Rich bioactive phenolic extract production by microbial biotransformation of Brazilian Citrus residues

Flavanones in Citrus are molecules that play an important role in antioxidant activities in nutraceutical products. Recent studies indicate that molecules of the simplest classes of phenolics have higher biological activity and absorption capacity. However, the molecules that have been shown to be very important bioactive compounds of Citrus, such as hesperetin, naringenin and ellagic acid, are found in trace concentrations in the fruit. An interesting environmentally friendly alternative that deserves attention regarding phenolic compound obtaining is the biotransformation of these molecules. The aim of this study was to develop a process of biotransformation of phenolics from Brazilian Citrus residues by solid-state fermentation with the microorganism Paecilomyces variotii. The optimized fermentation conditions were 10 g of Citrus residues (2.0 mm of substrate particle size), 20 mL distilled water, at 32 °C after 48 h of incubation. The development of this process has generated, simultaneously, an increase of 900, 1400 and 1330% of hesperetin, naringenin and ellagic acid concentration, respectively, and an increase of 73% of the antioxidant capacity. These results give strong evidence that microbial biotransformation does not only produce phenolic compounds but also compounds with high biological activity, such as hesperetin and naringenin.     

Environmental impact of poultry production systems on surface water: monitoring the Taquari-Antas basin,southern Brazil

ABSTRACT

The research evaluated the impact of poultry farming on the quality of surface waters in a mountainous area of southern Brazil, in order to collect data and assist in the decision-making for sustainable development. The study monitored 13 spots for two years in the sub-basins with intense poultry activity. The water samples were submitted to physicochemical and microbiological analyses in order to assess the Water Quality Index (WQI). The data were analysed by principal component analysis and Pearson’s correlation. Some zones are able to receive future investments and could serve as a basis for the installation of new agricultural units. Others require greater attention from the environmental control agencies.     

Method for studying the effects of thermal deformations on optical systems for space application

In this paper, the results of the thermo-elastic analysis performed on the stereo channel of the imaging system Integrated Observatory System for the BepiColombo European Space Agency mission to Mercury are presented. The aim of the work is to determine the effects of ambient parameter variations on the equipment performance; the optical performance is changing during the mission lifetime primarily because of the optics misalignments and deformations induced by temperature variations. The camera optics and their mountings are modeled and processed by a thermo-mechanical finite element model (FEM) program, which reproduces the expected optics and structure thermo-elastic deformations in the instrument foreseen operative temperature range, i.e., between -20 °C and 30 °C. The FEM outputs are elaborated using a MATLAB optimization routine: an algorithm based on nonlinear least square data fitting is adopted to determine the surface equation (plane, spherical, nth polynomial) which best fits the deformed optical surfaces. The obtained surfaces are then directly imported into a ZEMAX code for sequential ray-tracing analysis. Variations of the optical spot diagrams, modulation transfer function curves, and ensquared energy are then computed. The overall analysis shows that the preferred solution for mounting the optical elements is adopting the kinematic constraints instead of using the classical glue solution.     

交通环境犯罪：来自瑞典斯德哥尔摩和巴西圣保罗地铁系统的经验总结

通过评估瑞典斯德哥尔摩和巴西圣保罗地铁系统的犯罪活动及扰乱公共秩序行为案例,探讨相关经验教训。对比2个国家地铁系统的时空犯罪模式及上述案例的研究结果,总结环境对犯罪活动及扰乱公共秩序行为的影响。研究中地理信息系统、田野调查和建模等分析过程应用了相应地铁运营商的基础数据。研究发现市中心地铁站及终点站往往比其他站点更容易发生犯罪。除了区位因素,地铁站的环境属性、周边环境及社区环境也会影响站点的犯罪机会。预防犯罪的干预措施必须针对具体犯罪活动、核心地铁站的拥挤情况,特别是易发生犯罪的高峰时段制定。以此总结今后相关研究方向,并提出相应政策建议。     

As (V) biosorption in an aqueous solution using chemically treated lemon (Citrus aurantifolia Swingle) residues

The use of biosorbents to remove metals and metalloids from contaminated water systems has gained great usage in various parts of the world. The objective of the current study was to test lemon peels as biosorbents for As (V). Lemon peels were chemically characterized and arsenic contact experiments were performed to determine the adsorption capacity of the peels using different empirical models. The model that fit the experimental data was the Lagergren empirical model with a correlation coefficient of R= 0.8841. The results show that lemon peels were able to retain 474.8 μg of As (V)/g of biosorbent. PRACTICAL APPLICATION: Lemon agro-industrial waste can be useful in the removal of heavy metals, such as arsenic, from aqueous media.     

Serious games for basic learning mechanisms: reinforcing Mexican children’s gross motor skills and attention

Personal and Ubiquitous Computing - Early childhood is the most important and rapid period of development in a human life as it is a period where the maturation of the brain and the central nervous...     

DDoS protection with stateful software‐defined networking

Distributed denial of service (DDoS) attacks represent one of the most critical security challenges facing network operators. Software‐defined networking (SDN) permits fast reactions to such threats by dynamically enforcing simple forwarding/blocking rules as countermeasures. However, the centralization of the control plane requires that the SDN controller, besides network management operations, should also collect information to identify and mitigate the security menaces. A major drawback of this approach is that it may overload the controller and the control channel. On the other hand, stateful SDN represents a new concept, developed to improve reactivity and offload the controller by delegating local treatments to the switches. In this article, we embrace this paradigm to protect end‐hosts from DDoS attacks. We propose StateSec, a novel approach based on in‐switch processing capabilities to detect and mitigate flooding threats. StateSec monitors packets matching configurable traffic features without resorting to the controller. By feeding an entropy‐based detection algorithm with such monitoring features, it detects and mitigates several threats such as (D)DoS with high accuracy. We implemented StateSec in an SDN platform comparing it with state‐of‐the‐art approaches. We show that StateSec is far more efficient: It achieves very accurate detection levels, reducing at the same time the control plane overhead. We have also evaluated the memory footprint of StateSec for a possible use in production. Finally, we deployed StateSec over a real network to tune its parameters and assess its suitability to real‐world deployments.     

Eucaloric Ketogenic Diet Reduces Hypoglycemia and Inflammation in Mice with Endotoxemia

Dietary strategies to alter the immune response to acute inflammation have the potential to improve outcomes in critically ill patients. A eucaloric ketogenic diet (EKD), composed predominantly of fat with very small amounts of carbohydrate, can provide adequate caloric support while minimizing spikes in blood glucose and reducing oxidative stress. The purpose of this study was to evaluate the effects of an EKD on glycemic control and the inflammatory response after acute endotoxemia in mice. Mice received either an EKD or a carbohydrate‐based control diet (CD) for 4 weeks. Animals subsequently underwent either a 2‐h fast (postprandial) or an overnight fast (postabsorptive), and half of the animals in each diet group were randomized to receive either intraperitoneal lipopolysaccharide (1 mg/kg) or an equivalent volume of saline. Glycemic response, insulin resistance, inflammatory cytokine levels, and the expression of key inflammatory and metabolic genes were measured. After endotoxin challenge, hypoglycemia was more frequent in mice fed a CD than an EKD in the postprandial period. This was due in part to the preservation of hepatic glycogen stores despite endotoxin exposure and prolonged fasting in mice fed an EKD. Furthermore, mice fed the CD had higher levels of IL‐6 and TNF‐α in the postabsorptive period, with a fivefold higher expression of hepatic NFκB compared to mice fed the EKD in both fasting periods. These results suggest that the unique metabolic state induced by an EKD can alter the response to acute inflammation in mice.     

Increasing the robustness of fault identification in rotor dynamics by means of M-estimators

One of the most common problems in rotor dynamics is the identification of faults and model-based methods are often used for this purpose. In some applications, the least-squares (LS) estimate is used to find out the position and the severity of impending faults on the basis of experimental vibration data of rotating machinery. Anyhow LS are not very robust with respect to possible outliers (noise and gross errors) in the experimental data and to inaccuracies in the model.The introduction of weights in the LS algorithm has proven to be effective in increasing the robustness and successful experimental cases, both on test rigs and on real machines, are reported in literature. However, the arbitrary choice of the weights is normally based on operators’ experience. In this paper, an improvement is presented by introducing a method that is robust in itself, the M-estimate, which allows defining automatically the weights. This method is general and can be applied in every problem of regression or estimation, not necessarily related to rotor dynamics.The fundamental theoretical aspects are introduced in the first part, while several experimental test cases are presented by means of fault identification on a test rig and on a gas turbo generator in the second part of the paper. The obtained results highlight the increasing of the accuracy allowed by M-estimate.