An Efficient Algorithm in Computing Optimal Data Concentrator Unit Location in IEEE 802.15.4g AMI Networks

With a view to achieve several goals in the smart grid (SG) such as making the production and delivery of electricity more cost-effective as well as providing consumers with available information which assists them in controlling their cost, the advanced metering infrastructure (AMI) system has been playing a major role to realize such goals. The AMI network, as an essential infrastructure, typically creates a two-way communication network between electricity consumers and the electric service provider for collecting of the big data generated from consumer’s smart meters (SM). Specifically, there is a crucial element called a data concentrator unit (DCU) employed to collect the boundless data from smart meters before disseminating to meter data management system (MDMS) in the AMI systems. Hence, the location of DCU has significantly impacted the quality of service (QoS) of AMI network, in particular the average throughput and delay. This work aims at developing an efficient algorithm in determining the minimum number of DCUs and computing their optimum locations in which smart meters can communicate through good quality wireless links in the AMI network by employing the IEEE 802.15.4g with unslotted CSMA/CA channel access mechanism. Firstly, the optimization algorithm computes the DCU location based on a minimum hop count metric. Nevertheless, it is possible that multiple positions achieving the minimum hop count may be found; therefore, the additional performance metric, i.e. the average throughput and delay, will be utilized to select the ultimately optimal location. In this paper, the maximum throughput with the acceptable averaged delay constraint is proposed by considering the behavior of the AMI meters, which is almost stationary in the AMI network. In our experiment, the algorithm is demonstrated in different scenarios with different densities of SM, including urban, suburban, and rural areas. The simulation results illustrate that the smart meter density and the environment have substantially impacted on a decision for DCU location, and the proposed methodology is significantly effective. Furthermore, the QoS in urban area, i.e. a highly populated area for SM, of the AMI network is better than those in the suburban and rural areas, where the SM density is quite sparse, because multiple available hops and routes created by neighboring meters in the dense area can help improve the average throughput and delay with the minimum hop count

GC-MS profiling, anti-oxidant and anti-diabetic assessments of extracts from microalgae Scenedesmus falcatus (KU.B1) and Chlorella sorokiniana (KU.B2)

Microalgae are a potentially valuable source in the food, pharmaceutical and nutraceutical sectors. While biological activities surveys have investigated the pharmaceutical properties of a few microalgae species, there are not many reports covering biological activity studies. This study was carried out to identify the metabolites by gas chromatography-mass spectrometry and evaluate the anti-oxidant, anti-diabetic properties of green algae extracts, Chlorella sorokiniana (KU.B2) and Scenedesmus falcatus (KU.B1). A total of 51 different chemical constituents were detected and tentatively identified. The primary compounds in both microalgae extracts included (R)-2-hexanol (38.67% in C. sorokiniana and 23.53% in S. falcatus), n-hexadecanoic acid (13.58% in C. sorokiniana and 18.94% in S. falcatus) and octadecanoic acid (22.30% in C. sorokiniana and 32.67% in S. falcatus). According to the profiling results, the C. sorokiniana extract exhibited greater anti-oxidant activity, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging (IC50 = 480.30 ±?14.85 µg ml-1), nitric oxide (NO) radical scavenging (562.73 ±?3.52 µg mL-1) and ferric reducing anti-oxidant power (FRAP) of 58.51 ± 2.42 mgTE g-1. Comparatively, the C. sorokiniana extract had higher contents of alpha-glucosidase and alpha-amylase (IC50 = 491.22 ± 78.41 and 2,817.00 ±143.04 µg mL-1, respectively) than the S. falcatus extract. This first report demonstrated anti-diabetic effect of both extracts on diabetic enzymes. The results confirm microalgae's anti-oxidant and anti-diabetic properties and suggest their potential benefits in cosmeceutical, nutraceutical and pharmaceutical applications

Trade patterns facilitating highly pathogenic avian influenza virus dissemination in the free-grazing layer duck system in Vietnam

Highly pathogenic avian influenza (HPAI) viruses continue to threaten smallholder poultry producers in several South‐east Asian countries, including Vietnam. In particular, the free‐grazing duck system has been repeatedly highlighted as a major risk factor for HPAI outbreaks. Free‐grazing ducks, which scavenge on rice paddies after the harvest, account for a large proportion of the duck population in Vietnam and the wider South‐east Asian region. However, the structure and dynamics of the free‐grazing duck production from farm to consumption has not been described for Vietnam. In this study, we used a value chain approach to provide a complete picture of the actors involved in the production and marketing of free‐grazing duck eggs and spent layer ducks, as well as to investigate the governance structure of this food system. Group interviews and key informant interviews were conducted in two provinces located in the Mekong River Delta (MRD) and the Red River Delta (RRD). The results presented here highlight similarities and differences in farming and trade practices between the two provinces. The trade of spent layer ducks involved large volumes of live ducks being sent to China and Cambodia for consumption, generating a substantial risk of transboundary spread of pathogens, including HPAI viruses. We describe the major role of “duck yards”, which act as hubs in the northbound trade of spent layer ducks. These yards should be considered as essential links in the value chain of spent layer ducks when considering HPAI surveillance and control. The veterinary authorities are only marginally involved in the value chain activities, and their influence could be strengthened by increasing surveillance activities for instance in duck yards. Last, we discuss the dynamics of the duck value chain and further implications for future HPAI management policies

Age-Related Differences in Levels of Blood Chemistry Parameters and Cardiac Marker Proteins in Commercial Broilers

ABSTRACT The effect of age on levels of blood biochemical parameters in broiler chickens is largely unknown. The purpose of the present study was to investigate physiological alterations of blood chemistry variables in renal, liver, lipid and cardiac profile in commercial broilers at the age of 2(n=20) and 7 weeks (n=40). The results showed that compared with broiler chicks at the age of 7 weeks, those at the age of 2 weeks had significantly higher levels of blood urea nitrogen, creatinine, uric acid, triglycerides and the enzymes alanine aminotransferase and alkaline phosphatase. Older chicks, on the other hand, displayed significantly higher levels of total protein, albumin, total cholesterol and the enzyme gammaglutamyl transferase. Although a significantly higher activity of cardiac enzyme aspartate aminotransferase and a significantly lower activity of lactate dehydrogenase were observed in older chickens, younger broilers exhibited a significantly higher concentration of the cardiac-specific marker troponin T. There was no significant age-related difference either in the levels of cardiac enzymes creatine kinase, creatine kinase MB or in glucose level. Cardiac troponin T concentration correlated significantly with that of CK-MB in both groups of animals studied. These results underline the importance of age as a significant contributor of variation in levels of several blood chemistry parameters and cardiac marker proteins, especially cardiac troponin T in broiler chicks

Role of Terrestrial Wild Birds in Ecology of Influenza A Virus (H5N1)

Recent viruses are pathogenic for some small terrestrial bird species

Avian Influenza (H5N1) Susceptibility and Receptors in Dogs

Inoculation of influenza (H5N1) into beagles resulted in virus excretion and rapid seroconversion with no disease. Binding studies that used labeled influenza (H5N1) showed virus attachment to higher and lower respiratory tract tissues. Thus, dogs that are subclinically infected with influenza (H5N1) may contribute to virus spread

Influenza Virus A (H1N1) in Giant Anteaters (Myrmecophaga tridactyla)

In February 2007, an outbreak of respiratory disease occurred in a group of giant anteaters (Myrmecophaga tridactyla) at the Nashville Zoo. Isolates from 2 affected animals were identified in March 2007 as a type A influenza virus related to human influenza subtype H1N1