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Edge states emerge in diverse areas of science, offering promising opportunities for the development of future electronic or optoelectronic devices, sound and light propagation control in acoustics and photonics. Previous experiments on edge states in photonics were carried out mostly in linear regimes, but the current belief is that nonlinearity introduces more striking features into physics of edge states, leading to the formation of edge solitons, optical isolation, making possible stable lasing in such states, to name a few. Here we report the observation of edge solitons at the zigzag edge of a reconfigurable photonic graphene lattice created via the effect of electromagnetically induced transparency in an atomic vapor cell with controllable nonlinearity. To obtain edge solitons, Raman gain is introduced to compensate strong absorption experienced by the edge state during propagation. Our observations may open the way for future experimental exploration of topological photonics on this nonlinear, reconfigurable platform. Edge states are excitations existing at the boundary of truncated periodic materials with specific spectral degeneracies, and their properties are enriched when materials possess a nonlinear response. Here, the authors provide experimental evidence of edge soliton formation in a nonlinear photonic graphene lattice induced in an atomic vapour cell.

In this paper we address a special case of ‘sloppy’ quantum estimation procedures which happens in the presence of intertwined parameters. A collection of parameters are said to be intertwined when their imprinting on the quantum probe that mediates the estimation procedure, is performed by a set of linearly dependent generators. Under this circumstance the individual values of the parameters can not be recovered unless one tampers with the encoding process itself. An example is presented by studying the estimation of the relative time-delays that accumulate along two parallel optical transmission lines. In this case we show that the parameters can be effectively untwined by inserting a sequence of balanced beam splitters (and eventually adding an extra phase shift on one of the lines) that couples the two lines at regular intervals in a setup that remind us a generalized Hong-Ou-Mandel interferometer. For the case of two time delays we prove that, when the employed probe is the frequency-correlated biphoton state, the untwining occurs in correspondence of exclusive zero-coincidence (EZC) point. Furthermore we show the statistical independence of two time delays and the optimality of the quantum Fisher information at the EZC point. Finally we prove the compatibility of this scheme by checking the weak commutativity condition associated with the symmetric logarithmic derivative operators.

Coherent quantum transduction between microwave and optical signals is of great importance for long-distance quantum communication. Here we propose a novel scheme for the implementation of nonreciprocal single-photon state conversion between microwave and optical modes based on a hybrid magnonic system. A yttrium–iron–garnet (YIG) sphere with both the optomechanical and the optomagnetic properties is exploited to couple with a three-dimensional superconducting microwave resonator. The magnetostatic mode of the YIG sphere is treated as an intermediate to interact with the microwave and optical modes simultaneously. By manipulating the amplitudes and phase differences between the couplings via external driving fields, we show that the nonreciprocal microwave-light single-photon state conversion can be realized via the quantum interference effect.

Diazotrophs play a key role in biological nitrogen (N₂) fixation. However, we know little about the distribution of the diazotrophic community along the soil profile in paddy fields. Here, we used Illumina MiSeq sequencing, targeting the nitrogenase reductase (nifH) gene, to investigate changes with depth (0–100 cm) in the diazotrophic community in paddy soils of three regions (Changshu, Hailun, and Yingtan) in China. The results indicated that most diazotrophs belonged to the phylum Proteobacteria, accounting for 78.05% of the total number of sequences. The diazotrophic diversity was generally highest in the 10–20 cm layer, and then significantly decreased with soil depth. Principal coordinate analysis and PERMANOVA indicated that the diazotrophic community structure was significantly affected by region and soil depth. There were obvious differences in the composition of the diazotrophic community between the topsoil (0–40 cm) and the subsoil (40–100 cm). Anaeromyxobacter, Sideroxydans, Methylomonas, Nostoc, Methanocella, and Methanosaeta were enriched in the topsoil, while Geobacter, Azoarcus, Bradyrhizobium, and Dechloromonas were concentrated in the subsoil. Furthermore, co-occurrence network analysis showed that the diazotrophic network in the topsoil was more complex than that in the subsoil. Distance-based redundancy analysis indicated that soil total C and N content and pH were the main factors influencing the vertical variation in the diazotrophic community. These results highlighted that depth has a great impact on the diazotrophic diversity, community composition, and co-occurrence patterns in paddy soil.

Scenedesmus spp. have been reported as potential microalgal species used for the lipid production. This study investigated the effects of light intensity (at three levels: 50, 250, and 400 μmol photons m −2  s −1 ) on the growth and lipid production of Scenedesmus sp. 11-1 under N-limited condition. Carotenoid to chlorophyll ratio was higher when algae 11-1 grew under 250 and 400 μmol photons m −2  s −1 than that under 50 μmol photons m −2  s −1 , while protein contents was lower. Highest biomass yield (3.88 g L −1 ), lipid content (41.1 %), and neutral lipid content (32.9 %) were achieved when algae 11-1 grew at 400 μmol photons m −2  s −1 . Lipid production was slight lower at 250 μmol photons m −2  s −1 level compared to 400 μmol photons m −2  s −1 . The major fatty acids in the neutral lipid of 11-1 were oleic acid (43–52 %), palmitic acid (24–27 %), and linoleic acid (7–11 %). In addition, polyunsaturated fatty acids had a positive correlation with total lipid production, and monounsaturated fatty acids had a negative one.

Multiple primary cancer (MPC) denotes individuals with two or more malignant tumors occurring simultaneously or successively. Herein, a total of 11,000 pancancer patients in TCGA database (1993–2013) were divided into MPC or non-MPC groups based on their history of other malignant tumors. The incidence of MPC has risen to 8.5–13.1% since 2000. Elderly individuals, males, early-stage cancer patients, and African Americans and Caucasians are identified as independent risk factors (p < 0.0001). Non-MPC patients exhibit significantly longer overall survival (OS) and disease-free survival (DFS) (p = 0.0038 and p = 0.0014). Age (p < 0.001) and tumor staging at initial diagnosis (p < 0.001) contribute to this difference. In our center, MPC was identified in 380 out of 801 tumor events based on SEER criteria. The peak occurrence of secondary primary was about 1–5 years after the first primary tumor, with a second small peak around 10–15 years. Multiple tumors commonly occur in the same organ (e.g., breast and lung), constituting 12.6%. Certain cancer types, notably skin cutaneous melanoma (SKCM), exhibit significantly higher tumor mutational burden (TMB) in the MPC group (17.31 vs. 6.55 mutations/MB, p < 0.001), with high TMB associated with improved survival (p < 0.001). High TMB in MPC may serve as a predictor for potential immunotherapy application.

Understanding the function of essential genes in Clostridium ljungdahlii is critical for unraveling its autotrophic metabolism and optimizing its potential as a platform for syngas fermentation. However, study on essential genes of this species remains insufficient. Here, we employed an inducible CRISPR interference (CRISPRi) system to investigate the roles of key metabolic and cell division genes in C. ljungdahlii. Targeted repression of genes encoding pyruvate:ferredoxin oxidoreductase (PFOR1, PFOR2), acetaldehyde:ferredoxin oxidoreductase (AOR1, AOR2), and glyceraldehyde phosphate hydrogenase type I (GAP-I) revealed their essential contributions to autotrophic growth, as knockdown strains exhibited impaired growth and reduced ethanol production. Furthermore, downregulation of the cell division gene ftsZ resulted in elongated cell morphology, highlighting its critical role in cell shape regulation. These findings provide new insights into the functional importance of essential genes in C. ljungdahlii and demonstrate how targeted gene repression can advance our understanding of autotrophic metabolism and cellular processes.

A novel bacterium, Cr-10, was isolated from a chromium-contaminated site and capable of removing toxic chromium species from solution by reducing hexavalent chromium to an insoluble precipitate. Sequence analysis of 16S rRNA gene of strain Cr-10 showed that it was most closely related to Serratia rubidaea JCM 1240^sup T^ (97.68%). Physiological and chemotaxonomic data also supported that strain Cr-10 was identified as Serratia sp., a genus which was never specially reported chromate-resistant before. Serratia sp., Cr-10 was tolerant to a concentration of 1,500 mg Cr(VI) L^sup -1^, which was the highest level reported until now. The optimum pH and temperature for reduction of Cr(VI) by Serratia sp. Cr-10 were found to be 7.0 and 37 °C, respectively. The Cr(VI) reduction was significantly influenced by additional carbon sources, and among them fructose and lactose offered maximum reduction, with a rate of 0.28 and 0.25 mg Cr(VI) L^sup -1^ h^sup -1^, respectively. The cell-free extracts and filtrate of the culture were able to reduce Cr(VI) while concentration of total chromium remained stable in the process, indicating that the enzyme-catalyzed mechanism was applied in Cr(VI) reduction by the isolate. Additionally, it was found that there was hardly any chromium on the cell surface of the strain, further supporting that reduction, rather than bioadsorption, plays a major role in the Cr(VI) removal.[PUBLICATION ABSTRACT]

Wheat bran, a by-product of the wheat milling industry, consists mainly of hemicellulose, starch and protein. In this study, the hydrolysate of wheat bran pretreated with dilute sulfuric acid was used as a substrate to produce ABE (acetone, butanol and ethanol) using Clostridium beijerinckii ATCC 55025. The wheat bran hydrolysate contained 53.1 g/l total reducing sugars, including 21.3 g/l of glucose, 17.4 g/l of xylose and 10.6 g/l of arabinose. C. beijerinckii ATCC 55025 can utilize hexose and pentose simultaneously in the hydrolysate to produce ABE. After 72 h of fermentation, the total ABE in the system was 11.8 g/l, of which acetone, butanol and ethanol were 2.2, 8.8 and 0.8 g/l, respectively. The fermentation resulted in an ABE yield of 0.32 and productivity of 0.16 g l⁻¹ h⁻¹. This study suggests that wheat bran can be a potential renewable resource for ABE fermentation.

The interaction between vector beams and atoms under a weak magnetic field could induce spatially dependent electromagnetically induced transparency (EIT). Based on such a coherence effect, we propose a method for manipulating vector beams carrying spiral varying phases in hot rubidium atoms. When a transverse magnetic field (TMF) is applied, the transparent regions of the transmitted beam are strongly depend on the beam’s polarization distribution. In addition to the intensity modulation, the alignment of the TMF is reflected in the rotation of the central symmetric transmission patterns. In theory, we discuss the physical mechanism of the spiral EIT region generated by the phase profile, and analyze the influence of system parameters on this coherent process. Our work confirms that introducing additional radial phases can also lead to spatially dependent EIT, which extends another degree of freedom to manipulate atomic polarization. This will provide potential applications in light field manipulation and multi-dimensional quantum storage.