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Pools and fluxes of carbon in three Norway spruce ecosystems along a climatic gradient in Sweden

This paper presents an integrated analysis of organic carbon (C) pools in soils and vegetation, within-ecosystem fluxes and net ecosystem exchange (NEE) in three 40-year old Norway spruce stands along a north-south climatic gradient in Sweden, measured 2001-2004. A process-orientated ecosystem model (CoupModel), previously parameterised on a regional dataset, was used for the analysis. Pools of so

Improved bone-forming functionality on diameter-controlled TiO2 nanotube surface

The titanium dioxide (TiO2) nanotube surface enables significantly accelerated osteoblast adhesion and exhibits strong bonding with bone. We prepared various sizes (30-100 nm diameter) of titanium dioxide (TiO2) nanotubes on titanium substrates by anodization and investigated the osteoblast cellular behavior in response to these different nanotube sizes. The unique and striking result of this stud

Seasonal photoreactivity of dissolved organic matter from lakes with contrasting humic content

We studied seasonal variability in photodegradation of dissolved organic carbon (DOC) resulting from artificial ultraviolet-A (UV-A) and UV-B irradiation. Water samples were taken approximately monthly from the surface layers of two oligotrophic lakes with contrasting humic content, situated in southern Sweden. Lake water was filter-sterilized (0.2 μm) and exposed to artificial UV radiation in qua

Mechanisms of cache retrieval in long-term hoarding birds

Food hoarding and memory have primarily been studied in two bird families, the Corvidae (crows, jays, nutcrackers, etc.) and the Paridae (tits, titmice and chickadees). In both families there are species that hoard large quantities of seeds and nuts in the autumn and depend on these stores during the winter. Caches are concealed or highly inconspicuous and the most efficient way to retrieve them i

The challenge of managing patients with polyarteritis nodosa.

Purpose of review In this short review we focus on the problems faced by clinicians caused by the changing definitions of polyarteritis nodosa. Recent findings the term polyarteritis nodosa has been used for more than 100 years as a diagnostic term for patients with systemic vasculitis, however, specific vasculitides have been singled out like branches being chopped off a tree. Now, so little is l

Baseline demographic characteristics of subjects enrolled in international quadrivalent HPV (types 6/11/16/18) vaccine clinical trials

BACKGROUND: In Phase II/III trials, administration of quadrivalent human papillomavirus (HPV) (types 6/11/16/18) L1 virus-like-particle vaccine was highly effective in preventing HPV6/11/16/18-related cervical intraepithelial neoplasia and non-invasive cervical cancer in women aged 16-26 years who were naïve to these HPV types at enrollment. However, the makeup and extent of catch-up vaccination p

AAPS-FDA workshop white paper: Microdialysis principles, application and regulatory perspectives

Many decisions in drug development and medical practice are based on measuring blood concentrations of endogenous and exogenous molecules. Yet most biochemical and pharmacological events take place in the tissues. Also, most drugs with few notable exceptions exert their effects not within the bloodstream, but in defined target tissues into which drugs have to distribute from the central compartmen

An approach to remove the clutter and detect the target for ultra-wideband through-wall imaging

Through-wall imaging (TWI) is important from the point of view of rescue operations and surveillance. Several researchers have been working in this field but have still not obtained any concrete results. TWI using narrow band radar faces the problem of low resolution whereas ultra-wideband (UWB) radar provides better resolution, classification and low loss for the imaging signals. TWI faces many c

Guiding molecular motors with nano-imprinted structures

This work, for the first time, demonstrates that nano-imprinted samples, with 100 nm wide polymer lines, can act as guides for molecular motors consisting of motor proteins actin and myosin. The motor protein function was characterized using fluorescence microscopy and compared to actomyosin motility on non-structured nitrocellulose surfaces. Our results open for further use of the nano-imprint te

Cervical or thoracic anastomosis after esophageal resection and gastric tube reconstruction - A prospective randomized triol comparing sutured neck anastomosis with stapled intrathorocic anastomosis

Objective: The purpose of the study was to compare in prospective randomized fashion a manually sutured esophagogastric anastomosis in the neck and a stapled in the chest after esophageal resection and gastric tube reconstruction. Summary Background Data: Despite the fact that all reconstructions after esophagectomy will result in a cervical or a thoracic anastomosis, controversy still exists as t

Small-scale spatial pattern of web-building spiders (Araneae) in alfalfa: Relationship to disturbance from cutting, prey availability, and intraguild interactions

Understanding the development of spatial patterns in generalist predators will improve our ability to incorporate them into biological control programs. We studied the small-scale spatial patterns of spider webs in alfalfa by analyzing the relationship between web locations over distances ranging from 4 to 66 cm. Using a coordinate-based spatial statistic (O-ring) and assuming a heterogeneous dist

Effects of systematic exposure assessment errors in partially ecologic case-control studies.

BACKGROUND: In ecologic studies, group-level rather than individual-level exposure data are used. When using group-level exposure data, established by sufficiently large samples of individual exposure assessments, the bias of the effect estimate due to sampling errors or random assessment errors at the individual-level is generally negligible. In contrast, systematic assessment errors may produce

Mouse and rat cystatin C: Escherichia coli production, characterization and tissue distribution

Recombinant mouse (Mus musculus) and rat (Rattus norvegicus) cystatin C were produced by expression in Escherichia coli, isolated and functionally characterized. The mouse and rat inhibitors were both fully active in titrations of papain. Determination of equilibrium constants for dissociation (Ki) for their complexes with the target proteinase, cathepsin B, produced values not largely different f

Amperometric monitoring of redox activity in living yeast cells: comparison of menadione and menadione sodium bisulfite as electron transfer mediators

An amperometric method was applied for real-time monitoring of intracellular redox enzyme activity. Baker’s yeast (Saccharomyces cerevisiae) cells were immobilized on platinum microband electrodes and mediated anodic currents were measured. The currents were observed in the absence and in the presence of glucose as a source of reducing equivalents, NADH and NADPH. 2-Methyl-1,4-naphthoquinone (mena