The propargylic route as a short and versatile entry to optically active monofluorinated compounds

Using selected models and appropriate NMR techniques, it has been demonstrated that dehydroxyfluorination in the propargylic position can be highly regio- and stereoselective. The corresponding propargylic fluorides are very useful intermediates for short preparations of stereodefined unsaturated or polyunsaturated compounds with a single fluorine atom in allylic or propargylic position. This strategy offers good means for the synthesis of chiral, nonracemic monofluorinated analogues of natural products.     

Adolescent psychosocial risk factors for severe intimate partner violence in young adulthood.

The authors examined prospective measures of psychosocial risk factors as predictors of severe intimate partner violence among a community sample of 610 young adults at risk for intergenerational transmission of depression. The hypothesized risk factors were youth history of depression by age 15 and maternal history of depression. Youth social functioning at age 15 was tested as a mediator of these associations. Results showed that youth history of depression by age 15 predicted victimization at age 20. Severe violence perpetration was predicted by maternal depressive history among women but not men. Youth social functioning was a partial mediator of both associations. In sum, the findings suggest that psychosocial factors observed in adolescence may contribute to the risk of experiencing severe intimate partner violence during young adulthood. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Optimal operation and hydro storage sizing of a wind–hydro power plant

Ambitious targets for renewable power production have been defined for the electric power systems in Europe. The accomplishment of these targets requires the increase in renewable energy production, namely from wind power generation. However, the intermittent nature of wind creates several problems to the power system operation and new approaches based on the combined use of wind power and energy storage technologies need to be developed. In this paper, the concept of the combined use of wind power production and hydro storage/production is exploited, through the development of an operational optimisation approach applied to a wind generator park with little water storage ability. The optimisation model defines the operational strategy to be followed for the hours ahead by a pump station and an hydraulic generator embedded in a wind/hydro pumping facility, using the Portuguese energy remuneration rules. The proposed methodology leads to considerable yearly profits for the wind generator production.     

Correlation between the oxidation mechanism of titanium under a pure oxygen atmosphere,morphology of the oxide scale,and diffusional phenomena

The oxidation behavior of titanium was studied over the temperature range of 600 to 800°C in a pure oxygen atmosphere. A parabolic kinetics period is made up of a succession of short parts whose weight gain is nearly constant and whose beginning is characterized by an alteration of the oxidation rate. The kinetics curve is closely correlated with the morphology of the oxide scale which contains several layers separated by short cracks. These cracks decrease the diffusional flows of oxygen and titanium and alter the oxidation rate. A parabolic-linear kinetics transition is attributed to the formation of a continuous crack between the oxide scale and the matrix. The oxide scale then forms a porous barrier of constant thickness which induces a linear rate law due to the steady-state oxygen diffusion. Titanium cannot diffuse across the continuous crack. During the linear kinetics period several layers of constant thickness, separated by a continuous crack, spread out.     

Synthesis of bandlimited signals with independent amplitude and phase modulation

The synthesis of a bandpass bandlimited signal with independent AM and PM channels is considered, where the bandwidth of each of the two information signals is required to be less than or equal to half the bandwidth of the bandpass signal. A simple iterative algorithm for generation of the bandpass signal is proposed, and sample results are presented. It is shown that this approach may be useful in simultaneous amplitude phase transmission systems even when the number of iterations is small.     

Interactions in biofilms between Listeria monocytogenes and resident microorganisms from food industry premises

Twenty nine bacterial strains were grown as binary culture biofilms with Listeria monocytogenes to assess their influence on the settlement of the latter on stainless steel coupons. Most of the strains had been isolated from food processing plants after cleaning and disinfection and were tentatively identified by the APILAB Plus 3.3.3 database (bioMerieux). Sixteen of them decreased L. monocytogenes biofilm colony forming units (CFU) counts. Three strains, Bacillus sp. CCL 9 an unidentified Gram-positive strain CCL 59 and Pseudomonas fluorescens E9. 1, led to a 3-log difference in CFU counts between the pure L. monocytogenes biofilms and the mixed biofilms. Eleven strains had no effect and only four, Kocuria varians CCL 73, Staphylococcus capitis CCL 54, Stenotrophomonas maltophilia CCL 47 and Comamonas testosteroni CCL 24, had a positive effect, with a 0.5- to 1.0-log increase in the L. monocytogenes biofilm CFU counts. On its own, L. monocytogenes settled as single cells, but in binary biofilms, different spatial arrangements were observed: (i) with K. varians CCL 73, K. varians CCL 56 and S. capitis CCL 54, L. monocytogenes cells gathered around the microcolonies of the partner strain; (ii) with the two Gram-negative strains, C. testosteroni CCL 24 and CCL 25, L. monocytogenes cells formed its own microcolonies. No link could be found between the exopolysaccharide production capacity of the bacterial strains in pure-culture biofilms and their effect on the L. monocytogenes population in mixed biofilms. With one strain, C. testosteroni CCL 24, adding filter-sterilized supernatant from a pure-culture biofilm to a pure culture of L. monocytogenes increased the number of L. monocytogenes cells adhering to the stainless steel coupons and forming microcolonies. This study suggests that the "house flora" can have a strong effect on the likelihood of finding L. monocytogenes on inert surfaces.     

Removal of industrial cutting oil from oil emulsions by polymeric ultra- and microfiltration membranes

The utilization of micro- and ultrafiltration with polymeric membranes for treatment of industrial cutting oil emulsion was investigated. The performance of 14 different membranes with pore sizes in the range of 1-800 nm, representing 8 different materials and varying hydrophobicity, was determined experimentally. Membrane permeances between 1.6 and 939 L m 2 h(-1) bar(-1) have been observed for the different samples as well as oil rejections between 3.42% and 99.99%. Membrane pore size and contact angle showed little influence on both values, while an interesting correlation is displayed to the individual membranes' capillary pressures. A possible explanation for this phenomenon is suggested based on the formation of oil films on the membrane surface. From the investigated membranes, the best-suited one for cutting oil treatment was selected and subjected to further experiments. The effect of process temperatures between 22 and 43 degrees C and of feed oil concentrations between 0 and 20 vol % on the removal performance was determined. The results correspond to the explanation suggested previously.     

Dress and Ange: coercing the address of highly personal body-centric issues

This paper compares two interactive interfaces, Dress and Ange, designed to facilitate an experiential address of the user or viewers relationship to touch. Dress, a polypropylene dress fitted with small counters, which offer glimpses of human flesh for sale, is a shop that sells the possibility to touch human skin. The sales-person wears this body-shop and wanders through public domains inviting people to pull on a pearl of their choice and, thereby, expose a parcel of skin that they are to caress gently, momentarily with their fingertips. The second device, Ange, consists of a transparent corset with metal rib-like protuberances. Through the strategic use of flex sensors, these rib-keys act as points of actuation and volume control levers for corresponding sound samples. Ange has been designed to be exhibited, performed or worn in the public domain in a similar way to Dress. The inspiration and consequent design of both Dress and Ange will be discussed and compared, as will their public exhibition and performance in order to demonstrate the effectiveness of these design solutions. In conclusion, the value of particular design strategies to coerce or seduce a viewer to address highly personal issues, will be raised.     

Adaptive Low Power Listening for Wireless Sensor Networks

Most sensor networks require application-specific network-wide performance guarantees, suggesting the need for global and flexible network optimization. The dynamic and nonuniform local states of individual nodes in sensor networks complicate global optimization. Here, we present a cross-layer framework for optimizing global power consumption and balancing the load in sensor networks through greedy local decisions. Our framework enables each node to use its local and neighborhood state information to adapt its routing and MAC layer behavior. The framework employs a flexible cost function at the routing layer and adaptive duty cycles at the MAC layer in order to adapt a node's behavior to its local state. We identify three state aspects that impact energy consumption: 1) number of descendants in the routing tree, 2) radio duty cycle, and 3) role. We conduct experiments on a test-bed of 14 mica2 sensor nodes to compare the state representations and to evaluate the framework's energy benefits. The experiments show that the degree of load balancing increases for expanded state representations. The experiments also reveal that all state representations in our framework reduce global power consumption in the range of one-third for a time-driven monitoring network and in the range of one-fifth for an event-driven target tracking network.     

Vancomycin-susceptible dairy and clinical enterococcal isolates carry vanA and vanB genes

A total of 109 enterococcal isolates from dairy food products and from human and dog infections, isolated in Portugal, and 26 type and reference strains of the genus Enterococcus were screened for vancomycin resistance. MIC values, both for vancomycin and teicoplanin, were determined. The genetic relatedness of isolates carrying either vanA and/or vanB was determined using Pulsed Field Gel Electrophoresis. For vanA carrying isolates, transposon Tn1546 was partially mapped using PCR. None of the 59 dairy isolates was resistant to vancomycin. Among the 50 clinical isolates, only one, carrying vanB, behaved as resistant, with a MIC value of 256 microg/mL. The type and reference strains used were susceptible both to vancomycin and teicoplanin. vanA was found in 37% of the dairy isolates and 40% of the clinical isolates. vanB was only detected in 18% of the clinical, both human and dog, isolates. PCR partial mapping of Tn1546 revealed 23 different patterns among 42 isolates. Some patterns were shared between dairy and clinical isolates. Using Pulsed Field Gel Electrophoresis six groups of isolates were found to be genetically undistinguishable and grouping was found to be geographically and location specific/related. No genetic relatedness was found between isolates from dairy, human and veterinary sources. These results show that an incomplete and/or unfunctional Tn1546 element may explain the absence of resistant behaviour in the studied isolates, even when vanA gene is present. Moreover, the work reported shows that both clinical (human and animal) and dairy isolates have been in contact with VanA genotype of resistance and suggest that dissemination of vanA gene has been through transposable elements, like Tn1546, and not by clonal dissemination of a resistant strain. Therefore, a national strategy should be implemented to survey both vancomycin resistance and its genetic dissemination.