Recent studies have reported that graphene oxide (GO) is capable of enhancing the mechanical properties of hardened Portland cement (PC) pastes. The mechanisms proposed so far to explain this ...strengthening generally assume that GO is well dispersed in the pore solution of PC paste, serving as a reinforcing agent or nucleation-growth site during hydration. This paper investigates (i) the effect of GO on the hydration of alite, the main constituent of PC cement, using isothermal calorimetry and boundary nucleation-growth modelling, and (ii) the factors controlling the colloidal stability of GO in alite paste environment. Results indicate that GO accelerates the hydration of alite only marginally, and that GO is susceptible to aggregation in alite paste. This instability is due to (i) a pH-dependent interaction between GO and calcium cations in the pore solution of alite paste, and (ii) a significant reduction of GO functional groups at high pH.
In addition to rusts, the subphylum Pucciniomycotina (Basidiomycota) includes a large number of unicellular or dimorphic fungi which are usually studied as yeasts. Ribosomal DNA sequence analyses ...have shown that the current taxonomic system of the pucciniomycetous yeasts which is based on phenotypic criteria is not concordant with the molecular phylogeny and many genera are polyphyletic. Here we inferred the molecular phylogeny of 184 pucciniomycetous yeast species and related filamentous fungi using maximum likelihood, maximum parsimony and Bayesian inference analyses based on the sequences of seven genes, including the small subunit ribosomal DNA (rDNA), the large subunit rDNA D1/D2 domains, the internal transcribed spacer regions (ITS 1 and 2) of rDNA including the 5.8S rDNA gene; the nuclear protein-coding genes of the two subunits of DNA polymerase II (RPB1 and RPB2) and the translation elongation factor 1-α (TEF1); and the mitochondrial gene cytochrome b (CYTB). A total of 33 monophyletic clades and 18 single species lineages were recognised among the pucciniomycetous yeasts employed, which belonged to four major lineages corresponding to Agaricostilbomycetes, Cystobasidiomycetes, Microbotryomycetes and Mixiomycetes. These lineages remained independent from the classes Atractiellomycetes, Classiculomycetes, Pucciniomycetes and Tritirachiomycetes formed by filamentous taxa in Pucciniomycotina. An updated taxonomic system of pucciniomycetous yeasts implementing the ‘One fungus = One name’ principle will be proposed based on the phylogenetic framework presented here.
Vitrification from physical vapor deposition is known to be an efficient way for tuning the kinetic and thermodynamic stability of glasses and significantly improve their properties. There is a ...general consensus that preparing stable glasses requires the use of high substrate temperatures close to the glass transition one, T
. Here, we challenge this empirical rule by showing the formation of Zr-based ultrastable metallic glasses (MGs) at room temperature, i.e., with a substrate temperature of only 0.43T
. By carefully controlling the deposition rate, we can improve the stability of the obtained glasses to higher values. In contrast to conventional quenched glasses, the ultrastable MGs exhibit a large increase of T
of ∼60 K, stronger resistance against crystallization, and more homogeneous structure with less order at longer distances. Our study circumvents the limitation of substrate temperature for developing ultrastable glasses, and provides deeper insight into glasses stability and their surface dynamics.
•Discusses the ingress and distribution of chloride ions in concretes subjected to carbonation.•Influence of carbonation and its extent on both the ingress and redistribution of ...chlorides.•Interactions between carbonation and chloride ingress for different types of binders.•Relevance of combined effects of carbonation and chloride ingress to service life prediction.
In majority of exposure environments for concrete structures, there is a high probability of the cyclic occurence of both chloride ingress and carbonation. This paper reports a detailed investigation on the influence of carbonation on both the ingress and distribution of chlorides in three different types of concretes, by comparing results from exposure to chlorides, chlorides before carbonation and chlorides after carbonation. Concretes studied were of 0.55 water-binder ratio with 100% Portland Cement (PC), 70% PC+30% pulverized fuel ash (PFA) and 85% PC+10% PFA+5% microsilica (MS) as binders. Chloride profiles were compared to assess the effects of all variables studied in this research. The effect of carbonation was quantified by measuring the consumption of hydroxyl ions (OH−), air permeability and chloride migration coefficient. The results indicated that carbonation of concrete increases chloride transport, but the precise nature of this is dependent on the combined regime as well as the type of binder. In general, it was found that carbonation of chloride contaminated concretes results in a decrease of their chloride binding capacity, that is it releases the bound Cl− in concretes and pushes chlorides inwards, as has been established previously by other researchers. However, it is established in this research that the combined regimes detrimentally affect the service life of concrete structures, particularly when chloride induced corrosion is a concern.
Increasing grazing pressure and climate change affect nitrogen (N) dynamics of grassland ecosystems in the Eurasian steppe belt with unclear consequences for future delivery of essential services ...such as forage production, C sequestration, and diversity conservation. The identification of key processes responsive to grazing is crucial to optimize grassland management. In this comprehensive case study of a Chinese typical steppe, we present an in-depth analysis of grazing effects on N dynamics, including the balance of N gains and losses, and N cycling. N pools and fluxes were simultaneously quantified on three grassland sites of different long-term grazing intensities.
Dust deposition, wind erosion, and wet deposition were the predominant but most variable processes contributing to N losses and gains. Heavy grazing increased the risk of N losses by wind erosion. Hay-making and sheep excrement export to folds during nighttime keeping were important pathways of N losses from grassland sites. Compared to these fluxes, gaseous N losses (N
2
O, NO, N
2
, and NH
3
) and N losses via export of sheep live mass and wool were of minor relevance. Our N balance calculation indicated mean annual net N losses of 0.9 ± 0.8 g N/m
2
(mean ± SD) at the heavily grazed site, whereas the long-term ungrazed site was an N sink receiving mean annual inputs of 1.8 ± 1.1 g N/m
2
, mainly due to dust deposition. Heavy grazing reduced pool sizes of topsoil organic N, above- and belowground biomass, and N fluxes with regard to plant N uptake, decomposition, gross microbial N turnover, and immobilization. Most N-related processes were more intensive in seasons of higher water availability, indicating complex interactions between land use intensity and climate variability. The projected increase of atmospheric N depositions and changes in rainfall pattern imposed by land use change will likely affect N sink-source pathways and N flux dynamics, indicating high potential impact on grassland ecosystem functions. Land use practices will be increasingly important for the management of N dynamics in Chinese typical steppe and, therefore, must be considered as key component to maintain, restore or optimize ecosystem services.
Objectives
Dietary protein intake is of great significance for the bone health of middle-aged and elderly people. This study is aimed to explore the relationships between dietary protein intake and ...the risk of osteoporosis in middle-aged and older individuals among US population.
Methods
Based on the National Health and Nutrition Examination Survey (NHANES), this study includes a total of 20497 participants during 2005–2008, and identify 4707 middle-aged and older people aged 45 years or above. Demographic data and relevant dietary intake information are acquired through in-home management questionnaires. The logistic regression models are established to identify the odds ratio (OR) and 95% confidence interval (CI) of OP in each quartile category of energy-adjusted dietary protein intake. The receiver operating characteristic (ROC) curve is applied to explore the optimal cut-off value of daily dietary protein intake for predicting risk of OP.
Results
442 participants with OP are identified among 4707 middle-aged and older people, and the dietary protein intake of OP group is significantly lower than that of non-OP group (P<0.001). The logistic regression analysis shows that with the increase of daily dietary protein intake, the prevalence of OP in each quartile category decreases gradually (P<0.001). This trend is not altered in univariate model (P<0.001), as well as the adjustments for the covariates of age and BMI (Model 1, P<0.001), the covariates of sex (Model 2, P=0.036), the covariates of smoking, drinking alcohol, education, ratio of family income to poverty, hypertension and diabetes (Model 3, P<0.001), and the covariates of dietary intake (Model 4, P=0.008). Moreover, we also identify that the daily dietary protein intake of 61.2g is the optimal cut-off value for predicting risk of OP.
Conclusion
In general, among US population, the lower daily dietary protein intake is positively related to the ascending risk of OP in middle-aged and older individuals.
Summary
Senecavirus A (SVA) infection was recently confirmed in pigs in Brazil. In March, 2015, an outbreak of vesicular disease occurred in Guangdong, China, characterized by vesicular lesions in ...sows and acute death of neonatal piglets. Cumulative incidence of porcine idiopathic vesicular disease in farm A was 258, which had a total number of 5500 sows. Sows in farm B displayed typical vesicular symptoms by May, 2015, which also had 5500 sows. A total of 278 and 142 of 5500 sows in farm B demonstrated lame and presented vesicles, respectively, associated with a total of 186 mortality in piglets. Routine differential diagnoses for swine vesicular disease were carried out to exclude infection with foot‐and‐mouth disease virus, swine vesicular disease virus, vesicular exanthema of swine virus and vesicular stomatitis virus. In this study, seven pairs of primer were designed to amplify the complete genome of SVA in RT‐PCR assays. Sequence alignment showed that this Chinese strain shares 94.4–97.1% sequence identity to other eight strains of SVA. This is the first report of SVA in China and provides information about the association between SVA infection and vesicular disease.
Exposure to environmental endocrine-disrupting chemicals during pregnancy reportedly causes transgenerationally inherited reproductive defects. We hypothesized that to affect the grandchild, ...endocrine-disrupting chemicals must alter the epigenome of the germ cells of the in utero-exposed G1 male fetus. Additionally, to affect the great-grandchild, the aberration must persist in the germ cells of the unexposed G2 grandchild.
Here, we treat gestating female mice with vinclozolin, bisphenol A, or di-(2-ethylhexyl)phthalate during the time when global de novo DNA methylation and imprint establishment occurs in the germ cells of the G1 male fetus. We map genome-wide features in purified G1 and G2 prospermatogonia, in order to detect immediate and persistent epigenetic aberrations, respectively. We detect changes in transcription and methylation in the G1 germline immediately after endocrine-disrupting chemicals exposure, but changes do not persist into the G2 germline. Additional analysis of genomic imprints shows no persistent aberrations in DNA methylation at the differentially methylated regions of imprinted genes between the G1 and G2 prospermatogonia, or in the allele-specific transcription of imprinted genes between the G2 and G3 soma.
Our results suggest that endocrine-disrupting chemicals exert direct epigenetic effects in exposed fetal germ cells, which are corrected by reprogramming events in the next generation. Avoiding transgenerational inheritance of environmentally-caused epigenetic aberrations may have played an evolutionary role in the development of dual waves of global epigenome reprogramming in mammals.
Antioxidant and estrogenic effects of formononetin on ovariectomized mice have been investigated in the present study. The adult female Kunming mice were divided into 5 groups: sham-operated group, ...ovariectomized group, stilbestrol replacement therapy group (0.20
mg/kg
day), low-dose formononetin group (0.05
g/kg
day) and high-dose formononetin group (0.5
g/kg
day). The mice in the latter 4 groups were ovariectomized. The drug was given by oral administration for 6 months. Estrogenic effect was determined by the change of uterine weight, and oxidant effects were determined by the content of SOD, GSH-Px, CAT and MDA. The intake of formononetin increased the uterine weight of the mice significantly as well as the content of SOD, GSH-Px, CAT, and reduced MDA in body. Formononetin had obvious antioxidant effects and estrogenic effect, and the estrogenic effect was not dosage-related.
Contrary to the formation of complicated polycrystals induced by general crystallization, a modulated superlatticelike nanostructure, which grows layer by layer from the surface to the interior of a ...Pd_{40}Ni_{10}Cu_{30}P_{20} metallic glass, is observed via isothermal annealing below the glass transition temperature. The generation of the modulated nanostructure can be solely controlled by the annealing temperature, and it can be understood based on the fast dynamic and liquidlike behavior of the glass surface. The observations have implications for understanding the glassy surface dynamics and pave a way for the controllable fabrication of a unique and sophisticated nanostructure on a glass surface to realize the properties' modification.
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