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Fourteen Gram-stain-positive bacterial strains were isolated from Chinese traditional pickle and yogurt. The strains were characterized using a polyphasic taxonomic approach, including 16S rRNA gene sequence analysis, pheS gene sequence analysis, rpoA gene sequence analysis, fatty acid methyl ester analysis, determination of DNA G+C content, determination of average nucleotide identity (ANI), in silico DNA–DNA hybridization (isDDH) and an analysis of phenotypic features. The data demonstrated that the 14 strains represented ten novel species belonging to the genus Lactobacillus , strains 73-4T, 247-3T, 143-4(a)T, 33-1T, 143-6T, 247-4T, 17-4T, 143-1T, 735-2T and M1530-1T were designated as the type strains. Strains 73-4T and 247-3T were phylogenetically related to the type strains of Lactobacillus camelliae and Lactobacillus jixianensis , having 97.0–98.9 % 16S rRNA gene sequence similarities, 83.9–87.2 % pheS gene sequence similarities and 86.8–93.3 % rpoA gene sequence similarities. Strains 143-4(a)T and 33-1T were phylogenetically related to the type strains of Lactobacillus rhamnosus , Lactobacillus paracasei and Lactobacillus casei , having 93.6–96.5 % 16S rRNA gene sequence similarities, 73.9–77.2 % pheS gene sequence similarities and 76.1–77.6 % rpoA gene sequence similarities. Strains 143-6T, 247-4T, 17-4T and 143-1T were phylogenetically related to the type strains of Lactobacillus concavus , Lactobacillus dextrinicus and Lactobacillus bayanensis , exhibiting 95.5–99.9 % 16S rRNA gene sequence similarities, 76.5–83.1 % pheS gene sequence similarities and 83.6–98.3 % rpoA gene sequence similarities. Strain 735-2T was phylogenetically related to the type strains of Lactobacillus zhaoyuanensis , Lactobacillus jiayinensis and Lactobacillus coryniformis , having 98.2–99.1 % 16S rRNA gene sequence similarities, 82.8–84.1 % pheS gene sequence similarities and 93.0–93.9 % rpoA gene sequence similarities. Strain M1530-1T was phylogenetically related to the type strains of Lactobacillus suantsaiihabitans and Lactobacillus brevis , having 99.5 and 99.0 % 16S rRNA gene sequence similarities, 90.3 and 81.7 % pheS gene sequence similarities and 97.7 and 91.1 % rpoA gene sequence similarities. The ANI and isDDH values between strains 73-4T, 247-3T, 143-4(a)T, 33-1T, 143-6T, 247-4T, 17-4T, 143-1T, 735-2T, M1530-1T and type strains of phylogenetically related species were less than 86.8 % and 33.9 % respectively, confirming that they represent ten novel species within the genus Lactobacillus . Based upon the data of polyphasic characterization obtained in the present study, ten novel species, Lactobacillus hegangensis sp. nov., Lactobacillus suibinensis sp. nov., Lactobacillus daqingensis sp. nov., Lactobacillus yichunensis sp. nov., Lactobacillus mulanensis sp. nov., Lactobacillus achengensis sp. nov., Lactobacillus wuchangensis sp. nov., Lactobacillus gannanensis sp. nov., Lactobacillus binensis sp. nov. and Lactobacillus angrenensis sp. nov., are proposed and the type strains are 73-4T (=NCIMB 15177T=CCM 8912T=CCTCC AB 2018407T), 247-3T (=NCIMB 15176T=JCM 33275T), 143-4(a)T (=NCIMB 15173T=CCM 8948T=JCM 33273T=CCTCC AB 2018390T), 33-1T (=NCIMB 15169T=CCM 8947T=JCM 33272T=CCTCC AB 2018405T), 143-6T (=NCIMB 15162T=CCM 8951T=JCM 33274T=CCTCC AB 2018411T), 247-4T (=NCIMB 15155T=CCM 8897T=LMG 31059T=CCTCC AB 2018410T), 17-4T (=NCIMB 15161T=CCM 8946T=JCM 33271T=CCTCC AB 2018406T), 143-1T (=NCIMB 15157T=CCM 8937T=CCTCC AB 2018409T), 735-2T (=NCIMB 15190T=CCM 8925T=LMG 31186T) and M1530-1T (=NCIMB 15150T=CCM 8893T=LMG 31046T=CCTCC AB 2018402T), respectively.

A relatively rigid acyclic salamo-type ligand H2L and its square planar Cu(II) complex, [Cu(L)]·CH3OH, were synthesized and characterized by X-ray crystallography, as well as Fourier-transform infrared spectra, UV–Vis spectra, Hirshfeld surface analyses and DFT calculations. The ligand crystallizes in monoclinic space group P 21/c and has pairs of intramolecular hydrogen bonds between the oxime nitrogen atoms and the hydroxyl groups. The Cu(II) complex crystallizes in the monoclinic space group P 21/c. The Cu(II) ion is located in the N2O2 cavity of the fully deprotonated salamo-type ligand (L)2− unit, thus forming a four-coordinate distorted square planar geometry. At the same time, a belt-like, 2-D supramolecular structure is formed by the interaction of intermolecular hydrogen bonds, and the intermolecular interaction force is quantitatively analyzed by Hirshfeld surfaces. Significantly, fluorescence properties of the ligand and its Cu(II) complex were also studied. The coordination ratio of the Cu(II) complex was proved by UV–Vis and fluorescence titration experiments.

The ever-increasing trend of greenhouse gas (GHGs) emissions is accelerating global warming and threatening food security. Environmental benefits and sustainable food production must be pursued locally and globally. Thus, a field experiment was conducted in 2015 to understand how to balance the trade-offs between agronomic productivity and environment quality in the North China Plain (NCP). Eight treatments consisted of two factors, i.e., (i) tillage practices: rotary tillage (RT) and no-till (NT), and (ii) cropping sequences (CS): maize-wheat-soybean-wheat (MWSW), soybean-wheat-maize-wheat (SWMW), soybean-wheat (SW), and maize-wheat (MW). The economic and environmental benefits were evaluated by multiple indicators including the carbon footprint (CF), maize equivalent economic yield (MEEY), energy yield (EY), carbon sustainability index (CSI), etc. Compared with NT, RT increased the EY and MEEY, but emitted 9.4% higher GHGs. Among different CSs, no significant reduction was observed in CF. The lowest (2.0 Mg CO2-eq ha-1 yr-1) and the highest (5.6 Mg CO2-eq ha-1 yr-1) CF values were observed under MW and SWMW, respectively. However, CSs with soybean enhanced MEEY and the net revenue due to its higher price compared to that of MW. Although the highest CSI was observed under RT-MW, soybean-based crop rotation could offset the decline in CSI under NT when compared to that for RT. These findings suggest that conservation agriculture (CA) could enhance the balance in trade-offs between economic and environmental benefits. Additional research is needed on how to achieve high crop production by establishing a highly efficient conservation agriculture system in the NCP.

Conservation agriculture (CA) has been adopted worldwide on about 200 Mha to enhance soil organic carbon (SOC) for mitigating climate change. However, as a crucial mechanism to sequester SOC, how the protection of aggregates responds to the interaction between no-till and crop rotations (two principles of CA) remains unknown. Thus, a field experiment with six treatments [e.g., no-till or rotary tillage under the maize-wheat-soybean-wheat system (NT-MWSW, RT-MWSW), no-till or rotary tillage under the maize-wheat system (NT-MW, RT-MW), and no-till or rotary tillage under the soybean-wheat system (NT-SW, RT-SW)] was conducted from June 2018 to June 2021 in the North China Plain (NCP) to assess their effects on aggregation and SOC. Results indicated that macroaggregates (0.25 mm) were the main contributors to the soil carbon (C) pool, comprised 64.7-87.3 % of aggregates, and encompassed 64.9-73.1 % of the SOC stock. NT increased not only the proportion of macroaggregates but also aggregate stability (i.e., mean weight diameter and geometric mean diameter). Significant positive effects from legumes were observed under NT. SW increased by 13.6 % macroaggregate-associated SOC under NT in 0-20 cm compared to that under MW. Additionally, the conversion rate of straw C input under NT-SW was higher than that in other treatments, augmenting it by 9.4-21.9 %. This may be attributed to the higher macroaggregate total nitrogen (increased by 1.7-15.9 %) in 0-10 cm under legume-based crop rotations compared to that under MW, resulting in lower C: N ratios, which promoted the decomposition of straw. Furthermore, the total potential mineralization of macroaggregates under NT legume-based crop rotations was 3.0-16.0 % higher than that of MW. Thus, a legume-based NT system can significantly improve soil macro-aggregation, increase the conversion rate of straw C input, and reduce C loss, which can be a viable practice to enhance SOC sequestration capacity under CA in the NCP.

Fourteen Gram-stain-positive bacterial strains were isolated from Chinese traditional pickle and yogurt. The strains were characterised using a polyphasic taxonomic approach, including 16S rRNA gene sequence analysis, pheS gene sequence analysis, rpoA gene sequence analysis, determination of DNA G+C content, determination of average nucleotide identity, fatty acid methyl ester analysis and an analysis of phenotypic features. The data demonstrated that the fourteen strains represented nine novel species belonging to the genus Lactobacillus , strains 54-2T, 54-5T, 33-7T, 116-2T, 184-8T, 204-8T, 8-1(1)T, 256-3T and M1575T were designated as the type strains. Strain 54-2T was phylogenetically related to the type strains of Lactobacillus composti and Lactobacillus floricola , having 96.5 and 91.6 % 16S rRNA gene sequence similarities, less than 74.6 % pheS gene sequence similarities, less than 81.6 % rpoA gene sequence similarities and less than 72.5 % ANI values. Strain 54-5T was phylogenetically related to the type strains of Lactobacillus dextrinicus and Lactobacillus concavus , exhibiting 99.1 and 97.3 % 16S rRNA gene sequence similarities, less than 83.1 % pheS gene sequence similarities, less than 93.1 % rpoA gene sequence similarities and less than 79.9 % ANI values. Strains 33-7T, 116-2T, 184-8T, 204-8T, 8-1(1)T, 256-3T and M1575T were phylogenetically related to the type strains of Lactobacillus tucceti , Lactobacillus nodensis , Lactobacillus insicii , Lactobacillus allii , Lactobacillus metriopterae , Lactobacillus terrae , Lactobacillus versmoldensis and Lactobacillus furfuricola , sharing 95.6–100 % 16S rRNA gene sequence similarities, less than 91.6 % pheS gene sequence similarities, less than 98.2 % rpoA gene sequence similarities and less than 89.4 % ANI values. Based upon the data of polyphasic characterisation obtained in the present study, nine novel species, Lactobacillus yilanensis sp. nov., Lactobacillus bayanensis sp. nov., Lactobacillus keshanensis sp. nov., Lactobacillus kedongensis sp. nov., Lactobacillus baiquanensis sp. nov., Lactobacillus jidongensis sp. nov., Lactobacillus hulinensis sp. nov., Lactobacillus mishanensis sp. nov. and Lactobacillus zhongbaensis sp. nov., are proposed and the type strains are 54-2T (=NCIMB 15154T=CCM 8896T=KCTC 21120T=LMG 31058T), 54-5T (=NCIMB 15151T=CCM 8894T), 33-7T (=NCIMB 15153T=CCM 8936T=KCTC 21118T=LMG 31166T), 116-2T (=NCIMB 15158T=CCM 8899T=KCTC 21124T=LMG 31051T), 184-8T (=NCIMB 15152T=CCM 8895T=KCTC 21131T=LMG 31050T), 204-8T (=NCIMB 15159T=CCM 8900T=KCTC 21133T=LMG 31054T), 8-1(1)T (=NCIMB 15156T=CCM 8898T=KCTC 21115T=LMG 31047T), 256-3T (=NCIMB 15160T=CCM 8901T=LMG 31048T) and M1575T (=NCIMB 15149T=CCM 8892T=LMG 31045T), respectively.

Three trinuclear complexes, [{CoL(MeOH)(μ-OAc)}2Co] (1), [{CoL(EtOH)(μ-OAc)}2Co]·2CH3CH2OH (2) and [{NiL(MeOH)(μ-OAc)}2Ni]·2CH3OH (3) have been successfully synthesized by wet-chemical method using asymmetric salamo-based polydentate chelating ligand (H2L) with transition metal(II) acetate (Co(OAc)2·4H2O or Ni(OAc)2·4H2O). The ligand H2L with N2O2 coordination cavity can accommodate transition metals, at the same time, the oxygen atoms of the phenolic hydroxyl groups can bridge the metal atoms to obtain muiltnuclear metal complexes. There are inversion centers in complexes 1–3 and all M(II) atoms possess six-coordinated distorted octahedral geometries. Complexes 1 and 3 are further assembled into extended two-dimensional supramolecular via intermolecular interactions, but complex 2 forms three-dimensional supramolecular structure. The interactions were quantitatively determined by Hirshfeld surfaces analyses. Significantly, complexes 1–3 have been characterized by elemental analyses, IR spectra, UV–Vis spectroscopy and X-ray crystallography analyses. Fluorescence properties were also investigated.

A phenomenon of modal instability is investigated theoretically in some high power solid-state lasers with an unstable cavity. This modal instability is caused by a thermo-optic-thermo feedback coupled with an asymmetrical laser oscillation inside some unstable cavities. Numerical investigations indicate that this instability can appear in all lasers with Nd3+-doped disk scheme, Yb3+-doped disk scheme and direct-liquid-cooled slab scheme, but the physical mechanisms of optic-thermo feedback in the three schemes are completely different. It is shown that the modal instability can appear within a special power range only in the Nd- or Yb-doped disk lasers due to certain saturation phenomenon, but exhibits a power threshold in the direct-liquid-cooled slab lasers. Therefore different strategies to mitigate the modal instability in different lasers are suggested. Finally, the presence of transverse modal instability in the Nd:YAG thin-disk laser is confirmed qualitatively by an experiment.

To improve the classification accuracy and reduce the training time, an intrusion detection technology is proposed, which combines feature extraction technology and multiclass support vector machine (SVM) classification algorithm. The intrusion detection model setup has two phases. The first phase is to project the original training data into kernel fisher discriminant analysis (KFDA) space. The second phase is to use fuzzy clustering technology to cluster the projected data and construct the decision tree, based on the clustering results. The overall detection model is set up based on the decision tree. Results of the experiment using knowledge discovery and data mining (KDD) from 99 datasets demonstrate that the proposed technology can be an an effective way for intrusion detection.

A eigenmode expansion method (EME) is proposed to solve the laser eigenmode of optical resonator with intra-cavity phase aberration (ICPA) semi-analytically. In this model, the eigen-equation of OR, so called self-reappearance condition is translated to be a linear eigen-value problem, and it is proved that all eigen-modes can be obtained for any resonators. The linear eigen-value problem is solved numerically, and it gives out the transverse distribution and corresponding eigen-value of each eigenmode, which describe the light field and diffraction loss, respectively. Compared with traditional methods, EME is a semi-analytical method which is unlimited by the order of phase aberration, and it can be solved without numerical iteration. The existing of local modes (LM) in OR with ICPA is proved with EME, which may be the source of local damage on solid medium. And the use of output coupler with transmission, such as graded reflectivity mirror (GRM), can prevent the appearance of LM and improve beam quality. Specially, for the ICPA coupled with laser extraction, the linear eigen-value equations become a nonlinear problem, which are numerically solved by the finite-difference Jacobian method. The result shows that the optical resonator exhibits transverse modal instability (TMI) with certain cavity parameters.

In this paper, the operation properties of unstable resonators with graded reflectivity mirror (GRM-UR) are studied numerically in a solid-state thin-disk laser in terms of beam quality and power threshold. By comparing to traditional unstable resonator with same output coupling fraction, results show that the GRM-UR is advantageous to suppress ASE effect, but hard to achieve better beam quality when the phase aberrations cannot be well compensated within the cavity.

In this paper, we propose a new intrusion detection technology which combines feature extraction with wavelet clustering method. Our intrusion detection model setup has two phases, where the first phase is to project the input data into high dimensional space by using the discriminant vectors extracted by Kernel Fisher Discriminant Analysis. By using KFDA, we can reduce the dimension of the input data and make the dataset more separable. Then the second phase is to set up the detection model based on wavelet clustering. We extend original wavelet clustering algorithm for intrusion detection. Second transformation of feature space is processed by using wavelet transform for removing the outliers and making the boundary between clusters clear. Clusters are set up on the second transformed feature space and we label the clusters by using the similarity information between training datasets and clusters. Experiments using the KDD CUP99 dataset demonstrate that by combining KFDA and wavelet clustering can be an effective way for intrusion detection.

A semi-analytical calculation framework is proposed to calculate the eigenmodes of a general laser resonator with arbitrary intra-cavity wavefront aberrations. By solving a linear eigenvalue equation in the complex space, the mode intensity distributions of the eigenmodes in high power unstable resonators are obtained, indicating that due to the aberrations the area of fundamental mode significantly shrinks to form the localized mode with extremely high power intensity. The beam quality, mode area, threshold gain, and operation reliability are compared between the traditional unstable resonator and the one with a graded reflectivity mirror. The simulation results disclose that with a graded reflectivity mirror more high-order modes participate in mode competition and the localized mode effect of fundamental mode is weakened.