An Experimental Study of Diversity with Off-The-Shelf AntiVirus Engines

Fault tolerance in the form of diverse redundancy is well known to improve the detection rates for both malicious and non-malicious failures. What is of interest to designers of security protection systems are the actual gains in detection rates that they may give. In this paper we provide exploratory analysis of the potential gains in detection capability from using diverse AntiVirus products for the detection of self-propagating malware. The analysis is based on 1599 malware samples collected by the operation of a distributed honeypot deployment over a period of 178 days. We sent these samples to the signature engines of 32 different AntiVirus products taking advantage of the VirusTotal service. The resulting dataset allowed us to perform analysis of the effects of diversity on the detection capability of these components as well as how their detection capability evolves in time

Hydroxyurea derivatives of irofulven with improved antitumor efficacy.

Irofulven is a semi-synthetic derivative of Illudin S, a toxic sesquiterpene isolated from the mushroom Omphalotus illudens. Irofulven has displayed significant antitumor activity in various clinical trials but displayed a limited therapeutic index. A new derivative of irofulven was prepared by reacting hydroxyurea with irofulven under acidic conditions. Acetylation of this new compound with acetic anhydride produced a second derivative. Both of these new derivatives displayed significant antitumor activity in vitro and in vivo comparable to or exceeding that of irofulven

Effect of Long-Term Zinc Pollution on Soil Microbial Community Resistance to Repeated Contamination

The aim of the study was to compare the effects of stress (contamination trials) on the microorganisms in zinc-polluted soil (5,018 mg Zn kg−1 soil dry weight) and unpolluted soil (141 mg Zn kg−1 soil dw), measured as soil respiration rate. In the laboratory, soils were subjected to copper contamination (0, 500, 1,500 and 4,500 mg kg−1 soil dw), and then a bactericide (oxytetracycline) combined with a fungicide (captan) along with glucose (10 mg g−1 soil dw each) were added. There was a highly significant effect of soil type, copper treatment and oxytetracycline/captan treatment. The initial respiration rate of chronically zinc-polluted soil was higher than that of unpolluted soil, but in the copper treatment it showed a greater decline. Microorganisms in copper-treated soil were more susceptible to oxytetracycline/captan contamination. After the successive soil contamination trials the decline of soil respiration was greater in zinc-polluted soil than in unpolluted soil

Prion protein interaction with soil humic substances: environmental implications

Transmissible spongiform encephalopathies (TSE) are fatal neurodegenerative disorders caused by prions. Animal TSE include scrapie in sheep and goats, and chronic wasting disease (CWD) in cervids. Effective management of scrapie in many parts of the world, and of CWD in North American deer population is complicated by the persistence of prions in the environment. After shedding from diseased animals, prions persist in soil, withstanding biotic and abiotic degradation. As soil is a complex, multi-component system of both mineral and organic components, it is important to understand which soil compounds may interact with prions and thus contribute to disease transmission. Several studies have investigated the role of different soil minerals in prion adsorption and infectivity; we focused our attention on the interaction of soil organic components, the humic substances (HS), with recombinant prion protein (recPrP) material. We evaluated the kinetics of recPrP adsorption, providing a structural and biochemical characterization of chemical adducts using different experimental approaches. Here we show that HS act as potent anti-prion agents in prion infected neuronal cells and in the amyloid seeding assays: HS adsorb both recPrP and prions, thus sequestering them from the prion replication process. We interpreted our findings as highly relevant from an environmental point of view, as the adsorption of prions in HS may affect their availability and consequently hinder the environmental transmission of prion diseases in ruminants

Selenium Toxicity to Honey Bee (Apis mellifera L.) Pollinators: Effects on Behaviors and Survival

We know very little about how soil-borne pollutants such as selenium (Se) can impact pollinators, even though Se has contaminated soils and plants in areas where insect pollination can be critical to the functioning of both agricultural and natural ecosystems. Se can be biotransferred throughout the food web, but few studies have examined its effects on the insects that feed on Se-accumulating plants, particularly pollinators. In laboratory bioassays, we used proboscis extension reflex (PER) and taste perception to determine if the presence of Se affected the gustatory response of honey bee (Apis mellifera L., Hymenoptera: Apidae) foragers. Antennae and proboscises were stimulated with both organic (selenomethionine) and inorganic (selenate) forms of Se that commonly occur in Se-accumulating plants. Methionine was also tested. Each compound was dissolved in 1 M sucrose at 5 concentrations, with sucrose alone as a control. Antennal stimulation with selenomethionine and methionine reduced PER at higher concentrations. Selenate did not reduce gustatory behaviors. Two hours after being fed the treatments, bees were tested for sucrose response threshold. Bees fed selenate responded less to sucrose stimulation. Mortality was higher in bees chronically dosed with selenate compared with a single dose. Selenomethionine did not increase mortality except at the highest concentration. Methionine did not significantly impact survival. Our study has shown that bees fed selenate were less responsive to sucrose, which may lead to a reduction in incoming floral resources needed to support coworkers and larvae in the field. If honey bees forage on nectar containing Se (particularly selenate), reductions in population numbers may occur due to direct toxicity. Given that honey bees are willing to consume food resources containing Se and may not avoid Se compounds in the plant tissues on which they are foraging, they may suffer similar adverse effects as seen in other insect guilds

Fanghi" in agricoltura, risorsa troppo spesso dimenticata

Solamente pochi agricoltori potrebbero essere a conoscenza del significato del termine perugino, de\la sua origine e del rispetto con cui, ancor oggi, \uece persone anziane di Lucca e provincia ne fanno memoria. ll termine perugino designa il contenuto del pozzo nero ed \ue8 stato coniato secoli fa per indicare l'attivit\ue0 di una cooperativa di imprenditori originari di Perugia periodicamente impegnata a svuotare i pozzineri di tutta la citt\ue0. Tale attivit\ue0 prevedeva il solo e r\uecconosciuto compenso da parte degli agricoltori che ne richiedevano f impiego come concime, usato del resto per fer\ufabzzare i campi fin dall'origine della storia dell'uomo. In Italia forse l'esempio di utilizz azione megl io or ganizzata dei pozzineri si \ue8 avuta nelle marcite, vere e proprie opere di ingegneria idraulica della bassa milanese. Molti ricorderanno che ancora nella seconda met\ue0 del secolo scorso le fogne venivano scaricate nelle campagne e andavano a lambire Ie superfici del terreno, sistemate in modo da agevolare un loro lento scorrimento e l'assorbimento di ci\uf2 che convogliavano. Da Melegnano in gi\uf9 la gente si lamentava bofonchiando che "A MiI\ue0n gh'en i c\ue8ss, a Melegn\ue0n i ud\uf9r" (a Milano ci sono i cessi, a Melegnano gli odori), ma gli effetti mirabili di tale pratica erano pi\uf9 che evidenti: il fieno che si raccoglieva nella pianura padana era costituito da d ue o tre tagli (maggengo,agostano e quando andava bene anche un rachitico terzuolo), mentre in tutta la bassa milanese e nell'attuale provincia di Lodi se ne contavano sette o otto o anche di pi\uf9, fino a undici o dodici, e di ottima qualita'. L'articolo esamina questi aspetti