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Whether a solar eruption is successful or failed depends on the competition between different components of the Lorentz force exerting on the flux rope that drives the eruption. The present models only consider the strapping force generated by the background magnetic field perpendicular to the flux rope and the tension force generated by the field along the flux rope. Using the observed magnetic field on the photosphere as a time-matching bottom boundary, we perform a data-driven magnetohydrodynamic simulation for the 30 January 2015 confined eruption and successfully reproduce the observed solar flare without a coronal mass ejection. Here we show a Lorentz force component, resulting from the radial magnetic field or the non-axisymmetry of the flux rope, which can essentially constrain the eruption. Our finding contributes to the solar eruption model and presents the necessity of considering the topological structure of a flux rope when studying its eruption behaviour. The competition between different components of the Lorentz force defines whether a solar eruption fails or not. Here, the authors show a new Lorentz force component, which plays a major role in preventing magnetic flux ropes from erupting successfully.

Magnetic reconnection is a key mechanism involved in solar eruptions and is also a prime possibility to heat the low corona to millions of degrees. Here, we present ultra-high-resolution extreme ultraviolet observations of persistent null-point reconnection in the corona at a scale of about 390 km over one hour observations of the Extreme-Ultraviolet Imager on board Solar Orbiter spacecraft. The observations show formation of a null-point configuration above a minor positive polarity embedded within a region of dominant negative polarity near a sunspot. The gentle phase of the persistent null-point reconnection is evidenced by sustained point-like high-temperature plasma (about 10 MK) near the null-point and constant outflow blobs not only along the outer spine but also along the fan surface. The blobs appear at a higher frequency than previously observed with an average velocity of about 80 km s −1 and life-times of about 40 s. The null-point reconnection also occurs explosively but only for 4 minutes, its coupling with a mini-filament eruption generates a spiral jet. These results suggest that magnetic reconnection, at previously unresolved scales, proceeds continually in a gentle and/or explosive way to persistently transfer mass and energy to the overlying corona. Magnetic reconnection is a fundamental energy release mechanism in space and laboratory plasmas. Here, the authors show persistent magnetic null-point reconnection in the solar corona at a scale of about 390 km.

Using gas chromatography mass spectrometry and the PacBio single molecule with real-time sequencing technology (SMRT), we analyzed the detailed metabolomic profiles and microbial community dynamics involved in ensiled Medicago sativa (alfalfa) inoculated without or with the homofermenter Lactobacillus plantarum or heterofermenter Lactobacillus buchneri . Our results revealed that 280 substances and 102 different metabolites were present in ensiled alfalfa. Inoculation of L. buchneri led to remarkable up-accumulation in concentrations of 4-aminobutyric acid, some free amino acids, and polyols in ensiled alfalfa, whereas considerable down-accumulation in cadaverine and succinic acid were observed in L. plantarum -inoculated silages. Completely different microbial flora and their successions during ensiling were observed in the control and two types of inoculant-treated silages. Inoculation of the L. plantarum or L. buchneri alters the microbial composition dynamics of the ensiled forage in very different manners. Our study demonstrates that metabolomic profiling analysis provides a deep insight in metabolites in silage. Moreover, the PacBio SMRT method revealed the microbial composition and its succession during the ensiling process at the species level. This provides information regarding the microbial processes underlying silage formation and may contribute to target-based regulation methods to achieve high-quality silage production.

A unified set of predictions for pion and kaon elastic electromagnetic and gravitational form factors is obtained using a symmetry-preserving truncation of each relevant quantum field equation. A key part of the study is a description of salient aspects of the dressed graviton + quark vertices. The calculations reveal that each meson’s mass radius is smaller than its charge radius, matching available empirical inferences; and meson core pressures are commensurate with those in neutron stars. The analysis described herein paves the way for a direct calculation of nucleon gravitational form factors.

Beginning with results for the leading-twist two-particle distribution amplitudes of π - and K -mesons, each of which exhibits dilation driven by the mechanism responsible for the emergence of hadronic mass, we develop parameter-free predictions for the pointwise behaviour of all π and K distribution functions (DFs), including glue and sea. The large- x behaviour of each DF meets expectations based on quantum chromodynamics; the valence-quark distributions match extractions from available data, including the pion case when threshold resummation effects are included; and at ζ 5 = 5.2 GeV, the scale of existing measurements, the light-front momentum of these hadrons is shared as follows: ⟨ x valence ⟩ π = 0.41 ( 4 ) , ⟨ x glue ⟩ π = 0.45 ( 2 ) , ⟨ x sea ⟩ π = 0.14 ( 2 ) ; and ⟨ x valence ⟩ K = 0.42 ( 3 ) , ⟨ x glue ⟩ K = 0.44 ( 2 ) , ⟨ x sea ⟩ K = 0.14 ( 2 ) . The kaon’s glue and sea distributions are similar to those in the pion, although the inclusion of mass-dependent splitting functions introduces some differences on the valence-quark domain. This study should stimulate improved analyses of existing data and motivate new experiments sensitive to all π and K DFs. With little known empirically about the structure of the Standard Model’s (pseudo-) Nambu-Goldstone modes and analyses of existing, limited data being controversial, it is likely that new generation experiments at upgraded and anticipated facilities will provide the information needed to resolve the puzzles and complete the picture of these complex bound states.

In the process of rapid urbanization, any unexpected event will harm the stability of the city. Strengthening urban resilience construction will effectively respond to unexpected events. Taking 22 counties (cities, districts) in Ningxia, Northwest China as the research object, 20 indicators are selected from four aspects of economic, social, infrastructure, and ecological resilience to construct an urban resilience evaluation index system. The entropy-TOPSIS model (consisting of the Entropy method and the Technique for Order Preference by Similarity to an Ideal Solution method) is used to comprehensively evaluate the resilience and comprehensive resilience of various dimensions of county-level cities. The results show that: (1) There is a significant spatial differentiation in the economic, social, infrastructure, and ecological resilience of county-level cities in Ningxia, resulting in a higher comprehensive resilience of cities in the northern region compared to those in the southern region, and comparatively high and high resilience is distributed in the central districts and counties of the northern and southern regions. (2) Low, comparatively low, medium, comparatively high, and high resilience cities account for 13.64%, 31.82%, 31.82%, 18.18% and 4.54% of the total number of county-level cities in Ningxia, respectively. Among them, Xingqing District has the highest comprehensive resilience and Jingyuan County has the lowest comprehensive resilience. The research findings can provide a basis for the dynamic assessment of resilience in county-level cities in Ningxia, the analysis of the impact of geological environment changes on urban resilience, and thus a theoretical and practical basis for the sustainable development of county-level cities in Ningxia and the enhancement of their ability to respond to emergencies.

Inhibitors against poly (ADP-ribose) polymerase (PARP) are promising targeted agents currently used to treat BRCA -mutant ovarian cancer and are in clinical trials for other cancer types, including BRCA -mutant breast cancer. To enhance the clinical response to PARP inhibitors (PARPis), understanding the mechanisms underlying PARPi sensitivity is urgently needed. Here, we show enhancer of zeste homolog 2 (EZH2), an enzyme that catalyzes H3 lysine trimethylation and associates with oncogenic function, contributes to PARPi sensitivity in breast cancer cells. Mechanistically, upon oxidative stress or alkylating DNA damage, PARP1 interacts with and attaches poly-ADP-ribose (PAR) chains to EZH2. PARylation of EZH2 by PARP1 then induces PRC2 complex dissociation and EZH2 downregulation, which in turn reduces EZH2-mediated H3 trimethylation. In contrast, inhibition of PARP by PARPi attenuates alkylating DNA damage-induced EZH2 downregulation, thereby promoting EZH2-mediated gene silencing and cancer stem cell property compared with PARPi-untreated cells. Moreover, the addition of an EZH2 inhibitor sensitizes the BRCA -mutant breast cells to PARPi. Thus, these results may provide a rationale for combining PARP and EZH2 inhibition as a therapeutic strategy for BRCA- mutated breast and ovarian cancers.

Motivated by experimental initiatives such as the Helmholtz International Beamline for Extreme Fields, we study Compton scattering of x-rays at electrons in a strong external field (e.g. a strong optical laser) with special emphasis on the polarization-changing contribution on the amplitude level. Apart from advancing our theoretical understanding, the goal of this study is two-fold. On the one hand, Compton scattering is a potential background process for the planned vacuum birefringence experiments. On the other hand, this effect could be used for diagnostic purposes. Since the polarization-changing signal from free electrons (i.e. without the external field) vanishes in forward direction, the ratio of the polarization-changing and the normal (polarization conserving) contribution yields information about the field strength at the interaction point.

Background/Objectives: Evidence regarding the consumption of soy foods and isoflavones in relation to risk of type 2 diabetes (T2D) is scarce. Our study was to evaluate the association between soy food and isoflavone consumption and risk of T2D in US men and women. Subjects/Methods: We followed 63 115 women in the Nurses’ Health Study (1998–2012), 79 061 women in the Nurses’ Health Study II (1999–2013) and 21 281 men in the Health Professionals Follow-Up Study (2002–2010). Diet was assessed by a validated food-frequency questionnaire and was updated every 4 years. Self-reports of incident T2D were confirmed by a validated supplementary questionnaire. Results: During 1 966 321 person-years of follow-up, 9185 incident T2D cases were documented. After multivariate adjustment for covariates, consumption of soy foods (tofu and soy milk) was not associated with a lower T2D risk. Compared with non-consumers of soy foods, the hazard ratio (HR) was 1.00 (95% confidence interval (CI): 0.93, 1.07) for <1 serving/week and 0.93 (95% CI: 0.83, 1.03) for ⩾1 serving/week of soy foods ( P for trend=0.14). In contrast, intake of total isoflavones was inversely associated with T2D risk. Comparing extreme quintiles of isoflavones, the HR was 0.89 (95% CI: 0.83, 0.96; P for trend=0.009). Inverse associations were also found for consumption of major individual isoflavones, including daidzein and genistein, with risk of T2D. Conclusions: Intake of isoflavones was associated with a modestly lower T2D risk in US men and women who typically consumed low-to-moderate amounts of soy foods. These findings warrant replications in other populations with similar soy intake levels.

White-light flares are the flares with emissions visible in the optical continuum. They are thought to be rare and pose the most stringent requirements in energy transport and heating in the lower atmosphere. Here we present a nearly circular white-light flare on 10 March 2015 that was well observed by the Optical and Near-infrared Solar Eruption Tracer and Solar Dynamics Observatory. In this flare, there appear simultaneously both impulsive and gradual white-light kernels. The generally accepted thick-target model would be responsible for the impulsive kernels but not sufficient to interpret the gradual kernels. Some other mechanisms including soft X-ray backwarming or downward-propagating Alfvén waves, acting jointly with electron beam bombardment, provide a possible interpretation. However, the origin of this kind of white-light kernel is still an open question that induces more observations and researches in the future to decipher it. White-light flares are rare solar events entailing emission in the optical continuum. Here, the authors report a nearly circular white-light flare observed on March 10th 2015 that contains simultaneously both impulsive and gradual white-light kernels.