► Yogurt manufactured with increased levels of oligofructose. ► Weak gel, showing thixotropy and pseudoplastic behavior was observed. ► Survival analysis methodology indicated addition of 2.58% ...wt.v−1 of oligofructose.
The addition of prebiotics such as oligofructose to yogurt can result in a product with consumer benefits, since they stimulate growth of benefic bacteria present in the intestine and also provide a low calorie product, since one can add less sugar to the formulation due to their sweetening power. This work aimed to evaluate the effect of increasing concentrations of oligofructose addition on physicochemical, rheological and microbiological characteristics of non-flavored yogurt. Furthermore, it was investigated the reaction of consumers with the use of the survival analysis methodology. The addition of oligofructose showed no influence on the pH, proteolysis or the viability of Streptococcus thermophilus or Lactobacillus bulgaricus during 28days of refrigerated storage (p>0.05). According to rheological measurements the yogurt supplemented with oligofructose was characterized as a weak gel, showing thixotropic and pseudoplastic behavior. Survival analysis was used to investigate consumer responses with respect to different levels of supplementation of plain yogurt with oligofructose (0%, 2%, 4%, 6% and 8% wt.v−1). Using the survival analysis and considering a rejection by 25% of the consumers, the level of oligofructose that can be added to the yogurt was shown to be 2.58% wt.v−1.
Human mobility is an important driver of geographic spread of infectious pathogens. Detailed information about human movements during outbreaks are, however, difficult to obtain and may not be ...available during future epidemics. The Ebola virus disease (EVD) outbreak in West Africa between 2014-16 demonstrated how quickly pathogens can spread to large urban centers following one cross-species transmission event. Here we describe a flexible transmission model to test the utility of generalised human movement models in estimating EVD cases and spatial spread over the course of the outbreak. A transmission model that includes a general model of human mobility significantly improves prediction of EVD's incidence compared to models without this component. Human movement plays an important role not only to ignite the epidemic in locations previously disease free, but over the course of the entire epidemic. We also demonstrate important differences between countries in population mixing and the improved prediction attributable to movement metrics. Given their relative rareness, locally derived mobility data are unlikely to exist in advance of future epidemics or pandemics. Our findings show that transmission patterns derived from general human movement models can improve forecasts of spatio-temporal transmission patterns in places where local mobility data is unavailable.
Transmission of Zika virus (ZIKV) in the Americas was first confirmed in May 2015 in northeast Brazil. Brazil has had the highest number of reported ZIKV cases worldwide (more than 200,000 by 24 ...December 2016) and the most cases associated with microcephaly and other birth defects (2,366 confirmed by 31 December 2016). Since the initial detection of ZIKV in Brazil, more than 45 countries in the Americas have reported local ZIKV transmission, with 24 of these reporting severe ZIKV-associated disease. However, the origin and epidemic history of ZIKV in Brazil and the Americas remain poorly understood, despite the value of this information for interpreting observed trends in reported microcephaly. Here we address this issue by generating 54 complete or partial ZIKV genomes, mostly from Brazil, and reporting data generated by a mobile genomics laboratory that travelled across northeast Brazil in 2016. One sequence represents the earliest confirmed ZIKV infection in Brazil. Analyses of viral genomes with ecological and epidemiological data yield an estimate that ZIKV was present in northeast Brazil by February 2014 and is likely to have disseminated from there, nationally and internationally, before the first detection of ZIKV in the Americas. Estimated dates for the international spread of ZIKV from Brazil indicate the duration of pre-detection cryptic transmission in recipient regions. The role of northeast Brazil in the establishment of ZIKV in the Americas is further supported by geographic analysis of ZIKV transmission potential and by estimates of the basic reproduction number of the virus.
This work investigated the effect of the addition of different antioxidants (ascorbic acid, glucose oxidase, cysteine, and jabuticaba extract) on the rheological and sensorial properties of the ...probiotic petit suisse cheese. Absence of influence of the antioxidants at the physico-chemical characteristics of the petit suisse cheese was observed. Overall, the petit suisse cheeses presented weak gel characteristics and behaved as pseudoplastic material, except for control. All treatments exhibited a thixotropic non-Newtonian behavior; however, higher hysteresis area was obtained for control sample, which indicates that antioxidants incorporated to petit suisse had a protective effect on the typical thixotropic behavior of the Quark gel. The commercial sample presented higher scores for all aspects by consumers, whereas the probiotic petit suisse samples presented opposite behavior. Projective mapping was able to generate a vocabulary where the sample containing jabuticaba skin extract obtained by supercritical extraction was characterized by the panelists as presenting grape flavor and purple color.
Aim
This study aimed to experimentally validate a computational fluid dynamics (CFD) model, using micro‐particle image velocimetry (micro‐PIV) measurements of the irrigation flow velocity field ...developed in confluent canals during irrigation with a side‐vented needle.
Methodology
A microchip with confluent canals, manufactured in polydimethylsiloxane was used in a micro‐PIV analysis of the irrigation flow using a side‐vented needle placed 3 mm from the end of the confluence of the canals. Velocity fields and profiles were recorded for flow rates of 0.017 and 0.1 ml/s and compared with those predicted in CFD numerical simulations (using a finite volume commercial code – FLUENT) for both laminar and turbulent regimes.
Results
The overall flow pattern, isovelocity and vector maps as well as velocity profiles showed a close agreement between the micro‐PIV experimental and CFD predicted data. No relevant differences were observed between the results obtained with the laminar and turbulent flow models used.
Conclusions
Results showed that the laminar CFD modelling is reliable to predict the flow in similar domains.
Exposure to oxygen may induce a lack of functionality of probiotic dairy foods because the anaerobic metabolism of probiotic bacteria compromises during storage the maintenance of their viability to ...provide benefits to consumer health. Glucose oxidase can constitute a potential alternative to increase the survival of probiotic bacteria in yogurt because it consumes the oxygen permeating to the inside of the pot during storage, thus making it possible to avoid the use of chemical additives. This research aimed to optimize the processing of probiotic yogurt supplemented with glucose oxidase using response surface methodology and to determine the levels of glucose and glucose oxidase that minimize the concentration of dissolved oxygen and maximize the Bifidobacterium longum count by the desirability function. Response surface methodology mathematical models adequately described the process, with adjusted determination coefficients of 83% for the oxygen and 94% for the B. longum. Linear and quadratic effects of the glucose oxidase were reported for the oxygen model, whereas for the B. longum count model an influence of the glucose oxidase at the linear level was observed followed by the quadratic influence of glucose and quadratic effect of glucose oxidase. The desirability function indicated that 62.32ppm of glucose oxidase and 4.35ppm of glucose was the best combination of these components for optimization of probiotic yogurt processing. An additional validation experiment was performed and results showed acceptable error between the predicted and experimental results.
This research evaluated the action of jabuticaba skin extract (JSE) obtained through supercritical extraction compared with the antioxidants ascorbic acid, cysteine chloride, and glucose oxidase ...along probiotic Petit Suisse cheese processing. Physico-chemical analyses (pH, proteolysis, antioxidant activity, organic acids, and fatty acid profile) and microbiological (starter culture and probiotic culture counts) were carried out over 28days of refrigerated storage. Addition of JSE on Petit Suisse was variable and dependent of the evaluated parameters with satisfactory findings in consumer test. However, the supplementation of probiotic Petit Suisse with JSE should be evaluated with care.
•Jabuticaba skin extract added during the probiotic Petit Suisse processing•Increased antioxidant activity, organic acids content α-linolenic acid values and postacidification•No effect in Bifidobacterium lactis counts and minor decrease in Lactobacillus acidophilus counts•Satisfactory performance in consumer test
Summary The supraclavicular island flap has been widely used in head and neck reconstruction, providing an alternative to the traditional techniques like regional or free flaps, mainly because of its ...thin skin island tissue and reliable vascularity. Head and neck patients who require large reconstructions usually present poor clinical and healing conditions. An early experience using this flap for late-stage head and neck tumour treatment is reported. Forty-seven supraclavicular artery flaps were used to treat head and neck oncologic defects after cutaneous, intraoral and pharyngeal tumour resections. Dissection time, complications, donor and reconstructed area outcomes were assessed. The mean time for harvesting the flaps was 50 min by the senior author. All donor sites were closed primarily. Three cases of laryngopharyngectomy reconstruction developed a small controlled (salivary) leak that was resolved with conservative measures. Small or no strictures were detected on radiologic swallowing examinations and all patients regained normal swallowing function. Five patients developed donor site dehiscence. These wounds were treated with regular dressing until healing was complete. There were four distal flap necroses in this series. These necroses were debrided and closed primarily. The supraclavicular flap is pliable for head and neck oncologic reconstruction in late-stage patients. High-risk patients and modified radical neck dissection are not contraindications for its use. The absence of the need to isolate the pedicle offers quick and reliable harvesting. The arc of rotation on the base of the neck provides adequate length for pharyngeal, oral lining and to reconstruct the middle and superior third of the face.
Controlled surface functionalization is demonstrated by nitric acid hydrothermal oxidation on multiwall carbon nanotubes (MWCNTs). The formation and evolution of oxygen functional groups were ...systematically investigated as a function of the HNO3 concentration on MWCNTs with different structural and morphological characteristics, employing temperature-programmed desorption coupled with mass spectrometry, thermogravimetry and differential scanning calorimetry, Raman spectroscopy and N2 porosimetry analysis. Hydrothermal treatment provides controlled MWCNT modification by specific oxygen functionalities at amounts determined by the morphology, texture and crystallinity of the pristine materials. Hydrothermal oxidation competes well with the harsh boiling nitric acid treatment regarding the total amount of oxygen functionalities, while requiring much lower amounts of oxidizing agent and, most importantly, reducing amorphous carbon deposits on the MWCNT surface, a major drawback of aggressive liquid phase oxidation methods. Detailed pore structure analysis revealed a progressive increase of the surface area upon hydrothermal functionalization, whereas the mesopore structure varied consistently with the intrinsic MWCNT properties related to the packing of the nanotube bundles and the reduction of amorphous carbon. These advantageous features render nitric acid hydrothermal oxidation an efficient functionalization process to fine tune and optimize the surface chemistry of MWCNTs for target applications, circumventing the need for additional purification post-processing.
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