Two sets of V and Rc light curves of V789 Her and one complete set of BVRcIc light curves of V1007 Cas were observed and presented. By analyzing all these light curves together with the Sloan g′i′ ...light curves observed by Kjurkchieva et al., we determined that both systems are W-subtype contact binaries and that V789 Her is a medium contact system, while V1007 Cas is a shallow contact system. Because the two binaries show totally eclipsing primary minima, the photometric results are reliable. In addition, the light curves of the two systems are asymmetric, requiring a dark spot on the primary or the secondary component in the modeling. By compiling all available times of minimum light including literatures, SuperWASP archive and ours, we analyzed the orbital period variations. We derived that the O − C diagram of V789 Her displays a periodic oscillation whose period and amplitude are 29.2 years and 0.0179 days and the period of V1007 Cas exhibits a continuous decrease at dP/dt = −1.78( 0.09) × 10−7 days yr−1. The cyclic period modulation of V789 Her is probably attributed to the light travel time effect via a tertiary companion with very small mass. The continuous period decrease of V1007 Cas may result from the mass transfer between the two components. However, we cannot rule out the possibility of angular momentum loss because V1007 Cas shows strong magnetic activity. By analyzing the evolutionary status of the components of the two systems, we determined that they exhibit typical characteristics of other W-subtype contact binaries.
The interconversion of charge and spin currents via spin-Hall effect is essential for spintronics. Energy-efficient and deterministic switching of magnetization can be achieved when spin ...polarizations of these spin currents are collinear with the magnetization. However, symmetry conditions generally restrict spin polarizations to be orthogonal to both the charge and spin flows. Spin polarizations can deviate from such direction in nonmagnetic materials only when the crystalline symmetry is reduced. Here, we show control of the spin polarization direction by using a non-collinear antiferromagnet Mn
GaN, in which the triangular spin structure creates a low magnetic symmetry while maintaining a high crystalline symmetry. We demonstrate that epitaxial Mn
GaN/permalloy heterostructures can generate unconventional spin-orbit torques at room temperature corresponding to out-of-plane and Dresselhaus-like spin polarizations which are forbidden in any sample with two-fold rotational symmetry. Our results demonstrate an approach based on spin-structure design for controlling spin-orbit torque, enabling high-efficient antiferromagnetic spintronics.
Electron-electron (e-e) collisions can impact transport in a variety of surprising and sometimes counterintuitive ways. Despite strong interest, experiments on the subject proved challenging because ...of the simultaneous presence of different scattering mechanisms that suppress or obscure consequences of e-e scattering. Only recently, sufficiently clean electron systems with transport dominated by e-e collisions have become available, showing behaviour characteristic of highly viscous fluids. Here we study electron transport through graphene constrictions and show that their conductance below 150 K increases with increasing temperature, in stark contrast to the metallic character of doped graphene. Notably, the measured conductance exceeds the maximum conductance possible for free electrons. This anomalous behaviour is attributed to collective movement of interacting electrons, which 'shields' individual carriers from momentum loss at sample boundaries. The measurements allow us to identify the conductance contribution arising due to electron viscosity and determine its temperature dependence. Besides fundamental interest, our work shows that viscous effects can facilitate high-mobility transport at elevated temperatures, a potentially useful behaviour for designing graphene-based devices.
Immune checkpoint inhibitors in combination with tyrosine kinase inhibitors are standard treatments for advanced clear cell renal cell carcinoma (RCC). This phase III RENOTORCH study compared the ...efficacy and safety of toripalimab plus axitinib versus sunitinib for the first-line treatment of patients with intermediate-/poor-risk advanced RCC.
Patients with intermediate-/poor-risk unresectable or metastatic RCC were randomized in a ratio of 1 : 1 to receive toripalimab (240 mg intravenously once every 3 weeks) plus axitinib (5 mg orally twice daily) or sunitinib 50 mg orally once daily for 4 weeks (6-week cycle) or 2 weeks (3-week cycle). The primary endpoint was progression-free survival (PFS) assessed by an independent review committee (IRC). The secondary endpoints were investigator-assessed PFS, overall response rate (ORR), overall survival (OS), and safety.
A total of 421 patients were randomized to receive toripalimab plus axitinib (n = 210) or sunitinib (n = 211). With a median follow-up of 14.6 months, toripalimab plus axitinib significantly reduced the risk of disease progression or death by 35% compared with sunitinib as assessed by an IRC hazard ratio (HR) 0.65, 95% confidence interval (CI) 0.49-0.86; P = 0.0028. The median PFS was 18.0 months in the toripalimab–axitinib group, whereas it was 9.8 months in the sunitinib group. The IRC-assessed ORR was significantly higher in the toripalimab–axitinib group compared with the sunitinib group (56.7% versus 30.8%; P < 0.0001). An OS trend favoring toripalimab plus axitinib was also observed (HR 0.61, 95% CI 0.40-0.92). Treatment-related grade ≥3 adverse events occurred in 61.5% of patients in the toripalimab–axitinib group and 58.6% of patients in the sunitinib group.
In patients with previously untreated intermediate-/poor-risk advanced RCC, toripalimab plus axitinib provided significantly longer PFS and higher ORR than sunitinib and had a manageable safety profile
ClinicalTrials.gov NCT04394975
•Toripalimab plus axitinib provided significantly better PFS than sunitinib as a first-line treatment for advanced RCC.•A significantly higher ORR was found in patients who received toripalimab plus axitinib than those who received sunitinib.•The combination of toripalimab plus axitinib was generally well tolerated.•No new safety signals were identified in the combination outside the known safety profile of toripalimab or axitinib.
Increased generation of reactive oxygen species (ROS) leads to oxidative stress in diabetes. Catalase is a highly conserved heme-containing protein that reduces hydrogen peroxide to water and oxygen ...and is an important factor decreasing cellular injury owing to oxidative stress. Hyperglycemic conditions increase oxidative stress and angiotensinogen gene expression. Angiotensinogen conversion to angiotensin II leads to a furtherance in oxidative stress through increased generation of reactive oxygen species. In this study, we utilized mice transgenically overexpressing rat catalase in a kidney-specific manner to determine the impact on ROS, angiotensinogen and apoptotic gene expression in proximal tubule cells of diabetic animals. Proximal tubules isolated from wild-type and transgenic animals without or with streptozotocin-induced diabetes were incubated in low glucose media in the absence or presence of angiotensin II or in a high-glucose media. Our results show that the overexpression of catalase prevents the stimulation of ROS and angiotensinogen mRNA in tubules owing to elevated glucose or angiotensin II in vitro. Additionally, overexpression of catalase attenuated ROS generation, angiotensinogen and proapoptotic gene expression and apoptosis in the kidneys of diabetic mice in vivo. Our studies point to an important role of ROS in the pathophysiology of diabetic nephropathy.
Anthropogenic air pollutants such as nitrogen oxides (NO(x) = NO + NO(2)), sulfur dioxide (SO(2)), and volatile organic compounds (VOC), among others, are emitted to the atmosphere throughout the ...year from energy production and use, transportation, and agriculture. These primary pollutants lead to the formation of secondary pollutants such as fine particulate matter (PM(2.5)) and ozone (O(3)) and perturbations to the abundance and lifetimes of short-lived greenhouse gases. Free radical oxidation reactions driven by solar radiation govern the atmospheric lifetimes and transformations of most primary pollutants and thus their spatial distributions. During winter in the mid and high latitudes, where a large fraction of atmospheric pollutants are emitted globally, such photochemical oxidation is significantly slower. Using observations from a highly instrumented aircraft, we show that multi-phase reactions between gas-phase NO(x) reservoirs and aerosol particles, as well as VOC emissions from anthropogenic activities, lead to a suite of atypical radical precursors dominating the oxidizing capacity in polluted winter air, and thus, the distribution and fate of primary pollutants on a regional to global scale.
In this work, AZ61 magnesium alloy coated with NiCrAl intermediate layer with outer of Fe-based amorphous coating was fabricated by high-velocity oxy-fuel thermally spraying. Through the intermediate ...metallic coating, the traditional mismatch of Fe-based materials and magnesium substrate was overcome, exhibiting good metallurgical bonding in the interface regions. The protective magnesium alloy with Fe-based amorphous coating possesses very high hardness and excellent corrosion resistance in 3.5% NaCl solution, demonstrating by nearly ten times of hardness higher and two orders of magnitude of corrosion rate lower than the magnesium substrate. Similarly to 316L stainless steel coatings, the current Fe-based amorphous coating with a very large passive region, shows much more positive of corrosion potential and much less corrosion current density than that of sprayed Al alloy coating and ceramic coatings on magnesium alloys previously reported. The outstanding feature of the protective magnesium alloy with amorphous coating can be attributed to its unique disorder structure and uniform chemical composition, which allows a very dense passivation film formed and uniform corrosion occurred. Our findings demonstrate that Fe-based amorphous coating is a promising candidate for protecting magnesium alloys with desirable corrosion resistance for structural/functional applications.
The corrosion potential Ecorr of present Fe-based amorphous coating is much more positive than that of Al alloyed coatings, ceramic coatings and conversion coatings in 3.5% NaCl previously reported. Meanwhile, the corrosion current density icorr of Fe-based amorphous coating is much less than that of Al alloyed coatings and ceramic coatings. It should be noted that the present Fe-based amorphous coating, like 316L coating on magnesium alloys, exhibits a very broad passive region, indicating that the dense passive film on Fe-based amorphous coating surface has excellent corrosion resistance. Display omitted
•Fe-based amorphous coating was fabricated by HVOF on AZ61 magnesium alloy.•The hardness of Fe-based amorphous coating was about ten times higher than that of matrix.•The corrosion rate of the coated alloy was nearly two orders of magnitude lower than that of AZ61 alloy.
Angiotensinogen (ANG) is the sole substrate of the renin–angiotensin system (RAS). Clinical studies have shown that RAS activation may lead to hypertension, a major cardiovascular and renal risk ...factor. To delineate the underlying mechanisms of hypertension-induced nephropathy, we generated transgenic mice that overexpress rat ANG (rANG) in the kidney to establish whether intrarenal RAS activation alone can evoke hypertension and kidney damage and whether RAS blockade can reverse these effects. Transgenic mice overexpressing renal rANG were generated by employing the kidney-specific, androgen-regulated protein promoter linked to rANG cDNA. This promoter targets rANG cDNA to renal proximal tubules and responds to androgen stimulation. Transgenic mice displayed kidney-specific expression of rANG, significantly increased blood pressure (BP) and albuminuria in comparison to non-transgenic littermates. Administration of losartan (an angiotensin II (type 1)-receptor antagonist) or perindopril (an angiotensin-converting enzyme inhibitor) reversed these abnormalities in transgenic animals. Renal injury was evident on examination of the kidneys in transgenic mice, and attenuated by losartan and perindopril treatment. We conclude that the overproduction of ANG alone in the kidney induces an increase in systemic BP, proteinuria, and renal injury. RAS blockers prevent these abnormalities. These data support the role of the intrarenal RAS in the development of hypertension and renal injury.
We studied the effects on alfalfa preservation and chemical composition of the addition of different levels of malic acid and citric acid at ensiling as well as the utilization efficiency of these 2 ...organic acids after fermentation. Alfalfa was harvested at early bloom stage. After wilting to a dry matter content of approximately 40%, the alfalfa was chopped into 1- to 2-cm pieces for ensiling. Four levels (0, 0.1, 0.5, and 1% of fresh weight) of malic acid or citric acid were applied to chopped alfalfa at ensiling with 4 replicates for each treatment, and the treated alfalfa forages were ensiled for 60 d in vacuum-sealed polyethylene bags (dimensions: 200 mm × 300 mm) packed with 200 to 230 g of fresh alfalfa per mini silo and an initial density of 0.534 g/cm3. The application of malic or citric acids at ensiling for 60 d led to lower silage pH than was observed in the control silage (0% of malic or citric acids). Application of the 2 organic acids led to higher lactic acid concentration in alfalfa silage than in the control silage except with the application rate of 1% of fresh weight. Silages treated with both organic acids had lower nonprotein nitrogen concentrations than the control silages, and the nonprotein nitrogen concentrations in ensiled forages decreased with the increase in malic or citric acid application rates. The application of the 2 organic acid additives led to lower saturated fatty acid proportions and higher polyunsaturated fatty acid proportions in ensiled alfalfa than in the control silage. The amount of malic and citric acids degraded during ensiling of alfalfa was 1.45 and 0.63 g, respectively. At the application rate of 0.5% of fresh weight, residues of malic acid and citric acid in alfalfa silage were 11.1 and 13.6 g/kg of dry matter. These results indicate that including malic or citric acids at the ensiling of alfalfa effectively improved silage fermentation quality, limited proteolysis, improved fatty acid composition of the ensiled forage, and could provide animals with additional feed additives proven to promote animal performance. However, when the application rate of both organic acids reached 1%, the concentration of lactic acid in silages decreased notably. Additionally, 0.5 and 1% application rates also increased the yeast count in ensiled alfalfa.
ABSTRACT TY UMa is an F-type eclipsing binary star. Four-color light curves and radial velocities of this system were presented and simultaneously analyzed using the W-D code. It is found that TY UMa ...is a W-subtype shallow contact binary system ( ) with a mass ratio of q = 2.523. In order to explain the asymmetric light curve of this binary, a dark spot on the less massive component was employed. Our newly determined 31 times of minimum light, including those collected from the literature, have been used to analyze orbital period changes of TY UMa. The complicated period variation could be sorted into a secular period increase at a rate of days yr−1, a 51.7 yr periodic modulation (A3 = 0.0182 days), and a very small amplitude cyclic oscillation with a period of 10.0 yr (A4 = 0.0015 days). The long-term increase of the period can be explained by mass transfer from the less massive component to the more massive one. The Applegate mechanism may impossibly explain the two cyclic components in the period. The two cyclic variations are very likely caused by the light travel time effect of third and fourth components, suggesting that TY UMa is a quadruple system.
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