Antimony oxidation and whole genome sequencing of Phytobacter sp. X4 isolated from contaminated soil near a flotation site.

The conversion of the more toxic Sb(III) into less toxic Sb(V) is an effective strategy for the treatment of antimony-contaminated sites. In this study, a strain, Phytobacter sp. X4, which can tolerate high concentrations of antimony and can use nitrate as an electron acceptor for Sb(III) oxidation under anaerobic conditions, was isolated from the deep soil of an antimony mine flotation tailing. Unlike other antimony oxidizing bacteria, X4 oxidized better under high Sb(III) concentration, and the oxidation efficiency of 10 mM Sb(III) reached the maximum at 110 h with 61.8 %. Kinetic study showed X4 yielded a Vmax of 1.093 µM∙min-1 and a Km of 718.2 µM. The genome of Phytobacter sp. X4 consists of a complete circular chromosome and two plasmids. In addition, X4 had more metal(loid)s resistance genes and highly expressed genes than other Phytobacter spp., reflecting its stronger adaptive advantage in harsh survival environments. We also analyzed the origin and evolution of arsB, arsC, and arsH, which may have been transferred horizontally from other species. iscR and arsH may have an important contribution to Sb(III) oxidation. Thus, Phytobacter sp. X4 has a good ability to remediate high antimony-contaminated sites and can be applied to an anaerobic environment.

Microbial community structures and their driving factors in a typical gathering area of antimony mining and smelting in South China.

This study investigated soil microbial community in a typical gathering area of antimony mining and smelting in South China. The physical and chemical properties of different soils (mining waste dumps, flotation tailings, and smelting slag) and depths (0-20 cm, 40-60 cm, and 80-100 cm) were compared. The results showed that antimony (Sb) and arsenic (As) were the main pollutants, and their concentrations were 5524.7 mg/kg and 3433.7 mg/kg, respectively. Xanthates were found in the flotation tailings and smelting slag, and the highest concentration was 585.1 mg/kg. The microbial communities were analyzed by high-throughput sequencing, and it was shown that Proteobacteria, Acidobacteria, Chlorobacterium, Bacteroides, and Actinomycetes were the dominant taxa at the phylum level. There were obvious differences in microbial community structure in different sites. The dominant microorganism in the mining site was Chujaibacter. Subgroup_2_unclassified and Gemmatimonadaceae_unclassified were the prevalent microorganisms in the flotation and smelting sites, respectively. As, Sb, and xanthates were the main factors affecting the diversity and composition of bacteria in the flotation tailings and smelting slag areas. Therefore, this study provides experimental guidance and a theoretical basis for soil antimony pollution quality assessment, biological treatment, and environmental remediation.

Push for Center Learning via Orthogonalization and Subspace Masking for Person Re-Identification.

Person re-identification aims to identify whether pairs of images belong to the same person or not. This problem is challenging due to large differences in camera views, lighting and background. One of the mainstream in learning CNN features is to design loss functions which reinforce both the class separation and intra-class compactness. In this paper, we propose a novel Orthogonal Center Learning method with Subspace Masking for person re-identification. We make the following contributions: 1) we develop a center learning module to learn the class centers by simultaneously reducing the intra-class differences and inter-class correlations by orthogonalization; 2) we introduce a subspace masking mechanism to enhance the generalization of the learned class centers; and 3) we propose to integrate the average pooling and max pooling in a regularizing manner that fully exploits their powers. Extensive experiments show that our proposed method consistently outperforms the state-of-the-art methods on large-scale ReID datasets including Market-1501, DukeMTMC-ReID, CUHK03 and MSMT17.

Bullet signature measurement with chromatic confocal sensor.

A new, non-contact, three-dimensional (3D) bullet signature measuring system based on a chromatic confocal sensor is developed. The system is composed of a precision rotary table and a chromatic confocal sensor. The measurement uncertainty of the system is less than 1 µm. When measuring the surface topography of the object, the sensor acquires wavelength information reflected from the object instead of intensity information. This advantage is very suitable to bullet signature measurements. The chromatic confocal sensor works in the point measuring mode and can acquire data continuously with high speed. One round section measurement on the bullet body takes less than 1 minute.

Atypical anterior persistent hyperplastic primary vitreous: report of a rare case.

BACKGROUND: Persistent hyperplastic primary vitreous (PHPV) is a congenital form of vitreous dysplasia that can be categorized into anterior, posterior, and mixed types according to the affected location within the eye. Definitive diagnoses of PHPV are usually made based on B-mode ultrasound, optical coherence tomography (OCT), and Doppler ultrasound findings. In this report, we discuss the case of a 7-year-old boy in whom a definitive diagnosis of atypical anterior PHPV was possible based on intraoperative observations, pathological findings, and the results of ophthalmic examination. CASE PRESENTATION: A 7-year-old boy presented with leukocoria and acute glaucoma in his right eye. Imaging suggested characteristics of mixed PHPV. Surgical treatment and pathological examination were performed due to the presence of acute glaucoma and abnormal lens morphology. Typical signs of posterior PHPV (e.g., eyeball shrinkage, the presence of vascular membranes connected to the optic disc, etc.) were not observed. However, there were abundant fibrous vascular membranes around the lens. Pathological examination revealed fibrocyte proliferation in the lens and capsular tissue. Intraoperative findings were used in conjunction with the results of pathological and ophthalmological examinations to make the final diagnosis of anterior PHPV. CONCLUSION: The course and characteristics of PHPV can be unpredictable, and it is often the case that a clear diagnosis cannot be obtained based on clinical characteristics and typical imaging examinations alone. Further surgical treatment and pathological examination may aid in establishing a final diagnosis. In addition to treating the complications of PHPV (e.g., glaucoma), surgery may improve eye appearance and restore visual function to some degree.

[Change of alpha-crystallin acting as molecular chaperone activity with ageing].

PURPOSE: To evaluate the molecular chaperone function of alpha-crystallin with ageing. METHODS: alpha-Crystallin of newborn, adult and old rabbits lenses in both of cortex and nucleus were separated by chromatography on Sephacryl S-300HR. The protection of alpha-crystallin against thermal aggregation of catalase and beta L-crystallin (60 degrees C), inactivation of catalase by fructose(37 degrees C) and heat stress(60 degrees C) were measured spectrophotometrically. RESULTS: Protection of alpha-crystallin against aggregation and inactivation using four methods showed a similar pattern. The protective ability in cortex was greatly higher than in nucleus of different-aged lenses, and alpha H-crystallin was less than alpha L-crystallin in both cortex and nucleus. There was no statistically decrease with age of chaperone function of both alpha H-crystallin and alpha L-crystallin in the cortex, whereas alpha L-crystallin in the nucleus was compromised. CONCLUSION: alpha-Crystallin in the nucleus shows age-related decrease in chaperone function, which may be responsible for cataract formation.