This study aimed to determine the suitability of several organic waste substrates to be processed by the larvae of the black soldier fly, Hermetia illucens (L.) (Diptera: Stratiomyidae) (BSFL) in a ...value-added bioconversion system. Three types of organic waste (brewer's waste, solid phase of pig manure, and semidigested grass) were tested and compared with a standard larval diet, broll (wheat middling). Larval survival and growth, chemical composition of the resulting prepupae, conversion ratios of nutrients and waste dry matter, and waste reduction rate were measured. Larval survival was high in all tested substrates. Compared with the larvae fed pig manure or semidigested grass, those fed standard diet or brewer's waste showed shorter development time, higher weight gain, and higher prepupal crude protein and crude fat content. BSFL also reduce more dry matter in the standard diet or in brewer's waste than in the other two substrates. On the other hand, larvae fed semidigested grass took 70 d to complete development and suffered fat loss. Thus, we suggest that brewer's waste is the most suitable substrate among the selected wastes for being processed by BSFL, whereas semidigested grass is an unsuitable substrate. We found that lignin had a significantly negative effect on larval growth, and emphasized the importance of applying lignindigesting microorganisms to lignin-rich substrates being converted by BSFL. Moreover, a protein:fat:digestible carbohydrate ratio of 2:1:2 was hypothesized to benefit larval development.
Wheat gluten/glycerol-based materials were reinforced through natural fiber addition. Hemp and wood fiber addition increased both composite tensile strength and Young’s modulus, but decreased ...elongation at break. Resulting materials exhibited lower water sensitivity. Fiber addition does not modify the protein aggregation, but resulted in an increase of the composite matrix glass transition temperature (Tg). This increase was attributed to the plasticizer migration from the matrix to the fibers, which increased the matrix Young’s modulus. This migration called matrix deplasticization contributed to the improvement of the overall composite mechanical properties. The true reinforcing effect attributed to the fiber addition and the deplasticizing effect attributed to plasticizer migration were dissociated and quantified. At high fiber content, deplasticizing effect became significant and reduced material processability. This study suggested that the fiber lignin content is susceptible to influence both the water sensitivity and the matrix deplasticization.
•Use of third-generation cephalosporins (3GCs) as definitive treatment for AmpC-producing Enterobacteriaceae is possible.•Initial severity, bacterial species, inoculum size and infection source are ...key parameters to evaluate antibiotic efficacy.•Prospective randomised studies are needed to allow the use of 3GC in infections caused by ESCPM bacteria.
The burden of antibiotic-resistant infections among Gram-negative bacteria is increasing. Resistance to third-generation cephalosporins (3GCs) in Enterobacteriaceae is mainly conferred by the acquisition of β-lactamases or by deregulation of natural genetically-encoded β-lactamase enzymes. Enterobacteriaceae such as Enterobacter spp., Serratia marcescens, Citrobacter freundii, Providencia spp. and Morganella morganii (ESCPM group) possess chromosomally-encoded inducible AmpC β-lactamases. AmpC can be overproduced as a response to β-lactam antibiotic exposure or by constitutive dysfunction of the AmpC regulation system. This overproduction can lead to the inactivation of 3GCs. Based on small clinical studies, international guidelines and expert recommendations suggest that 3GCs should be avoided as definitive therapy for infections caused by ESCPM group organisms. In this narrative review, we discuss the published literature and evaluate the risk related to 3GC use in the case of documented ESCPM infection.
We propose a quantitative approach to probe the spatial heterogeneities of interactions in macromolecular gels, based on a combination of small angle X-ray (SAXS) and neutrons (SANS) scattering. We ...investigate the structure of model gluten protein gels and show that the gels display radically different SAXS and SANS profiles when the solvent is (at least partially) deuterated. The detailed analysis of the SANS signal as a function of the solvent deuteration demonstrates heterogeneities of sample deuteration at different length scales. The progressive exchange between the protons (H) of the proteins and the deuteriums (D) of the solvent is inhomogeneous and 60 nm large zones that are enriched in H are evidenced. In addition, at low protein concentration, in the sol state, solvent deuteration induces a liquid/liquid phase separation. Complementary biochemical and structure analyses show that the denser protein phase is more protonated and specifically enriched in glutenin, the polymeric fraction of gluten proteins. These findings suggest that the presence of H-rich zones in gluten gels would arise from the preferential interaction of glutenin polymers through a tight network of non-exchangeable intermolecular hydrogen bonds.
The behavior of the barrier height of the SiC/SiO 2 interface has been investigated over a wide temperature range, from 173 K to 523 K. These data complement the literature, providing a better ...knowledge of this parameter, which was studied only over a more restricted temperature range, and never before for low temperatures. It is highlighted that the measured samples exhibit a barrier height temperature dependence very near to the theoretical one (≈-0.7 meVK -1 ). Beyond 473 K, the barrier height seems to drop faster for some samples, reaching ≈-1.4 meVK -1 . If this faster decreasing rate is maintained for higher temperatures, it could limit 4H-SiC MOSFETs performances or reliability for high-temperature applications. It is expected that the data provided here will allow for more accurate modeling of the gate current and the charge injection in the oxide layer of power MOSFETs, leading to more reliable predictions of the oxide lifetime for 4H-SiC MOSFETs.
Apteryx is a genus of flightless birds endemic to New Zealand known to lay very large eggs in proportion to body weight. The eggshell of Apteryx is unusually thin and less porous than allometrically ...expected possibly as a compensation for a very long incubation period. Past studies have been carried out on Apteryx australis, a species which once comprised all kiwi with brown plumage, now separated into three distinct species. These species use different habitats and live at different latitudes and altitudes, therefore generating a need to revise our knowledge of the attributes of their eggshells. In this study, we measured the physical characteristics and water conductance on eggshell fragments of these three species and Great‐spotted Kiwi and relate them to the environmental conditions of their respective environments; we also measured the water vapor conductance of Brown Kiwi eggs of late stages of incubation. We found that several trade‐offs exist between incubation behavior, environmental conditions, and eggshell structure. We found differences between species in eggshell water vapor conductance seemingly related to altitude; Brown Kiwi and Rowi generally inhabiting lower altitudes had the highest conductance and Tokoeka, generally living in montane environments, the lowest. This is achieved by an increased eggshell thickness rather than a pore area reduction. Finally, the water vapor conductance late in incubation was 58% higher than infertile unincubated eggs, suggesting a drastic increase in conductance throughout the long incubation period. Using the values previously reported, we calculated the embryonic eggshell thinning to be 32.5% at the equatorial region of the eggshell. We describe several new features, such as triangular mineral particles in the cuticle, reported for the extinct Trigonoolithus amoei, and confirmed the existence of plugged pores. We suggest that these structures provide microbial protection needed by a burrow nesting species with a long incubation period.
Apteryx incubates its eggs for 74 days in a ground burrow. The eggshell structure reveals adaptations to this type of environment, and in relation to the climate, the eggshell has been laid in.
This work deals with the study of thermoset-thermoplastic blend forming an epoxy-amine/poly-etherimide phase separated to assess the dielectric and thermal performances. These materials would be good ...candidates to replace the passivation layer in semiconductors, particularly ones used as switches in power electronic applications. Polyimide and Parylene are usually quoted and studied. Mixtures based on polymers would be a novel candidate that can manage to be an insulator for the system. The modified and non-modified systems where characterized by transmission electron microscopy, scanning electron microscopy, differential scanning calorimetry, thermogravimetric analysis, dynamic mechanical analysis, dielectric analysis and analytical simulation was carried out on dielectric measurements. These complementary techniques were used first to investigate the presence of the phase separation phenomenon and second to quantify the separated nodules size. The effect of this phase separation was examined and showed enhancement in the dielectric values compared to the pure epoxy system. It was finally simulated to show a close assumption of what is found experimentally.
Epoxy – polyetherimide, a homogenous phase separated blend, studied to show the effect of phase separation phenomenon in an organic-organic blend on the thermal, mechanical and electrical properties. The presence of the thermoplastic nodules decreased the permittivity values and the simulation prediction showed similar results with a shift to higher values. Display omitted
The objective of this study was to assess the effectiveness of a catheter-related bloodstream infection (CR BSI) reduction programme and healthcare workers' compliance with recommendations. A 3-year ...surveillance programme of CR BSIs in all hospital settings was implemented. As part of the programme, there was a direct observation of insertion and maintenance of central venous catheters (CVCs) to determine performance. A total of 38 education courses were held over the study period and feedback reports with the results of surveillance and recommendations were delivered to healthcare workers every 6 months. A total of 6722 short-term CVCs were inserted in 4982 patients for 58 763 catheter-days. Improvements of compliance with hand hygiene was verified at the insertion (87·1–100%, P < 0·001) and maintenance (51·1–72·1%, P = 0·029) of CVCs; and the use of chlorhexidine for skin disinfection was implemented at insertion (35·7–65·4%, P < 0·001) and maintenance (33·3–45·9%, P < 0·197) of CVCs. There were 266 CR BSI incidents recorded with an annual incidence density of 5·75/1000 catheter-days in the first year, 4·38 in the second year rate ratio (RR) 0·76, 95% confidence interval (CI) 0·57–1·01 and 3·46 in the third year (RR 0·60, 95% CI 0·44–0·81). The education programme clearly improved compliance with recommendations for CVC handling, and was effective in reducing the burden of CR BSIs.
Aggregation of egg and wheat proteins during cake mixing and baking was monitored by SE-HPLC after sequential extraction of dough and baked cakes in SDS-buffer first and then in SDS/DTE buffer. Three ...cake recipes were compared, including either only egg, only flour, or both flour and egg proteins. Dough mixing did not result in any changes in protein solubility or size distribution. Baking promoted protein aggregation and quickly resulted in the solubility loss of all proteins within the first extracting solvent with the exception of wheat omega gliadins. Upon baking similar kinetics of proteins solubility loss in SDS-buffer were observed regardless of cake recipes. Extraction of the remaining SDS-insoluble proteins with SDS/DTE buffer allowed total protein recovery but only in the case of cakes made on the basis of only flour. For cakes including eggs and despite the presence of DTE a disulfide reducing agent, very large polymers were release into solution, contrarily to the only flour cakes where only small polypeptides (>70,000 g/mol) were mostly recovered. Protein sequential extraction combined with SE-HPLC analysis highlighted the critical role of egg proteins in triggering wheat and egg proteins complexation into SDS-insoluble aggregates stabilized through disulfide but also non-reducible covalent bonds.
•Cake protein aggregation during processing was studied using SE-HPLC.•Dough mixing does not impact the size distribution of egg and flour proteins.•Egg and flour proteins formed mixed aggregates upon baking.•Mixed aggregates are stabilized by thiol/disulfide and iso-peptide bonds.•Eggs proteins contribute to strengthen the cake protein network.
Model gluten gels Banc, A.; Dahesh, M.; Wolf, M. ...
Journal of cereal science,
05/2017, Letnik:
75
Journal Article
Recenzirano
•50/50 gliadin/glutenin blend soluble in ethanol/water as a model of native gluten.•Spontaneous gelation of the model gluten.•Evidence of interactions between gliadin and glutenin in the gel.•Gel ...backbone enriched in glutenin.
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