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Electron ratchet effect in semiconductor devices and artificial materials with broken centrosymmetry

Studies on nonlinear electron transport in nanometer-sized semiconductor devices with broken centrosymmetry are reviewed. In these devices, an applied alternating (rocking) electric field induces a net flow of electrons in the direction perpendicular to that of the applied field. Such an electron ratchet effect has been observed in a number of differently designed devices, fabricated from two type

BTKbase, mutation database for X-linked agammaglobulinemia (XLA)

X-linked agammaglobulinemia (XLA) is an immunodeficiency caused by mutations in the gene coding for Bruton's agammaglobulinemia tyrosine kinase (BTK). A database (BTKbase) of BTK mutations has been compiled and the recent update lists 463 mutation entries from 406 unrelated families showing 303 unique molecular events, In addition to mutations, the database also lists variants or polymorphisms. Ea

"Shim pulses" for NMR spectroscopy and imaging

A way to use adiabatic radiofrequency pulses and modulated magnetic-field gradient pulses, together constituting a "shim pulse," for NMR spectroscopy and imaging is demonstrated. These pulses capitalize on phase shifts derived from probe gradient coils to compensate for nonlinear intrinsic main magnetic field homogeneity for spectroscopy, as well as for deviations from linear gradients for imaging

Characterization of two recombinant PDE3 (cGMP-inhibited cyclic nucleotide phosphodiesterase) isoforms, RcGIP1 and HcGIP2, expressed in NIH 3006 murine fibroblasts and Sf9 insect cells

cDNAs encoding PDE3 [cGMP-inhibited cyclic nucleotide phosphodiesterase (cGI PDE)] isoforms, cGIP1 and cGIP2, have been cloned from rat (R) and human (H) cDNA libraries. The deduced amino acid sequences of RcGIP1 and HcGIP2 are very similar in their conserved catalytic domains but differ in their N-terminal regulatory domains [Meacci, E., et al. (1992) Proc. Natl. Acad. Sci. U.S.A. 89, 3721-3725;

Forecasting and evaluation of traffic safety impacts: driving assistance systems against road infrastructure measures

The authors examine the use of a one-variable first-order grey model ( GM( 1,1)), to model and forecast the trend of the level of cumulative traffic accident severity for strategic scenarios for implementation of driving assistance systems, physical infrastructure redesign and combinations of the two categories of measures. The accident severity levels ( in terms of fatalities and hospitalisations

Global dissipative solutions of the Camassa-Holm equation

This paper is devoted to the continuation of solutions to the Camassa-Holm equation after wave breaking. By introducing a new set of independent and dependent variables, the evolution problem is rewritten as a semilinear hyperbolic system in an L-infinity space, containing a non-local source term which is discontinuous but has bounded directional variation. For a given initial condition, the Cauch

Reduction of atrial fibrillation burden by atrial overdrive pacing: experience with an improved algorithm to reduce early recurrences of atrial fibrillation

Two independent studies have revealed a potential limitation of post-mode switch overdrive pacing (PMOP), which is its delayed start. We conducted a prospective, randomized, single blind, crossover design study (the post-long pause overdrive pacing study) to test the efficacy of an improved version of PMOP (PMOPenhanced). A total of 45 patients were enrolled, of whom 41 were analysed. The median n

Fabrication and time-resolved studies of visible microdisk lasers

We report on the fabrication and characterization of microdisk lasers emitting at around 650 nm. The structures were grown by metalorganic vapor phase epitaxy and processed using electron beam lithography and wet etching. Time-resolved photoluminescence measurements done at low temperature show a lasing threshold of 60 muW average power. A redshift in the whispering modes energy is observed. (C) 2

Stockholmarnas resvanor – mellan trängselskatt och klimatdebatt

Popular Abstract in Swedish Avhandlingen belyser vad resvanor är, hur storskaliga trafikreglerande åtgärder tas emot samt hur storstadsbornas resmönster kan bli miljömässigt hållbara på lång sikt. Jag diskuterar dessutom problem och möjligheter i skärningsområden mellan olika vetenskapliga discipliner som griper sig an dessa frågor. De viktigaste slutsatserna gäller för det första det vetenskapligThis thesis examines the concept of travel habits, public responses to large-scale traffic congestion regulations and how travel patterns of urban dwellers can be made environmentally sustainable in the long term. It also examines the interrelationships of different scientific disciplines dealing with urban travel. The main conclusions relate to the scientific concept of habit. This concept and th

Experience influences oviposition behaviour in two pyralid moths, Ephestia cautella and Plodia interpunctella

We investigated the importance of experience for oviposition behaviour in two pyralid moths, the almond moth, Ephestia cautella, and the Indian meal moth, Plodia interpunctella. We used two diets one based on wheat and the other consisting of nut-containing chocolate. Larvae were reared in one of the two diets (larval feeding) and then adults were exposed to the two diets during and after eclosion

The genus Pseudexechia Tuomikoski re-characterized, with a review of European species (Diptera: Mycetophilidae)

The genus Pseudexechia Tuomikoski is re-characterized and described, including a thorough morphological study of the male and female terminalia, providing homology assessment of the various parts and substructures. The 25 currently known species of Pseudexechia are tentatively grouped into four species groups that are characterized mainly by structures of the male terminalia: the canalicula group

An Electrochemical Study into the Interaction between Complement-Derived Peptides and DOPC Mono- and Bilayers

Electrochemical methods employing the hanging mercury drop electrode were used to study the interaction between variants of the complement-derived antimicrobial peptide CNY21 (CNYITELRRQH ARASHLGLAR) and dioleoyl phosphatidylcholine (DOPC) monolayers. Capacitance potential and impedance measurements showed that the CNY21 analogues investigated interact with DOPC monolayers coating the mercury drop

Subglacial decoupling at the sediment/bedrock interface: a new mechanism for rapid flowing ice

Abstract in UndeterminedOn millennial or even centennial time scales, the activity of rapid flowing ice can affect climate variability and global sea level through release of meltwater into the ocean and positive feedback loops to the climate system. At the surge-type glacier Bruarjokull, an outlet of the Vatnajokull ice cap, eastern Iceland, extremely rapid ice flow was sustained by overpressuriz

Mercaptobenzothiazole or the mercapto-mix: which should be in the standard series?

Mercaptobenzothiazole (MBT) compounds are well known contact allergens. To detect rubber allergic patients we use both MBT (2% in petrolatum) and a mercapto-mix with 4 constituents of 0.5% each in our standard series. In this article the EECDRG presents data of in total 32 475 consecutive tested patients attending the respective contact dermatitis clinics from 11 centres in Europe to determine if

Exploring User Requirements for Non-visual Mobile Navigation Systems

This paper describes an explorative user study of how two different user groups experience current, as well as envisioned new mobile navigation systems. Two groups have been the primary target in this study; a group of elderly people and a group of relatively young university students that were visually impaired. The study consisted of three parts: a focus group/test, a diary study and a design wo

Fabrication of cantilever based mass sensors integrated with CMOS using direct write laser lithography on resist

A CMOS compatible direct write laser lithography technique has been developed for cantilever fabrication on pre-fabricated standard CMOS. We have developed cantilever based sensors for mass measurements in vacuum and air. The cantilever is actuated into lateral vibration by electrostatic excitation and the resonant frequency is detected by capacitive readout. The device is integrated on standard C

Relative concentrations of hK2/PSA mRNA in benign and malignant prostatic tissue

BACKGROUND. Prostate-specific antigen (PSA/KLK3) and human kallikrein 2 (hK2/KLK2) belong to the human kallikrein gene family. These two highly homologous genes are specifically expressed in the prostate under androgen control. Expression of these is regulated by similar mechanisms but changes in their relative expression have been observed in prostate cancer. METHODS. We determined the relative l

The potential of native parasitoids for the control of Mexican bean beetles: A genetic and ecological approach

Bruchid beetles in the genus Zabrotes are important pests of field and stored beans all around the world and cause enormous economical losses in Mexico and Central America. Native parasitoids have been successfully used to suppress infestations by bruchid beetles in Africa, but few studies have assessed their potential to reduce seed damage in the New World and no successful biological control pro