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To characterize the association of longitudinal changes in maternal anthropometric measures with neonatal anthropometry and to assess to what extent late-gestational changes in maternal anthropometry are associated with neonatal body composition.
In a prospective cohort of pregnant women, maternal anthropometry was measured at six study visits across pregnancy and after birth, neonates were measured and fat and lean mass calculated. We estimated maternal anthropometric trajectories and separately assessed rate of change in the second (15–28 weeks) and third trimester (28–39 weeks) in relation to neonatal anthropometry. We investigated the extent to which tertiles of third-trimester maternal anthropometry change were associated with neonatal outcomes.
Women were recruited from twelve US sites (2009–2013).
Non-obese women with singleton pregnancies (n 2334).
A higher rate of increase in gestational weight gain was associated with larger-birth-weight infants with greater lean and fat mass. In contrast, higher rates of increase in maternal anthropometry measures were not associated with infant birth weight but were associated with decreased neonatal lean mass. In the third trimester, women in the tertile of lowest change in triceps skinfold (−0·57 to −0·06 mm per week) had neonates with 35·8 g more lean mass than neonates of mothers in the middle tertile of rate of change (−0·05 to 0·06 mm per week).
The rate of change in third-trimester maternal anthropometry measures may be related to neonatal lean and fat mass yet have a negligible impact on infant birth weight, indicating that neonatal anthropometry may provide additional information over birth weight alone.
Organic compounds such as azo dyes have been detected in wastewater due to their use in industries without regulation. Conventional wastewater treatments are not always effective in the removal of these pollutants. Among the innovative materials that deal with this problem, are the polymer-zeolitic composites used as adsorbents. Modified natural zeolites have been proven to be efficient for the removal of yellow 6; on the other hand, biopolymers such as alginate offer their potential use as a polymer matrix for the synthesis of biocomposites. In this study, the adsorbent properties of a ferric zeolite and an alginate-ferric zeolite composite were determined for the removal of yellow 6 dye from aqueous solutions. The X-ray diffraction (XRD) results of both natural and modified zeolites indicated the presence of clinoptilolite. The characteristic bands of these materials were identified through the Fourier Transform Infrared Spectroscopy (FTIR) technique. Moreover, the presence of iron in the ferrous zeolite was verified by elemental analysis (EDS). Adsorption tests showed that the composite has a lower removal capacity than the zeolitic material; however, in the case of water treatment systems, the composite would be easier to handle than the zeolite without supporting it in a polymer matrix.
The aim of this research was to investigate the influence of substrate roughness on the adhesion and tribological performance of thin TiN coatings obtained by physical vapor deposition. For that purpose, substrates of AISI H13 steel with surface finishes of 0.06, 0.28 and 0.90 μm in Ra were coated with TiN under the same coating conditions. The chemical composition of the steel, as well as that of the TiN coating, were obtained using EDS analysis. Adhesion tests were carried out following the procedure of BSi 1071-8 standard while hardness was evaluated by ASTM C 1327-03. On the other hand, dry sliding friction tests were conducted with a pin-on-disk tribometer, according to the ASTM G 99-05 standard. This study showed that the roughness of the coating increases as the substrate roughness increases. Regarding adhesion and hardness, all the samples showed an adhesion class 1 according to the standard and a hardness value of 14.51 GPa. Nevertheless, the highest substrate roughness produced the best adhesion. On the other hand, the lowest values for the friction coefficient and wear behavior were obtained by the sample with the lowest substrate roughness of 0.06 µm. In addition, it was found that friction and wear increase when the substrate roughness increases.
This is the first report on the development and characterization of eight monoclonal antibodies (MABs) generated against whole- and membrane-enriched tachyzoite extracts of the apicomplexan parasite Besnoitia besnoiti. Confocal laser scanning immunofluorescence microscopy was used to localize respective epitopes in B. besnoiti tachyzoites along the lytic cycle. A pattern compatible with dense granule staining was observed with MABs 2.A.12, 2.F.3 and 2.G.4, which could be confirmed by immunogold electron microscopy for MABs 2.A.12 and 2.F.3. In particular, MABs 2.F.3 and 2.G.4 were secreted during early invasion, proliferation and egress phases. MABs 3.10.8 and 5.5.11 labelled the tachyzoite surface, whilst MABs 1.17.8, 8.9.2 and 2.G.A recognized the apical tip, which is reminiscent for microneme localization. Besides, the epitopes recognized by the latter two (MABs 8.9.2 and 2.G.A) exhibited a redistribution from the anterior part across the parasite surface towards the posterior end during invasion. Most MABs developed were genus-specific. Indeed, the MABs cross-reacted neither with T. gondii nor with N. caninum tachyzoites. In summary, we have generated MABs that will be useful to study the key processes in the lytic cycle of the parasite and with additional promising diagnostic value. However, the molecular identity of the antigens recognized remains to be elucidated.
A novel method to perform small-scale laboratory experiments that reproduce concrete–bentonite and concrete–groundwater interactions has been developed. Such interfaces will prevail in engineered barrier systems used for isolation of nuclear waste. With the goal of optimizing the experimental method, this work has analysed the geochemical interaction of distilled water, low-pH cement mortar and FEBEX-bentonite for 75 days. Limited but evident reactivity between the materials was observed, mainly decalcification in cement mortar, carbonation at the interface with bentonite and Mg enrichment in bentonite. These results are consistent with the state-of-the-art literature and were used to validate this small-scale pilot laboratory experiment to establish the basis for further studies comparing the behaviour of different buffer and cement materials.
The ability to interface electronic materials with the peripheral nervous system is required for stimulation and monitoring of neural signals. Thus, the design and engineering of robust neural interfaces that maintain material-tissue contact in the presence of material or tissue micromotion offer the potential to conduct novel measurements and develop future therapies that require chronic interface with the peripheral nervous system. However, such remains an open challenge given the constraints of existing materials sets and manufacturing approaches for design and fabrication of neural interfaces. Here, we investigated the potential to leverage a rapid prototyping approach for the design and fabrication of nerve cuffs that contain supporting features to mechanically stabilize the interaction between cuff electrodes and peripheral nerve. A hybrid 3D printing and robotic-embedding (i.e., pick-and-place) system was used to design and fabricate silicone nerve cuffs (800 µm diameter) containing conforming platinum (Pt) electrodes. We demonstrate that the electrical impedance of the cuff electrodes can be reduced by deposition of the conducting polymer poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) on cuff electrodes via a post-processing electropolymerization technique. The computer-aided design and manufacturing approach was also used to design and integrate supporting features to the cuff that mechanically stabilize the interface between the cuff electrodes and the peripheral nerve. Both ‘self-locking’ and suture-assisted locking mechanisms are demonstrated based on the principle of making geometric alterations to the cuff opening via 3D printing. Ultimately, this work shows 3D printing offers considerable opportunity to integrate supporting features, and potentially even novel electronic materials, into nerve cuffs that can support the design and engineering of next generation neural interfaces.
The objective of this work was to determine the rumen degradation characteristics over the growing season of maize stover in two contrasting zones in the central highlands of Mexico. Twenty four maize plots were selected, three harvest periods P1, P2, and P3 were established in order to evaluate degradation characteristics at different development stages, for ‘criollo’ maize varieties of three grain colours (white, yellow and black) representing different cultivation practices given their different growing cycles. In vitro gas production (GP) incubations were carried out, and cumulative gas volumes were fitted to the Krishnamoorthy, Soller, Steingass and Menke (1991) model. The results indicate that more research is needed to evaluate why maize degradability and fermentation characteristics as exemplified by this work are not greatly affected by time.
Polycyclic aromatic hydrocarbons are increasingly widespread pollutants introduced into the environment via oil spillage and incomplete anthropogenic combustion of fossil fuels. In this work, the capacity of stevensite and sepiolite to adsorb phenanthrene (PHE) has been evaluated experimentally by batch testing. Both clay minerals are distributed widely in the Madrid Basin, are of low cost and can be applied with minimal environmental impact. In the context of few previous studies, adsorption isotherms have been developed to understand the adsorption mechanisms and were fitted to the Freundlich and linear models with virtually the same results. Although stevensite showed greater adsorption capacity than sepiolite, the isotherms were constructed for equilibrium concentrations up to 0.8–1.0 mg/L due to the low solubility of PHE in water. When compared to other adsorbents the ability of stevensite to retain PAHs should be examined further in order to add and complement novel functions in reactive barriers.
This paper introduces GLINTS, a graphical tool for exploring variant narrowing computations in Maude. The most recent version of Maude, version 2.7.1, provides quite sophisticated unification features, including order-sorted equational unification for convergent theories modulo axioms such as associativity, commutativity, and identity. This novel equational unification relies on built-in generation of the set of variants of a term t, i.e., the canonical form of tσ for a computed substitution σ. Variant generation relies on a novel narrowing strategy called folding variant narrowing that opens up new applications in formal reasoning, theorem proving, testing, protocol analysis, and model checking, especially when the theory satisfies the finite variant property, i.e., there is a finite number of most general variants for every term in the theory. However, variant narrowing computations can be extremely involved and are simply presented in text format by Maude, often being too heavy to be debugged or even understood. The GLINTS system provides support for (i) determining whether a given theory satisfies the finite variant property, (ii) thoroughly exploring variant narrowing computations, (iii) automatic checking of node embedding and closedness modulo axioms, and (iv) querying and inspecting selected parts of the variant trees.
A global array of 20 radio observatories was used to measure the three-dimensional position and velocity of the two meteorological balloons that were injected into the equatorial region of the Venus atmosphere by the VEGA spacecraft.
‘Special reduction’ refers to instances of extreme phonetic reduction which is restricted to particular words or phrases, usually grammaticalizing constructions (going to > [gə̃ɾ̃ə̃]), greetings (hi from how are you), discourse markers (Spanish o sea > sa), or other sequences that are often used together. On the basis of data from English, Brazilian Portuguese, and Colombian Spanish, we argue that special reduction is based on the general phonetic tendencies in the language, but that these tendencies are carried to an extreme where word sequences are used with high frequency and become chunked, allowing formerly stressed syllables to lose stress and reduce. The data also show that special reduction takes place gradually over time, and reflects general patterns of change seen in the history of the language. In fact, in some examples, special reduction presages more general sound changes that occur later. We argue that the gradual phonetic changes that accumulate for particular words or phrases, eventually changing them dramatically, requires an exemplar model for the phonological representation of words and phrases, which is updated continually as sequences are used and affected by reductive phonetic processes.
Colistin resistance mediated by the mcr-1 gene has been reported worldwide, but to date not from the Andean region, South America. We report the first clinical isolate of Escherichia coli harbouring the mcr-1 gene in Ecuador. The strain was isolated from peritoneal fluid from a 14-year-old male with acute appendicitis, and subjected to molecular analysis. The minimum inhibitory concentration of colistin for the strain was 8 mg/ml and it was susceptible to carbapenems but resistant to tigecycline. The strain harboured mcr-1 and blaCTX-M-55 genes and was of sequence type 609. The recognition of an apparently commensal strain of E. coli harbouring mcr-1 serves as an alert to the presence in the region of this recently described resistance mechanism to one of the last line of drugs available for the treatment of multi-resistant Gram-negative infections.
Control of fire was a hallmark of developing human cognition and an essential technology for the colonisation of cooler latitudes. In Europe, the earliest evidence comes from recent work at the site of Cueva Negra del Estrecho del Río Quípar in south-eastern Spain. Charred and calcined bone and thermally altered chert were recovered from a deep, 0.8-million-year-old sedimentary deposit. A combination of analyses indicated that these had been heated to 400–600°C, compatible with burning. Inspection of the sediment and hydroxyapatite also suggests combustion and degradation of the bone. The results provide new insight into Early Palaeolithic use of fire and its significance for human evolution.
Carbon nanotubes (CNTs) were synthesized by Chemical Vapor Deposition (CVD) from diethyl ether, butanol, hexane and ethyl acetate. A quartz tube with a stainless steel tube catalyst core with 0.019 m diameter and 0.6 m large formed the reactor. To avoid combustion, argon was used as the carrier gas. Time process ranged 30 to 60 min. The range of CNTs synthesis temperature was 680-850 °C for different precursors. Scanning Electron Microscopy micrographs have demonstrated tangled CNTs growth in all samples, thus presenting difficult length measurement. The CNTs diameters from diethyl ether are 45-200 nm, butanol diameter range from 55-230 nm, hexane diameter range is 50-130 nm and ethyl acetate range from 100 to 300 nm. Carbon content for all samples was higher than 93 %, CNTs from butanol showed carbon concentration up to 99%. FTIR, Raman and X-Ray Spectroscopies spectra for all samples demonstrated the characteristics signals present in carbon nanotubes. This research proposes a simple, effective and innovative method to synthesize CNTs by CVD on iron stainless steel catalyst in combination with diethyl ether, ethyl acetate, butanol and hexane as precursors by applying the principles of green chemistry, sustainability and its ease to be scaled.
Prior research has suggested benefits of aerobic physical activity (PA) on cognition and brain volumes in HIV uninfected (HIV-) individuals, however, few studies have explored the relationships between PA and brain integrity (cognition and structural brain volumes) in HIV-infected (HIV+) individuals. Seventy HIV+ individuals underwent neuropsychological testing, structural neuroimaging, laboratory tests, and completed a PA questionnaire, recalling participation in walking, running, and jogging activities over the last year. A PA engagement score of weekly metabolic equivalent (MET) hr of activity was calculated using a compendium of PAs. HIV+ individuals were classified as physically active (any energy expended above resting expenditure, n=22) or sedentary (n=48). Comparisons of neuropsychological performance, grouped by executive and motor domains, and brain volumes were completed between groups. Physically active and sedentary HIV+ individuals had similar demographic and laboratory values, but the active group had higher education (14.0 vs. 12.6 years, p=.034). Physically active HIV+ individuals performed better on executive (p=.040, unadjusted; p=.043, adjusted) but not motor function (p=.17). In addition, among the physically active group the amount of physical activity (METs) positively correlated with executive (Pearson’s r=0.45, p=0.035) but not motor (r=0.21; p=.35) performance. In adjusted analyses the physically active HIV+ individuals had larger putamen volumes (p=.019). A positive relationship exists between PA and brain integrity in HIV+ individuals. Results from the present study emphasize the importance to conduct longitudinal interventional investigation to determine if PA improves brain integrity in HIV+ individuals. (JINS, 2015, 21, 880–889)
RNA polymerase III (Pol III) synthesizes small RNA molecules that are essential for cell viability. Accurate initiation of transcription by Pol III requires general transcription factor TFIIIB, which is composed of three subunits: TFIIB-related factor BRF1, TATA-binding protein and BDP1. Here we report the molecular characterization of BRF1 in Trypanosoma brucei (TbBRF1), a parasitic protozoa that shows distinctive transcription characteristics. In silico analysis allowed the detection in TbBRF1 of the three conserved domains located in the N-terminal region of all BRF1 orthologues, namely a zinc ribbon motif and two cyclin repeats. Homology modelling suggested that, similarly to other BRF1 and TFIIB proteins, the TbBRF1 cyclin repeats show the characteristic structure of five α-helices per repeat, connected by a short random-coiled linker. As expected for a transcription factor, TbBRF1 was localized in the nucleus. Knock-down of TbBRF1 by RNA interference (RNAi) showed that this protein is essential for the viability of procyclic forms of T. brucei, since ablation of TbBRF1 led to growth arrest of the parasites. Nuclear run-on and quantitative real-time PCR analyses demonstrated that transcription of all the Pol III-dependent genes analysed was reduced, at different levels, after RNAi induction.