Peroxydisulfate activation and versatility of defective Fe3O4@MOF-808 for enhanced carbon and phosphorus recovery from sludge anaerobic fermentation.

Although being viewed as a promising technology for reclamation of carbon and phosphorus from excess sludge, anaerobic fermentation (AF) grapples with issues such as a low yield of volatile fatty acids (VFAs) and high phosphorus recovery costs. In this study, we synthesized Fe3O4@MOF-808 (FeM) with abundant defects and employed it to simultaneously enhance VFAs and phosphorus recovery during sludge anaerobic fermentation. Through pre-oxidization of sludge catalyzed by FeM-induced peroxydisulfate, the soluble organic matter increased by 2.54 times, thus providing ample substrate for VFAs production. Subsequent AF revealed a remarkable 732.73 % increase in VFAs and a 1592.95 % increase in phosphate. Factors contributing to the high VFAs yield include the non-biological catalysis of unsaturated Zr active sites in defective FeM, enhancing protein hydrolysis, and the inhibition of methanogenesis due to electron competition arising from the transformation between Fe(III) and Fe(II) under Zr influence. Remarkably, FeM exhibited an adsorption capacity of up to 92.64 % for dissolved phosphate through ligand exchange and electrostatic attractions. Furthermore, FeM demonstrated magnetic separation capability from the fermentation broth, coupled with excellent stability and reusability in both catalysis and adsorption processes.

Diagnostic validation and development of an algorithm for identification of intussusception in children using electronic health records of Ningbo city in China.

BACKGROUND: Monitoring the risk of intussusception after the introduction of rotavirus vaccines is recommended by the World Health Organization (WHO). Although the validity of intussusception monitoring using electronic health records (EHRs) has been confirmed previously, no similar studies have been conducted in China. We aimed to verify the diagnosis and determine an algorithm with the best performance for identification of intussusception using Chinese EHR databases. RESEARCH DESIGN AND METHODS: Using the Regional Health Information Platform in Ningbo, patients aged 0-72 months from 2015 to 2021 with any related visits for intussusception were included. The algorithms were based on diagnostic codes or keywords in different clinical scenarios, and their performance was evaluated with positive predictive value (PPV) and sensitivity in line with the Brighton guidelines. RESULTS: Brighton level 1 intussusception was confirmed in 2958 patients with 3246 episodes. Fine-tuned algorithms combining the appearance of the relevant ICD-10 codes or the Chinese keyword 'Chang Tao' in any diagnostic reports with the results of enema treatments or related surgeries showed the highest sensitivity, while the highest PPV was obtained by further criteria based on typical radiographic appearances. CONCLUSION: Intussusception could be identified and validated internally using EHRs in Ningbo.

Topographic constraints on the distribution of selenium in the supergene environment: A case study at Yutangba, China.

The local topography and leaching conditions significantly affect the spatial distribution of selenium (Se) in the local environment. However, the driving factors controlling Se distribution have not been well addressed. In this paper, taking Yutangba, a village known for human selenosis in China, as an example, we demonstrate how topographic factors influence the spatial distribution of Se in soils and plants. In the scenarios of slope ≤25°, the correlations among slope and soil/extractable/plant Se are significantly negative (P < 0.05), whereas they become weak or unclear when the slope is > 25°, suggesting that 25° of slope is a critical transition boundary. Similar observations were further verified by the soil erosion modulus (SEM) and the surface runoff intensity index (SRI), indicating that Se transport via soil erosion is limited and accounts for 11.2-17% of the soil Se, while surface runoff plays a dominant role in the Se distribution, accounting for 83-88.1%. Soil extractable Se is negatively correlated with SRI (Pearson r = -0.87 at slope < 25°), showing that the migration capacity of Se is higher at steep terrain and controlled by topography through soil erosion and surface runoff. The positive relationship between plant Se and soil/extractable Se demonstrates that topography indirectly influences plant Se through soil Se bioavailability. Abnormally local Se enrichment observed at the elevated steep hillside (>25°) in northwestern Yutangba primarily was resulted from the weathering of Se-rich rocks. These observations confirm that the topographic slope gradient influences the transport and spatial distribution of soil Se, implying that topography should be considered when studying the spatial distribution of soil Se at a regional scale, especially for the Se-poor belt in China.

Microscale Investigation into Selenium Distribution and Speciation in Se-Rich Soils from Enshi, China.

In this study, we investigated the distribution and chemical speciation of Se in Se-rich soil by using micro-focused X-ray absorption near-edge structure (µ-XANES) spectroscopy coupling with X-ray fluorescence (µ-XRF) mapping. The microscale distribution showed that Se is heterogeneously distributed in the soil from seleniferous areas in Enshi, China. Se K-edge µ-XANES analysis suggested that Se is mainly present as Se(IV), organic Se(-II) or Se(0) species in Se-rich agricultural soil. The findings from this study would help improve the understanding of the fate, mobility, bioavailability, and biogeochemical cycling of Se in the seleniferous soil environment.

Temporal heterogeneity of microbial communities and metabolic activities during a natural algal bloom.

Elucidating the interactions between algae and associated microbial communities is critical for understanding the mechanisms that mediate the dynamic of harmful algal blooms (HABs) in marine environment. However, the microbial functional profiles and their biogeochemical potential in HABs process remains elusive, especially during a complete natural HAB cycle. Here, we used pyrosequencing and functional gene array (GeoChip) to investigate microbial community dynamics and metabolic potential during a natural dinoflagellate (Noctiluca scintillans) bloom. The results shown that bacterioplankton exhibited significant temporal heterogeneity over the course of the bloom stages. Microbial succession was co-driven by environmental parameters and biotic interactions. The functional analysis revealed significant variations in microbial metabolism during matter cycling. At bloom onset-stage, metabolic potential associated with iron oxidation and transport was elevated. Carbon fixation and degradation, denitrification, phosphorus acquisition, and sulfur transfer/oxidation were significantly enhanced at the plateau stage. During the decline and terminal stages, oxidative stress, lysis of compounds, and toxin degradation & protease synthesis increased. This work reveal phycosphere microorganisms can enhanced organic C decomposition capacity, altered N assimilation rate and S/P turnover efficiency, and balancing of the Fe budget during HAB process. The ecological linkage analysis has further shown that microbial composition and functional potential were significantly linked to algal blooms occurrence. It suggest that structural variability and functional plasticity of microbial communities influence HAB trajectory.

Functional profiles of phycospheric microorganisms during a marine dinoflagellate bloom.

Harmful algal blooms (HABs) are an ecological concern but relatively few studies have investigated the functional potential of bacterioplankton over a complete algal bloom cycle, which is critical for determining their contribution to the fate of algal blooms. To address this point, we carried out a time-series metagenomic analysis of the functional features of microbial communities at three different Gymnodinium catenatum bloom stages (pre-, peak-, and post-bloom). Different microbial composition were observed during the blooming stages. The environmental parameters and correlation networks co-contribute to microbial variability, and the former explained 38.4% of total variations of the bacterioplankton community composition. Functionally, a range of pathways involved in carbon, nitrogen, phosphorus and sulfur cycling were significantly different during the various HAB stages. Genes associated with carbohydrate-active enzymes, denitrification, and iron oxidation were enriched at the pre-bloom stage; genes involved in reductive citrate cycle for carbon fixation, carbon degradation, nitrification and phosphate transport were enhanced at the peak stage; and relative gene abundance related to sulfur oxidation, vitamin synthesis, and iron transport and storage was increased at the post-bloom stage. The ecological linkage analysis has shown that microbial functional potential especially the C/P/Fe metabolism were significantly linked to the fate of the algal blooms. Taken together, our results demonstrated that microorganisms displayed successional patterns not only at the community level, but also in the metabolic potential on HAB's progression. This work contributes to a growing understanding of microbial structural elasticity and functional plasticity and shed light on the potential mechanisms of microbial-mediated HAB trajectory.

Investigation of Virulence Genes and Resistance Genes in a Group of Staphylococcus aureus Isolated in Yuhang, China.

BACKGROUND: To investigate the distribution of virulence genes and resistance genes in a group of Staphylococcus aureus (S. aureus). METHODS: From February 2013 to April 2014, a total of 39 strains of S. aureus were collected at Hangzhou Yuhang Hospital of Traditional Chinese Medicine, China. Drug sensitivity to 16 kinds of antimicrobial agents was performed by E-test method. A total of 94 virulence genes and 11 resistance genes, including qacA and bsa, were examined by PCR. All virulence and resistance genes were used as molecular markers to perform sample cluster analysis (UPGMA). RESULTS: At least one gene in every class of virulence genes were positive in strains of S. aureus: adherence, exoenzyme, host immune evasion, and toxin. Eleven virulence genes encoding adherence were positive: clfA, clfB, ebpS, fnbA, icaA, isdA, isdB, isdC, sdrC, sdrD, sdrE; 5 virulence genes encoding exoenzyme were positive: hysA, lip, splB, edinB, nuc; 2 virulence genes encoding host immune evasion were positive: cap5, cap8; 55 kinds of virulence genes encoding toxin were positive: hla, hlb, hlg-2, psm-mec, pvl, sea, seb, sec, sed, see, seg, sei, sek, sel, sem, sen, seo, seq, tst, set1, set2, set3, set4, set5, set6, set7, set8, set9, set10, set11, set12, set13, set14, set15, set16, set17, set18, set19, set20, set21, set22, set24, set25, set26, set30 , set31, set32, set33, set34, set35, set36, set38, set39, set40, lukE. In addition, 39 strains of S. aureus were 100.0% susceptible to quinupristin/dalfopristin, rifampin, vancomycin, tigecycline, and had some resistance rates to 12 other kinds of antimicrobial agents. Six resistance genes were positive: mecA (53.8%), aac6'/aph2" (33.3%), aph3'-III (12.8%), ant4'/ant44" (23.1%), qacA (30.8%), bsa (12.8%). Sample cluster analysis suggested that this group of S. aureus were divided into cluster A and B, and presented a clearly aggregation. CONCLUSIONS: A great number of virulence genes were positive in this group of S. aureus, contributing to colonization and survival in the host, evading the host immune system, delivering toxins to the host, and promoting pathogenicities. This group of S. aureus also had high resistance, carried some kinds of resistance genes, and had clustering. The implementation of disinfection measures should be strengthened to prevent the occurrence of nosocomial infection.

Selenium speciation in seleniferous agricultural soils under different cropping systems using sequential extraction and X-ray absorption spectroscopy.

Selenium (Se) speciation in soil is critically important for understanding the solubility, mobility, bioavailability, and toxicity of Se in the environment. In this study, Se fractionation and chemical speciation in agricultural soils from seleniferous areas were investigated using the elaborate sequential extraction and X-ray absorption near-edge structure (XANES) spectroscopy. The speciation results quantified by XANES technique generally agreed with those obtained by sequential extraction, and the combination of both approaches can reliably characterize Se speciation in soils. Results showed that dominant organic Se (56-81% of the total Se) and lesser Se(IV) (19-44%) were observed in seleniferous agricultural soils. A significant decrease in the proportion of organic Se to the total Se was found in different types of soil, i.e., paddy soil (81%) > uncultivated soil (69-73%) > upland soil (56-63%), while that of Se(IV) presented an inverse tendency. This suggests that Se speciation in agricultural soils can be significantly influenced by different cropping systems. Organic Se in seleniferous agricultural soils was probably derived from plant litter, which provides a significant insight for phytoremediation in Se-laden ecosystems and biofortification in Se-deficient areas. Furthermore, elevated organic Se in soils could result in higher Se accumulation in crops and further potential chronic Se toxicity to local residents in seleniferous areas.

The bioavailability of selenium and risk assessment for human selenium poisoning in high-Se areas, China.

Enshi prefecture of Hubei Province is well known for human selenium (Se) poisoning in the early 1960s in China. Sporadic cases of Se poisoning in livestocks are still being found. In this study, Se levels in water, cropland soils and various crops from high-Se areas of Enshi were measured to investigate the distribution and bioavailability of Se in the environments, as well as probable daily intake (PDI) of Se for local residents. The total Se in surface water ranged from 2.0 to 519.3µg/L with a geometric mean of 46.0±127.8 µg/L (n=48), 70.5-99.5% of which was present in the form of Se(VI). The soil Se concentration varied from 2.89 to 87.3 µg/g with a geometric mean of 9.36±18.6 µg/g (n=45), and most of Se was associated with organic matter (OM-Se). The total Se in rice, corn, and vegetable samples were 2.11±2.87 µg/g (n=21), 3.76±11.6 µg/g (n=16), and 2.09±3.38 µg/g (n=25), respectively. Stream water Se is likely leached from carbonaceous shale and mine wastes, leading to Se accumulation in paddy soils. OM-Se may play an important role in Se uptake by rice plant in high-Se area of Enshi. The PDI of Se is approximately 2144 µg/day, and Se concentration in blood is estimated at about 3248 µg/L, posing a potential chronic Se poisoning risk to local residents. Cereal consumption (48.5%) makes a great contribution to human daily Se intake, followed by vegetables (36.6%), meats (8.5%), and drinking water (6.4%). However, when assessing health risk on human in high-Se areas, the contribution of drinking water to daily Se intake cannot be ignored due to high Se content and dominant Se(VI) species. Local inhabitants should be advised not to grow crops in high-Se lands or irrigate using high-Se water. If possible, they should drink pipe water and consume foods mixed with those from outside the high-Se areas.

Selenium in soil inhibits mercury uptake and translocation in rice (Oryza sativa L.).

A great number of studies have confirmed that mercury-selenium (Hg-Se) antagonism is a widespread phenomenon in microorganisms, fish, poultry, humans, and other mammals. However, by comparison, little attention has been paid to plants. To investigate the influence of Se on the uptake and translocation of methylHg/inorganic Hg (MeHg/IHg) in the rice-soil system, we determined the levels of Se, IHg, and MeHg in different parts of rice plants (including the root, stem, leaf, husk, and grain (brown rice)) and corresponding soils of root zones collected from a Hg mined area, where Hg and Se co-occur due to historic Hg mining and retorting activities. The results showed that, in general, the Se levels were inversely related to the levels of both IHg and MeHg in the grains. In addition, a consistent reduction in translocation of both IHg and MeHg in the aerial shoots (i.e., the stem, leaf, husk, and grain) with increasing Se levels in the soils was observed. Furthermore, the Se levels were positively correlated with the IHg levels in the soils and the roots. These results suggest that Se may play an important role in limiting the bioaccessibility, absorption, and translocation/bioaccumulation of both IHg and MeHg in the aerial rice plant, which may be related to the formation of an Hg-Se insoluble complex in the rhizospheres and/or roots.

Cinnamon extract improves fasting blood glucose and glycosylated hemoglobin level in Chinese patients with type 2 diabetes.

For thousands of years, cinnamon has been used as a traditional treatment in China. However, there are no studies to date that investigate whether cinnamon supplements are able to aid in the treatment of type 2 diabetes in Chinese subjects. We hypothesized cinnamon should be effective in improving blood glucose control in Chinese patients with type 2 diabetes. To address this hypothesis, we performed a randomized, double-blinded clinical study to analyze the effect of cinnamon extract on glycosylated hemoglobin A(1c) and fasting blood glucose levels in Chinese patients with type 2 diabetes. A total of 66 patients with type 2 diabetes were recruited and randomly divided into 3 groups: placebo and low-dose and high-dose supplementation with cinnamon extract at 120 and 360 mg/d, respectively. Patients in all 3 groups took gliclazide during the entire 3 months of the study. Both hemoglobin A(1c) and fasting blood glucose levels were significantly reduced in patients in the low- and high-dose groups, whereas they were not changed in the placebo group. The blood triglyceride levels were also significantly reduced in the low-dose group. The blood levels of total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and liver transaminase remained unchanged in the 3 groups. In conclusion, our study indicates that cinnamon supplementation is able to significantly improve blood glucose control in Chinese patients with type 2 diabetes.

Selenium fractions in organic matter from Se-rich soils and weathered stone coal in selenosis areas of China.

A high degree of association between Selenium (Se) and organic matter has been demonstrated in natural environments, but Se fractions and speciation in organic matter is unclear. In this study, a method for quantifying organic matter associated with Se (OM-Se) was developed to investigate Se fractions in organic matter in Se-rich soils and weathered stone coal from Enshi, China, where Se poisoning of humans and livestock has been documented. Initially, Se was extracted using water and a phosphate buffer. Subsequently, OM-Se was extracted using NaOH, and then speciated into Se associated with fulvic acids (FA-Se) and humic acids (HA-Se). Both FA-Se and HA-Se were further speciated into the weakly bound and strongly bound fractions using a customized hydride generation reactor. The results show that FA-Se (1.91-479 mg kg(-1)) is the predominant form of Se in all Se-rich soils and the weathered stone coal samples, accounting for more than 62% of OM-Se (3.07-484 mg kg(-1)). Weakly bound FA-Se (1.33-450 mg kg(-1)) was prevalent in the total FA-Se, while weakly bound HA-Se (0.62-26.2 mg kg(-1)) was variable in the total HA-Se (1.15-32.5 mg kg(-1)). These data indicate that OM-Se could play a significant source and sink role in the biogeochemical cycling of Se in the supergene environment. Weakly bound FA-Se seems to act as a potential source for bioavailable Se, whereas strongly bound HA-Se is a possible OM-Se sink which is not readily transformed into bioavailable Se.

Selenium characterization in the global rice supply chain.

For up to 1 billion people worldwide, insufficient dietary intake of selenium (Se) is a serious health constraint. Cereals are the dominant Se source for those on low protein diets, as typified by the global malnourished population. With crop Se content constrained largely by underlying geology, regional soil Se variations are often mirrored by their locally grown staples. Despite this, the Se concentrations of much of the world's rice, the mainstay of so many, is poorly characterized, for both total Se content and Se speciation. In this study, 1092 samples of market sourced polished rice were obtained. The sampled rice encompassed dominant rice producing and exporting countries. Rice from the U.S. and India were found to be the most enriched, while mean average levels were lowest in Egyptian rice: approximately 32-fold less than their North American equivalents. By weighting country averages by contribution to either global production or export, modeled baseline values for both were produced. Based on a daily rice consumption of 300 g day(-1), around 75% of the grains from the production and export pools would fail to provide 70% of daily recommended Se intakes. Furthermore, Se localization and speciation characterization using X-ray fluorescence (micro-XRF) and X-ray absorption near edge structure (micro-XANES) techniques were investigated in a Se-rich sample. The results revealed that the large majority of Se in the endosperm was present in organic forms.

[Studies on random amplified polymorphic DNA fingerprinting of Cortex Magnoliae Officinalis].

OBJECTIVE: To identify Chinese traditional medicine (CTM) "Hou-pu" (Cortex Magnoliae Officinalis), its counterfeits and substitues. METHODS: Total genomic DNA samples of ten plant species were amplified by randomly amplified polymorphic DNA (RAPD). RESULTS: Ten samples were able to be distinguished through their amplified DNA banding patterns on the agarose gels after electrophoresis. CONCLUSION: RAPD is able to identify "Hou-pu", its counterfeits and substitutes quickly and truly, which is also quite valuable for correctly introducing plant.