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Fifty thousand years of arctic vegetation change and megafauna diet

Although it is generally agreed that the Arctic flora is among the youngest and least diverse on Earth, the processes that shaped it are poorly understood. Here we present 50 thousand years (kyr) of Arctic vegetation history, derived from the first large-scale ancient DNA metabarcoding study of circumpolar plant diversity. For this interval we also explore nematode diversity as a proxy for modelli

Organoclay polypropylene nanocomposites under different electric field strengths

Functionalities of clay-polymer nanocomposites (CPN) are related to the degree of clay particle exfoliation and orientation within the polymer matrix. Exploration of new physical methods for such CPN processing is currently an active field of research. In the present work, organoclay polypropylene nanocomposites were prepared by melt intercalation and subsequently exposed to an electric field (E)

The risk of pneumococcal infections after immunization with pneumococcal conjugate vaccine compared to non-vaccinated inflammatory arthritis patients.

Objectives: To examine the risk of putative pneumococcal infections in adult arthritis patients on different anti-rheumatic drugs immunized with heptavalent pneumococcal conjugate vaccine (Prevenar 7; PCV7) and non-vaccinated individually matched arthritis patients. Method: All individuals in a cohort of 505 patients with rheumatoid arthritis (RA) or spondylarthropathy (SpA) receiving different an

LTX-109 is a Novel Agent for Nasal Decolonisation of Methicillin Resistant and Sensitive Staphylococcus aureus.

Nasal decolonisation has a proven effect on the prevention of severe Staphylococcus aureus infections and in the control of methicillin resistant S. aureus (MRSA). However, rising rates of resistance to antibiotics highlights the need for new substances for nasal decolonisation. LTX-109 is a broad spectrum, fast-acting bactericidal antimicrobial drug for topical treatment, which causes membrane di

A late Archaean radiating dyke swarm as possible clue to the origin of the Bushveld Complex

The Bushveld Complex in South Africa represents the world's largest intrusion of magnesium-and iron-rich magmas. The Bushveld magmas were emplaced beneath the Transvaal basin(1) similar to 2.06 billion years ago(2,3), but their origin remains elusive. The magmas may have formed in response to an upwelling mantle plume(4), ancient subduction5 or melting triggered by a meteorite impact(6). Here we u

Photoluminescence study of as-grown vertically standing wurtzite InP nanowire ensembles.

We demonstrate a method that enables the study of photoluminescence of as-grown nanowires on a native substrate by non-destructively suppressing the contribution of substrate photoluminescence. This is achieved by using polarized photo-excitation and photoluminescence and by making an appropriate choice of incident angle of both excitation beam and photoluminescence collection direction. Using T-p

Random mutagenesis of amelogenin for engineering protein nanoparticles.

Nanoparticles made from recombinant proteins offer excellent potential for several nanotechnological applications. However, only a very limited number of proteins are currently being used for such purposes due to limited availability and stability. Therefore, we have investigated the enamel matrix protein amelogenin as a new alternative protein for use as recombinant nanoparticles. Amelogenin is a

Polymorphisms in Genes Encoding Potential Mercury Transporters and Urine Mercury Concentrations in Populations Exposed to Mercury Vapor from Gold Mining.

Background: Elemental mercury (Hg0) is widely used in small-scale gold mining. Individuals working or living in mining areas have high urinary concentrations of Hg (U-Hg). Differences in genes encoding potential Hg-transporters may affect uptake and elimination of Hg. Objective: To identify single nucleotide polymorphisms (SNPs) in Hg-transporter genes that modify U-Hg. Methods: 1,017 men and wome

Computational De Novo Design of a Self-Assembling Peptide with Predefined Structure.

Protein and peptide self-assembly is a powerful design principle for engineering of new biomolecules. More sophisticated biomaterials could be built if both the structure of the overall assembly and that of the self-assembling building block could be controlled. To approach this problem, we developed a computational design protocol to enable de novo design of self-assembling peptides with predefin

Motor skills and school performance in children with daily physical education in school - a 9-year intervention study.

The aim was to study long-term effects on motor skills and school performance of increased physical education (PE). All pupils born 1990-1992 from one school were included in a longitudinal study over nine years. An intervention group (n = 129) achieved daily PE (5 × 45 min/week) and if needed one extra lesson of adapted motor training. The control group (n = 91) had PE two lessons/week. Motor ski

Which are the most important parameters for modelling carbon assimilation in boreal Norway spruce under elevated [CO2] and temperature conditions?

Photosynthesis is highly responsive to environmental and physiological variables, including phenology, foliage nitrogen (N) content, atmospheric CO2 concentration ([CO2]), irradiation (Q), air temperature (T) and vapour pressure deficit (D). Each of these responses is likely to be modified by long-term changes in climatic conditions such as rising air temperature and [CO2]. When modelling photosyn

III-V Nanowire MOSFETs in RF-Applications

InAs nanowires have been used to fabricate high-performance MOSFETs that have been integrated into small-scale RF-circuits. We describe the strategy for the design of the transistor architecture and present data for the DC and high-frequency performance. Studies of the 1/f-noise show competitive normalized noise spectral density although it suggests the presence of defects within the high-k film t

Next generation RNA-sequencing in prognostic subsets of chronic lymphocytic leukemia

Advances in next-generation RNA-sequencing have revealed the complexity of transcriptomes by allowing both coding and noncoding (nc) RNAs to be analyzed. However, limited data exist regarding the whole transcriptional landscape of chronic lymphocytic leukemia (CLL). In this pilot-study, we evaluated RNA-sequencing in CLL by comparing two subsets which carry almost identical or `` stereotyped'' B-c

Wind buffeting of large telescopes

Unsteady wind loads due to turbulence within the telescope enclosure are one of the largest dynamic disturbances for ground-based optical telescopes. The desire to minimize the response to the wind influences the design of the telescope enclosure, structure, and control systems. There is now significant experience in detailed integrated modeling to predict image jitter due to wind. Based on this e

Look and touch: multimodal sensory control of flower inspection movements in the nocturnal hawkmoth Manduca sexta

A crucial stage in the interaction between pollinators and plants is the moment of physical contact between them, known as flower inspection, or handling. Floral guides - conspicuous colour markings, or structural features of flower corollas - have been shown to be important in the inspecting behaviour of many insects, particularly in diurnal species. For the nocturnal hawkmoth Manduca sexta tacti

Pregnancy Rate and Outcome in Swedish Women With Turner Syndrome EDITORIAL COMMENT

The rate of spontaneous pregnancies in women with Turner syndrome (TS) is low (2% to 5%). Oocyte donation is an option for these women and enables many to become pregnant. Some investigators question the use of pregnancy induction in TS because of the high risk for aortic dissection or other serious cardiac events. A cardiac evaluation is recommended before pregnancy is planned in TS. Among patien

Assessing foliar chlorophyll contents with the SPAD-502 chlorophyll meter: a calibration test with thirteen tree species of tropical rainforest in French Guiana

Chlorophyll meters such as the SPAD-502 offer a simple, inexpensive and rapid method to estimate foliar chlorophyll content. However, values provided by SPAD-502 are unitless and require empirical calibrations between SPAD units and extracted chlorophyll values. Leaves of 13 tree species from the tropical rain forest in French Guiana were sampled to select the most appropriate calibration model am