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Let C=(C,E,s)be an extriangulated category. In this paper, we give the notion of ideal balanced pairs in Cand some equivalent characterizations of ideal balanced pairs. We show that there is a one-to-one correspondence between balanced pairs and ideal balanced pairs satisfying certain conditions when Cis of a negative first extension. We also prove that there is a bijective correspondence between ideal balanced pairs (ℐ,J) and additive subfunctors F⊆Ewith enough projective morphisms and enough injective morphisms in C.

To distinguish banana ripening stages based on their volatile organic compounds (VOCs) and aroma properties, banana samples with different ripening processes were divided into five stages (green ripe, yellow ripe, browning stage 1, browning stage 2, and browning stage 3) based on digital images and the K-means clustering algorithm, and their VOCs were determined. A total of 35 VOCs were identified using solid-phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS), including aldehydes, alcohols, esters, ketones, terpenoids, and other alkanes. Ten VOCs belonging to 7 aroma categories (pineapple, banana, fruity, apple, grass, sweet, and green aromas) were distinguished according to the radar fingerprint chart. Principal component analysis (PCA) and linear discriminant analysis (LDA) were used separately to analyze the differences and establish classification models based on the relative content of banana peel VOCs. For bananas at different ripening stages, PCA and LDA provided good discrimination accuracy based on the dataset. Therefore, banana peel VOCs and their aroma characteristics can serve as effective indices for evaluating the banana ripening stage.

Antibiotic resistance is a growing challenge and a major public health concern worldwide. Nanoplastics, which are ubiquitous in aquatic ecosystems, may cause a potential risk to the dissemination of antibiotic resistance genes (ARGs) in bacteria. However, the extent to which nanoplastics can cause an increase in antibiotic resistance by the regulation of the conjugative transfer of ARGs within bacteria remains unknown. In this study, polystyrene nanoplastics (PSNPs) with small sizes (S-PSNPs) and large sizes (L-PSNPs) were applied at a wide concentration range of 0.1–200 mg L−1to investigate their effects on plasmid-mediated conjugative transfer of ARGs between E. colistrains. The results revealed that S-PSNPs significantly enhanced the conjugative transfer frequency of the RP4 plasmid up to 1.51 fold at the 10 mg L−1exposure level compared with untreated cells; however, L-PSNPs generally caused no significant effect. We also employed multiple approaches to reveal the mechanisms, which demonstrated that PSNPs facilitated the conjugative transfer of ARGs by inducing excessive reactive oxygen species and oxidative stress, increasing cell membrane permeability, up-regulating the expression of mating pair formation genes (trbBpand traF) and DNA transfer and replication genes (trfApand traJ), and down-regulating the global regulatory gene expression (korA, korB, and trbA). These findings provide insights regarding the contributions and the underlying mechanisms of nanoplastics to the dissemination of ARGs, and are helpful for the evaluation of the public health and environmental and ecological risks caused by nanoplastics.

The biggest sand-dust storm from Mongolia in the past decade swept across northern China on March 15, 2021. Before this sudden outbreak, the number of sand-dust storms in northern China had been decreasing for 50 years. Wind and sand resources are the two key elements for sand-dust storms to occur. With an abrupt shift to a drier and hotter climate in the past 20 years over inner East Asia providing more sand resources and an increasing wind speed trend, the sand-dust storm in 2021 may herald the beginning of an era with more sand-dust storms. To answer whether increasing wind speed will significantly influence the sand-dust storm frequency, this study analyzed the relationship between the annual average wind speed and sand-dust storm days in northern China and Mongolia, finding that they have a high correlation (R= 0.94) in northern China and a moderate correlation (R= 0.41) in Mongolia. We further found that the wind speed during sand-dust storms also decreased, which further supports that the decrease of sand-dust storm frequency is mainly reasoned from the decrease of wind speed. Therefore, as the wind speed increases, the sandstorm frequency can increase as well, which has been seen clearly in Mongolia but may be just beginning in China.

•Floating photovoltaics around turbines increase wind farm production by 7 times.•Floating photovoltaics cover 17 % area, doubling wind farm annual output.•Floating photovoltaics cover 11 % area, boosting 76 % power with the same investment.•Offshore wind and solar complement on monthly scales, especially in high latitudes.

Lead halide perovskite anion exchange reactions tend to be spontaneous and rapid. To achieve precise control of anion exchange and modulate the bandgaps of perovskites to meet the demands in full-color displays, a laser-induced liquid-phase anion exchange method is developed in this paper. CsPbBr3perovskites embedded in a polymer matrix are converted to CsPb(BrxCl1–x)3and CsPb(BrxI1–x)3perovskites, realizing the shift from green fluorescence to blue and red fluorescence. By changing the laser parameters, the anion exchange extent and luminescence wavelength are precisely tuned, with the maximum tuning wavelength range of 431–696 nm. Due to the focusing properties of the laser, the spatial position of anion exchange can be precisely controlled, which is significant for realizing fast and accurate patterning without masks. Based on this method, blue patterns with different light-emitting wavelengths are fabricated. RGB three-color patterns on a single perovskite composite film are successfully prepared by further replacement of halogen ions. More importantly, the polymer matrix provides ultraflexibility and good stability for the films; even if the composite films are arbitrarily folded or repeatedly bent, they can still maintain good luminous intensity. This method will show great potential in the field of flexible, full-color displays.

In this study, Mg–Y–Sm–Zn–Zr samples were prepared using the selective laser melting technique. The influence of process parameters on the densification and mechanical properties of samples was systematically studied from a single-melt track to double melt tracks to block, and the formation mechanism of defects was analysed. Research results show that the appropriate laser power and scanning speed resulted in excellent single-melt path formability. When the scanning spacing was 80 μm, adjacent trajectories were closely connected without spheroidised particles and porosity defects. The densest samples were obtained at an energy density of 125 J/mm3with maximum microhardness (86.8 ± 1.5 HV), and the compressive yield strength and ultimate strength reached 301.8 ± 5 MPa and 467.9 ± 5 MPa.

ABSTRACTLong noncoding RNA (lnc RNA) is aberrant expressed in many kinds of tumors and may be concerned with the occurrence and progression of tumors. Lnc RNA MST1P2 is increased in cervical cancer (CC), but its mechanism in CC has not been clarified. In this study, RT-qPCR was employed to analyze Lnc MST1P2 and miR-133b expression. CCK8 and cell apoptosis assay detect the proliferation optical density (OD) value and apoptosis rate. Cell metastasis was evaluated by Wound-healing assay and Transwell assay. Dual-Luciferase assay analyzed the relationship between Lnc MST1P2 and miR-133b. In vivo experiment was performed by establishing xenograft animal model. We found that Lnc MST1P2 is obviously overexpression in CC tissues and cells. Si-Lnc MST1P2 obviously repressed cell growth, cell migration, and cell invasion in Hela and SIHA cells. Moreover, Si-Lnc MST1P2 suppressed CC tumorigenesis in vivo. Dual-Luciferase assay and RT-qPCR assay further proved that Lnc MST1P2 has a negative regulation to miR-133b. miR-133b up-regulation inhibited cell viability and metastasis of Hela and SIHA cells. miR-133b inhibition notably decreased the anti-cancer effect of si-Lnc MST1P2. LncRNA MST1P2 serves as a Cervical Cancer oncogene by sponging with miR-133b.

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Modern sugarcanes are polyploid interspecific hybrids, combining high sugar content from Saccharum officinarumwith hardiness, disease resistance and ratooning of Saccharum spontaneum. Sequencing of a haploid S. spontaneum, AP85-441, facilitated the assembly of 32 pseudo-chromosomes comprising 8 homologous groups of 4 members each, bearing 35,525 genes with alleles defined. The reduction of basic chromosome number from 10 to 8 in S. spontaneumwas caused by fissions of 2 ancestral chromosomes followed by translocations to 4 chromosomes. Surprisingly, 80% of nucleotide binding site-encoding genes associated with disease resistance are located in 4 rearranged chromosomes and 51% of those in rearranged regions. Resequencing of 64 S. spontaneumgenomes identified balancing selection in rearranged regions, maintaining their diversity. Introgressed S. spontaneumchromosomes in modern sugarcanes are randomly distributed in AP85-441 genome, indicating random recombination among homologs in different S. spontaneumaccessions. The allele-defined Saccharumgenome offers new knowledge and resources to accelerate sugarcane improvement.

Let Ybe a random variable such that the moment generating function of Yexists in a neighborhood of the origin. The aim of this paper is to study probabilistic versions of the degenerate Fubini polynomials and the degenerate Fubini polynomials of order r, namely the probabilisitc degenerate Fubini polynomials associated with Yand the probabilistic degenerate Fubini polynomials of order rassociated with Y. We derive some properties, explicit expressions, certain identities and recurrence relations for those polynomials. As special cases of Y, we treat the gamma random variable with parameters α,β>0, the Poisson random variable with parameter α>0, and the Bernoulli random variable with probability of success p.

Effects of chloride ion introduction on structural and 1.5?μm emission properties in Er^3+-doped fluorophosphate have been investigated. The structural changes revealed by the measured Raman spectra indicate that the chloride ions have an important influence on the phonon density of host glasses. With increasing chloride content, the phonon density of fluorophosphate glasses decreases. The chloride modified fluorophosphate glasses possessing higher thermal stability are suitable for broadband amplifier fiber fabrication. Desirable thermal resistance properties and spectroscopic characteristics of Er^3+-doped chloride fluorophosphate glass indicate that it is a promising material for 1.5?μm lasers.

The exact intensity distribution expression for the spatial and temporal Gaussian-shaped femtosecond laser pulse diffracted by a rectangle reflection grating is derived. The spatial and temporal diffraction characteristics are theoretically investigated in detail, and a criterion for judging whether or not the diffraction pulse is just split into two independent pulses in the temporal domain is obtained. The results show that the diffraction intensity in the temporal domain consists of three parts: the intensity diffracted by the upper reflection surface of the grating, the intensity diffracted by the nether reflection surface, and their temporal coherent intensity. The temporal coherent intensity becomes weaker, even is zero, for the higher height from the nether surface to the upper surface of the grating. The principal maximum becomes more sharply bright for the bigger waist width of the femtosecond laser pulse in the spatial domain.

Transition metal phosphides are promising alternatives to the precious metal catalysts for various electrocatalysis applications. Controllable and precise surface engineering of electrocatalysts is the key challenge to enhance their performance. Herein, we demonstrate an ion-exchange strategy to produce cobalt phosphide nanowires which have a conductive core and a thickness-controlled surface layer with sulfur dopants, phosphorus vacancies, and amorphous domains. They are applied for hydrogen evolution reaction with high stability, achieving a current density of 100 mA cm-2at an overpotential of 114 mV. Based on both comprehensive state-of-the-art experimental characterizations and theoretical investigations, the excellent catalytic performance is attributed to increased active sites, facilitated charge transfer and transport, as well as weakened H adsorption and strengthened H2O adsorption due to the synergistic effects of S dopants and P vacancies.

This Letter reports intense emission at 2.7 μm and broadband emission at 2.0 μm from Er^3+/Tm^3+/Ho^3+-doped fluorophosphate glass. The fluorescence characteristics and energy transfer upon excitation of a conventional 980 nm laser diode are investigated. Based on the fluorescence spectra and lifetime measurement, the effect of Tm^3+ and Ho^3+ ions on intense 2.7 μm emission in fluorophosphate glass is demonstrated. It is also found that the effective bandwidth of 2.0 μm emission due to Tm^3+ and Ho^3+ ions can reach as high as 196 nm. These results indicate that the advantageous spectroscopic characteristics of Er^3+/Tm^3+/Ho^3+ triply doped fluorophosphate glass together with the outstanding thermal properties may become an attractive host for the mid-IR solid state lasers.

A novel Er^3+/Pr^3+ codoped germanate glass was fabricated and analyzed. Efficient emission at 2.7?μm from the glass was observed upon excitation of a conventional 980?nm laser diode. The 2.7?μm emission characteristics and energy transfer (ET) were investigated. Population inversions between I_13/24 and I_11/24 levels have been achieved, and an enhanced emission from 2550 to 2800?nm was obtained. Large ET efficiency of 95% indicates that the ET process from Er^3+ to Pr^3+(I4_13/2,H3_4)?(I4_15/2,F3_3) is efficient and that Pr^3+ can enhance the emission of 2.7?μm by quenching the lower laser level of Er^3+ via ET.

This work reports the intense emission at 2.7μm in a Er^3+/Pr^3+-codoped fluorophosphate (FP) host glass. This FP glass shows good thermal stability and high transmittance around 3μm. The emission characteristic and energy transfer upon excitation of a conventional 980nm laser diode are investigated. The prepared glass possesses higher spontaneous transition probability (22.16s^−1) along with a larger calculated emission cross section (6.57±0.11)×10^−21cm^2 corresponding to the laser transition ^4I_11/2?^4I_13/2. In addition, the effect of Pr^3+ codoping on the 2.7μm photoluminescence in FP glass is demonstrated. Hence, the advantageous spectroscopic characteristics of Er^3+/Pr^3+-codoped FP glass together with the outstanding thermal property indicate that this kind of glass may become an attractive host for developing solid-state lasers at around 2.7μm.

In the version of this article originally published, the accession codes listed in the data availability section were incorrect and the section was incomplete. The text for this section should have read “The genome assembly and gene annotation have been deposited in the NCBI database under accession number QVOL00000000, BioProject number PRJNA483885 and BioSample number SAMN09753102. The data can also be downloaded from the following link: http://www.life.illinois.edu/ming/downloads/Spontaneum_genome/.” The errors have been corrected in the HTML and PDF versions of the article.

In [J. Opt. Soc. Am. B28, 1638 (2011)] the wrong version of Fig. 4 was published; a duplicate of Fig. 1 was given. The figure has been corrected online as of September 26, 2011: http://www.opticsinfobase.org/josab/abstract.cfm?URI=josab‐28‐7‐1638.