As part of a project on phytoextraction of lead (Pb) in paddy soils around a lead/zinc (Pb/Zn) Mine in Lechang of Guangdong Province, South China, the concentration distribution of Pb in paddy ...soil–rice system was investigated, and its potential health risk to animal/human was evaluated. Total and diethylenetetraminepentaacetic acid (DTPA)-extractable Pb in soils averaged 1486 and 268 μg/g, respectively. According to sequential extraction procedure, soil Pb occurred primarily in the residual, carbonate and exchangeable fractions (30.2%, 26.7% and 19.1%, respectively). Lead extracted by the gastric juice simulation test (GJST) was 1068 μg/g and accounted for 75.4% of the total concentration. Mean Pb concentrations of 419 μg/g in rice root, 69.1 μg/g in whole straw, 51.0 μg/g in part straw (without two leaves near above the root), 44.9 μg/g in stalk, 21.9 μg/g in hull, 13.2 μg/g in grain with hull and 4.67μg/g in grain without hull (namely, unpolished rice) were found. Lead concentrations in both soil and rice plant were far above the corresponding tolerable levels. Lead daily intakes by local residents were 2.6 mg for adults and 1.2 mg for children, which were much higher than the allowable level. Thus, Pb in this area might pose a potential health risk to the local population.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Chlorophylls are vital for photosynthesis, allowing plants to absorb energy from light for photosynthesis. More than one hundred species of chlorophyll have been identified. Among them, chlorophylls ...a, b, c (c1, c2, and c3), d, and f exist in oxygenic photosynthetic organisms (e.g., higher plants, algae, and cyanobacteria), whereas anoxygenic photosynthetic bacteria possess bacteriochlorophylls a, b, c, d, e, and g. These chlorophylls have different chemical structures and properties that enable photosynthetic organisms to perform photosynthesis in different environments. All of the chlorophylls are biosynthesized from 3,8-divinyl-protochlorophyllide a by a series of enzymes. The synthetic pathways of chlorophylls have now been basically clarified. This review succinctly summarizes the structures, properties, and synthetic pathways of the chlorophylls.
Blueberries belong to the genus Vaccinium of the family Ericaceae. A series of epidemiological studies have demonstrated that blueberry polyphenols, particularly blueberry anthocyanins provide ...significant beneficial effects for humans. However, the findings of clinical studies have been equivocal. Therefore, we sought to assess the potential anti-hypertensive effects of blueberry supplementation through a meta-analysis of available randomized controlled trials (RCTs). A comprehensive literature search of PubMed, The Cochrane Library, AMED (Allied and Complementary Medicine Database), Embase, Web of Science, Wanfang Database, and China National Knowledge Infrastructure were performed to identify potential studies published before June 2015. The standardized mean difference and 95% confidence interval (CI) were used as summary statistics. Net changes in systolic blood pressure (SBP) and diastolic blood pressure (DBP) between the blueberry and placebo groups were calculated by subtracting the values at the end of follow-up from those at baseline. Meta-regression was used to identify potential moderators of effect size. Six RCT studies with 204 participants were included in our meta-analysis. There was no significant effect of blueberry supplementation on changes in blood pressure (BP) relative to baseline, and there was a mean difference of -0.28 (95% CI: -1.11 to 0.56, I
=87%) and -0.5 (95% CI: -1.24 to 0.24, I
=84%) mmHg for SBP and DBP, respectively. In summary, the results from this meta-analysis do not favor any clinical efficacy of blueberry supplementation in improving BP. Further well-designed larger RCTs are required to verify the association between blueberry supplementation and BP.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
We carried out a randomized multicentre study in China to investigate whether the clofazimine would improve the efficacy of the standardized regimen in patients with multidrug-resistant tuberculosis ...(MDR-TB).
Patients with MDR-TB managed in 17 TB specialist hospitals in China between September 2009 and September 2011 were randomly assigned to the treatment groups at enrolment. In the intervention group, 100 mg clofazimine per day was added to the standardized regimen. The primary outcome was the proportion of patients with successful outcomes.
From the 156 patients that were screened, 74 were assigned to the control group and 66 to the clofazimine group. Of the 66 cases analysed for clinical outcome in the clofazimine group, 36 patients were cured, and seven completed treatment, yielding a favourable outcome rate of 65.1%. The proportion of patients with favourable outcomes receiving the control regimen was 47.3% (35/74), which was significantly lower than that in the clofazimine group (p 0.034, relative risk 0.661, 95% CI 0.243–0.949).
The addition of clofazimine to the standard regimen improved the treatment of MDR-TB.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Formaldehyde (FA) is an economically important industrial chemical to which millions of people worldwide are exposed environmentally and occupationally. Recently, the International Agency for Cancer ...Research concluded that there is sufficient evidence that FA causes leukemia, particularly myeloid leukemia. To evaluate the biological plausibility of this association, we employed a chromosome-wide aneuploidy study approach, which allows the evaluation of aneuploidy and structural chromosome aberrations (SCAs) of all 24 chromosomes simultaneously, to analyze cultured myeloid progenitor cells from 29 workers exposed to relatively high levels of FA and 23 unexposed controls. We found statistically significant increases in the frequencies of monosomy, trisomy, tetrasomy and SCAs of multiple chromosomes in exposed workers compared with controls, with particularly notable effects for monosomy 1 P = 6.02E-06, incidence rate ratio (IRR) = 2.31, monosomy 5 (P = 9.01E-06; IRR = 2.24), monosomy 7 (P = 1.57E-05; IRR = 2.17), trisomy 5 (P = 1.98E-05; IRR = 3.40) and SCAs of chromosome 5 (P = 0.024; IRR = 4.15). The detection of increased levels of monosomy 7 and SCAs of chromosome 5 is particularly relevant as they are frequently observed in acute myeloid leukemia. Our findings provide further evidence that leukemia-related cytogenetic changes can occur in the circulating myeloid progenitor cells of healthy workers exposed to FA, which may be a potential mechanism underlying FA-induced leukemogenesis.
Tree trunk cankers represent serious fungal diseases that pose significant threats to Chinese hickory trees (
). To characterize the pathogen diversity associated with this disease, tissues were ...collected between 2016 and 2018 from the primary Chinese hickory plantation regions. A total of 97 cultures were isolated from trees in six towns (Longgang, Qingliangfeng, Changhua, Tuankou, Taiyang Town, and Lin'an urban area) within the Linan district, where 60% of Chinese hickory tree yields originate. The isolated cultures caused cankers on Chinese hickory tree branches, but infections did not occur on fruits or leaves under tested conditions. Combined morphological observations and phylogenetic analysis of multiple genes (
, β-
, and
) indicated that five
species were recovered, including 89 isolates of
, 4 isolates of
, 1 isolate of
, 1 isolate of
, and two isolates of
.
.
was the most prevalent, and this is the first report of
.
,
.
, and
.
infections in Chinese hickory trees. We investigated the mycelial growth, spore germination, and pathogenicity of these species at different temperatures.
.
grew the fastest and
.
grew the slowest on potato dextrose agar. The optimum temperature of spore germination for all species was 30°C.
.
was the most virulent species, followed by
.
and
.
, then
.
, and finally
.
. These new insights into fungal pathogen diversity provide critical new information to understand and manage tree trunk cankers of Chinese hickory.
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•The model can be used for the determination of optimised process parameters.•Powder particle distribution is important for simulating laser-powder interaction.•Pores and uneven ...surface are exacerbated by increased powder layer thickness.•The use of an argon atmosphere did not affect the single track morphology.•The predicted microstructure is dependent upon localised solidification conditions.
In this paper, an integrated computational materials science approach for selective laser melting (SLM) at the mesoscale is presented. A particle dropping model was developed to simulate the representative powder-bed particle distribution of a measured titanium alloy powder. Thermal fluid flow and resulting microstructural evolution of a set of laser scanned single tracks with different powder layer thicknesses and scanning speeds during SLM were also studied using both computational and experimental approaches. The simulated powder particle distribution was found to be consistent with experimental measurement. The thermal fluid flow model predicts that single laser scanned tracks become increasingly irregular-shaped with increased powder layer thickness and increased laser scanning speed. These findings were reinforced by scanning electron microscopy analysis. The more dispersed dissipation of the localised heat for thicker powder layers is understood to cause increased melting and evaporation. This can lead to increased Marangoni force and recoil pressure which in turn destabilises the melt flow. The use of an argon atmosphere speeds up the solidification process when compared with air but does not affect the morphology of single tracks significantly. The predicted microstructure was consistent with the electron backscattered diffraction data. The microstructure-based modelling methodology considering the representative powder size distribution provides a good predictive capability for the laser-powder interaction behaviour, surface structure and porosity development.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Context.
Fast radio bursts (FRBs) are extremely energetic pulses of millisecond duration and unknown origin. To understand the phenomenon that emits these pulses, targeted and un-targeted searches ...have been performed for multiwavelength counterparts, including the optical.
Aims.
The objective of this work is to search for optical transients at the positions of eight well-localized (< 1″) FRBs after the arrival of the burst on different timescales (typically at one day, several months, and one year after FRB detection). We then compare this with known optical light curves to constrain progenitor models.
Methods.
We used the Las Cumbres Observatory Global Telescope (LCOGT) network to promptly take images with its network of 23 telescopes working around the world. We used a template subtraction technique to analyze all the images collected at differing epochs. We have divided the difference images into two groups: In one group we use the image of the last epoch as a template, and in the other group we use the image of the first epoch as a template. We then searched for optical transients at the localizations of the FRBs in the template subtracted images.
Results.
We have found no optical transients and have therefore set limiting magnitudes to the optical counterparts. Typical limits in apparent and absolute magnitudes for our LCOGT data are ∼22 and −19 mag in the
r
band, respectively. We have compared our limiting magnitudes with light curves of super-luminous supernovae (SLSNe), Type Ia supernovae (SNe Ia), supernovae associated with gamma-ray bursts (GRB-SNe), a kilonova, and tidal disruption events (TDEs).
Conclusions.
Assuming that the FRB emission coincides with the time of explosion of these transients, we rule out associations with SLSNe (at the ∼99.9% confidence level) and the brightest subtypes of SNe Ia, GRB-SNe, and TDEs (at a similar confidence level). However, we cannot exclude scenarios where FRBs are directly associated with the faintest of these subtypes or with kilonovae.
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