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The Cu(I)-MOF catalyst was applied to the selective hydrogenation of CO2 to ethanol in a continuous-flow DBD plasma reactor. At an ambient condition, as high as 41.2% CO2 was converted to ethanol (selectivity up to 62.9%).

The yak is an agricultural animal with strong disease resistance in Qinghai-Tibet Plateau. Immune organs are directly involved in the body's immune response and protect it from external aggression. In this study, we characterized and evaluated the main markers of interleukin (IL)-1β, IL-17a, hypoxia inducer factor-1 (HIF-1)α, and heat shock protein 90 (HSP90) in the lymph nodes, spleen, thymus, and hemal nodes of adult yaks using network informatics, molecular cloning, immunohistochemistry, real-time quantitative polymerase chain reaction (RT-qPCR), and western blotting. We first cloned the IL-1β and IL-17a mRNA of yaks. A significant feature was the higher IL-1β and IL-17a expression in the lymph nodes than in the spleen, hemal nodes, and thymus. Immunohistochemistry and immunofluorescence revealed that IL-1β and IL-17a cells were mainly located in the paracortex area of the lymph nodes and the T-cell-dependent area in the hemal nodes and spleen. Several HIF-1α proteins were detected in the cortex of the hemal nodes mantle, while HSP90 was detected in the lymphoid nodules of the hemal nodes and lymph nodes. This study sheds light on the relationship between the morphology and function of these organs and provides an important reference for studies on the participation of yak immune organs in immune responses.

Infantile epileptic spasms syndrome (IESS) is the most common type of severe epilepsy in infants. However, etiological frequency and optimized therapy, particularly corticosteroid regimen and dose, remain unknown.An ambispective study of an IESS-diagnosed cohort was conducted. Etiologies were evaluated based on the 2017 International League Against Epilepsy classification system. Patients received intravenous dexamethasone or methylprednisolone for 3-5 consecutive days, followed by usual-dose (2 mg/kg/d) oral prednisone for 60-90 days with tapering doses for 1-2 months or high-dose (4 mg/kg/d) oral prednisone for 9-11 days with tapering doses for 2-4 weeks. Treatment responses were compared between the usual and high-dose prednisone groups after propensity score matching. Correlation analysis between treatment responses and underlying etiology was performed.Of the 441 included participants, 218 (49.4%) cases had proven etiologies. The most common etiology of IESS was acquired-structural (23.6%), followed by genetic (15.4%) and congenital-structural (7.0%). Hypoxic-ischemic encephalopathy (55, 52.8%) was the most common acquired-structural etiology. Among the 242 patients administered corticosteroids, 95 received usual-dose oral prednisone and 147 received high-dose oral prednisone. After propensity score matching, 54 patients were included in the usual-dose and high-dose groups, respectively, and treatment effectiveness was compared. There were no significant differences in seizure freedom at days 13-14 (55.6% vs. 51.9%, p = 0.700) and continued seizure freedom between days 14-42 (29.6% vs. 38.9%, p = 0.311) post corticosteroid administration between the usual- and high-dose prednisone groups. The proportion of children achieving seizure cessation at days 13-14 (χIESS etiology was primarily related to structural causes. Clinical response in short-term follow-up was independent of prednisone dosage and underlying etiology. Better EEG responses may occur in patients with unknown etiology.

On account of their inherent reactive properties, radical reactions play an important role in organic syntheses. The booming photochemistry provides a feasible approach to trigger the generation of radical intermediates in organic reaction processes. Thus, developing effective photocatalysts becomes the key step in radical reactions. In this work, the triphenylamine moiety with photoactivity is successfully embedded in a highly porous and stable metal-organic framework (MOF), and the obtained MOF, namely, Zr-TCA, naturally displays a photoactive property derived from the triphenylamine-based ligand. In photocatalytic studies, the triphenylamine-based Zr-TCA not only exhibits a high catalytic activity on the aerobic oxidation of sulfides via the generation of the superoxide radical anion (O2•-) under light irradiation but also shows good efficiency in the trifluoromethylation of arenes and heteroarenes by the formation of the trifluoromethyl radical (CF3•) as an intermediate. Moreover, the high performance of Zr-TCA can be well maintained over a wide range of substrates in these radical reactions, and the recycled Zr-TCA still retains its excellent photocatalytic activity. The high recyclability and catalytic efficiency to various substrates make the constructed triphenylamine-based Zr-TCA a promising photocatalyst in diverse radical reactions. Ministry of Education (MOE) This work was supported by the “Qilu Young Talent Scholar” Program of Shandong University and the Ministry of Education Singapore under its Academic Research Funds (RG3/21 and MOET2EP10120-0003).

Disruption remains to be a serious threat to large tokamaks like ITER. The injection speed of disruption mitigation systems (DMS) driven by high pressure gas is limited by the sound speed of the propellent gas. When extrapolating to ITER-like tokamaks, long overall reaction duration and shallow penetration depth due to low injection speed make it stricter for Plasma Control System to predict the impending disruptions. Some disruptions with a short warning time may be unavoidable. Thus, a fast time response and high injection speed DMS is essential for large scale devices. Electromagnetic Pellet-Injection (EMPI) system is a novel massive material injection system aiming to provide rapid and effective disruption mitigation. Based on railgun concept, EMPI can accelerate the payload to over 1000 m/s and shorten the overall reaction time to a few milliseconds. To verify the injection ability and stability of the EMPI, the prototype injector EMPI-1 has been designed and assembled. The preliminary test has been carried out using a 5.9 g armature to propel a dummy pellet and the results suggest that the EMPI configuration has a great potential to be the DMS of the large scale fusion devices.

A hetero-bichromophore thermally activated delayed fluorescence (TADF) emitter named BOQAO was designed and synthesized, which consists of two multi-resonance TADF (MR-TADF) cores, tBuBO and tBuQAO.

The color purity of the pixels is an essential indicator in organic light-emitting diode (OLED) commercial displays.

An analytical method of simultaneous detection of ten insecticide residues in honey and pollen was established. The samples were purified with QuEChERS approach using new adsorbents and analyzed with UPLC-MS/MS. The results showed that both of graphene and carbon nanotubes were highly efficient adsorbents for the dSPE clean up to eliminate coextractives in the samples, and graphene was superior to carbon nanotubes for the detection of pesticide residues in honey and pollen samples. The proposed method was used to detect pesticide residues in 25 honey samples and 30 pollen samples which were randomly collected from more than ten provinces in China. All honey samples contain 1-27 μg/kg of chlorpyrifos residues. Only 4% of the honey samples were detected containing acetamiprid and imidacloprid, while the other seven pesticides were not detected. Chlorpyrifos residues were found in all pollen samples (5-66 μg/kg), among which twenty percent exceeded the maximum residue limits (MRLs, 50 μg/kg, European Commission Regulation). Most of the pollen samples containing pesticide concentrations higher than MRLs were collected from rape, followed by lotus, camellia, and rose. Besides, 36.7% and 33.3% of the pollen samples had imidacloprid and flupyradifurone higher than 5 μg/kg. A total of 26.7% pollen samples were detected containing bifenthrin, while none of the other six pesticides were detected in pollen samples.

Purpose The purpose of this paper is to study the effect of micro-nano surface texture on the corrosion resistance of a titanium alloy and investigate the correlation between corrosion resistance and hydrophobicity. Design/methodology/approach The surface of the Ti6Al4V alloy was modified by laser processing and anodizing to fabricate micro-pits, nanotubes and micro-nano surface textures. Afterward, the surface morphology, hydrophobicity and polarization curve of the samples were analyzed by cold field scanning electron microscopy, contact angle measurement instruments and a multi-channel electrochemical workstation. Findings The micro-nano surface texture can enhance the hydrophobicity of the Ti6Al4V surface, which may lead to better drag reduction to ease the friction of implants in vivo. Nevertheless, no correlation existed between surface hydrophobicity and corrosion resistance; the corrosion resistance of samples with nanotubes and high-density samples with micro-nano surface texture was extremely enhanced, indicating the similar corrosion resistance of the two. Research limitations/implications The mechanism of micro-dimples on the corrosion resistance of the micro-nano surface texture was not studied. Practical implications The density of micro-pits needs to be optimized to guarantee excellent corrosion resistance in the design of the micro-nano surface texture; otherwise, it will not fulfill the requirement of surface modification. Originality/value The influence of the micro-nano surface texture on the corrosion resistance, as well as the relationship between hydrophobicity and corrosion resistance of the titanium alloy surface, were systematically investigated for the first time. These conclusions offer new knowledge.

A zirconium-based metal-organic framework (MOF) was successfully constructed via solvothermal assembly of a triphenylamine-based tricarboxylate ligand and Zr(IV) salt, the structure simulation of which revealed that it possesses a two-dimensional layered framework with a relatively rare dodecnuclear Zr12 cluster as the inorganic building unit. The inherent photo-responsive property derived from the incorporated photochromic triphenylamine groups combined with its high stability makes the constructed MOF an efficient heterogeneous photocatalyst for the oxidation of sulfides, which is a fundamentally important reaction type in both environmental and pharmaceutical industries. The photocatalytic activity of the constructed MOF was first investigated under various conditions with thioanisole as a representative sulfide substrate. The MOF exhibited both high efficiency and selectivity on aerobic oxidation of thioanisole in methanol utilizing molecular oxygen in air as the oxidant under blue light irradiation for 10 h. Its high photocatalytic performance was also observed when extending the sulfide substrate to diverse thioanisole derivatives and even a sulfur-containing nerve agent simulant (2-chloroethyl ethyl sulfide). The high photocatalytic efficiency and selectivity to a broad set of sulfide substrates make the triphenylamine-incorporating zirconium-based MOF a highly promising heterogeneous photocatalyst. Ministry of Education (MOE) This work was supported by the "Qilu Young Talent Scholar" program of Shandong University and the Singapore Academic Research Fund (RT12/19).

It is of great significance to understand the effects of different rice cultivation methods in southeast China on greenhouse gas emission characteristics and carbon footprint of paddy fields during rice cultivation for rice sustainable production. In this study, the popular conventional rice 'Jiafuzhan' and hybrid rice 'Yongyou 2640' were used as materials to establish four rice cultivation patterns suitable for different ecological types in Fujian Province: 1) double-cropping system, early rice and late rice with Jiafuzhan (D-J); 2) early maturing ratooning system, first season rice and ratooning season rice with Jiafuzhan (R-J); 3) middle-maturing ratooning system, first season rice and ratooning season with Yongyou 2640 (R-Y); and 4) single cropping system with Yongyou 2640 (S-Y), which should be synchronized in heading time with the counterpart (the ratooning season rice). Greenhouse gas emissions from paddy soil were measured by the closed static black box observation method and the gas chromatography method, respectively. The total direct and indirect greenhouse gas emissions (carbon footprints) from different rice farming patterns were evaluated by using the life cycle analysis. The results showed that greenhouse gas emissions in different rice cropping systems were lower in the early growth stage, then decreased after reaching the peak at the booting stage, demonstrating a double peak curve in the whole growth stage, in which the first peak was higher in early season or first season than the second peak in the late season or ratooning season in the cropping patterns. Moreover, the total greenhouse gas emissions were significantly different among cropping systems. The global warming potential (GWP) of different cropping patterns was in order of R-YD-JS-YR-J, while the annual greenhouse gas emission intensity (GHGI) was D-JS-YR-YR-J. GWP and GHGI of the ratooning system decreased by 26.1% and 14.1%, respectively, compared with those of the double-cropping system. The same pattern was observed in the ratooning rice of Yongyou 2640, which were decreased by 74.3% and 56.7%, respectively, compared with the counterpart, Yongyou 2640 in a single-cropping system synchronized heading. Carbon footprint of rice per unit yield ranged from 0.38-1.08 kg CO研究中国东南区域不同稻作方式对水稻生产过程中稻田温室气体排放特征及其碳足迹的影响,对促进水稻可持续生产有重要意义。本研究以当前推广的常规稻‘佳辐占'和杂交中稻‘甬优2640'为材料,构建4种适合福建不同生态类型区的稻作模式: 1) 双季稻,早稻和晚稻均种植佳辐占(D-J);2) 早熟再生稻,头季稻和再生季稻均种植佳辐占(R-J);3) 中熟再生稻,头季稻和再生季稻均种植甬优2640(R-Y);4) 单季晚稻,与中熟再生季稻同期抽穗的单季晚稻,种植甬优2640(S-Y)。采用密闭静态暗箱观测法和气相色谱法分别收集并检测稻田土壤温室气体排放量,借用生命周期法对不同稻作方式产生的直接和间接温室气体排放总量(即碳足迹)进行数据采集与比较分析。结果表明: 不同稻作方式稻田温室气体排放特征均表现为生育前期排放量较低,到孕穗期前后达到高峰后又下降,即全生育期呈前高后低的双峰曲线,其中早稻或头季稻达到的第1个峰值较相应晚稻或再生季稻的第2个峰值高。不同稻作模式稻田温室气体排放总量差异显著。各种植模式全球增温潜势(GWP)表现为:R-YD-JS-YR-J,温室气体排放强度(GHGI)表现为:D-JS-YR-YR-J;与双季稻模式相比,佳辐占再生稻模式GWP和GHGI分别降低26.1%和14.1%;与同期抽穗的单季晚稻相比,甬优2640再生季稻稻田GWP和GHGI分别降低74.3%和56.7%。不同稻作模式下水稻单位产量碳足迹为0.38~1.08 kg CO

Trifloxystrobin (TRI) and kresoxim-methyl (KRE), as quinone outside inhibitor fungicides (QoIs), have broad applications due to their effective activity against fungi. Excessive usages of agrochemicals trigger environmental risks, such as aquatic organisms (fish). Research performed in recent years has focused on the ecotoxicology of TRI and KRE in fish containing histologic morphology, enzyme activity, protein and gene expression under chronic toxicity conditions, whereas less is known about the underlying mechanisms of toxicity and differences between TRI and KRE in fish under acute toxicity conditions. In the present study, in comparison to different exposure routes [whole-body exposure (WBE), head exposure (HE), trunk exposure (TE), and Oral administration (OA)], the external substances TRI and KRE entered the fish body mainly via gill organs and led to fish toxicity. Furthermore, gill organs and gill cells were vulnerable to TRI and KRE exposure, which indicated that the gill is a vital impaired organ. The 96 h-LC

In view of the significance of food safety and the possible relationship between residual enrichment and acute toxicity for pesticides in different aquatic organisms, it is essential to establish a sensitive and reliable determination method for pesticides in different aquatic organisms to analyze the enrichment levels. Quinone outside inhibitor fungicides (QoIs) are lipophilic fungicides that pose environmental threats to aquatic organisms. Previous research has mainly focused on QoI residues in aquatic organisms under chronic toxicity, whereas less is known about how pesticide residues differ among aquatic organism under acutely toxic conditions. In the present study, the residues of QoIs in aquatic organisms (Danio rerio, Rana pipiens, Cherax quadricarinatus, Misgurnus anguillicaudatus, Corbicula fluminea, and Ampullaria gigas) were analyzed by ultrahigh-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) coupled with a proposed QuEChERS method. The proposed method was validated in terms of linearity (coefficients of determination of 0.9980-0.9999), the limits of quantification (0.01 μg·kg

In the absence of vaccines to fight the COVID-19 pandemic, in 2020 governments had to respond by rely on non-pharmaceutical interventions (NPIs). Socioeconomic inequalities likely influenced the uptake of NPIs. Using Norwegian survey data, we study whether income was associated with increased handwashing, keeping 1 m distance, using facemasks increased use of home office, and less use of public transportation. Except for using facemasks and less public transportation in a non-work context, all analyzed NPIs showed an independent positive association with income. Social disparities in NPI uptake may be important drivers of higher risks of disease outcomes for people of lower socioeconomic status.

Background Our previous works indicated that 1-octen-3-ol has promising potential as an alternative grain fumigant. However, aside from its insecticidal efficacy, the presence of 1-octen-3-ol residues in grains must be investigated to assess its food safety profile. Results A convenient and sensitive QuEChERS based GC-MS/MS method was developed to detect residues of 1-octen-3-ol in wheat. The sample pretreatment procedures were optimized. The developed method showed good linearity (R2 = 0.9999) and negligible matrix effects. The limit of detection (LOD) and limit of quantification (LOQ) for 1-octen-3-ol were 0.003 and 0.01 mg kg-1 , respectively. Recoveries at spiked concentration levels of 0.01, 0.5, 10, 100 and 200 mg kg-1 ranged from 90.8% to 112.4%, with relative standard deviations (RSDs, n = 5) ranged from 1.2 to 7.5%. In the fumigation process during wheat storage, there were positive correlations between the accumulation rate and fumigation concentration as well as between the accumulation amounts and fumigation time. In the ventilation process, temperature significantly affected the dissipation dynamics of 1-octen-3-ol in wheat, and the t1/2 values at ventilation temperatures of 30 and 5 °C for 0.1 μL mL-1 were 0.16 and 21.80 days, respectively, representing a 136-fold difference. Conclusion Preservers can regulate the ventilation temperature to achieve different goals, with either a long duration period for long-term storage or rapid dissipation for quick food consumption. This study provides guidance on the reasonable usage of 1-octen-3-ol on wheat and other stored grains. © 2021 Society of Chemical Industry.

The cooperation of magnetic and electric plasmon resonances in cup-shaped metallic nanostructures exhibits significant capability for second-harmonic generation (SHG) enhancement. Herein, we report an approach for synthesizing Au open nanoshells with tunable numbers and sizes of openings on a template of six-pointed PbS nanostars. The morphology of Au nanoshells is controlled by adjusting the amount of HAuCl4, and the characteristic shapes of pointed nanocaps, open nanoshells, and hollow nanostars are obtained. Owing to the collaboration of electric and magnetic plasmon resonance modes, the Au nanoshells exhibit significantly broadened and highly tunable optical responses. Furthermore, the morphology-dependent SHG of the Au nanoshells shows two maximal SHG intensities, corresponding to four-opening and one-opening Au nanoshells with appropriate opening sizes. Ag/Au and AuAg/Ag/Au open nanoshells were further investigated to achieve enhanced SHG. By adjusting the thickness of the Ag shell, the SHG intensity of Ag/Au open nanoshells reaches a maximum due to the gradient field at the AuAg bimetallic interface. After replacing the Ag shells with Au shells, the SHG intensity of AuAg/Ag/Au open nanoshells reaches a maximum due to further symmetry breaking. These findings provide a strategy to prepare colloidal metal nanocrystals with prospective applications ranging from nonlinear photonic nanodevices to biospectroscopy and photocatalysis.

Two novel TADF molecules, with donor#1–σ–donor#2–π–acceptor (D1–σ–D2–π–A) conformation, were designed and synthesized through-bond charge transfer (TBCT) and through-space charge transfer (TSCT). These two materials differ only in the D1 groups with triphenylamine for SFCCN and 10-phenyl-10H-phenoxazine for SFCCNO. Due to the unconjugated linkage, both materials showed very similar emission to that from D2–π–A TBCT effect in dilute solution. SFCCNO can form dimers at the aggregation state and exhibit intermolecular D1/A TSCT emission because of the planar D1 conformation. Therefore, a non-doped device based on SFCCNO exhibited efficiencies of 12.9% at 100 cd m−2 and 10.4% at 1000 cd m−2, which are much higher than the SFCCN based device.

A narrowband blue CP-TADF emitter with a rigid hetero-helicene structure (QAO-PhCz) was synthesized and characterized. QAO-PhCz exhibits good electroluminescence performance (EQE = 14.0%) and narrow FWHM. The enantiomers of QAO-PhCz display CPL and CPEL properties with |glum| and |gEL|values of up to 1.1 × 10−3 and 1.5 × 10−3, respectively.

A survey was designed to investigate the pesticide residues in agricultural produce and to estimate their potential intake risks to inhabitants. A total of 314 samples of nine types of fruits and vegetables were collected from the supermarkets and vegetable markets of Shandong Province (China) from October 2020 to February 2022. An accurate and reliable multi-residue method, based on GC-MS/MS detection, as well as the multiplug filtration cleanup method, based on SBA-15-C18, was prepared by a solution chemical reaction. Additionally, an in situ co-condensation method was established for the quantification of 139 pesticide residues. Residues that contained no pesticides were detected in 66.5% of the 314 samples. Moreover, of the samples, 30.6% were at or below the MRLs, and 2.9% were above the MRLs. Residues of procymidone were found to be the one that most often exceeded the MRLs (1.3% of the samples). Tebuconazole was found most frequently in 22.0% of the samples analyzed. Consumer exposure to the 139 pesticides did not exceed 100% ADI and ARfD. This led to a consideration that these pesticide residues in the nine commodities may not raise the health risk of the consumers in the long and short term. The highest value of chronic dietary intake was obtained from spirodiclofen, which resulted in a 24.1% of ADI. Furthermore, the highest exposure levels in the short term were obtained from the consumption of leeks with procymidone (58.3% ARfD).

The conversion of waste cooking oil (WCO) to biodiesel is promising in the green energy and sustainable development sector. In this study, ionic liquid@amphiphilic silica nanoparticles (IASNPs) com...

Supplemental Material, sj-pdf-1-ssc-10.1177_08944393211069622 for Predicting Psychological Distress During the COVID-19 Pandemic: Do Socioeconomic Factors Matter? by Nan Zou Bakkeli in Social Science Computer Review

Supplemental Material, sj-pdf-1-ssc-10.1177_08944393211069622 for Predicting Psychological Distress During the COVID-19 Pandemic: Do Socioeconomic Factors Matter? by Nan Zou Bakkeli in Social Science Computer Review

Intramolecular spatial charge transfer (ISCT) plays a critical role in determining the optical and charge transport properties of thermally activated delayed fluorescence (TADF) materials. Herein, a new donor/acceptor-type TADF compound based on rigid dibenzothiophene sulfone (DBTS) moiety

Background Gastrointestinal hemangiomas are rare benign tumors. According to the size of the affected vessels, hemangiomas are histologically classified into cavernous, capillary, or mixed-type tumors, with the cavernous type being the most common and racemose hemangiomas being very rare in the clinic. Melena of uncertain origin and anemia are the main clinical manifestations, and other presentations are rare. Due to the rarity of gastrointestinal hemangiomas and lack of specific manifestations and diagnostic methods, preoperative diagnoses are often delayed or incorrect. Case summary We report a 5-year-old girl who presented with abdominal pain, nausea, and vomiting for a duration of 10 h. The laboratory studies showed prominent anemia. Computed tomography and contrast-enhanced computed tomography of the abdomen revealed a small bowel obstruction caused by a giant abdominal mass. Segmental resection of the ileal lesions was performed through surgery, and the final pathology results revealed a diagnosis of racemose hemangioma complicated by a small bowel obstruction and simultaneous chronic anemia. Conclusion The current report will increase the understanding of the diagnosis and treatment of gastrointestinal hemangiomas and provide a review of the related literature.

Organic heterostructures (OHSs) consist of organic micro/nanocrystals are of essential importance for the construction of integrated optoelectronics in the future. However, the scarcity of materials and the problem of phase separation still hinder the fine synthesis of OHSs. Herein, based on the α phase one-dimensional (1D) microrods and the β phase 2D microplates of one organic compound 3,3′-((1 E ,1′ E )-anthracene-9,10-diylbis(ethane-2,1-diyl))dibenzonitril ( m -B2BCB), we facilely synthesized the OHSs composed of these two polymorph phases, whose growth mechanism is attributed to the low lattice mismatch rate of 5.8% between (001) plane of α phase (trunk) and (010) crystal plane of β phase (branch). Significantly, the multiport in/output channels can be achieved in the OHSs, which demonstrates the structure-dependent optical signals with the different output channels in the OHSs. Therefore, our experiment exhibits the great prospect of polymorphism in OHSs, which could provide further applications on multifunctional organic integrated photonics circuits.

Laser radar (Lidar) plays an indispensable role in lots of security critical applications such as autonomous driving. However, the high sparsity and non-uniformity nature of the raw laser data brings large difficulties to reliable 3D scene understanding. Traditional depth completion methods suffer from the highly ill-conditioned nature of the problem. A novel end-to-end road semantic guided depth completion neural network with a special designed Asymmetric Multiscale Convolution (AMC) structure is proposed in this paper. The whole network is composed of two parts: semantic part and depth completion part. The semantic part is constructed by an image-Lidar joint segmentation sub-network which produces semantic masks (ground or object) to the following network. The depth completion part is composed of a series of AMC convolution structure. By combining the semantic masks and treating the ground and non-ground objects separately, the proposed AMC structure can well fit the depth distribution pattern implied in road scene. The experiments carried on both synthesized and real datasets demonstrate that our method can effectively improve the accuracy of depth completion results.

Drought stress reduces soybean yield. Exploring the mechanism of improving drought tolerance and reducing yield loss is of great significance for soybean production. Melatonin application can alleviate the growth inhibition and oxidative damage of plants under drought stress. In this experiment, the effects of foliar application of melatonin on photosynthesis, stress resistance, carbon and nitrogen metabolism and yield of soybean during seed filling stage under drought stress were studied in 2017–2018. The application exogenous melatonin increased the antioxidant enzyme activity, inhibited the production of reactive oxygen species, decreased cell membrane damage under drought stress, alleviated the inhibition of photosynthetic capacity by drought stress, improved the carbon and nitrogen assimilation ability, and alleviated the yield loss caused by drought stress. Compared with drought stress, the treatment of melatonin increased the number of pods per plant, the grain number per plant and the hundred grain weight by 2.9%, 0.8%, and 17.2% on average of two years, respectively, and the yield (grain weight per plant) increased by 14.7%.

Two intermetallic compounds τ 1 (i.e. Zr(Fe, Cu)) and τ 2 (i.e. Zr 2 (Fe, Cu)) with unconfirmed structures in the Zr–Fe–Cu ternary system have been identified and the equilibrium phase relationship of the quaternary Zr–Nb–Fe–Cu system at 700 °C and 580 °C have been experimentally investigated by using optical microscopy, electron probe micro-analyzer coupled with wavelength-dispersive spectroscopy, transmission electron microscopy and X-ray diffraction on the equilibrated alloys. In the ternary Zr–Fe–Cu system, the results show that τ 1 has the same structure as ZrCu phase with cubic CsCl-type structure, and the structure of τ 2 phase is the same as Zr 2 Fe with tetragonal Al 2 Cu-type structure. The solution mechanism of alloying elements for the τ 1 compound is that the Cu sites are occupied by Fe atoms to stabilize the ZrCu structure, in the meanwhile, the mechanism of τ 2 is that the Fe sites are occupied by Cu atoms. For the quaternary Zr–Nb–Fe–Cu system, there is no new quaternary intermetallic phase detected in the present work. Only three intermetallic compounds, i.e. λ 1 , λ 2 and τ 2 , presented in sub-ternaries were identified in the quaternary system at both 700 °C and 580 °C. It was found that Cu atoms dissolve in λ 1 and λ 2 phases forming cubic (Zr, Nb) 2 (Fe, Cu) and hexagonal (Cu, Fe, Nb) 2 Zr respectively, and Nb atoms dissolve in τ 2 phase forming tetragonal (Zr, Nb) 2 (Fe, Cu).

There is growing evidence that mammalian cells deploy a mitochondria-associated metabolon called the purinosome to perform channeled de novo purine biosynthesis (DNPB). However, the molecular mechanisms of this substrate-channeling pathway are not well defined. Here, we present molecular evidence of protein-protein interactions (PPIs) between the human bifunctional phosphoribosylaminoimidazole carboxylase/succinocarboxamide synthetase (PAICS) and other known DNPB enzymes. We employed two orthogonal approaches: bimolecular fluorescence complementation, to probe PPIs inside live, intact cells, and co-immunoprecipitation using StrepTag-labeled PAICS that was reintegrated into the genome of PAICS-knockout HeLa cells (crPAICS). With the exception of amidophosphoribosyltransferase, the first enzyme of the DNPB pathway, we discovered PAICS interacts with all other known DNPB enzymes and with MTHFD1, an enzyme which supplies the 10-formyltetrahydrofolate cofactor essential for DNPB. We show these interactions are present in cells grown in both purine-depleted and purine-rich conditions, suggesting at least a partial assembly of these enzymes may be present regardless of the activity of the DNPB pathway. We also demonstrate that tagging of PAICS on its C terminus disrupts these interactions and that this disruption is correlated with disturbed DNPB activity. Finally, we show that crPAICS cells with reintegrated N-terminally tagged PAICS regained effective DNPB with metabolic signatures of channeled synthesis, whereas crPAICS cells that reintegrated C-terminally tagged PAICS exhibit reduced DNPB intermediate pools and a perturbed partitioning of inosine monophosphate into AMP and GMP. Our results provide molecular evidence in support of purinosomes and suggest perturbing PPIs between DNPB enzymes negatively impact metabolite flux through this important pathway.