Screening of phosphorus solubilizing microorganisms in cold environment and their effects on the growth of Brassica napus.

To screen out phosphorus solubilizing strains that can adapt to cold climate in Qinghai Province, Bacillus mucilaginosus, B. megaterium, B. cereus, Streptomyces violovariabilis, S. cinnamofuscus, and S. flavoagglomeratus were screened with solid plate medium as the primary and liquid medium as the secondary screening, with calcium phosphate, lecithin, and phytic acid as the single source of phosphorus. By comprehensively comparing the size of phosphate solubilizing circle in the solid plate medium and the soluble phosphorus content in the liquid medium, three strains of phosphate solubilizing bacteria with good phosphate solubilizing effects were screened, S. violovariabilis, S. cinnamofuscus, and B. mucilaginosus. The three phosphate solubilizing bacteria were made into liquid ino-culants, and the small rapeseed pot experiment was carried out with two soils with different fertilities in a cold climate in September. Compared with the control, plant height, fresh weight, root length, and root weight of rapes in high-fertility cultivated soil increased by 35.5%, 191.0%, 26.2%, and 282.7%, while plant phosphorus absorption, total phosphorus and available phosphorus contents in the rhizosphere soil increased by 968.9%, 5.1%, and 2.1%, respectively. In low-fertility soil, plant height and fresh weight was increased by 45.8% and 61.3%, root length and weight was decreased by 2.6% and 4.4%, while plant phosphorus absorption and the contents of total P and available P in rhizosphere soil were increased by 91.5 %, 29.1%, and 213.7%, respectively. The effect of the other two inoculants treatments was less significant than S. violovariabilis. Therefore, S. violovariabilis was the phosphate solubilizing strain suitable for the cold climate in Qinghai.

Electrochemical Tri- and Difluoromethylation-Triggered Cyclization Accompanied by the Oxidative Cleavage of Indole Derivatives.

Considering their unique roles in organic synthesis, and pharmaceutical and agrochemical applications, the development of fluoroalkylation, cyclization, and indole oxidative cleavage are important topics. Herein, an unprecedented electrochemical tri- and difluoromethylation/cyclization/indole oxidative cleavage process occurring in an undivided cell is presented. The protocol employs a readily prepared Langlois reagent as the fluoroalkyl source, affording a series of tri- or difluoromethylated 2-(2-acetylphenyl)isoquinoline-1,3-diones in good yields with excellent stereoselectivity. It is worth noting that this new methodology merges the fluoroalkylation/cyclization of N-substituted acrylamide alkenes with the oxidative cleavage of an indole C(2)=C(3) bond under external oxidant-free conditions.

Visible-Light Photocatalytic Tri- and Difluoroalkylation Cyclizations: Access to a Series of Indole[2,1-a]isoquinoline Derivatives in Continuous Flow.

A process for achieving photocatalyzed tri- and difluoromethylation/cyclizations for constructing a series of tri- or difluoromethylated indole[2,1-a]isoquinoline derivatives is described. This protocol utilized an inexpensive organic photoredox catalyst and provided good yields. Moreover, the combination of continuous flow and photochemistry, designed to provide researchers with a unique green process, was also shown to be key to allowing the reaction to proceed (product yield of 83% in flow vs 0% in batch).

[The effects of sustained military occupational activities on inhibitory control ability in low temperature environment].

Objective: To evaluate the effects of sustained military occupational activities on inhibitory control ability in low temperature environment, which could provide a basis for accurate military physical training. Methods: Twenty healthy male young cadets (mean age: (23. 32±1. 62)y; height: (175. 34±4. 14)cm; body weight: (68. 19±3. 12)kg) were enrolled in this experiment. A number of military tasks last 36 hours were completed in the ordinary (16℃～23℃) and low(-3℃～-1℃) temperature environment, and the RR interval and core temperature were recorded. The stroop-word-color test and critical frequency test were performed before and after the activities. Results: Compared with rest, the heart rate, excess post-exercise oxygen consumption and training impulse were increased significantly (P＜0. 05) in military occupational activities, however there was no significant difference between the two activities (P＞0. 05). Compared with the rest, the average and maximum core temperature were increased significantly (P＜0. 05), however, compared with the ordinary temperature environment, the average core temperature in the low temperature environment was increased significantly (P＜0. 05), and there was no significant difference in the maximum core temperature (P＞0. 05). Compared with rest, the inhibitory control ability after the two activities was significantly lower (P＜0. 05), which was much worse in the low temperature environment than that in the ordinary temperature environment (P＜0. 05). In addition, compared with rest, both activities led to obvious mental fatigue (P＜0. 05), which was more serious in low temperature environment (P＜0. 05). Conclusion: The sustained military activities can impair the inhibitory control ability, and cause the mental fatigue, in addition, the stress of low temperature can aggravate the negative effects.

Robust digital watermarking for color images in combined DFT and DT-CWT domains.

Image watermarking focuses on hiding secret data into the cover image imperceptibly to protect the copyright of the original image. In this paper, we propose a new framework of robust digital watermarking for color images using combined embedding techniques of Discrete Fourier Transform (DFT) and Dual Tree Complex Wavelet Transform (DTCWT). The cover image is first divided into Y, U and V channels. The Y channel is then transformed by DFT and partitioned into the ring shapes. With an embedding key, we generate pseudo-random patterns to represent the watermark. These patterns are also transformed and partitioned. The watermark represented by the selection of patterns is then embedded into the rings of the DFT coefficients. We further embed a rectification watermark into the U channel, in which DTCWT is applied to achieve a capability of geometric distortion resilience. On the recipient's side, the detection and extraction of watermark can be successfully done. Compared with previous schemes, the proposed method is better on preserving the image quality. Meanwhile, the robustness against typical attacks is also stronger.

Steganography in beautified images.

Existing distortion functions in steganography which achieved high undetectability are designed for unprocessed natural image. Nowadays, a large number of images are filtered before transmitting for the sake of beautification. In this situation, existing distortion functions should be improved to fit the properties of these beautified images. This paper proposes a distortion function optimization method for steganography on beautified images. Given an unprocessed image, a popular image beautification software is employed to produce two similar beautified images. One of them is used for embedding and the other one is employed as reference. Guided by the reference, existing distortion functions are improved by distinguishing the embedding costs for ±1 embedding. After embedding, the stego image is closer to the reference, which results in a higher undetectability against steganalysis. Experimental results also proved the increasing of undetectability when examined by modern steganalytic tools.