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Abstract Fast radio bursts (FRBs) are immensely energetic millisecond-duration radio pulses. Observations indicate that nearby FRBs can be produced by old stellar populations, as suggested by the localization of the repeating source FRB 20200120E in a globular cluster of M81. Nevertheless, the burst energies of FRB 20200120E are significantly smaller than those of other cosmological FRBs. Here, we report the detection of a bright burst from FRB 20200120E in 1.1 – 1.7 GHz, with a fluence of approximately 30 Jy ms, which is more than 42 times larger than the previously detected bursts near 1.4 GHz frequency. It reaches one-third of the energy of the weakest burst from FRB 20121102A and is detectable at a distance exceeding 200 Mpc. Our finding bridges the gap between nearby and cosmological FRBs and indicates that FRBs hosted in globular clusters can be bright enough to be observable at cosmological distances.

This study was conducted to evaluate the effects of various protein sources (soybean meal, SBM; cottonseed protein, CSP; double-zero rapeseed meal, DRM) on the internal quality of refrigerated eggs. A total of 360 laying hens (32 wk of age) were randomly allotted to six treatment groups (five replicates per treatment) and fed diets containing SBM, CSP, or DRM individually or in combination with equal crude protein content (SBM-CSP, SBM-DRM, and CSP-DRM) as the protein ingredient(s). A 6×3 factorial arrangement was employed with dietary types and storage time (0 d, 2 wk, and 4 wk) as the main effects. After 12 wk of diet feeding, a total of 270 eggs were collected for egg quality determination. The egg Haugh unit (HU) in the CSP, SBM-DRM, and DRM groups were significantly lower than those in the SBM and SBM-CSP groups. The hardness and springiness of the cooked yolk in the CSP group were significantly higher than those in the other treatment groups. A lower HU, lower yolk index and higher albumen pH were observed in the DRM group compared to the SBM and SBM-CSP groups when the eggs were stored to 4 wk, and the HU was improved in the CSP-DRM group compared to the DRM group (p

The bulk Ca2CrO4 samples were synthesized under high pressure and high temperature conditions using CaO and CrO2 as starting materials. The structure of the prepared Ca2CrO4 solid is characterized by X-ray diffraction with Rietveld refinement as tetragonal structure with the space group I41/acd. The CrO6 octahedrons elongate along c axis and rotate in ab plane. DC and AC magnetic susceptibility measurement results indicate spin glass behavior at low temperature. Temperature dependence of resistivity measurement results show Ca2CrO4 is an insulator at both ambient condition and high pressure.

We study a series of LiFe_{1−x}Co_{x}As compounds with different Co concentrations by transport, optical spectroscopy, angle-resolved photoemission spectroscopy, and nuclear magnetic resonance. We observe a Fermi-liquid to non-Fermi-liquid to Fermi-liquid (FL-NFL-FL) crossover alongside a monotonic suppression of the superconductivity with increasing Co content. In parallel to the FL-NFL-FL crossover, we find that both the low-energy spin fluctuations and Fermi surface nesting are enhanced and then diminished, strongly suggesting that the NFL behavior in LiFe_{1−x}Co_{x}As is induced by low-energy spin fluctuations that are very likely tuned by Fermi surface nesting. Our study reveals a unique phase diagram of LiFe_{1−x}Co_{x}As where the region of NFL is moved to the boundary of the superconducting phase, implying that they are probably governed by different mechanisms.

The diversities in crystal structures and ways of doping result in extremely diversified phase diagrams for iron-based superconductors. With angle-resolved photoemission spectroscopy, we have systematically studied the effects of chemical substitution on the electronic structure of various series of iron-based superconductors. Beyond the Fermi-surface alteration that has been reported most often in the past, we found two more extraordinary effects of doping: (1) the site and band dependencies of quasiparticle scattering and, more importantly, (2) the ubiquitous and significant change of electronic correlation by both isovalent and heterovalent dopants in the iron-anion layer. Moreover, we found that the electronic correlation could be suppressed by applying either the chemical pressure or doping electrons but not by doping holes. Together with other findings provided here, these results complete the microscopic picture of the electronic effects of dopants, which facilitates a unified understanding of the diversified phase diagrams and resolutions to many open issues of various iron-based superconductors.

One of key issues in studying iron based superconductors is to understand how the magnetic phase of the parent compounds evolves. Here we report the systematic investigation of paramagnetic to antiferromagnetic and tetragonal to orthorhombic structural transitions of "122" SrFe2As2 parent compound using combined high resolution synchrotron Mössbauer spectroscopy and x-ray diffraction techniques in a cryogenically cooled high pressure diamond anvil cell. It is found that although the two transitions are coupled at 205 K at ambient pressure, they are concurrently suppressed to much lower temperatures near a quantum critical pressure of approximately 4.8 GPa where the antiferromagnetic state transforms into bulk superconducting state. Our results indicate that the lattice distortions and magnetism jointly play a critical role in inducing superconductivity in iron based compounds. [ABSTRACT FROM AUTHOR]

In this paper, we have demonstrated the crystallization and simultaneous formation of the nanocone structure on the 1.6µm thick amorphous silicon (a-Si) film using a one-step femtosecond laser annealing approach. The a-Si layer is crystallized after the annealing process, as confirmed from their Raman spectra. Meanwhile, the conical structures with diameters ranging from 160 nm to 1.4µm are formed upon laser beam irradiation at different fluences, as deduced from scanning electron microscope and atomic force microscope characterization. The highest absorption is achieved when the sample is irradiated with a laser fluence of 588 mJ cm-2. The developed process has potential applications in the fabrication of high efficiency and low cost Si thin-film solar cells. Moreover, the physics and mechanism involved in the laser annealing process are also discussed. [ABSTRACT FROM AUTHOR]

Cryosectioned granules were observed in microstructure, Extracellur Polymeric Substances (EPS) and metal distribution. Aerobic granules composed of pores and channels that were not plugged by EPS, with rather open structure. Microorganisms proliferated mainly on the surface of granule and on the wall of channels, carbohydrate EPS mainly distributed on the surface of granules, and protein EPS mainly distributed in the interior part of granules. Also, aerobic granules accumulated considerable calcium and phosphorus, which increase the ash solid fraction of granules and thus improve the settleability. Additionally, iron was neither temporally accumulated nor heterogeneously spatially distributed. [ABSTRACT FROM AUTHOR]

Saline wastewater is ubiquitous in industries. The present study reports the effects of salinity on the morphological properties of aerobic granules. Within a wide range of salinity from 1% to 5%, good aerobic granules were successively cultured in sequencing batch reactors (SBRs). It was found by scanning electron microscope (SEM) analysis that the granular surface turned to be smoother and more regular with increase of salinity, and under lower salinity (1%) the microbe was cocci-dominated, while under higher salinity (5%) the microbe was filaments-dominated. As a result of size distribution analysis, the granules were found to grow faster, larger and with a wider size spectrum under higher salinity. However, the porosities of the granules under the salinity of 1%, 2.5% and 5% were 0.90, 0.89 and 0.82, respectively, indicating that higher salinity may result in more compact granules. It can be concluded from this study that formation of large and compact granules is possible under salinity as high as 5% and filamentous microorganisms did not necessary lead to sludge bulking and granule breakage. [ABSTRACT FROM AUTHOR]

The blends composed of polyamide 6 (PA6) and polyamide 66 (PA66) were obtained using two different preparation methods, one of which was the melt‐mixing through a twin‐screw extruder and the subsequent injection molding; and the other, the in situ blending through anionic polymerization of ɛ‐caprolactam in the presence of PA66. For the former, there existed a remarkable improvement in toughness but a drastic drop in strength and modulus; however, for the latter, a reverse but less significant trend of mechanical properties change appeared. Various characterizations were conducted, including the analyses of crystalline morphology, crystallographic form, and crystallization and melting behaviors using polarized optical microscopy (POM), wide‐angle X‐ray diffraction (WAXD), and differential scanning calorimetry (DSC), respectively; observation of morphology of fractured surface with scanning electron microscope (SEM); measurement of glass transition through dynamic mechanical analysis (DMA); and the intermolecular interaction as well as the interchange reaction between the two components by Fourier transform infrared spectrometry (FT‐IR) and 13C solution NMR. The presence and absence of interchange reaction was verified for the in situ and melt‐mixed blends, respectively. It is believed that the transreaction resulted in a drop in glass transition temperature (Tg) for the in situ blends, contrary to an increase of Tg with increasing PA66 content for the melt‐mixed ones. And the two kinds of fabrication methods led to significant differences in the crystallographic form, spherulite size and crystalline content and perfection as well. Accordingly, it is attempted to explain the reasons for the opposite trends of changes in the mechanical properties for these two blends. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 1176–1186, 2007 [ABSTRACT FROM AUTHOR]

The structure, and the optical and electrical properties of CNx films, deposited by facing-target reactive sputtering at various N2 fractions (PN) in the gas mixture, have been studied systematically. XPS analyses indicate that N concentration increases with rising PN and reaches 28 at.% at a PN of 5%. The pure C films are mainly composed of sp3 C atoms. Increasing the N content in CNx films results in an increase of the number of sp2 C atoms and the size of aromatic sp2-hybridized C clusters, while the sp2 C remains relatively low content and rather small sized. Optical and electrical transport measurements show that all the films are semiconducting and the carrier transport is dominated by variable-range hopping between local electron states, due to the large number of defects in the films. With increasing PN, the optical band gap and room temperature resistivity increase due to the passivation of some defects in the tail states. [ABSTRACT FROM AUTHOR]

A dispersed-ozone flotation (DOF) separator was devised for a pilot study of tertiary wastewater treatment for re-use purposes. As a compact device combining coagulation, ozonation and flotation in an integrated unit, the DOF separator achieved a very high removal of SS, TOC, UV254 and colour, as well as effective inactivation of coliform and total bacteria within a short hydraulic retention time of 30 min. The finished water quality is comparable to or better than that by a conventional tertiary treatment process using coagulation, sedimentation, filtration and chlorine disinfection, and meets the quality standards for non-drinkable domestic reuse. [ABSTRACT FROM AUTHOR]

Chemical pressure induced by iso-valent doping has been widely employed to tune physical properties of materials. In this work, we report effects of chemical pressure by substitution of Sb or P into As on a recently discovered diluted magnetic semiconductor (Ba,K)(Zn,Mn)2As2, which has the record of reliable Curie temperature of 230 K due to independent charge and spin doping. Sb and P are substituted into As-site to produce negative and positive chemical pressures, respectively. X-ray diffraction results demonstrate the successful chemical solution of dopants. Magnetic properties of both K-under-doped and K-optimal-doped samples are effectively tuned by Sb- and P-doping. The Hall effect measurements do not show decrease in carrier concentrations upon Sb- and P-doping. Impressively, magnetoresistance is significantly improved from 7% to 27% by only 10% P-doping, successfully extending potential application of (Ba,K)(Zn,Mn)2As2. [ABSTRACT FROM AUTHOR]

Abstract Cancer is now considered a tumor microenvironment (TME) disease, although it was originally thought to be a cell and gene expression disorder. Over the past 20 years, significant advances have been made in understanding the complexity of the TME and its impact on responses to various anticancer therapies, including immunotherapies. Cancer immunotherapy can recognize and kill cancer cells by regulating the body's immune system. It has achieved good therapeutic effects in various solid tumors and hematological malignancies. Recently, blocking of programmed death‐1 (PD‐1), programmed death‐1 ligand‐1 (PD‐L1), and programmed death Ligand‐2 (PD‐L2), the construction of antigen chimeric T cells (CAR‐T) and tumor vaccines have become popular immunotherapies Tumorigenesis, progression, and metastasis are closely related to TME. Therefore, we review the characteristics of various cells and molecules in the TME, the interaction between PD‐1 and TME, and promising cancer immunotherapy therapeutics.

The ecosystem service value is an important concept and an index that reflects the quality of the regional ecological environment status and the measurement of the total ecological benefits. In this study, based on the characteristics of land use and the types of ecosystem in the studied area, the ecological indicators including the net primary productivity of the vegetation and the vegetation cover were selected. Landsat TM remote sensing image, ground-based observation, meteorological data and statistical data etc. were applied to establish the remote sensing-based assessment criteria and assessment model for quantitative estimation of the ecosystem service value. The established assessment criteria and model were applied to conduct the quantitative calculation on the value of the single ecosystem service and the ecosystem service value per unit area. The results indicated that during the decade of 2000–2010, with the inter-conversion of different types of land use, the total value of the ecological service in the studied area displayed a gradually decreasing trend. Among which, the values of ecological service of the cultivation land, wetland and the total ecological service were reduced by 11.92, 11.75 and 5.74%, respectively. While the values of ecological services of forest land, waters and intertidal zone were increased to certain extend. However, these increased values did not change the continuously decreasing trend of the total value of ecosystem service in the studied area. Based on these assessments, the spatially- and temporally-changing patterns of the values of ecosystem service in the studied area were analysed to reveal their intrinsic relationship between the land use and the changes in values of ecosystem service.

Maize yield is severely affected by soil salinity. In an effort to engineer maize for improved salt tolerance, embryogenic calli of maize were co-bombarded with plasmids containing Oryza sativa Na+/H+ antiporter gene (OsNHX1) and bar genes. For the molecular analysis of putative transgenic samples, PCR, Southern and Northern blots were carried out. The maize plants over-expressing OsNHX1 accumulated more biomass when grown in the presence of 200mM NaCl in greenhouse conditions. Higher Na+ and K+ content was observed in transgenic leaves than in wildtype leaves when treated with 100~200mM NaCl, while the osmotic potential and the proline content in transgenic leaves was lower than in wild-type maize. A field trial revealed that the transgenic maize plants produced higher grain yields than the wild-type plants at the vegetative growth stage. These results demonstrate that the OsNHX1 gene was successfully transferred into Zea mays, and the salt-tolerance of transgenic maize was improved by overexpression of the OsNHX1 gene.

Reports on the profiles of concentrations and radiocarbon contents of suspended particulate organic carbon and sedimentary organic carbon from an abyssal site in the northeast Pacific. Sample collection and analyses; Results of the study; Discussion of the findings.

Using lung tissues separated from 12-day-old chicken embryos, we attempted to obtain a novel population of stem cells, namely, chicken lung-derived mesenchymal stem cells (LMSCs), which exhibit spindle-like morphology. The results of colony-forming assay and population doubling assay demonstrated that LMSCs had enormous colony-forming, self-renewal, and proliferative potential. When appropriately induced, LMSCs could differentiate into osteoblasts, adypocytes, chondrocytes, and neurons; in other words, LMSCs had cross-embryonic layer differentiation potential under corresponding induction conditions. Aside from colony-forming, self-renewal, and multilineage differentiation capabilities, LMSCs were characterized by specific cell phenotypes. The results of immunohistochemistry and flow cytometry demonstrated that LMSCs consistently expressed OCT-4 - a specific gene marker expressed in pluripotent stem cells - and markers associated with MSCs such as CD29, CD73, CD90, and CD105. However, LMSCs lacked hematopoietic cell surface molecules such as CD34 and CD45. Primary LMSCs could be subcultured to passage 24 at most in vitro and karyotype analysis demonstrated that LMSCs possessed genomic stability. These unique characteristics were consistent with the characteristics of MSCs, which had been isolated from other tissues. This provides a foundation for LMSCs as a promising avenue for cellular transplantation therapy, regenerative medicine, and tissue engineering.

Lack of normal differentiation was considered as a common defect in cancer cells. MS4A12, a colon-specific gene, belongs to MS4A family that plays an important role in differentiation, proliferation and cell cycle regulation. The aim of the study was to investigate MS4A12 role in colon cancer cell differentiation and its prognostic value in colon cancer. We used sodium butyrate (BS) to set up differentiated model of colon cancer cell line LoVo. Cell differentiation was evaluated with ALP activity and E-cadherin. We used BS (4 mmol/L) inducing differentiation of LoVo cell and found after BS treated over 48h MS4A12 variant-1 (one of MS4A12 gene transcripts) as well as ALP and E-cadherin of LoVo cells were all increased significantly. When silence MS4A12 variant-1, the elevation of ALP and E-cadherin in BS-treated cells were all inhibited. Besides, after silence MS4A12 variant-1, the cells showed significant resistances to BS function of induction cell cycle arrest and apoptosis. Survival analysis used GEO datasets GSE39582 and GSE38832 that include 681 distinct colon cancer samples. Log-rank test and Cox's proportional hazards regression were applied to analyzing single and multiple prognostic variables, respectively. In early stage colon cancer, the patients with low MS4A12 expression had a poor survival (HR=1.72; p=0.036), while in advanced stage colon cancer MS412 had little prognostic value (HR=0.89; p=0.601). These results indicated MS4A12 might relate to colon cancer cell differentiation and supposed to be a risk classification marker for early stage colon cancer.