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Human interactive proofs (HIPs) are a basic security measure on the Internet to avoid automatic attacks. There is an ongoing effort to find a HIP that is secure enough yet easy for humans. Recently, a new HIP has been designed aiming at higher security: the Civil Rights Completely Automated Public Turing test to tell Computers and Humans Apart (CAPTCHA). It employs the empathy capacity of humans to further strengthen Securimage, a well-known text CAPTCHA. In this paper, we analyze it from a security perspective, finding fundamental design flaws. Using several well-known machine learning (ML) algorithms, we analyze to what extent these flaws affect its security. We discover that thanks to them, we can create a successful side-channel attack. This attack is able to correctly solve the HIP on 20.7 % of occasions, much more than enough to consider it broken. Thus, we show that there is no need to solve the problem of optical character recognition nor empathy analysis for computers to break this particular HIP. ML can be successfully used to break a HIP that uses both with a side-channel attack. This security analysis can be applied to other HIPs. It will allow to test whether they are leaking too much information by unexpected ways, given non-evident design flaws. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The pharmaceutical industry is a great consumer of high quality water, which must fulfill severe specifications concerning chemical impurities and endotoxins. In the present work, an industrial installation was built and operation parameters were searched for a high quality water production process by ozone refining treatment. In the design and building of ozonation system, and also in the techniques and procedures for the quality control assurance of the process and the final product, GMP, GLP and up-to-date Pharmacopeia were taken into account. Tap water previously treated to obtain purified water with suitable values of initial conductivity was employed for ozonation. Different ozone concentrations in the gas and in the liquid, liquid flows and the effect of ultraviolet light were assayed. A flow diagram description of the ozonation process is presented. A challenge to the system was conducted in which endotoxins were inoculated into the purified water. The effect of ozonation treatment on endotoxin content was determined. It was shown that, starting with water with good initial conductivity and by an ozonation polishing process it is possible to industrially produce high quality water for pharmaceutical use, which fulfills the international standards. A preliminary analysis showed the economic feasibility of this process compared to another where distillation is employed as a final step. [ABSTRACT FROM AUTHOR]

Ozone efficiency in the water treatment systems is widely published in national and international papers. The criteria design of the treatment plants have changed over the years with increasing knowledge about the mechanism through which ozone reacts with chemical and microbiological pollutants. It recognizes the existence of a relationship between morphological and physiological characteristics of microorganisms and their resistance to ozone. However, there are few studies reported about the mechanisms by which ozone inactivates microorganisms in aqueous media. The aim of this study was to evaluate the effect of ozone on cytoplasmic membrane and enzymes related to oxidative balance on two microorganisms: Escherichia coli ATCC 25922 and Salmonella enterica var. Thyphimurium ATCC 12 048. From a kinetic study was determined, the variation of the efflux of potassium, changes in SH groups and the action exerted by ozone on the enzymes catalase and superoxide dismutase. The results showed an involvement of SH groups present, mainly, in protein and the potassium efflux outside microbial cells, demonstrating that these compound are among the first targets of ozone on microorganisms. An increased activity of the catalase enzyme and a decreased activity of superoxide dismutase enzyme were observed. The decrease in the relationship between these two enzymes suggests that the antioxidant systems of microorganisms are not able to counteract the damage caused by ozone. [ABSTRACT FROM AUTHOR]

Introduction: Ozonized Sunflower Oil (OLEOZON®) is a registered drug developed at the Cuban Ozone Research Center and successfully employed in the treatment of different infection diseases. It is generally accepted, that the antimicrobial activity of ozonized vegetable oils it is related to the action of peroxidic compounds formed during ozonevegetable oil reaction. The main targets of these peroxides on microorganism could be unsaturated lipids and proteins containing sulphydryl groups. Material and Methods: In this work, the polar fraction of OLEOZON® was isolated by a silicagel column chromatography method and the components of polar fraction were isolated by thin layer chromatography (TLC) and molecular exclusion - high performance liquid chromatographic (RP-HPLC). The components of polar fraction were characterized by the combination of nuclear magnetic resonance spectroscopy (NMR) and electro spray mass spectrometry (ESI-MS). S. Aureus ATCC 25923 and P. Aeruginosa ATCC 27853 strains were used to evaluate the in vitro activity (minimal inhibitory and minimal bactericidal concentrations) of OLEOZON® and its polar fraction. The content of potassium ions released to media by bacterial cells was employed as a criterion of alteration of the cell membrane permeability. Also, the total sulphydryl groups and the total protein content were measured. Results and Discussion: In the polar fraction of OLEOZON® are concentrated the oxidant and polar compounds formed. Different results were found for the two studied microorganism related to the different bacterial membrane composition. Conclusion: The main action mechanism of OLEOZON® again S. Aureus and P. Aeruginosa it is related to oxidative attack of peroxidic compounds to microorganism membranes. [ABSTRACT FROM AUTHOR]

This paper presents the ozonization evaluation of a secondary effluent. Parameters of reactor design as the value of the initial demand and the kinetic constant of consumption of ozone were determined. The obtained values were 1,6 mg/L and 0,192 min-1 respectively. As well as, ozone effluent disinfection was evaluated to determine the most appropriate operation conditions, to guarantee a sure disinfection and to diminish the environmental impact. The ozonization effect on the quality effluent parameters was evaluated. They were chemistry oxygen demand, the absorbance value to 254 nm, conductivity, pH, biochemical oxygen demand and total suspended solids total. The ozone disinfection was very effective for the inactivation of total and fecal coliforms with a Ct of 5 mg.min/L. On the other hand, the secondary effluent was inoculated with a concentration of 3,4 x 10² UFC/mL of Pseudomonas aeruginosa, to simulate a potential contamination. This pathogen microorganism is frequent in this wastewater and it is resistant to the chloration. The results indicated that a dose of 7 mg/L during 5 minutes is enough. The ozone reduces the environmental impact as disinfection stage, since the high chlorine doses generate residual concentrations higher than 3 mg/L. Which is not desirable and it constitutes an ecological risk for the population health, that is supplied of the water receiver body. A design of the contact system was proposed. The chlorination tank can be used as ozonization reactor with a minimum of modifications. The investment costs can be reduced. This diminishes the investment cost for construction cost reduction. A bubble reactor with double baffles is proposed. It is composed by two mixing chambers. The countercurrent contact among the phases is guaranteed. In the third chamber ozone is not injected. The double baffles are recommended to avoid the short circuit effect. [ABSTRACT FROM AUTHOR]

Ozonized Sunflower oil (OLEOZON®) is a therapeutical drug developed at the Ozone Research Center (National Center for Scientific Research). It has been national registered for the treatment of skin infections produced by fungi (1999, 2004) and for the treatment of the giardia lamblia infection (2004). OLEOZON® is a product with a high germicidal power, is effective against virus, bacteria, parasites, and fungi. The aims of this work are to present the chromatographic methods employed in OLEOZON® chemical analysis and to show its main results. In this work, different chromatographic methods like: liquid -- liquid extraction, partition column separation, thin layer chromatography, high performance liquid chromatography, gas -- liquid chromatography, and gas chromatography -- mass spectrometry, were employed. Firstly, the OLEOZON® volatile and partially volatile compounds were extracted, identified, and quantified. Hexanaldehyde, nonaldehyde, and 3-nonenaldehyde were the main products present on this OLEOZON® fraction. Also, OLEOZON® was analyzed by partition column chromatography and two fractions were obtained. The triglycerides that have not reacted with ozone were collected in the nom-polar fraction, by the contrary; the ozone-modified triglycerides were collected in the polar fraction. The nom-polar fraction triglycerides were identified by gas -- liquid chromatography and the compounds with lower molecular weights, presents in the same fraction, were identified by gas -- chromatography -- mass spectrometry. The combination of all the chromatographic techniques employed allow to determine the general composition of OLEOZON®, taking into consideration the amount of nom-modified triglycerides, the content of modified triglycerides (oxidized and polymerized triglycerides), and the lineal compounds with a carbon length between six and nine and carbonylic or carboxylic functions on its structure. The analytical methods developed in this work for OLEOZON® characterization have never been previously employed on the analysis of any ozonized vegetable oil. [ABSTRACT FROM AUTHOR]