Vertical transmission and early diagnosis of the microsporidian Enterocytozoon hepatonaei in Whiteleg Shrimp Penaeus vannamei

Microsporidia, which are ubiquitous obligate intracellular parasites responsible for a variety of diseases and economic losses in farming, have different transmission strategies. While horizontal transmission relies on sufûcient parasite numbers released into environment, vertical transmission requires host reproduction to occur leading to a lower virulence, and also induces a sex ratio distortion. The second strategy has been reported in a broad range of hosts from protists to mammals, in which insects and amphipod crustaceans as the most common. The present study shows the first evidence of vertical transmission of a microsporidia in decapod crustaceans via an experimental description of the infection by Enterocytozoon hepatopenaei (EHP) in whiteleg shrimp Penaeus vannamei. The group of healthy shrimp was infected with EHP by feeding with infected-shrimp tissue and sharing habitat. The presence of EHP in the infected shrimps was detected by using Polymerase Chain Reaction (PCR) method with specific primers EHP-510F/EHP-510R and histopathological analysis. The Nauplius, Zoae 1 and Zoae 2 stages collected from the infected female broodstocks demonstrated that EHP can infect offspring from their parental shrimp, and interestingly EHP can be detected from Nauplius stage of shrimp by the use of PCR method

Troubleshooting interactive complexity bugs in wireless sensor networks using data mining techniques

This article presents a tool for uncovering bugs due to interactive complexity in networked sensing applications. Such bugs are not localized to one component that is faulty, but rather result from complex and unexpected interactions between multiple often individually non-faulty components. Moreover, the manifestations of these bugs are often not repeatable, making them particularly hard to find, as the particular sequence of events that invokes the bug may not be easy to reconstruct. Because of the distributed nature of failure scenarios, our tool looks for {\em sequences\/} of events that may be responsible for faulty behavior, as opposed to localized bugs such as a bad pointer in a module. We identified several challenges in applying discriminative sequence mining for root cause analysis when the system fails to perform as expected and presented our solutions to those challenges. We also presented two alternatives schemes, namely, two stage mining and the progressive discriminative sequence mining to address the scalability challenge. An extensible framework is developed where a front-end collects runtime data logs of the system being debugged and an offline back-end uses frequent discriminative pattern mining to uncover likely causes of failure. We provided three case studies where we applied our tool successfully to troubleshoot the cause of the problem. We uncovered a kernel-level race condition bug in the LiteOS operating system and a protocol design bug in the directed diffusion protocol. We also presented a case study of debugging a multichannel MAC protocol that was found to exhibit corner cases of poor performance (worse than single channel MAC). The tool helped uncover event sequences that lead to a highly degraded mode of operation. Fixing the problem significantly improved the performance of the protocol. Finally, we provided a detailed analysis of tool overhead in terms of memory requirements and impact on the running application.unpublishednot peer reviewe

Challenges and strategies towards smart window practical applications

The metal-insulator transition (MIT) property of vanadium dioxide (VO2) appeals to various thermochromic applications including smart windows, IR photodetectors, thermal sensors, and terahertz devices. Nevertheless, there are very few commercialized smart window practical applications to be found. Temperature-dependence of crystalline and band structures is shown by increasing electrical conductivity and decrease intensity transmittance at a phase transition temperature (Tc ~ 68 oC) that leads to peculiar smart optical devices. However, high temperature operation, low luminous transmittance (Tlum), small solar modulation contrast (∆T), and thermodynamically unstable phase in real environments are drawbacks and challenges for practical applications. This chapter presents the thermochromic properties, challenges, and strategies for the future of vanadium dioxide for smart window practical applications

AROMATASE INHIBITORY AND CYTOTOXIC ACTIVITIES OF CHEMICAL CONSTITUENTS FROM THE VIETNAMESE MEDICINAL PLANT BAN-CHI-LIEN (SCUTELLARIA BARBATA D. DON)

Aromatase inhibitory and cytotoxic activities were determined for apigenin, luteolin and the new diterpene named scutebarbalactone VN, which were obtained by bioassay-guided fractionation and isolation from the methanol extract of the Vietnamese medicinal plant Banchi-lien (Scutellaria barbata D. Don). In the aromatase inhibition assay, an IC50 value of 3.36 mM was found for scutebarbalactone VN, while IC50  values of 7.2 mM and 7.95 mM were found for the positive controls aminoglutethimide and b-estradiol, respectively. In the cytotoxicity  assays using a panel of human cancer cell lines, scutebarbalactone VN showed promising anticancer activity with IC50  ranging from 2.15 to 8.3 mM compared with those of the positive control ellipticine ranging from 1.0 to 2.1 mM. Apigenin and luteolin were found to be inactive  in both assays