Cinchona Alkaloid‐Catalyzed Enantioselective Direct Aldol Reaction of N‐Boc‐Oxindoles with Polymeric Ethyl Glyoxylate

The first enantioselective direct aldol addition of N‐Boc‐oxindoles to polymeric ethyl glyoxylate is presented. The reaction is performed by using as low as 0.1 mol% (DHQ)₂PHAL and gives access to α‐hydroxycarboxylate derivatives bearing adjacent secondary alcohol and quaternary stereocenters with high levels of diastereo‐ and enantiocontrol. The use of ethyl glyoxylate in its polymeric form represents an important advantage for synthetic applications and allows us to directly install a C₂ unit ready to be converted in useful building blocks. A further one‐pot protection/deprotection sequence catalyzed by Zn(ClO₄)₂⋅6 H₂O preserved the α‐hydroxycarboxylates from racemization by means of a parasitic alcohol‐catalyzed retroaldol reaction.     

Low-dose eicosapentaenoic or docosahexaenoic acid administration modifies fatty acid composition and does not affect susceptibility to oxidative stress in rat erythrocytes and tissues

In view of the promising future for use of n-3 polyunsaturated fatty acids (PUFA) in the prevention of cancer and cardiovascular diseases, it is necessary to ensure that their consumption does not result in detrimental oxidative effects. The aim of the present work was to test a hypothesis that low doses of eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA) do not induce harmful modifications of oxidative cell metabolism, as modifications of membrane fatty acid composition occur. Wistar rats received by gavage oleic acid, EPA, or DHA (360 mg/kg body weight/day) for a period of 1 or 4 wk. Fatty acid composition and α-tocopherol content were determined for plasma, red blood cell (RBC) membranes, and liver, kidney, lung, and heart microsomal membranes. Susceptibility to oxidative stress induced by tert-butylhydroperoxide was measured in RBC. EPA treatment increased EPA and docosapentaenoic acid (DPA) content in plasma and in all the membranes studied. DHA treatment mainly increased DHA content. Both treatments decreased arachidonic acid content and n-6/n-3 PUFA ratio in the membranes, without modifying the Unsaturation Index. No changes in tissue α-tocopherol content and in RBC susceptibility to oxidative stress were induced by either EPA or DHA treatment. The data suggest that EPA and DHA treatments can substantially modify membrane fatty acids, with-out increasing susceptibility to oxidative stress, when administered at low doses. This opens the possibility for use of low doses of n-3 PUFA for chemoprevention without risk of detrimental secondary effects.     

Distribution of striatin, a newly identified calmodulin-binding protein in the rat brain: an in situ hybridization and immunocytochemical study

The worm-like chain model has often been employed to describe the average conformation of long, intrinsically straight polymer molecules, including DNA. The present study extends the applicability of the worm-like chain model to polymers containing bends or sections of different flexibility. Several cases have been explicitly considered: (i) polymers with a single bend; (ii) polymers with multiple coplanar bends; (iii) polymers with two non-coplanar bends; and (iv) polymers comprised of sections with different persistence lengths. Expressions describing the average conformation of such polymers in terms of the mean-square end-to-end distance have been derived for each case. For cases (i) and (iv), expressions for the projection of the end-to-end vector onto the initial orientation of the chain are presented. The expressions derived here have been used to investigate DNA molecules with sequence-induced bending (A-tracts). Mean-square end-to-end distance values determined from a large number of A-tract containing DNA molecules visualized by scanning force microscopy resulted in an average bend angle of 13.5 degrees per A-tract. A similar study was performed to characterize the flexibility of double-strandedDNA molecules containing a single-stranded region. Analysis of their mean-square end-to-end distance yielded a persistence length of 1.3 nm for single-stranded DNA.     

A novel emergency management platform for smart public safety

This paper proposes an efficient architecture of a smart public safety platform that involves public professional operators as well as citizens. The proposed system is compliant with the emerging paradigm of a smart city. Its main features are that of monitoring, forecasting and managing emergency situations, arising from environmental disasters or crimes. The proposed platform performs a smart and functional integration of heterogeneous components as a smart data gathering and analysis system, a novel professional communication system, wireless sensor networks and social networks. Each element acts not only as an information collector but has autonomous capabilities to cooperate with the others in order to increase the system efficiency and to reduce the need of human interactions. Finally, the paper highlights some open research issues that represent critical aspects and require additional investigations in order to further improve the performance of the proposed platform. Copyright © 2013 John Wiley & Sons, Ltd.     

Numerical and experimental study of guided waves for detection of defects in the rail head

This paper gives insight to the ultrasonic wave propagation in arbitrary cross-section waveguides such as rails, with application to ultrasonic inspection. Due to the geometrical complexity of the rail cross-section, the analytical solution to the wave propagation in the rail is not feasible. A Semi Analytical Finite Element method is described as an alternative yet still robust approach to get the solution of the problem. The free-vibration solution and the forced solution to a laser excitation of the rail head are shown up to a frequency of 500 kHz. The effects of different loading patterns are discussed, and experimental results are provided. The analysis allows for the identification of certain wave modes potentially sensitive to specific types of rail head defects.     

Application-controlled memory management in a single address space environment

With reference to a memory management system supporting the single address space abstraction and a uniform, persistent view of storage, we present a set of mechanisms that allow applications to exert explicit control over memory management activities. These mechanisms make it possible to move the contents of a virtual page to primary memory for fast processor access, or to push these contents back to secondary memory to free primary memory space. Our memory management scheme allows programs to exploit the memory reference pattern of the underlying algorithms, thereby improving utilisation of the system storage resources. This result is illustrated by using significant examples of memory management activities implemented at the application program level. Published online: 8 February 2001     

Nancy Y. Wu (ed.)—Ad Quadratum: The Practical Application of Geometry in Medieval Architecture

No Abstract.  .     

A new portable virus concentrator for use in the field

A new portable apparatus is described which is usable in the field to concentrate large volumes of environmental water for laboratory purposes. The portable virus concentrator consists of four parts: a sampling unit including a programmable peristaltic pump; a 5 μm prefiltration unit; an ultrafiltration system; and a physicochemical measure area. The ultrafiltration system includes 10⁵ NMWL polysulfonate membranes, is performed at the natural pH of water and is followed by an elution step. By this technique, more than 60 l are concentrated in an hour and the recovery of three types of concentrates is observed: parasites are retained in the prefiltrate; bacteria and 80% of viruses are recovered in the concentrates.     

Endocrinological and clinical evaluation of two doses of formestane in advanced breast cancer

Formestane is a selective inhibitor of oestrogen synthesis by aromatase enzymes and induces disease regression in breast cancer patients. This phase II randomised study was carried out to determine whether there were any differences in the effects of two different doses of formestane on oestradiol (E2) serum levels and to evaluate the corresponding clinical activity in post-menopausal patients with positive or unknown oestrogen receptor status pretreated or not for advanced disease. Furthermore, possible drug interference with adrenal steroidogenesis was assessed by measuring 17-hydroxycorticosteroid (17-OHCS) urinary levels. A total of 143 patients entered the study and were randomly assigned to receive formestane 250 mg (72 patients) or formestane 500 mg (71 patients), both given i.m. every 2 weeks. In comparison with baseline, E2 serum levels decreased by an average of 40% after only 15 days and remained unchanged thereafter, with no difference being observed between the two doses. The values of 17-OHCS remained unchanged during treatment in both groups. Objective responses were 28% (19/69) in the 250 mg and 46% (31/68) in the 500 mg group. In conclusion, the two formestane doses were equally effective in reducing E2 levels without affecting adrenal function, and in inducing a considerable percentage of clinical responses.