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Adsorption of Cs on InAs(111) surfaces

Caesiated InAs(111)B (1 x 1) and InAs(111)A (2 x 2) surfaces have been studied by photoelectron spectroscopy. On the InAs(111)B a new (root 3 x root 3)R30 degrees reconstruction was observed. During Cs evaporation remarkably small changes are observed in the lone pair states, and no sign of an accumulation layer at the surface can be observed. Instead, the additional charge provided by Cs is rapid

Longitudinal movements and resulting shear strain of the arterial wall

There has been little interest in the longitudinal movement of the arterial wall. It has been assumed that this movement is negligible compared with the diameter change. Using a new high-resolution noninvasive ultrasonic method, we measured longitudinal movements and diameter change of the common carotid artery of 10 healthy humans. During the cardiac cycle, a distinct bidirectional longitudinal m

The evolution of repeated mating under sexual conflict

In insects, repeated mating by females may have direct effects on female fecundity, fertility, and longevity. In addition, a female's remating rate affects her fitness through mortality costs of male harassment and ecological risks of mating such as predation. We analyse a model where these female fitness factors are put into their life-history context, and traded against each other, while account

Screening of two complementary collections of Saccharomyces cerevisiae to identify enzymes involved in stereo-selective reductions of specific carbonyl compounds: an alternative to protein purification.

Two collections of Saccharomyces cerevisiae strains, having open reading frames (ORFs) either overexpressed or deleted, were screened to identify cytosolic NADPH-dependent reductases involved in stereo-selective reductions of specific carbonyl compounds. As model compounds diacetyl (diketone) and ethyl acetoacetate (3-oxo ester) were used. The reductases encoded by YBR149w, YDR368w, YMR226c and YO

Quantum control of energy flow in light harvesting.

Coherent light sources have been widely used in control schemes that exploit quantum interference effects to direct the outcome of photochemical processes. The adaptive shaping of laser pulses is a particularly powerful tool in this context: experimental output as feedback in an iterative learning loop refines the applied laser field to render it best suited to constraints set by the experimenter.

Incomplete degradation of polycyclic aromatic hydrocarbons in soil inoculated with wood rotting fungi and their effect on the indigenous soil bacteria.

Soil artificially contaminated with fluorene, phenanthrene, pyrene, and benz[a]anthracene was inoculated with the wood-rotting fungi Pleurotus ostreatus and Antrodia vaillantii. During 12 weeks of incubation, polycyclic aromatic hydrocarbon (PAH) degradation and the formation of persistent degradation products were monitored by chemical analysis. In addition, the effect on the indigenous soil bact

Parental perceptions of health care for children with chronic illness--a population-based study in a Swedish primary care district

The division of responsibilities between specialized and primary health care for children with chronic illness is unclear. The utilization and perceptions of primary and specialized care were examined by means of a questionnaire mailed to the parents of all chronically ill children and a randomly selected control group. No difference in sociodemographic variables of responders (70%) and nonrespond

Uncertainties in predicting tourist travel flows under scenarios of climate change

Tourism is largely dependent on climatic and natural resources. For example, "warmer'' climates generally constitute preferred environments for recreation and leisure, and natural resources such as fresh water, biodiversity, beaches or landscapes are essential preconditions for tourism. Global environmental change threatens these foundations of tourism through climate change, modifications of glob

Prediction and rationalization of the pH dependence of the activity and stability of family 11 xylanases

This paper presents a study of the pH dependence of the activity and stability of a set of family 11 xylanases for which X-ray structures are available, using the PROPKA approach. The xylanases are traditionally divided into basic and acidic xylanases, depending on whether the catalytic acid is hydrogen bonded to an Asn or Asp residue. Using X-ray structures, the predicted pH values of optimal act

Early evolution of multifocal optics for well-focused colour vision in vertebrates.

Jawless fishes (Agnatha; lampreys and hagfishes) most closely resemble the earliest stage in vertebrate evolution and lamprey-like animals already existed in the Lower Cambrian [about 540 million years ago (MYA)]. Agnathans are thought to have separated from the main vertebrate lineage at least 500 MYA. Hagfishes have primitive eyes, but the eyes of adult lampreys are well-developed. The southern

Approved IFCC reference method for the measurement of HbA1c in human blood.

HbA1C is the stable glucose adduct to the N-terminal group of the beta-chain of HbA0. The measurement of HbA1c in human blood is most important for the long-term control of the glycaemic state in diabetic patients. Because there was no internationally agreed reference method the IFCC Working Group on HbA1c Standardization developed a reference method which is here described. In a first step haemog

Exploring the context of the lung proteome within the airway mucosa following allergen challenge.

The lung proteome is a dynamic collection of specialized proteins related to pulmonary function. Many cells of different derivations, activation states, and levels of maturity contribute to the changing environment, which produces the lung proteome. Inflammatory cells reacting to environmental challenge, for example from allergens, produce and secrete proteins which have profound effects on both r

Measurement of stellar age from uranium decay

The ages of the oldest stars in the Galaxy indicate when star formationbegan, and provide a minimum age for the Universe. Radioactive dating ofmeteoritic material and stars relies on comparing the present abundanceratios of radioactive and stable nuclear species to the theoreticallypredicted ratios of their production. The radioisotope 232Th(half-life 14Gyr) has been used to date Galact

Hydrological function of a thin extensive green roof in southern Sweden

The runoff from and the water balance of a thin extensive green roof with sedum-moss have been studied. The soil cover is about 3 cm underlain by a thin drainage layer. The water balance is determined on a monthly basis. The runoff from the green roof is much reduced compared to runoff from hard roofs because of evapotranspiration. The annual runoff is rather close to that of natural river basins.

Flight performance during hunting excursions in Eleonora's falcon Falco eleonorae

Among birds, falcons are high-performance flyers, in many cases adapted for aerial hunting and hence suitable targets for investigating limits to flight performance. Using an optical range finder, we measured flight tracks of Eleonoras falcon (Falco eleonorae), a species breeding in the Mediterranean region and specialised for hunting autumn passage bird migrants, when commuting between their nest

Kinetics of the selective reduction of NO with NH3 over a V2O5(WO3)/TiO2 commercial SCR catalyst

In order to clarify the mechanism of the selective catalytic reduction of nitric oxide with ammonia over a V2O5(WO3)/TiO2 commercial SCR catalyst, measurements were made on the reaction rate, r(NO), as a function of partial pressure of nitric oxide, P-NO, partial pressure of ammonia, P-NH3, and partial pressure of oxygen, P-O2, from 513 to 553 K under steady-state conditions. The adsorption of NO

Low levels of IgM antibodies against phosphorylcholine-A potential risk marker for ischemic stroke in men

Background: Natural antibodies specific for phosphorylcholine (anti-PC) have been implicated as protective factors in atherosclerosis. We herein determined the relationship between IgM anti-PC and incidence of cardiovascular disease (CVD). Methods: We studied 349 incident cases (200 men) of first events of CVD (coronary heart disease (CHD; n = 203 or ischemic stroke; n = 146) and 693 age- and sex-

Holocene palaeoecology and climate history of South Georgia (sub-Antarctica) based on a macrofossil record of bryophytes and seeds

The results are presented of a detailed plant macrofossil analysis of a C-14 dated Holocene organic sequence from a sub-Antarctic island, South Georgia. In the peat infilling of a rock basin 31 bryophyte species and many of the principal species of the present-day angiosperm flora, associated with bog communities, have been identified. The zonation of the bryophytes and the seeds and fruits shows