of grain yield of drought are very important for corn production in the Corn Belt of Northeast China (CBNC). To achieve a high and stable corn yield, the effects of supplementary irrigation on yield, water use efficiency (WUE) and irrigation water use efficiency (IWUE) were studied using a modelling approach. The Root Zone Water Quality Model 2 was parameterized and evaluated using two years of experimental data in aeolian sandy soil and black soil. The evaluated model was then used to investigate responses to various irrigation strategies (rainfed, full irrigation and 12 single irrigation scenarios) using long-term weather data from 1980 to 2012. Full irrigation guarantees a high and stable corn grain yield (12.92 Mg ha −1 and has a coefficient of variation (CV) of 14.8% in aeolian sandy soil; 12.30 kg Ma −1 and CV of 11.1% in black soil), but has a low water use efficiency (19.92 and 21.81 kg ha −1 mm −1 ) and a low irrigation water use efficiency (10.01 and 11.03 kg ha −1 mm −1 ). A single irrigation can increase corn yields by 3–35% for aeolian sandy soil and 5–35% for black soil over different irrigation dates compared with no irrigation. The most suitable single irrigation date was during late June to early July for aeolian sandy soil (yield = 10.73 Mg ha −1 and WUE = 27.94 kg ha −1 mm −1 ) and early to mid-July for black soil (yield = 11.20 Mg ha −1 and WUE = 27.70 kg ha −1 mm −1 ). The lowest yield risk of falling short of the yield goal of 8, 9, and 10 Mg ha −1 were 9.1%, 18.2%, and 33.33% in aeolian sandy soil and 3.0%, 15.25, and 21.2% in black soil when an optimized single irrigation was applied in late June or early July, respectively. Therefore, an optimized single irrigation should be applied in late June to early July with the irrigation amount to refill soil water storage of root zone to field capacity in CBNC.

Understanding how soil type in the Corn Belt of Northeast China affects both the potential yield of a rainfed crop [Yp(r)] and the yield gap [YG(r)] between Yp(r) and the water non-limiting potential yield (Yp) is essential for enhancing corn (Zea mays L.) production and identifying critical irrigation windows for different soil types. The Root Zone Water Quality Model 2 (RZWQM2) was calibrated and validated based on 2 yr of experimental data and then used to estimate Yp and Yp(r) along with YG(r) in aeolian sandy soil vs. black soil using the same weather data from 1980 to 2012. The values for Yp were the same for both soil types, and the mean Yp was 11.299 Mg ha–¹ (CV of 15.6%) during the 33-yr simulation period. The mean Yp(r) was lower in the aeolian sandy soil (7.628 Mg ha–¹, CV of 39.8%) than in the black soil (8.893 Mg ha–¹, CV of 34.5%). The mean YG(r) was 3.672 Mg ha–¹ in the aeolian sandy soil and 2.406 Mg ha–¹ in the black soil. Values for Yp(r) were positively correlated with precipitation in June and July in the aeolian sandy soil and in July in the black soil. The YG(r) was negatively correlated with precipitation in June and July in both soils. Therefore, soil type affected Yp(r) and YG(r) through the soil water condition under the same weather conditions. The critical irrigation window to decrease YG(r) is in June and July for aeolian sandy soils and in July for black soils.