Global warming and shifts in cropping systems together reduce China's rice production

Climate warming is widely expected to affect rice yields, but results are equivocal and variation in rice cropping systems and climatic conditions complicates country-scale yield assessments. Here we show, through meta–a- nalysis of field warming experiments, that yield responses to warming differ strongly between China's rice cropping systems. Whereas warming increases yields in “single rice” systems, it decreases yields in “middle rice” systems and has contrasting effects for early and late rice in “double rice” systems. We further show that the contribution of these cropping systems to China's total rice production has shifted dramatically over recent decades. We estimate that if the present structure of rice cropping systems persists, warming will reduce China's total rice production by 5.0% in 2060. However, if the recent decline in the area of double rice systems con- tinues, China's rice production may decrease by 13.5%. Our results underline the need for maintaining the current area of China's “double rice” cropping system and for technological innovations in multiple rice cropping systems to ensure food security in a warming climate

Two Transient Quasi-periodic Oscillations in γ-Ray Emission from the Blazar S4 0954+658

In this work, we report periodicity search analyses in the gamma-ray light curve of the blazar S4 0954+658 in monitoring undertaken by the Fermi Large Area Telescope. Four analytical methods and a tool are adopted to detect any periodic flux modulation and corresponding significance level, revealing: (i) a quasi-periodic oscillation (QPO) of 66 days with a significance level of >5 σ spanning over 600 days from 2015 to 2016 (MJD 57,145–57,745), resulting in continuous observation of nine cycles, which is one of the longest cycles discerned in blazar gamma-ray light curves; (ii) a possible QPO of 210 days at a moderate significance of ∼3.5 σ , which lasted for over 880 days from 2020 to 2022 (MJD 59,035–59,915) and for four cycles. In addition, we discuss several physical models to explain the origin of the two transient QPOs and conclude that a geometrical scenario involving a plasma blob moving helically inside the jet can explain the timescale of the QPO

Experimental Study of the Effect of Intake Oxygen Concentration on Engine Combustion Process and Hydrocarbon Emissions with N-Butanol-Diesel Blended Fuel

This paper summarizes a study based on a modified, light, single-cylinder diesel engine and the effects of the physicochemical properties for n-butanol-diesel blended fuel on the combustion process and hydrocarbon (HC) emissions in the intake at a medium speed and moderate load in, an oxygen-rich environment (Coxy = 20.9–16%), an oxygen-medium environment (Coxy = 16–12%), and an oxygen-poor environment (Coxy = 12–9%). The results show that the ignition delay period is the main factor affecting the combustion process and it has a decisive influence on HC emissions. In an oxygen-medium environment, combustion duration affected by the cetane number is the main reason for the difference in HC emissions between neat diesel fuel (B00) and diesel/n-butanol blended fuel (B20), and its influence increases as the intake oxygen concentration decreases. In an oxygen-poor environment, in-cylinder combustion temperature affected by the latent heat of vaporization is the main reason for the difference in HC emissions between B00 and B20 fuels, and its influence increases as the intake oxygen concentration decreases. By comparing B20 fuel with diesel/n-butanol/2-ethylhexyl nitrate blended fuel (B20 + EHN), the difference in the ignition delay period caused by the difference in the cetane number is the main reason for the difference in HC emissions between B20 and B20 + EHN fuels in oxygen-poor environment, and the effect of this influencing factor gradually increases as the intake oxygen concentration decreases

Impacts of nighttime post-anthesis warming on rice productivity and grain quality in East China

The impacts of nighttime post-anthesis warming on rice productivity and grain quality in East China were evaluated for two cultivars, II You 128, an indica rice, and Wuyunjing 7, a japonica rice. Warming by 3.0 °C stimulated the nighttime respiration rate and decreased the photosynthesis rate, resulting in significant decreases of 21.2% and 24.9% in aboveground biomass accumulation for II You 128 and Wuyunjing 7, respectively. Warming significantly reduced the rates of seed setting and grain filling, especially of inferior kernels (those lower in panicles), while the filling rate of superior kernels remained almost unchanged. As a result, 1000-grain weight and grain yield were respectively 3.7% and 30.0% lower for II You 128 and 12.8% and 34.3% for Wuyunjing 7 in warmed plots than in the unwarmed control. Nighttime warming also significantly reduced the grain milling and appearance quality of both varieties. More negative effects of warming on inferior than on superior kernels were found. The above results have important implications for rice variety cultivation in East China

A platinum@polymer-catechol nanobraker enables radio-immunotherapy for crippling melanoma tumorigenesis, angiogenesis, and radioresistance

Malignant melanoma cell-intrinsic PD-1:PD-L1 interaction thrusts tumorigenesis, angiogenesis, and radioresistance via mTOR hyperactivation to aggravate circumjacent aggression. Interdicting melanoma intrinsic growth signals, including the blockade of PD-L1 and mTOR signaling concurrently, cooperative with radiotherapy may provide a vigorous repertoire to alleviate the tumor encumbrance. Thence, we design a three-pronged platinum@polymer-catechol nanobraker to deliver mTOR inhibitor TAK228 and anti-PD-L1 antibody (aPD-L1) for impeding the melanoma-PD-1-driven aggression and maximizing the melanoma eradication. The aPD-L1 collaborated with TAK228 restrains melanoma cell-intrinsic PD-1: PD-L1 tumorigenic interaction via blocking melanoma-PD-L1 ligand and the melanoma-PD-1 receptor-driven mTOR signaling; corresponding downregulation of mTOR downstream protumorigenic cellular MYC and proangiogenic hypoxia-inducible factor 1-alpha is conducive to preventing tumorigenesis and angiogenesis, respectively. Further, high-Z metal platinum sensitizing TAK228-enhanced radiotherapy confers the nanobraker on remarkable tumoricidal efficacy. Hereto, the customized three-pronged nanobrakers efficiently suppress melanoma tumorigenesis and angiogenesis concomitant with the amplification of radiotherapeutic efficacy. Such an ingenious tactic may provide substantial benefits to clinical melanoma patients

Heterodimerization of the kappa opioid receptor and neurotensin receptor 1 contributes to a novel β-arrestin-2–biased pathway

Together with its endogenous ligands (dynorphin), the kappa opioid receptor (KOR) plays an important role in modulating various physiological and pharmacological responses, with a classical G protein–coupled pathway mediating analgesia and non-G protein–dependent pathway, especially the β-arrestin–dependent pathway, eliciting side effects of dysphoria, aversion, drug-seeking in addicts, or even relapse to addiction. Although mounting evidence has verified a functional overlap between dynorphin/KOR and neurotensin/neurotensin receptor 1 (NTSR1) systems, little is known about direct interaction between the two receptors. Here, we showed that KOR and NTSR1 form a heterodimer that functions as a novel pharmacological entity, and this heterodimer, in turn, brings about a switch in KOR-mediated signal transduction, from G protein–dependent to β-arrestin-2–dependent. This was simultaneously verified by analyzing a KOR mutant (196th residue) that lost the ability to dimerize with NTSR1. We also found that dual occupancy of the heterodimer forced the β-arrestin-2–dependent pathway back into Gi protein–dependent signaling, according to KOR activation. These data provide new insights into the interaction between KOR and NTSR1, and the newly discovered role of NTSR1 acting as a switch between G protein– and β-arrestin–dependent pathways of KOR also suggests a new approach for utilizing pathologically elevated dynorphin/KOR system into full play for its analgesic effect with limited side effects

Isolation and Characterization of <i>SPOTTED LEAF42</i> Encoding a Porphobilinogen Deaminase in Rice

The formation and development of chloroplasts play a vital role in the breeding of high-yield rice (Oryza sativa L.). Porphobilinogen deaminases (PBGDs) act in the early stage of chlorophyll and heme biosynthesis. However, the role of PBGDs in chloroplast development and chlorophyll production remains elusive in rice. Here, we identified the spotted leaf 42 (spl42) mutant, which exhibited a reddish-brown spotted leaf phenotype. The mutant showed a significantly lower chlorophyll content, abnormal thylakoid morphology, and elevated activities of reactive oxygen species (ROS)-scavenging enzymes. Consistently, multiple genes related to chloroplast development and chlorophyll biosynthesis were significantly down-regulated, whereas many genes involved in leaf senescence, ROS production, and defense responses were upregulated in the spl42 mutant. Map-based cloning revealed that SPL42 encodes a PBGD. A C-to-T base substitution occurred in spl42, resulting in an amino acid change and significantly reduced PBGD enzyme activity. SPL42 targets to the chloroplast and interacts with the multiple organelle RNA editing factors (MORFs) OsMORF8-1 and OsMORF8-2 to affect RNA editing. The identification and characterization of spl42 helps in elucidating the molecular mechanisms associated with chlorophyll synthesis and RNA editing in rice

Data S1

Genes differentially expressed in wild type and wsl5

Climatic Warming Increases Winter Wheat Yield but Reduces Grain Nitrogen Concentration in East China

<div><p>Climatic warming is often predicted to reduce wheat yield and grain quality in China. However, direct evidence is still lacking. We conducted a three-year experiment with a Free Air Temperature Increase (FATI) facility to examine the responses of winter wheat growth and plant N accumulation to a moderate temperature increase of 1.5°C predicted to prevail by 2050 in East China. Three warming treatments (AW: all-day warming; DW: daytime warming; NW: nighttime warming) were applied for an entire growth period. Consistent warming effects on wheat plant were recorded across the experimental years. An increase of ca. 1.5°C in daily, daytime and nighttime mean temperatures shortened the length of pre-anthesis period averagely by 12.7, 8.3 and 10.7 d (<i>P</i><0.05), respectively, but had no significant impact on the length of the post-anthesis period. Warming did not significantly alter the aboveground biomass production, but the grain yield was 16.3, 18.1 and 19.6% (<i>P</i><0.05) higher in the AW, DW and NW plots than the non-warmed plot, respectively. Warming also significantly increased plant N uptake and total biomass N accumulation. However, warming significantly reduced grain N concentrations while increased N concentrations in the leaves and stems. Together, our results demonstrate differential impacts of warming on the depositions of grain starch and protein, highlighting the needs to further understand the mechanisms that underlie warming impacts on plant C and N metabolism in wheat.</p> </div