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The competition between forward stimulated Raman side scatter (FSRSS) and backward stimulated Raman side scatter (BSRSS) is investigated in inhomogeneous plasma using particle-in-cell (PIC) simulations. Experimental observations at the National Ignition Facility have demonstrated the significance of stimulated Raman side scatter or backscatter instability compared to two-plasmon-decay under ignition-scale conditions for various laser beam geometries. Side scatter refers to the geometry where the Raman scattered light is generated in a direction perpendicular to the local density gradient. For an obliquely incident pump, the scattered light can either copropagate (FSRSS) or counter propagate (BSRSS) with respect to the pump. Under ignition-scale conditions, linear analysis shows that both BSRSS and FSRSS are absolutely unstable (temporally growing) at higher densities ( n e ∼ 0.2 n c ), whereas at lower densities ( n e ∼ 0.1 n c ), BSRSS becomes convective with substantial gain, while FSRSS remains absolute. Two-dimensional PIC simulations demonstrate that the competition between BSRSS and FSRSS is sensitive to the density. BSRSS tends to dominate at higher densities, while FSRSS becomes dominant at lower densities. At moderate densities ( n e ∼ 0.15 n c ), FSRSS and BSRSS coexist. Furthermore, an increase in laser intensity leads to enhanced electron trapping, which kinetically strengths and then saturates BSRSS in the lower density region. [ABSTRACT FROM AUTHOR]

Time-resolved photoluminescence measurements were conducted on ZnO single crystals using two-photon (2P) excitation at low temperatures ranging from 25 to 260 K. The decay constants of various emission peaks are determined and compared between one-photon and two-photon excitations using a recently modified localized-state ensemble model. The analysis is focused on the redshift of the phonon-assisted free exciton transition energy with increasing temperature. A significantly longer radiative recombination lifetime of approximately 840 ps is observed under 2P excitation. The extended lifetime of excitons during 2P excitation is achieved through the interplay of multiple mechanisms. Photon-recycling, enabled by high absorption coefficients and total internal reflection, facilitates re-absorption and new carrier generation. Phonon scattering lowers photon energy, allowing their escape from the crystal, while exciton–polariton interactions delay photon travel, collectively contributing to the extension of exciton lifetimes. The re-absorption effect and elongated carrier lifetime observed from our work could be beneficial for applications of ZnO materials in 2P imaging, particularly of biological samples. [ABSTRACT FROM AUTHOR]

The stable manipulation, high undercooling, and thermophysical property measurement of the liquid Nb84.1Si15.9 refractory alloy were successfully achieved by the electrostatic levitation technique on board the China Space Station. By controlling the superheating temperature, a maximum liquid undercooling up to 421 K (0.18 TL) was obtained in the space environment, and two distinct solidification paths with different recalescence features were realized at metastable undercooled states. The liquid density and the ratio of specific heat to emissivity were measured in a wide temperature range from 1841 to 2346 K, which displayed linear and quadratic relations vs temperature, respectively. The liquid emissivity was further deduced from the specific heat of the liquid alloy calculated by molecular dynamics simulation. In addition, both the density and structural characteristics of the undercooled liquid alloy were also analyzed by MD calculations. [ABSTRACT FROM AUTHOR]

Objective: To construct a prediction model for fetal growth restriction (FGR) during the first trimester of pregnancy and evaluate its screening performance. Methods: This was a prospective cohort study of singleton pregnancies that underwent routine ultrasound screening at 11 to 13 + 6 weeks at the Affiliated Suzhou Hospital of Nanjing Medical University between January 2019 and April 2022. Basic clinical information, ultrasound indicators and serum biomarkers of pregnant women were collected. Fetal weight assessment was based on the fetal growth curve for the Southern Chinese population. FGR was diagnosed according to Delphi consensus criteria. Least absolute shrinkage and selection operator (lasso) regression was used to select variables for inclusion in the model. Discrimination, calibration and clinical effectiveness of the model were evaluated in training and validation cohorts. Results: A total of 1188 pregnant women were included, of whom 108 had FGR. Lasso regression identified seven predictive features, including history of maternal hypertension, maternal smoking or passive smoking, gravidity, uterine artery pulsatility index, ductus venosus pulsatility index and multiples of the median values of placental growth factor and soluble fms‐like tyrosine kinase‐1. The nomogram prediction model constructed from these seven variables accurately predicted FGR, and the area under the receiver‐operating‐characteristics curve in the validation cohort was 0.82 (95% CI, 0.74–0.90). The calibration curve and Hosmer–Lemeshow test demonstrated good calibration, and the clinical decision curve and clinical impact curve supported its practical value in a clinical setting. Conclusion: The multi‐index prediction model for FGR has good predictive value during the first trimester. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology. [ABSTRACT FROM AUTHOR]

Electron magnetic chiral dichroism (EMCD) is a high-resolution technique currently in development for quantitative magnetic measurements using transmitted electrons. However, the inevitable electron damage to materials can be a significant yet easily overlooked factor affecting the quantification accuracy. This work experimentally investigated the electron knock-on damage effects on EMCD of magnetic metals using metallic cobalt as a model. Three issues are involved in the metal-surface damage process. It was revealed that under sustained electron irradiation during spectra acquisition, gradual removal of the thin surface oxidation layer, rather than a simple continuous thickness reduction that changes the diffraction and plural scattering conditions, can lead to notable residual nonmagnetic components in EMCD spectra and may make the quantified result of the orbital-to-spin moment ratio remarkably higher than the actual value. It was, thus, proposed to pay great attention to the surface oxidation and to minimize the effect of the oxidation layer by performing electron irradiation on the target area prior to EMCD experiments. A further experiment was additionally proposed to quantify the impact of thickness reduction on the magnetic components of momentum-resolved electron energy-loss spectra and the EMCD quantification. This study advances the application of EMCD in magnetic metals. [ABSTRACT FROM AUTHOR]

Efficient regeneration of bone defects caused by disease or significant trauma is a major challenge in current medicine, which is particularly difficult yet significant under the emerging psychological stress in the modern society. Notably, the brain–bone axis has been proposed as a prominent new concept in recent years, among which autonomic nerves act as an essential and emerging skeletal pathophysiological factor related to psychological stress. Studies have established that sympathetic cues lead to impairment of bone homeostasis mainly through acting on mesenchymal stem cells (MSCs) and their derivatives with also affecting the hematopoietic stem cell (HSC)-lineage osteoclasts, and the autonomic neural regulation of stem cell lineages in bone is increasingly recognized to contribute to the bone degenerative disease, osteoporosis. This review summarizes the distribution characteristics of autonomic nerves in bone, introduces the regulatory effects and mechanisms of autonomic nerves on MSC and HSC lineages, and expounds the crucial role of autonomic neural regulation on bone physiology and pathology, which acts as a bridge between the brain and the bone. With the translational perspective, we further highlight the autonomic neural basis of psychological stress-induced bone loss and a series of pharmaceutical therapeutic strategies and implications toward bone regeneration. The summary of research progress in this field will add knowledge to the current landscape of inter-organ crosstalk and provide a medicinal basis for the achievement of clinical bone regeneration in the future. [ABSTRACT FROM AUTHOR]

The thermophysical properties of liquid Zr–V alloys covering a whole composition range were systematically measured by an electrostatic levitation technique. A series of maximum undercoolings from 150 to 386 K (0.2 TL) was achieved for 11 different liquid alloys under containerless state and radiative cooling conditions, where Zr83.5V16.5 and Zr20V80 alloys displayed the strongest undercooling ability. The densities of liquid Zr–V alloys were measured over a wide temperature range from overheated to undercooled states, and the results exhibited a linear dependence on temperature for all 11 compositions. Two typical solidification pathways were observed for hypoeutectic alloys. Except for a slowing down of decreasing tendency near a eutectic Zr57V43 alloy, the liquid densities of Zr–V alloys almost decrease linearly with increasing V content. Accordingly, the thermal expansion coefficients of Zr–V alloys were also derived from containerless measurements, and they showed an increasing tendency with V content. Since thermal radiative dominated the heat transfer process, the ratio of isobaric specific heat to hemispherical emissivity was directly deduced from the thermal balance equation, leading to a quadratic relationship with temperature. It was found that the increase of V content enhanced the ability of radiative heat dissipation below 16.5 at. % V content. [ABSTRACT FROM AUTHOR]

Ni-60%WC coatings were deposited on H13 steel substrate by laser cladding with a fibre laser. The microstructure, microhardness and wear performance of the obtained laser cladded Ni-60%WC coatings and the effect of laser power on the coefficient of friction (COF) and wear rates were analyzed. The results show that the microstructure of laser cladded Ni-60%WC coatings is mainly composed of WC and γ-Ni solid solution phases, and the hardness is decreased with an increase in laser power. The average COFs of laser cladded Ni-60%WC coatings deposited at laser power of 2100, 2500 and 2900 W are 0.51, 0.52 and 0.53, respectively; and the corresponding wear rates are 40.40 x 10-6, 86.20 x 10-6 and 120.25 x 10-6 mm³/Nm, respectively. From this it can be said that the laser power of 2100 W presents as the optimum in terms of wear resistance. The WC hard phase in the laser cladded Ni-60%WC coatings reduces the plastic deformation caused by the tribo-pair, and the wear mechanism is dominated by abrasive wear, accompanied with adhesive wear. [ABSTRACT FROM AUTHOR]

Key message: Fine-mapping of a locus on chromosome 1 of flax identified an S-lectin receptor-like kinase (SRLK) as the most likely candidate for a major Fusarium wilt resistance gene. Fusarium wilt, caused by the soil-borne fungal pathogen Fusarium oxysporum f. sp. lini, is a devastating disease in flax. Genetic resistance can counteract this disease and limit its spread. To map major genes for Fusarium wilt resistance, a recombinant inbred line population of more than 700 individuals derived from a cross between resistant cultivar ‘Bison’ and susceptible cultivar ‘Novelty’ was phenotyped in Fusarium wilt nurseries at two sites for two and three years, respectively. The population was genotyped with 4487 single nucleotide polymorphism (SNP) markers. Twenty-four QTLs were identified with IciMapping, 18 quantitative trait nucleotides with 3VmrMLM and 108 linkage disequilibrium blocks with RTM-GWAS. All models identified a major QTL on chromosome 1 that explained 20–48% of the genetic variance for Fusarium wilt resistance. The locus was estimated to span ~ 867 Kb but included a ~ 400 Kb unresolved region. Whole-genome sequencing of ‘CDC Bethune’, ‘Bison’ and ‘Novelty’ produced ~ 450 Kb continuous sequences of the locus. Annotation revealed 110 genes, of which six were considered candidate genes. Fine-mapping with 12 SNPs and 15 Kompetitive allele-specific PCR (KASP) markers narrowed down the interval to ~ 69 Kb, which comprised the candidate genes Lus10025882 and Lus10025891. The latter, a G-type S-lectin receptor-like kinase (SRLK) is the most likely resistance gene because it is the only polymorphic one. In addition, Fusarium wilt resistance genes previously isolated in tomato and Arabidopsis belonged to the SRLK class. The robust KASP markers can be used in marker-assisted breeding to select for this major Fusarium wilt resistance locus. [ABSTRACT FROM AUTHOR]

Ni-60%WC alloy coatings were prepared on the surface of a H13 steel substrate by laser cladding with a fibre laser at different laser powers. The microstructure and phases of the laser clad Ni-60%WC alloy coatings fabricated with laser power of 2100, 2500 and 2900 W were analyzed, and the electrochemical performance was measured by the potentiodynamic polarization curve (PPC) and electrochemical impedance spectroscopy (EIS). The results showed that the laser clad Ni-60%WC alloy coatings were composed of WC, W2C, and NiC phases, and the WC particles were homogeneously distributed throughout the coating cross-sections to form sound metallurgical bonding with the H13 steel substrate. The corrosion current density icorr, and polarization resistance Rp, were lowest on the laser clad Ni-60%WC alloy coating fabricated with a laser power of 2500 W. The impedance of this sample also exhibited the largest, demonstrating that the appropriate laser power will improve corrosion resistance. [ABSTRACT FROM AUTHOR]

Ni-60%WC alloy coatings were prepared on the surface of a H13 steel substrate by laser cladding with a fibre laser at different laser powers. The microstructure and phases of the laser clad Ni-60%WC alloy coatings fabricated with laser power of 2100, 2500 and 2900 W were analyzed, and the electrochemical performance was measured by the potentiodynamic polarization curve (PPC) and electrochemical impedance spectroscopy (EIS). The results showed that the laser clad Ni-60%WC alloy coatings were composed of WC, W2C, and NiC phases, and the WC particles were homogeneously distributed throughout the coating cross-sections to form sound metallurgical bonding with the H13 steel substrate. The corrosion current density icorr, and polarization resistance Rp, were lowest on the laser clad Ni-60%WC alloy coating fabricated with a laser power of 2500 W. The impedance of this sample also exhibited the largest, demonstrating that the appropriate laser power will improve corrosion resistance. [ABSTRACT FROM AUTHOR]

The effects of two-color light on stimulated Brillouin scattering (SBS) in an inhomogeneous flowing plasma have been investigated. The three-wave match of SBS is satisfied at multiple spatial locations and the multiple resonance regions occur when the two-color laser incident on an inhomogeneous flowing plasma, leading to multiple scattering of scattered light, which results in an enhancement of the reflectivity of the laser rather than a significant decrease. If the distance between the resonance points is smaller than the resonance length of SBS, the ion acoustic waves generated at different locations are coupled to each other, which enhances SBS. A model of multiple regions resonance of SBS is presented, and a one-dimensional Vlasov–Maxwell code is employed to verify the enhancement. [ABSTRACT FROM AUTHOR]

A hypothesis of the electrostatic field for the expansion of a plasma composed of two ion species into a vacuum is proposed. The solution for expansion is derived analytically and verified by numerical simulations. The expansion region is predicted to exhibit a constant velocity difference between the two ion components, which could result in ion beam instability and, thus, an increase in ion temperature. The instability, which occurs in CH plasma, is also verified theoretically and examined by particle-in-cell simulations. [ABSTRACT FROM AUTHOR]

Gravitational‐wave high‐energy Electromagnetic Counterpart All‐sky Monitor (GECAM) is a space‐borne instrument dedicated to monitoring high‐energy transients, including Terrestrial Gamma‐ray Flashes (TGFs) and Terrestrial Electron Beams (TEBs). We implemented a TGF/TEB search algorithm for GECAM, with which 147 bright TGFs, 2 typical TEBs and 2 special TEB‐like events are identified during an effective observation time of ∼9 months. We show that, with gamma‐ray and charged particle detectors, GECAM can effectively identify and distinguish TGFs and TEBs, and measure their temporal and spectral properties in detail. A very high TGF‐lightning association rate of ∼80% is obtained between GECAM and GLD360 in east Asia region. Plain Language Summary: Terrestrial gamma‐ray flashes (TGFs) and Terrestrial Electron Beams (TEBs) represent the most energetic radioactive phenomena in the atmosphere of the Earth. They reflect a natural particle accelerator that can boost electrons up to at least several tens of mega electron volts and produce gamma‐ray radiation. With novel detection technologies, Gravitational‐wave high‐energy Electromagnetic Counterpart All‐sky Monitor (GECAM) is a new powerful instrument to observe TGFs and TEBs, as well as study their properties. For example, it is difficult for most space‐borne high‐energy instruments to distinguish between TGFs and TEBs. However, we show here that, with the joint observation of gamma‐ray and charged particle detectors, GECAM can effectively identify TGFs and TEBs. GECAM can also reveal their fine features in the light curves and spectra. Key Points: During 9‐month observation, Gravitational‐wave high‐energy Electromagnetic Counterpart All‐sky Monitor (GECAM) has detected 147 bright Terrestrial Gamma‐ray Flashes (TGFs), 2 typical Terrestrial Electron Beams (TEBs), and 2 special TEB‐like eventsWith novel detector design, GECAM can effectively classify TGFs and TEBs, and reveal their fine temporal featuresWe obtained a very high TGF‐lightning association rate (∼80%) between GECAM and GLD360 in east Asia region [ABSTRACT FROM AUTHOR]

In this work, a Mg-Zn-Al-Ca alloy was processed by the combination of forward extrusion and post ECAP. The evolution and corresponding mechanism of the microstructure and mechanical properties of the Mg-5Zn-2Al-1Ca alloy were systematically investigated. As a result, the decreased-temperature ECAP processing contributes to the significant grain refinement and the production of substructures in the alloy. The minimum average grain size of 1.04 µm is achieved in the alloy after 2 passes of ECAP at 250 °C, followed by 2 passes of ECAP at 170 °C. Moreover, the texture type is changed from conventional basal fiber texture to shear texture after ECAP deformation. Consequently, the Mg-5Zn-2Al-1Ca alloy after the last 2 passes of ECAP at 170 °C exhibits excellent mechanical properties (ultimate tensile strength of ~ 350 MPa and an elongation of ~ 20%). The grain boundary strengthening and the texture strengthening as well as the Orowan strengthening effect are considered as the main contributors to the substantial increase in strength. [ABSTRACT FROM AUTHOR]

The phase selection mechanism within undercooled liquid Nb90Si10 hypoeutectic alloy was investigated by electrostatic levitation technique combined with deep neural network molecular dynamics. A stepwise-solidification procedure was conducted, where the primary phase and eutectic microstructure successively solidified from undercooled liquid alloy and undercooled residual liquid, respectively. The intermetallic phase of the eutectic structure transfers from Nb3Si to βNb5Si3 and finally into αNb5Si3 compound with the increase in liquid undercooling. The deep neural network molecular dynamic simulations have shown that the phase selection between Nb3Si and Nb5Si3 is mainly controlled by the short-range order of residual liquid, considering that the predominant short-range configuration transforms from Nb3Si-like to Nb5Si3-like structures. The αNb5Si3-like medium-range order, which is characterized by vertex-connected ⟨0,2,8,4⟩ clusters, is shown to significantly influence the competitive nucleation of the αNb5Si3 and βNb5Si3 phases. The residual liquid favors the αNb5Si3-like medium-range order rather than βNb5Si3 at large undercoolings, which explains the transformation from βNb5Si3 to αNb5Si3. [ABSTRACT FROM AUTHOR]

Due to the immature development of temperature regulation in the central nervous system, children have a weakened ability to regulate heat and are susceptible to heatstroke, which can lead to organ damage. Based on the evidence evaluation criteria of the Oxford Centre for Evidence-Based Medicine, this expert consensus group evaluated the current evidence on heatstroke in children, and formed this consensus through thorough discussion with the aim of providing reference for the prevention and treatment of heatstroke in children. This consensus includes classifications, pathogenesis, prevention measures, as well as pre-hospital and in-hospital treatment plans for heatstroke in children. [ABSTRACT FROM AUTHOR]

The mechanism of microstructure evolution during rapid solidification and the proactive regulation of phase constitution to optimize the micromechanical properties of multicomponent alloys have been the focus of research in recent years. In this paper, the evolution of microstructural growth kinetics and the formation of amorphous phase in CoCrFeNiZr0.5 alloy were achieved by melt spinning technique and electrostatic levitation coupled melt quenching. According to the theory of transient nucleation, the nucleation incubation time of Laves, FCC, Fe23Zr6 and BCC phases with undercooling during rapid solidification of the alloy was calculated. And based on this, the mechanism of phase transition in the process of regular eutectic → anomalous eutectic → nanocrystalline → amorphous composite → complete amorphous structure was discussed and explained. The growth behavior of primary and eutectic phases solidified at different undercoolings was investigated. Combined with melt quenching, the alloy melts were quenched in the superheated state, liquidus, undercooled state and recalescence process. Multiple microstructures, including amorphous structure, amorphous plus nano-eutectic, gradient nano-eutectic and composite structure of primary Laves phase, along with primary eutectic plus secondary quenched eutectic structures were obtained, respectively. Moreover, the shear band and free volume theory were applied to explain the deformation behavior and the discrepant mechanical performance between amorphous composites and amorphous structures. The formation of quenched nano-eutectic and amorphous structure not only improves the hardness of the alloy, but also enhances the fracture toughness. [ABSTRACT FROM AUTHOR]

Competition among the two-plasmon decay (TPD) of backscattered light of stimulated Raman scattering (SRS), filamentation of the electron-plasma wave (EPW) and forward side SRS is investigated by two-dimensional particle-in-cell simulations. Our previous work [K. Q. Pan et al., Nucl. Fusion 58, 096035 (2018)] showed that in a plasma with the density near 1/10 of the critical density, the backscattered light would excite the TPD, which results in suppression of the backward SRS. However, this work further shows that when the laser intensity is so high (> 1016 W/cm²) that the backward SRS cannot be totally suppressed, filamentation of the EPW and forward side SRS will be excited. Then the TPD of the backscattered light only occurs in the early stage and is suppressed in the latter stage. Electron distribution functions further show that trapped-particle-modulation instability should be responsible for filamentation of the EPW. This research can promote the understanding of hot-electron generation and SRS saturation in inertial confinement fusion experiments. [ABSTRACT FROM AUTHOR]

Enterotoxigenic E. coli is an important zoonotic pathogen causing diarrhea in humans and newborn animals. α - (1,2) fucosyltransferase 2 (FUT2) is closely associated with the formation of pathogenic receptors of Enterotoxigenic E. coli. Codon usage bias analysis can help to understand better the molecular mechanisms and evolutionary relationships of a particular gene. To understand the codon usage pattern of the FUT2 gene, FUT2 gene coding sequences of nine species were selected from the GenBank database for calculating the nucleotide composition (GC content) and genetic indices, including an adequate number of codons, relative synonymous codon usage, and relative codon usage bias using R software, to analyze codon usage bias and base composition in FUT2 gene from different species. The results showed that the codon usage of the FUT2 gene in other species was affected by GC bias, mainly GC frequency at the third position of codon (GC3). Most of the optimal codons were biased towards the G/C-ending types. GCC, CUG, UCC, GUG, and AUC showed the highest relative synonymous codon usage value among different species belonging to the most dominant codons. The usage characteristic of the codons for the FUT2 gene in Sus scrofa was similar to that of Bos taurus; Homo sapiens was similar to Pan troglodytes. An adequate number of codons was significantly negatively correlated with GC3. The relatively higher frequency of optimal codons implied that FUT2 genes from different species had a strong bias in codon usage. [ABSTRACT FROM AUTHOR]

[FeIII(OMe)(Hedtb)](ClO4)3·6.5CH3OH (1) and [FeIII(On-Bu)(Hedtb)](ClO4)3·3n-BuOH (2) (edtb = N,N,N′,N′-tetrakis[(2-benzimidazolyl)methyl]-1,2-ethanediamine) were prepared and display lipoxygenase activity. X-ray crystallography reveals that the FeIII centers in complexes 1 and 2 are ligated to three nitrogens of benzimidazole and two alkylamine nitrogen atoms from the edtb ligand, with a terminal alkyoxyl group occupying the sixth position. Complexes 1 and 2 both possess a FeIII–OR center (R = Me, 1; n-Bu, 2) with Fe–O bond distances of 1.799(3) Å and 1.789(5) Å, respectively. The UV-Vis spectra and electrochemical properties of the complexes were recorded. Both complexes have strong absorption peaks at around 375 nm and display lipoxygenase activity. [ABSTRACT FROM AUTHOR]

Stimulated Raman scattering can occur near the quarter critical density in direct-drive fusions, and the frequency of Raman-scattered light is about half of the incident light frequency. The second harmonic of the Raman-scattered light can be produced due to the inhomogeneity density profile. It can serve as the seed of stimulated Brillouin scattering (SBS). When the second harmonic of stimulated Raman-scattered light propagates against the incident light, some components will match the frequency of backward SBS, and SBS is induced. Thus, SBS could be greatly enhanced. [ABSTRACT FROM AUTHOR]

The schweinfurthin family of natural compounds exhibit a unique and potent differential cytotoxicity against a number of cancer cell lines and may reduce tumor growth in vivo. In some cell lines, such as SF-295 glioma cells, schweinfurthins elicit cytotoxicity at nanomolar concentrations. However, other cell lines, like A549 lung cancer cells, are resistant to schweinfurthin treatment up to micromolar concentrations. At this time, the precise mechanism of action and target for these compounds is unknown. Here, we employ RNA sequencing of cells treated with 50 nM schweinfurthin analog TTI-3066 for 6 and 24 h to elucidate potential mechanisms and pathways which may contribute to schweinfurthin sensitivity and resistance. The data was analyzed via an interaction model to observe differential behaviors between sensitive SF-295 and resistant A549 cell lines. We show that metabolic and stress-response pathways were differentially regulated in the sensitive SF-295 cell line as compared with the resistant A549 cell line. In contrast, A549 cell had significant alterations in response genes involved in translation and protein metabolism. Overall, there was a significant interaction effect for translational proteins, RNA metabolism, protein metabolism, and metabolic genes. Members of the Hedgehog pathway were differentially regulated in the resistant A549 cell line at both early and late time points, suggesting a potential mechanism of resistance. Indeed, when cotreated with the Smoothened inhibitor cyclopamine, A549 cells became more sensitive to schweinfurthin treatment. This study therefore identifies a key interplay with the Hedgehog pathway that modulates sensitivity to the schweinfurthin class of compounds. [ABSTRACT FROM AUTHOR]

To provide reference basis for the apoptosis of breast cancer cells and the carcinogenesis of breast cancer, the effects of 7,12-dimethylbenz(a)anthracene on apoptosis regulators Fas ligand and B-cell lymphoma-2 were investigated. In this study, 62 female C57BL/6 mice aged from 4 w to 6 w were randomly divided into control group and test group, with 31 mice in each group. The test group was given 7,12-dimethylbenz(a) anthracene solution by gavage at a dose of 50 mg/kg and the control group was given normal saline of equal volume. On the 2nd d after the experiment, all the mice were killed by cervical dislocation. The results showed that after hematoxylin-eosin staining, the tumor cells in the test group were stacked up to form a substantial structure. The expression level of Fas ligand protein in the control group was greatly lower than that in the test group and the positive rate was 20.25 %, which was greatly lower than that of 89.65 % in the test group (p<0.01). The expression level of B-cell lymphoma-2 protein in the mammary gland tissues of mice in the test group was greatly higher than that of the control group and its positive rate was 87.96 %, which was greatly higher than that of 31.48 % in the control group (p<0.01). The expression levels of Fas ligand messenger ribonucleic acid in the mammary gland tissues of mice in the test group and control group were 5.82±4.37 and 1.27±0.12, respectively and there was a statistically obvious difference (p<0.05). The messenger ribonucleic acid expression levels of B-cell lymphoma-2 in the test group and the control group were 18.97±2.65 and 2.02±0.54, respectively, and there was an extremely obvious difference (p<0.01). The apoptosis rate of mammary gland cells in the test group was (19.79±3.53) % and that in the control group was (2.93±0.28) % and there was an extremely obvious difference (p<0.01). It indicated that 7,12-dimethylbenz(a)anthracene inhibited the apoptosis of breast cancer cells by regulating the upregulation of Fas ligand and B-cell lymphoma-2 expression. [ABSTRACT FROM AUTHOR]

Most species in the genus Cypripedium (Cypripedioideae) produce trap flowers, making it a model lineage to study deceptive pollination. Floral attractants in most species studied appear to target bee species of different sizes. However, more recent publications report fly pollination in some subalpine species, suggesting novel suites of adaptive floral traits.Cypripedium lichiangense (section Trigonopedia) is an endangered subalpine species endemic to the Hengduan Mountains, China. We observed and analysed its floral traits, pollinators and breeding systems over 2 years in situ and in the lab.Cypripedium lichiangense was visited by females of Ferdinandea cuprea (Syrphidae). The pollinia were carried dorsally on the fly thoraces. The eggs of this fly were frequently found in the saccate labellum and on other floral organs, suggesting brood‐site mimesis. The orchid is self‐compatible, but cross‐pollination produces more viable embryos.We propose a new mode of floral mimesis, humus‐rich oviposition site mimicry, for C. lichiangense. Compared with the mimesis of aphid colonies attracting syrphid pollinators (subfamily Syrphinae), whose larvae are entomophagic, as reported in some Paphiopedilum species (Cypripedioideae), pollination by deceit in C. lichiangense represents a distinct and separate mode of exploitation of another saprophagic (or phytophagic) larvae syrphid lineage in the subfamily Eristalinae and appears to indicate diversity of pollination strategies in Section Trigonopedia of Cypripedium. However, this new brood‐site mimesis seems to be less attractive to pollinators. As a possible adaptation to the weak attracted pollination strategy, this plant species has a long flowering period and extended lifespan of individual flowers to ensure reproductive success. [ABSTRACT FROM AUTHOR]

The temporal evolution of Langmuir waves is presented with two-dimensional electrostatic Vlasov simulations. In a muti-wavelength system, trapped electrons can generate sidebands including longitudinal, transverse, and oblique sidebands. We demonstrated that oblique sidebands are important decay channels of Langmuir waves, and the growth rate of oblique sidebands is smaller than that of longitudinal sidebands but higher than that of transverse sidebands. When the amplitudes of sidebands are comparable with that of a Langmuir wave, vortex merging occurs following the broadening of longitudinal and transverse wavenumbers, and finally the system is developed into a turbulent state. In addition, the growth of sidebands can be depicted by the nonlinear Schrödinger model [Dewar–Rose–Yin (DRY) model] with non-Maxwellian Landau damping. The theoretical results show the significance of nonlinear frequency shift in the evolution of Langmuir waves. The growth rates of sidebands in the DRY model are in qualitative agreement with Vlasov simulations. [ABSTRACT FROM AUTHOR]

In recent years, due to the development of the automobile industry, there are more and more waste car tires, and the reuse of waste tires has become an urgent problem to be solved. In this study, the crushed rubber of waste automobile tires is used to modify asphalt to prepare rubber-modified asphalt, which can not only solve the problem of using waste tires but also effectively improve the performance of asphalt pavement. This study defines four modified asphalts with different rubber powder content, which are defined as 1#, 2#, 3#, and 4#, respectively. The performance difference between the four modified asphalts and the base asphalt was compared through experiments to illustrate the advantages of rubber-modified asphalt. The four selected rubber asphalts and base asphalt are subjected to the viscous toughness test, apparent viscosity test, DSR test, and BBR test to determine the high- and low-temperature characteristics of rubber asphalt. The analysis of experimental data shows that rubber-modified asphalt can effectively improve the low-temperature performance of the asphalt, make the asphalt have better toughness, and also improve the high-temperature shear resistance of the asphalt. Finally, it is determined that adding 10% rubber powder to the base asphalt has the best effect. [ABSTRACT FROM AUTHOR]

Background: Selenium (Se) is an essential trace element to higher plants, animals and humans, but low Se levels are a global public health concern. Seed priming has become a basic strategy for the production of Se-riched agricultural products, but its application is still not clear in the production of Se-enrich alfalfa, hence this study was conducted for the production of Se-enriched alfalfa by seed priming with different concentrations and time on seed vigour. Methods: Seeds were primed with 0, 0.5, 1.0, 2.0, 4.0 and 8.0 mmol L-1 of sodium selenite solution for 0, 3, 6, 9 and 12 h at 20°C and their germination percentage, germination index, seedling vigour index and mean germination time were analyzed. Result: Seed vigour of alfalfa was improved by priming with low selenium (Se) concentration (0.5 and 1.0 mmol L-1), but was inhibited by high Se concentration (> 2.0 mmol L-1). Hence, it must be necessary to carefully select appropriate concentration and time for the application of Se priming in alfalfa seeds. The optimal manner of Se priming in alfalfa seeds might be at 1.0 mmol L-1 concentration for 9 h. [ABSTRACT FROM AUTHOR]

To evaluate the impacts of guanidinoacetic acid (GAA) and coated folic acid (CFA) on growth performance, nutrient digestion and hepatic gene expression, fifty-two Angus bulls were assigned to four groups in a 2 × 2 factor experimental design. The CFA of 0 or 6 mg/kg dietary DM folic acid was supplemented in diets with GAA of 0 (GAA−) or 0·6 g/kg DM (GAA+), respectively. Average daily gain (ADG), feed efficiency and hepatic creatine concentration increased with GAA or CFA addition, and the increased magnitude of these parameters was greater for addition of CFA in GAA− diets than in GAA+ diets. Blood creatine concentration increased with GAA or CFA addition, and greater increase was observed when CFA was supplemented in GAA+ diets than in GAA− diets. DM intake was unchanged, but rumen total SCFA concentration and digestibilities of DM, crude protein, neutral-detergent fibre and acid-detergent fibre increased with the addition of GAA or CFA. Acetate:propionate ratio was unaffected by GAA, but increased for CFA addition. Increase in blood concentrations of albumin, total protein and insulin-like growth factor-1 (IGF-1) was observed for GAA or CFA addition. Blood folate concentration was decreased by GAA, but increased with CFA addition. Hepatic expressions of IGF-1, phosphoinositide 3-kinase, protein kinase B, mammalian target of rapamycin and ribosomal protein S6 kinase increased with GAA or CFA addition. Results indicated that the combined supplementation of GAA and CFA could not cause ADG increase more when compared with GAA or CFA addition alone. [ABSTRACT FROM AUTHOR]

Spatially resolved Raman light scattering experiments were performed on a zinc-blende GaN/GaAs heterostructure with confocal micro-Raman scattering technique under the backscattering geometric configuration. By varying the illumination spot locations across the heterostructure interface, we found that the Raman light scattering spectral features change remarkably. The interface effect on the GaAs substrate manifested as a much broader lineshape of the transverse optical (TO) phonon mode. Two kinds of broadening mechanisms, namely, spatial correlation induced wave-vector relaxation effect and lattice-mismatch strain + compositional intermixing effect, have been identified. The former leads to the broadening of the TO mode at the low-energy side, whereas the latter accounts for the broadening at the high-energy side. The diffuse light scattering from the highly defective nucleation layer of GaN was found to produce a broad scattering background of the GaN TO mode. The methodology and conclusions of the present work could be applicable to Raman spectroscopic studies on other material interfaces. [ABSTRACT FROM AUTHOR]

The structure, thermodynamic and dynamic properties of normal and metastable liquid Ni2xFe50−xCo50−x alloys were systematically investigated by combining electrostatic levitation (ESL) experiments and molecular dynamics (MD) simulations. Their composition dependence and mutual interaction were explored in detail. The actual densities of liquid Ni90Fe5Co5, Ni80Fe10Co10, Ni70Fe15Co15 and Ni60Fe20Co20 alloys were measured by ESL experiments in a wide temperature range. The simulated densities of these liquid alloys are in good agreement with the corresponding experimental data. The thermodynamic properties show that all these alloys exhibit a negative excess volume and mixing enthalpy. Meanwhile, their pair distribution functions indicate that Fe and Co atoms easily bond with Ni atoms and have a similar characteristic to each other if compared with Ni atoms. Furthermore, the structure factors validate that there exist icosahedral short-range and medium-range orders of Ni-Ni, Fe-Fe, Fe-Co and Co-Co bonds in these liquid alloys. Additionally, the solute diffusion properties reveal that the correlation between dynamic behavior and alloy composition is determined by the diffusion of Fe and Ni atoms. [ABSTRACT FROM AUTHOR]

We investigate the behaviour of backward stimulated Raman scattering (BSRS) in inhomogeneous plasma with a transverse external magnetic field via 1D and 2D particle-in-cell simulations and theoretical analysis. The external magnetic field causes nonlinear damping of large-amplitude electron plasma waves (EPWs), and significantly limits the reflectivity of stimulated Raman scattering (SRS) even if is very weak. For a single resonance point, limits the kinetic nonlinear frequency shift, impedes the autoresonance behaviour of SRS, and narrows the resonance region. We also exhibit distorts the distribution function of electrons evidently, and alters the wavefronts of EPWs in high dimensional cases. The simulation results indicate a moderate can significantly reduce the trapped electron induced gain of SRS reflectivity, and make the BSRS reflectivity stay at its linear convective saturation level steadily. [ABSTRACT FROM AUTHOR]

The influence of sinusoidal density modulation on stimulated Raman scattering (SRS) reflectivity in inhomogeneous plasmas is studied using three-wave coupling equations, fully kinetic Vlasov simulations, and particle-in-cell (PIC) simulations. Through a numerical solution of the three-wave coupling equations, we find that the sinusoidal density modulation is capable of inducing absolute SRS even though the Rosenbluth gain is smaller than π, and we describe a region of modulational wavelength and amplitude in which absolute SRS can be induced, which agrees with earlier studies. The average reflectivity obtained by the Vlasov simulations has the same trend as the growth rate of absolute SRS obtained from the three-wave equations. Instead of causing absolute instability, a modulation wavelength shorter than the basic gain length can suppress the inflation of SRS through harmonic waves. In addition, the PIC simulations qualitatively agree with our Vlasov simulations. Our results offer an alternative explanation for high reflectivity in experimental underdense plasmas, which is due to long-wavelength modulation, and a potential method to suppress SRS using short-wavelength modulation. [ABSTRACT FROM AUTHOR]

The fast and slow waves in multi-ion species collisionless plasmas have been widely studied, but the collision effect on ion acoustic waves is a difficult problem. In this paper, plasmas with azimuthal symmetry velocity distribution in different collisional regimes are studied by eigenvalue solution of the linearized Fokker–Planck equation. The frequency, damping rate and distribution function from the solutions are consistent with the analytical result in collisionless limit. For the fast wave, the damping rate agrees well with the prediction of both fluid theory in collision limit and kinetic theory in collisionless limit. But for the slow wave, the frequency and damping rate predicted by fluid theory are not accurate. In two-ion species plasmas, the light and heavy ion density perturbation phases of two-ion species are the same for the fast wave, but opposite for the slow wave. Polytropic index of C5H12 plasmas is also calculated, which is simply affected by mean-free paths of ions for the fast wave, but affected by multiple factors, such as mean-free paths, heat transfer and the opposite phases for the slow wave. [ABSTRACT FROM AUTHOR]

Background: Accurate and robust pathological image analysis for colorectal cancer (CRC) diagnosis is timeconsuming and knowledge-intensive, but is essential for CRC patients’ treatment. The current heavy workload of pathologists in clinics/hospitals may easily lead to unconscious misdiagnosis of CRC based on daily image analyses. Methods: Based on a state-of-the-art transfer-learned deep convolutional neural network in artificial intelligence (AI), we proposed a novel patch aggregation strategy for clinic CRC diagnosis using weakly labeled pathological whole-slide image (WSI) patches. This approach was trained and validated using an unprecedented and enormously large number of 170,099 patches, > 14,680 WSIs, from > 9631 subjects that covered diverse and representative clinical cases from multi-independent-sources across China, the USA, and Germany. Results: Our innovative AI tool consistently and nearly perfectly agreed with (average Kappa statistic 0.896) and even often better than most of the experienced expert pathologists when tested in diagnosing CRC WSIs from multicenters. The average area under the receiver operating characteristics curve (AUC) of AI was greater than that of the pathologists (0.988 vs 0.970) and achieved the best performance among the application of other AI methods to CRC diagnosis. Our AI-generated heatmap highlights the image regions of cancer tissue/cells. Conclusions: This first-ever generalizable AI system can handle large amounts of WSIs consistently and robustly without potential bias due to fatigue commonly experienced by clinical pathologists. It will drastically alleviate the heavy clinical burden of daily pathology diagnosis and improve the treatment for CRC patients. This tool is generalizable to other cancer diagnosis based on image recognition. [ABSTRACT FROM AUTHOR]

Background: Accurate and robust pathological image analysis for colorectal cancer (CRC) diagnosis is time-consuming and knowledge-intensive, but is essential for CRC patients' treatment. The current heavy workload of pathologists in clinics/hospitals may easily lead to unconscious misdiagnosis of CRC based on daily image analyses.Methods: Based on a state-of-the-art transfer-learned deep convolutional neural network in artificial intelligence (AI), we proposed a novel patch aggregation strategy for clinic CRC diagnosis using weakly labeled pathological whole-slide image (WSI) patches. This approach was trained and validated using an unprecedented and enormously large number of 170,099 patches, > 14,680 WSIs, from > 9631 subjects that covered diverse and representative clinical cases from multi-independent-sources across China, the USA, and Germany.Results: Our innovative AI tool consistently and nearly perfectly agreed with (average Kappa statistic 0.896) and even often better than most of the experienced expert pathologists when tested in diagnosing CRC WSIs from multicenters. The average area under the receiver operating characteristics curve (AUC) of AI was greater than that of the pathologists (0.988 vs 0.970) and achieved the best performance among the application of other AI methods to CRC diagnosis. Our AI-generated heatmap highlights the image regions of cancer tissue/cells.Conclusions: This first-ever generalizable AI system can handle large amounts of WSIs consistently and robustly without potential bias due to fatigue commonly experienced by clinical pathologists. It will drastically alleviate the heavy clinical burden of daily pathology diagnosis and improve the treatment for CRC patients. This tool is generalizable to other cancer diagnosis based on image recognition. [ABSTRACT FROM AUTHOR]

Aims: Reproduction can induce maternal oxidative stress, and resveratrol is able to alleviate oxidative stress. This study aimed to investigate the protective effects of resveratrol supplementation in mice during pregnancy and lactation. Methods and Results: Pregnant mice were randomly divided into three groups: (i) Pure water (Con); (ii) Cellulose sodium dissolves with 20 mg kg−1 resveratrol (R1) and (iii) Cellulose sodium dissolves with 40 mg kg−1 resveratrol (R2). The experiment starts at pregnancy and ends at weaning. The results showed that resveratrol increased mammary cell proliferation and the mRNA expressions of UDP glucuronosyltransferase family 1 member A1 (UGT1A1) and cytochrome P450 proteins (CYP1A1), while decreased superoxide dismutase, extracellular (SOD3) in the mammary gland. Further study showed that resveratrol promoted the mRNA expressions of genes involved in mitophagy, such as transcription factor Eβ (Tfeβ), Bcl1lc3β, homosapiens microtubule‐associated protein 1 light‐chain 3 beta (Map1lc3β), Parkin, sequestosome1 (p62), autophagy‐related protein (Atg5) and Beclin‐1 (Becn1) in the mammary gland. Moreover, resveratrol increased the abundances of some intestinal microbial species. 40 mg kg−1 resveratrol significantly increased the contents of Acidobacteri, unidentified acidbacteria, Bacilales, Staphylococcaceae and Staphylococcus at phylum, class, order, family and genus level respectively. Conclusion: Our results indicate that resveratrol supplementation may promote mammary cell proliferation and antioxidant ability through mitophagy and regulating gut microbiota in pregnant mice. Significance and Impact of the Study: Current study proved that resveratrol could affect mammary cell proliferation and antioxidation capacity during pregnancy and lactation in mice for the first time. The underlying mechanisms may be related to mitophagy and gut microbiota. [ABSTRACT FROM AUTHOR]

The effects of the subwavelength nanowire target on the enhanced laser absorption, heating of electrons, and acceleration and control of energetic ions are investigated by using two-dimensional particle-in-cell simulations. Compared with the flat target, the conversion efficiency and acceleration of target normal sheath acceleration can be improved remarkably. In the condition considered in this paper, the conversion efficiency from the laser to electrons can be increased by about four times (14.74% to 65.78%), and the cutoff energy of electrons can be raised by 1.5 times. Furthermore, the cutoff energies of both protons and carbon ions are increased by almost two times. The dependence of this effect for different nanowire widths is discussed by numerical simulations. It is found that the efficiency from the laser to electrons reaches the highest value when the nanowire width is d = 0.2 μ m. The optimum width for C6+ ions is d = 0.3 μ m , while d = 0.8 μ m is better for proton acceleration. Thus, the laser absorption, electron heating, and ion acceleration could be controlled by selecting the width of subwavelength nanowires. [ABSTRACT FROM AUTHOR]

Enhanced stimulated Brillouin scattering and stimulated Raman scattering are shown in comparable-mass plasma by considering charge state through a simplified theoretical model and particle-in-cell simulations. We present a more general dispersion relation of plasma wave with arbitrary mass ratio and charge state compared to the previous electron–positron plasma study. Further, the ion-bulk mode is responsible for Brillouin amplification from kinetic analysis. Higher intensities of seed laser pulse amplification through stimulated Brillouin scattering are observed in βZ = 1 type plasmas and β = 1 type plasmas as Z increases; the former is caused by kinetic effects, while the latter is due to the higher growth rates of instability. Our results will have potential application in pulse amplification in the comparable-mass plasmas with charge state Z > 1, such as plasma of. [ABSTRACT FROM AUTHOR]

Phase space vortex merging in electron plasma waves is researched by applying a periodically changing electric field in plasma space with Maxwellian velocity distribution. The pump electric field excites the electron plasma wave with large amplitude and electron phase space vortices are formed. The electron plasma wave can be transited to longer wave modes through vortex merging processes. Excepting the fundamental mode of electron plasma waves, two or more modes appear and grow exponentially before vortex merging. After merging, another mode replaces the initial pumping wave as the strongest wave mode. It is verified that the growth of this new strong mode is related to trapping particle instability. Vortex merging is one of the saturation mechanisms of trapped particle instability. [ABSTRACT FROM AUTHOR]

The thermophysical properties of liquid Zr-Fe alloys were experimentally measured by an electrostatic levitation technique. A series of undercoolings from 45 K to 410 K were achieved for these liquid alloys in the natural radiation cooling process. Since the experiments were conducted in high-vacuum and containerless conditions, the ratio of the specific heat to the hemispherical emissivity was deduced and showed a quadratic relationship with temperature. For the eutectic Zr76Fe24 alloy, the hypercooling of 306 K and hemispherical emissivity were derived theoretically due to its low liquidus temperature and scarce volatilization. Through digital image processing, the alloy densities were measured, and the results depended linearly on temperature over a wide temperature range covering both superheated and undercooled liquid states. The absolute value of the temperature coefficient tended to increase with increasing Fe contents, indicating that the liquid density sensitivity increased with increasing Fe contents. The surface tension and viscosity were also determined by a drop oscillation method under the electrostatic levitation condition. [ABSTRACT FROM AUTHOR]

In supersonic flowing plasmas, the auto-resonant behavior of ion acoustic waves driven by stimulated Brillouin backscattering is self-consistently investigated. A nature of absolute instability appears in the evolution of the stimulated Brillouin backscattering. By adopting certain form of incident lights combined by two perpendicular linear polarization lasers or polarization rotation lasers, the absolute instability is suppressed significantly. The suppression of auto-resonant stimulated Brillouin scattering is verified with the fully kinetic Vlasov code. [ABSTRACT FROM AUTHOR]

A new saturation mechanism, beam plasma instability with trapped electrons resulting in saturation of stimulated Raman backscattering (SRBS), is presented. The beam plasma instability can be excited due to interaction between beam electrons and background electrons and it will produce a new mode. Here, the trapped electrons can be considered as beam electrons with velocity vp (phase velocity of the plasma wave) and density nt (density of the trapped electrons normalized by nc, nc is the critical density for the incident laser light). This new mode will induce a sinusoidal density modulation and then this modulation will produce harmonic wave with modulation wave-number period δk to enhance this new mode. As reported previously, the density modulation can increase Landau damping of the plasma wave and decrease the resonant region where SRBS occurs. Therefore, SRBS will saturate due to beam plasma instability induced by the trapped electrons. [ABSTRACT FROM AUTHOR]