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Compensation for longitudinal chromatic aberration in the eye of the firefly squid, Watasenia scintillans

The camera eyes of fishes and cephalopods have come forth by convergent evolution. In a variety of vertebrates capable of color vision, longitudinal chromatic aberration (LCA) of the optical system is corrected for by the exactly tuned longitudinal spherical aberration (LSA) of the crystalline lens. The LSA leads to multiple focal lengths, such that several wavelengths can be focused on the retina

Growth and reactivity of titanium oxide ultrathin films on Ni(110)

Soft X-ray photoelectron spectroscopy (SXPS) and X-ray absorption near-edge structure (XANES) have been combined with low-energy electron diffraction (LEED) to examine the growth of titanium dioxide thin films on Ni(110). Depending on the initial titanium coverage, the formation of two different films is observed, a quasi-hexagonal phase and a film with rutile (110) rods. Spectroscopy (SXPS and XA

Symbolic technologies: Machines and the Marxian notion of fetishism

By extending the Marxian theory of fetishism from money and commodities to machines, we may achieve an epistemological shift in our understanding of the foundations of 'technological development'. The first part of the article discusses previous definitions of fetishism in order to distil some central themes that appear to be particularly significant to the argument on machine fetishism. It is arg

Influence of recirculation flow rate on the performance of anaerobic packed-bed bioreactors treating potato-waste leachate

The performance of anaerobic, packed-bed bioreactors treating leachate from potato waste was evaluated in terms of organic loading rate (OLR) as well as the recirculation flow rate. Two 1 litre bioreactors, filled with porous glass beads as biofilm carriers and with continuous recirculation flow rates of 10 ml min(-1) and 20 ml min(-1) respectively, were used in the experiment. The OLR applied to

Electrostatic contributions to residue-specific protonation equilibria and proton binding capacitance for a small protein

Charge-charge interactions in proteins are important in a host of biological processes. Here we use C-13 NMR chemical shift data for individual aspartate and glutamate side chain carboxylate groups to accurately detect site-specific protonation equilibria in a variant of the B1 domain of protein G (PGB1-QDD). Carbon chemical shifts are dominated by changes in the electron distribution within the s

Amplified fragment length polymorphism analysis identifies hybrids between two subspecies of warblers.

In the western Pyrenees (Southwest France and Northwest Spain), a narrow hybrid zone exists between the common chiffchaff Phylloscopus (collybita) collybita and the Iberian chiffchaff Phylloscopus (c.) brehmii. In this zone, which is approximately 20 km wide, mixed matings and individuals singing the songs of both taxa occur at substantial frequencies (24 and 8.6%, respectively), suggesting freque

Paperboard packages exposed to static loads–finite element modelling and ­experiments

The aim of this study was to analyse the mechanical behaviour of paperboard packages subjected to static compressive loads. The study was divided in three parts and experiments and finite element analysis conducted for each part. First, a panel of paperboard was subjected to edge compressive loading as a means of checking the material model. Second, the package was cut into segments and each segme

Abnormal nuclear shape in solid tumors reflects mitotic instability

Abnormalities in nuclear morphology are frequently observed in malignant tissues but the mechanisms behind these phenomena are still poorly understood. In this study, the relation between abnormal nuclear shape and chromosomal instability was explored in short-term tumor cell cultures. Mitotically unstable ring and dicentric chromosomes were identified by fluorescence in situ hybridization at meta

Neutrino Sector with Majorana Mass Terms and Friedberg-Lee Symmetry

We examine a recently proposed symmetry/condition by Friedberg and Lee in the framework where three right-handed neutrinos are added to the spectrum of the three-family Minimal Standard Model. It is found that the right-handed neutrinos are very special, with respect to this symmetry. In the symmetry limit the neutrinos are massless and that may be a hint about why they are light. Imposed as a con

Affinity processing of cell-containing feeds using monolithic macroporous hydrogels, cryogels.

Monolithic macroporous hydrogels, "cryogels," are produced by polymerization in a partially frozen state when the ice crystals perform as a porogen. Cryogels have a unique combination of properties: (i) large (10-100 microm) pores; (ii) minimal non-specific interactions due to the hydrophilic nature of the polymers; (iii) porosities exceeding 80-90%; (iv) good mechanical stability. These propertie

Driving forces for phase separation and partitioning in aqueous two-phase systems

A set of simple analytical equations, derived from the Flory-Huggins theory, are used to identify the dominant driving forces for phase separation and solute (e.g., protein) partitioning, in the absence and presence of added electrolyte, in every general class of aqueous two-phase systems. The resulting model appears to capture the basic nature of two-phase systems and all trends observed experime

Exogenous NT-3 and NGF differentially modulate PACAP expression in adult sensory neurons, suggesting distinct roles in injury and inflammation

Expression of pituitary adenylate cyclase-activating polypeptide in sensory neurons varies with injury or inflammation. The neurotrophins NGF and NT-3 are profound regulators of neuronal peptidergic phenotype in intact and injured sensory neurons. This study examined their potential for modulation of PACAP expression in adult rat with intact and injured L4-L6 spinal nerves with or without immediat

Disturbed pubertal growth in girls treated for acute lymphoblastic leukemia

Pubertal growth was studied in 10 girls previously treated for acute lymphoblastic leukemia. The average age at menarche was 12.2 years, which is significantly lower (p less than 0.01) than the expected 13.1 years. Compared with normal girls, these girls showed a subnormal (p less than 0.05) peak height velocity during the second year before menarche. The remaining growth before menarche as well a

Elderly women's experiences of living with fall risk in a fragile body: a reflective lifeworld approach

The purpose of this qualitative study was to explore the lived experience of fall risk from a lifeworld perspective in elderly women with previous fragility fractures. Thirteen elderly women with a high risk of fall and fracture, aged 76-86, living in their own homes in rural areas, were recruited from a voluntary fracture prevention programme. All women had a history of fragility fractures and we

Analytic study of the steel liner near the equipment hatch in a 1 : 4 scale containment model

A containment scale-model test, performed at Sandia National Laboratories, was loaded by overpressurization and the first leak was concluded to be caused by tears in the steel liner found near the equipment hatch. These tears were located in the vicinity of the vertical fold in between the general curved part and the embossment (vertical bend line). A 3D finite element analysis of the region near

Individually adapted lightweight walking aids with moulded handles for patients with severely deforming chronic arthritis

Patients with severely deforming rheumatoid arthritis and impaired function of the upper extremity are often unable to use conventional walking aids. This report describes 42 such patients who were equipped with altogether 75 individually manufactured, lightweight walking aids (12 crutches, 12 forearm-crutches, 39 crutch-sticks and 12 sticks). A plaster cast of the patient's grip as well as analys