Superconductivity arises from two distinct quantum phenomena: electron pairing and long-range phase coherence. In conventional superconductors, the two quantum phenomena generally take place ...simultaneously, while in the underdoped high- Tc cuprate superconductors, the electron pairing occurs at higher temperature than the long-range phase coherence. Recently, whether electron pairing is also prior to long-range phase coherence in single-layer FeSe film on SrTiO3 substrate is under debate. Here, by measuring Knight shift and nuclear spin-lattice relaxation rate, we unambiguously reveal a pseudogap behavior below Tp∼60 K in two kinds of layered FeSe-based superconductors with quasi2D nature. In the pseudogap regime, a weak diamagnetic signal and a remarkable Nernst effect are also observed, which indicates that the observed pseudogap behavior is related to superconducting fluctuations. These works confirm that strong phase fluctuation is an important character in the 2D iron-based superconductors as widely observed in high-Tc cuprate superconductors.
The importance of the spin-orbit coupling (SOC) effect in Fe-based superconductors (FeSCs) has recently been under hot debate. Considering the Hund’s coupling-induced electronic correlation, the ...understanding of the role of SOC in FeSCs is not trivial and is still elusive. Here, through a comprehensive study ofSe77andFe57nuclear magnetic resonance, a nontrivial SOC effect is revealed in the nematic state of FeSe. First, the orbital-dependent spin susceptibility, determined by the anisotropy of theFe57Knight shift, indicates a predominant role from the3dxyorbital, which suggests the coexistence of local and itinerant spin degrees of freedom in the FeSe. Then, we reconfirm that the orbital reconstruction below the nematic transition temperature (Tnem∼90K) happens not only on the3dxzand3dyzorbitals but also on the3dxyorbital, which is beyond a trivial ferro-orbital order picture. Moreover, our results also indicate the development of a coherent coupling between the local and itinerant spin degrees of freedom belowTnem, which is ascribed to a Hund’s coupling-induced electronic crossover on the3dxyorbital. Finally, because of a nontrivial SOC effect, sizable in-plane anisotropy of the spin susceptibility emerges in the nematic state, suggesting a spin-orbital-intertwined nematicity rather than a simple spin- or orbital-driven nematicity. The present work not only reveals a nontrivial SOC effect in the nematic state but also sheds light on the mechanism of nematic transition in FeSe.
A thermal model considering the heat generated by friction and plastic deformation is developed for friction stir welding. The proportion of heat-generated between friction and plastic deformation ...depends on the contact states determined by the temperature and velocity of the tool. The model is verified by welding experiment, and the numerical results agree with the experimental data. Then, the effects of process parameters on temperature and residual stress are investigated using the validated model. These process parameters involve the welding speed, rotational speed, and axial force. The results show that the temperature increases with the increase of the rotational speed and axial force, and decreases with the increase of the welding speed. The increase of the axial force and welding speed will lead to larger tensile stress in the weld zone. Furthermore, the relationship between peak temperature, peak residual stress, and process parameters are established though regression method.
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.
Radical species and electric fields produced by gas plasmas are increasingly used in dermatology. Plasma-poration is the key basis for the efficient plasma skin treatment, which involves the plasma ...electric field, the directional motion of charged particles, and the transport of reactive particles. However, the enabling mechanisms of the plasma-poration remain unclear and require urgent attention. Here, the plasma-induced electric fields in each skin layer are accurately measured for the first time. The maximum electric field in the stratum corneum is 43 kV/cm, while the electric field in the active epidermis and dermis is about 1.8 kV/cm. This electric field strength is in the range of strength required for electroporation. Different from traditional electroporation treatments, the plasma-poration mainly relies on the effects of strong electric fields and the conductive current. The active power of the plasma-poration up to 18.5 kW/cm3 in the stratum corneum can rapidly change the structure of the skin. At the same time, reactive oxygen and nitrogen species also pass through the stratum corneum and effectively interact with the skin tissue. The plasma-poration does not cause any pain, which is an inevitable side effect of common electroporation.
Mechanism of the plasma-poration and its comparison with traditional electroporation. (a) Mechanism of plasma-poration. In this work, when the plasma is applied topically on the skin, an electric field of up to 43 kV/cm is generated in the stratum corneum (SC), which is sufficient to induce pores in the cell membrane. At the same time, the active power density of the conduction current generated by the charged particles flow is up to 18.5 kW/cm3, which produces a thermal effect to heat the SC and rapidly changes the SC structure leading to better skin permeability. (b) A large number of RONS generated in plasmas penetrate transcutaneously and contact with human tissues, which is the key to the biomedical effects of plasmas. Conventional electroporation does not produce such effects. Conventional electroporation current is more than 1.5 A. Compared with traditional electroporation, the current of the plasma-poration is only 0.014 A. This allows the plasma treatment to avoid any electric shock, which is an inevitable side effect of conventional electroporation. Display omitted
•Plasma-poration changes the structure of the stratum corneum and enables the effective transport of reactive species.•The maximum plasma-generated electric field in the stratum corneum is 43 kV/cm.•The active power of the plasma-poration in the stratum corneum is 18.5 kW/cm3.
Objective
This study aimed to evaluate the clinical value of urinary biomarkers including kidney injury molecule-1 (KIM-1), neutrophil gelatinase-associated lipocalin (NGAL), and monocyte ...chemoattractant protein-1 (MCP-1) in lupus nephritis.
Methods
A total of 109 biopsy-proven lupus nephritis patients were included and 50 healthy individuals were used as normal controls. Urinary KIM-1, NGAL, and MCP-1 levels were measured by ELISA and their correlations with clinical and histological features were assessed. Receiver operating characteristic curves were performed and the Cox regression model was applied to identify prognostic factors associated with renal outcomes.
Results
Active lupus nephritis patients exhibited elevated urinary levels of KIM-1, NGAL, and MCP-1 compared with lupus nephritis patients in remission (P < 0.001) and normal controls (P < 0.001). The urinary KIM-1 level was correlated with pathological tubular atrophy (r = 0.208, P < 0.05) and increased significantly in the presence of interstitial inflammatory lesions (P = 0.031). Urinary KIM-1, NGAL, and MCP-1 levels were higher in patients with active tubulointerstitial lesions than in those with only chronic lesions (P = 0.015, P = 0.230, and P = 0.086, respectively). A combination of KIM-1, NGAL, and MCP-1 was a good indicator for diagnosing active tubulointerstitial lesions (area under the curve: 0.796). The combination of KIM-1 and NGAL was identified as an independent risk factor for renal outcomes (hazard ratio = 7.491, P < 0.05).
Conclusion
Urinary KIM-1, NGAL, and MCP-1 levels were associated with kidney injury indices in lupus nephritis. The combination of the three biomarkers showed increased power in predicting tubulointerstitial lesions and renal outcomes.
Bioavailability is an eternal topic that cannot be circumvented by peroral drug delivery. Adequate blood drug exposure after oral administration is a prerequisite for effective treatment. ...Nanovesicles as pleiotropic oral vehicles can solubilize, encapsulate, stabilize an active ingredient and promote the payload absorption via various mechanisms. Vesicular systems with nanoscale size, such as liposomes, niosomes and polymersomes, provide a versatile platform for oral delivery of drugs with distinct nature. The amphiphilicity of vesicles in structure allows hydrophilic and lipophilic molecule(s) either or both to be loaded, being encapsulated in the aqueous cavity or the inner core, respectively. Depending on high oral transport efficiency based on their structural flexibility, gastrointestinal stability, biocompatibility, and/or intestinal epithelial affinity, nanovesicles can markedly augment the oral bioavailability of various poorly absorbed drugs. Vesicular drug delivery systems (VDDSs) demonstrate a lot of preferences and are becoming more prominent of late years in biomedical applications. Equally, these systems can potentiate a drug's therapeutic index by ameliorating the oral absorption. This review devotes to comment on various VDDSs with special emphasis on the peroral drug delivery. The classification of nanovesicles, preparative processes, intestinal transport mechanisms, in vivo fate, and design rationale were expounded. Knowledge on vesicles-mediated oral drug delivery for bioavailability enhancement has been properly provided. It can be concluded that VDDSs with many merits will step into an energetic arena in oral drug delivery. Keywords: vesicles, oral drug delivery, bioavailability, liposomes, niosomes, exosomes
The existence of charge-density-wave (CDW) correlations in cuprate superconductors has now been established. However, the nature of the CDW ground state has remained uncertain because disorder and ...the presence of superconductivity typically limit the CDW correlation lengths to only a dozen unit cells or less. Here we explore the field-induced 3D CDW correlations in extremely pure detwinned crystals of YBa₂Cu₃Oₓ (YBCO) ortho-II and ortho-VIII at magnetic fields in excess of the resistive upper critical field (H
c2) where superconductivity is heavily suppressed. We observe that the 3D CDW is unidirectional and possesses a long in-plane correlation length as well as significant correlations between neighboring CuO₂ planes. It is significant that we observe only a single sharply defined transition at a critical field proportional to H
c2, given that the field range used in this investigation overlaps with other high-field experiments including quantum oscillation measurements. The correlation volume is at least two to three orders of magnitude larger than that of the zero-field CDW. This is by far the largest CDW correlation volume observed in any cuprate crystal and so is presumably representative of the high-field ground state of an “ideal” disorder-free cuprate.
The predicted 2–4°C increment in temperature by the end of the 21st Century poses a threat to rice production. The impact of high temperatures at night is more devastating than day-time or mean daily ...temperatures. Booting and flowering are the stages most sensitive to high temperature, which may sometimes lead to complete sterility. Humidity also plays a vital role in increasing the spikelet sterility at increased temperature. Significant variation exists among rice germplasms in response to temperature stress. Flowering at cooler times of day, more pollen viability, larger anthers, longer basal dehiscence and presence of long basal pores are some of the phenotypic markers for high-temperature tolerance. Protection of structural proteins, enzymes and membranes and expression of heat shock proteins (HSPs) are some of the biochemical processes that can impart thermo-tolerance. All these traits should be actively exploited in future breeding programmes for developing heat-resistant cultivars. Replacement of heat-sensitive cultivars with heat-tolerant ones, adjustment of sowing time, choice of varieties with a growth duration allowing avoidance of peak stress periods, and exogenous application of plant hormones are some of the adaptive measures that will help in the mitigation of forecast yield reduction due to global warming.
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