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Hypericum perforatum, also known as "natural fluoxetine," is a commonly used herbal remedy for treating depression. It is unclear whether melatonin in plants regulated by the endogenous circadian clock system is like in vertebrates. In this work, we found that the melatonin signal and melatonin biosynthesis gene, serotonin N-acetyltransferase HpSNAT1, oscillates in a 24-hour cycle in H. perforatum. First, we constructed a yeast complementary DNA library of H. perforatum and found a clock protein HpLHY that can directly bind to the HpSNAT1 promoter. Second, it was confirmed that HpLHY inhibits the expression of HpSNAT1 by targeting the Evening Element. Last, it indicated that HpLHY-overexpressing plants had reduced levels of melatonin in 12-hour light/12-hour dark cycle photoperiod, while loss-of-function mutants exhibited high levels, but this rhythm seems to disappear as well. The results revealed the regulatory role of LHY in melatonin biosynthesis, which may make an important contribution to the field of melatonin synthesis regulation. [ABSTRACT FROM AUTHOR]

With global warming, the global ocean is experiencing more and stronger marine heatwaves (MHWs) and less and weaker marine cold spells (MCSs). On the regional scale, the complex circulation structure means that the changes in sea surface temperature (SST) and extreme temperature anomaly events in the Taiwan Strait (TWS) exhibit unique regional characteristics. In summer (autumn), the SST in most regions of the TWS has a significant increasing trend with a regionally averaged rate of 0.22 °C (0.19 °C) per decade during the period 1982–2021. In winter and spring, the SST in the western strait shows a significant decreasing trend with a maximum decreasing rate of −0.48 °C per decade, while it shows an increasing trend in the eastern strait. The annual mean results show that the TWS is experiencing more MHWs and MCSs with time. The frequency of the MHWs in the eastern strait is increasing faster than that in the western strait. In the western region controlled by the Zhe-Min Coastal Current, the MCSs have an increasing trend while in the other areas they have a decreasing trend. The MHWs occur in most areas of the TWS in summer and autumn, but the MCSs are mainly concentrated in the west of the TWS in spring and winter. The cooling effect of summer upwelling tends to inhibit the occurrence of MHWs and enhance MCSs. The rising background SST is a dominant driver for the increasing trend of summer MHWs. By contrast, both the SST decreasing trend and internal variability contribute to the winter MCSs increasing trend in the strait. [ABSTRACT FROM AUTHOR]

The evolutionary conservation of non-core RAG regions suggests significant roles that might involve quantitative or qualitative alterations in RAG activity. Off-target V(D)J recombination contributes to lymphomagenesis and is exacerbated by RAG2' C-terminus absence in Tp53-/- mice thymic lymphomas. However, the genomic stability effects of non-core regions from both Rag1c/c and Rag2c/c in BCR-ABL1+ B-lymphoblastic leukemia (BCR-ABL1+ B-ALL), the characteristics, and mechanisms of non-core regions in suppressing off-target V(D)J recombination remain unclear. Here, we established three mouse models of BCR-ABL1+ B-ALL in mice expressing full-length RAG (Ragf/f), core RAG1 (Rag1c/c), and core RAG2 (Rag2c/c). The Ragc/c (Rag1c/c and Rag2c/c) leukemia cells exhibited greater malignant tumor characteristics compared to Ragf/f cells. Additionally, Ragc/c cells showed higher frequency of off-target V(D)J recombination and oncogenic mutations than Ragf/f. We also revealed decreased RAG cleavage accuracy in Ragc/c cells and a smaller recombinant size in Rag1c/c cells, which could potentially exacerbate off-target V(D)J recombination in Ragc/c cells. In conclusion, these findings indicate that the non-core RAG regions, particularly the non-core region of RAG1, play a significant role in preserving V(D)J recombination precision and genomic stability in BCR-ABL1+ B-ALL. [ABSTRACT FROM AUTHOR]

In July to August 2022, Pakistan suffered historic flooding while record-breaking heatwaves swept southern China, causing severe socioeconomic impacts. Similar extreme events have frequently coincided between two regions during the past 44 years, but the underlying mechanisms remain unclear. Using observations and a suite of model experiments, here, we show that the upper-tropospheric divergent wind induced by convective heating over Pakistan excites a barotropic anomalous anticyclone over eastern China, which further leads to persistent heatwaves. Atmospheric model ensemble simulation indicates that this dynamic pathway linking Pakistan flooding and East Asian heatwaves is intrinsic to the climate system, largely independent of global sea surface temperature forcing. This dynamic connection is most active during July to August when convective variability is large over Pakistan and the associated divergent flow excites barotropic Rossby waves that propagate eastward along the upper troposphere westerly waveguide. This robust waveguide and the time delay offer hopes for improved subseasonal prediction of extreme events in East Asia. [ABSTRACT FROM AUTHOR]

Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) is an invasive alien species that causes major losses in the Chinese tomato industry. Historically, insecticides have been used extensively to control T. absoluta, but resistant populations have been frequently detected. Biological control represents a sustainable and effective method with which to prevent and control T. absoluta. Egg parasitoids from the family of Trichogrammatidae (Hymenoptera) have been identified as potential biological option for controlling of T. absoluta. In the present study, we aimed to identify local dominant Trichogramma species that exhibited the best biological control ability against T. absoluta in China. To accomplish this, we compared the selectivity and number of offspring of three Trichogramma species to T. absoluta by performing host preference experiments in the laboratory. We also evaluated the fitness of Trichogramma against T. absoluta by assessing the parasitic ability and behavior of their offspring on different hosts. Compared with Trichogramma chilonis and Trichogramma dendrolimi, Trichogramma ostriniae exhibited a significantly greater preference to T. absoluta eggs and produced a higher number of offspring. The emergence rate and proportion of female T. ostriniae parasitizing the eggs of T. absoluta was higher than that of the other two Trichogramma species, the rate of T. ostriniae offspring deformity was only 3.00%. In addition, T. ostriniae has shortest immature stage and the longest adult stage among the three species. In conclusion T. ostriniae can be a promising native biological control agent against T. absoluta in China. [ABSTRACT FROM AUTHOR]

Lower-limb exoskeletons (LLEs) can provide rehabilitation training and walking assistance for individuals with lower-limb dysfunction or those in need of functionality enhancement. Adapting and personalizing the LLEs is crucial for them to form an intelligent human–machine system (HMS). However, numerous LLEs lack thorough consideration of individual differences in motion planning, leading to subpar human performance. Prioritizing human physiological response is a critical objective of trajectory optimization for the HMS. This paper proposes a human-in-the-loop (HITL) motion planning method that utilizes surface electromyography signals as biofeedback for the HITL optimization. The proposed method combines offline trajectory optimization with HITL trajectory selection. Based on the derived hybrid dynamical model of the HMS, the offline trajectory is optimized using a direct collocation method, while HITL trajectory selection is based on Thompson sampling. The direct collocation method optimizes various gait trajectories and constructs a gait library according to the energy optimality law, taking into consideration dynamics and walking constraints. Subsequently, an optimal gait trajectory is selected for the wearer using Thompson sampling. The selected gait trajectory is then implemented on the LLE under a hybrid zero dynamics control strategy. Through the HITL optimization and control experiments, the effectiveness and superiority of the proposed method are verified. [ABSTRACT FROM AUTHOR]

Mineral oil saturated hydrocarbons (MOSHs) are commonly found in food packaging printing inks. They can migrate into packaged food, posing risks to human health. In this study, a bio-based coating using sugarcane fibre (SF), anionic starch (AS), nanofibrated cellulose (NFC), and chitosan (CTS) is developed and applied to the internal surface of a food packaging white cardboard. The coating is investigated for its efficiency in reducing MOSH migration into dry food simulants (Porapak). The MOSH adsorption capacity of coated white cardboard is 4.6 and 14 times greater than those of uncoated and polythene (PE)-coated versions, respectively. Hence, the surface of SF-AS-NFC-CTS coating functions as a sponge and protective screen, adsorbing and hindering significant amounts of MOSH and subsequently slowing and reducing the migration of MOSH to food. Meanwhile, the basic properties, such as mechanical properties, air permeability (barrier property to MOSH), oil resistance, thermal stability, and antibacterial efficacy, of the coated cardboard for food packaging are all improved. Therefore, this study can offer a promising solution to food contamination concerns for food packaging. • SF-AS-NFC-CTS coating improves the gas barrier properties of white cardboard. • SF-AS-NFC-CTS coating enhances the antibacterial performance of the cardboard. • SF-AS-NFC-CTS exhibits excellent adsorption and slow discharge effect on MOSH. • SF-AS-NFC-CTS coating improved gas–oil barrier characteristics. [ABSTRACT FROM AUTHOR]

To effectively control the infection of plant pathogens, we designed and synthesized a series of phenylthiazole derivatives containing a 1,3,4-thiadiazole thione moiety and screened for their antibacterial potencies against Ralstonia solanacearum, Xanthomonas oryzae pv. oryzae, as well as their antifungal potencies against Sclerotinia sclerotiorum, Rhizoctonia solani, Magnaporthe oryzae and Colletotrichum gloeosporioides. The chemical structures of the target compounds were characterized by 1H NMR, 13C NMR and HRMS. The bioassay results revealed that all the tested compounds exhibited moderate-to-excellent antibacterial and antifungal activities against six plant pathogens. Especially, compound 5k possessed the most remarkable antibacterial activity against R. solanacearum (EC50 = 2.23 μg/mL), which was significantly superior to that of compound E1 (EC50 = 69.87 μg/mL) and the commercial agent Thiodiazole copper (EC50 = 52.01 μg/mL). Meanwhile, compound 5b displayed the most excellent antifungal activity against S. sclerotiorum (EC50 = 0.51 μg/mL), which was equivalent to that of the commercial fungicide Carbendazim (EC50 = 0.57 μg/mL). The preliminary structure-activity relationship (SAR) results suggested that introducing an electron-withdrawing group at the meta-position and ortho-position of the benzene ring could endow the final structure with remarkable antibacterial and antifungal activity, respectively. The current results indicated that these compounds were capable of serving as promising lead compounds. [ABSTRACT FROM AUTHOR]

• This study provides new insights into the P–T – t history of deeply-subducted continental crust with the utilization of zircon petrochronology. • Identification of omphacite, phengite and garnet inclusions in zircons indicate that the felsic crust probably has transformed during the eclogite-facies metamorphism. • P–T – t path of the orthogneisses demonstrates two-stages of exhumation for the UHP terrane. The early-stage faster exhumation is likely related to melt activity. Reconstruction of pressure–temperature–time (P – T – t) path of volumetrically-dominant orthogneisses in deeply subducted continental crusts is challenging due to their simple amphibolite-facies mineral assemblages. To provide new insights into this issue, a detailed study of mineral inclusions, trace elements and U-Pb ages within robust zircon containers, together with titanite U-Pb dating and petrology were conducted on ultrahigh-pressure (UHP) orthogneisses from the northern Sulu belt. The following P–T–t conditions of three metamorphic stages were constrained: (i) cathodoluminescence (CL)-grey zircon cores (ca. 238–237 Ma) with flat heavy rare earth element (HREE) patterns include garnet, phengite and omphacite that yield estimated P–T conditions of 2.3–2.8 GPa/730–800 °C, corresponding to prograde high-pressure (HP) metamorphism before the UHP peak. (ii) CL-dark zircon mantles (ca. 224 Ma) contain multiphase solid inclusions of plagioclase + K-feldspar + quartz and show extremely low Th/U ratios (≤0.08) and negative Eu anomalies, demonstrating their crystallization from hydrous melt at 2.0–1.8 GPa/890–820 °C during HP eclogite-facies exhumation. In addition, titanite grains are characterized by high LREE contents (1939–5239 ppm), Th/U ratios (0.37–0.81) and crystallization temperatures (830–801 °C), suggesting their peritectic origin. The lower intercept age (220 ± 4 Ma) of titanite is broadly consistent with the ages of the zircon mantles, indicating that they both crystallized from the melt at the same stage. (iii) CL-bright zircon rims (ca. 212–211 Ma) preserve low-pressure mineral inclusions of plagioclase, K-feldspar and quartz, and they show low Th/U ratios (0.03–0.12) and steep HREE patterns with negative Eu anomalies, witnessing amphibolite-facies overprinting at 1.0–0.8 GPa/610–550 °C. Combined with the metamorphic peak conditions of 3.2 GPa/840 °C at ca. 232 Ma constrained by previous studies from the same area, the P – T – t path of the northern Sulu UHP belt is reconstructed. The data reflects two-stage exhumation of this terrane, including an early-stage (5.8 km/m.y.) and a later-stage slower (3.1 km/m.y.) exhumation processes. The faster exhumation during early decompression was probably enhanced by extensive melting activity recorded by the CL-dark zircon mantles from the orthogneisses. [ABSTRACT FROM AUTHOR]