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From Sensations to Concepts : a Proposal for Two Learning Processes

This article presents two learning processes in order to explain how children at an early age can transform a complex sensory input to concepts and categories. The first process constructs the perceptual structures that emerge in children’s cognitive development by detecting invariants in the sensory input. The invariant structures involve a reduction in dimensionality of the sensory information.

3D printable non-isocyanate polyurethanes with tunable material properties

Green chemistry-based non-isocyanate polyurethanes (NIPU) are synthesized and 3D-printed via rapid, projection photopolymerization into compliant mechanisms of 3D structure with spatially-localized material properties. Trimethylolpropane allyl ether-cyclic carbonate is used to couple the unique properties of two types of reaction chemistry: (1) primary diamine-cyclic carbonate ring-opening conjuga

Adipose cell size changes are associated with a drastic actin remodeling

Adipose tissue plays a major role in regulating whole-body insulin sensitivity and energy metabolism. To accommodate surplus energy, the tissue rapidly expands by increasing adipose cell size (hypertrophy) and cell number (hyperplasia). Previous studies have shown that enlarged, hypertrophic adipocytes are less responsive to insulin, and that adipocyte size could serve as a predictor for the devel

Investigation of autofluorescence in zooplankton for use in classification of larval salmon lice

We present autofluorescence of six zooplankton species, including salmon lice (Lepeophtheirus salmonis), for the purpose of classification in marine environments. Using a 410 nm excitation wavelength, we find that all measured zooplankton species exhibit broad cyan fluorescence centered around 510–520 nm. Furthermore, salmon lice show an absence of red fluorescence from undigested chlorophyll, whi

Animal Signals : Dirty Dancing in the Dark?

The use of highly visible body colours as signals during courtship is well known from animals active in brighter light. Now a sexually dimorphic colouration signal has been discovered in a nocturnal moth, suggesting that visual courtship rituals might even occur at night.

Incidence of Intraocular Lens Exchange after Cataract Surgery

Intraocular lens (IOL) exchange after cataract surgery is unusual but may be associated with suboptimal visual outcome. The incidence of IOL exchange has not been consistently estimated. Such information is invaluable when counseling patients prior to cataract surgery. We examined the incidence of, and indications and risk factors for, IOL exchange after cataract surgery. We also assessed visual o

PTPD : Predicting therapeutic peptides by deep learning and word2vec

Background In the search for therapeutic peptides for disease treatments, many efforts have been made to identify various functional peptides from large numbers of peptide sequence databases. In this paper, we propose an effective computational model that uses deep learning and word2vec to predict therapeutic peptides (PTPD).∗: Results Representation vectors of all k-mers were obtained through wor

Framtidens klimat är redan på gång

Ledare•En sak är helt säker, framtiden kommer att vara annorlunda från hur vi har haft det, och i dag har det. Det skriver Markku Rummukainen i denna klimatkrönika. På måndag den 4 mars håller han en föreläsning om klimatförändringar och oundvikliga klimatåtgärder på Halmstads Stadsbibliotek i serien ”Klimatet & vi” som går under våren.

Properties of predictive gain modulation in a dragonfly visual neuron

Dragonflies pursue and capture tiny prey and conspecifics with extremely high success rates. These moving targets represent a small visual signal on the retina and successful chases require accurate detection and amplification by downstream neuronal circuits. This amplification has been observed in a population of neurons called small target motion detectors (STMDs), through a mechanism we term pr

Flow sorting of mouse pancreatic B cells by forward and orthogonal light scattering

Mouse islet cell suspensions were separated into subpopulations based on forward low angle and orthogonal scattered light. Separated fractions were analyzed for hormone content by radioimmunoassays. The pancreatic B‐cells had the highest orthogonal light scattering, while they overlapped in forward low angle light scattering with other endocrine (glucagon, pancreatic polypeptide and somatostatin c

The Spatial Dimension of Import Competition

Exposure to international competition on a country level has been shown to improve the efficiency of domestic producers. We contribute to this literature by assessing whether the distance between producers and importers, within a country, matters for import competition effects at product level. Using detailed geographical information about the location of all manufacturing firms in Sweden during t

HIV-2 as a model to identify a functional HIV cure

Two HIV virus types exist: HIV-1 is pandemic and aggressive, whereas HIV-2 is confined mainly to West Africa and less pathogenic. Despite the fact that it has been almost 40 years since the discovery of AIDS, there is still no cure or vaccine against HIV. Consequently, the concepts of functional vaccines and cures that aim to limit HIV disease progression and spread by persistent control of viral

Enzyme-free optical DNA mapping of the human genome using competitive binding

Optical DNA mapping (ODM) allows visualization of long-range sequence information along single DNA molecules. The data can for example be used for detecting long range structural variations, for aiding DNA sequence assembly of complex genomes and for mapping epigenetic marks and DNA damage across the genome. ODM traditionally utilizes sequence specific marks based on nicking enzymes, combined with

Does peak bone mass correlate with peak bone strength? Cross-sectional normative dual energy X-ray absorptiometry data in 1052 men aged 18-28 years

Background: Areal bone mineral density (aBMD) estimated by dual-energy X-ray absorptiometry (DXA) is used to estimate peak bone mass, define osteoporosis and predict fracture. However, as aBMD is calculated as bone mineral content (BMC) divided by the scanned area, aBMD displays an inverse relationship with bone size. In a skeleton that is increasing in size, this is a problem, as bone size is an

Specific pancreatic β-cell surface antigens recognized by a xenogenic antiserum

An antiserum (R4) from a rabbit immunized with suspensions of C57BL/6J ob/ob mouse islet cells contains antibodies which in a 125I-protein A radioligand assay can be demonstrated to bind to single cell suspensions of normal Naval Medical Research Institute (NMRI) mouse islet cells. The binding of 125I-protein A to islet cells was about four times that of normal rabbit serum (NRS) after incubation

Metabolic and underlying causes of diabetes mellitus

It is emphasized that animal models should be used to study specific genotypic or phenotypic expressions associated with diabetes rather than assuming a single animal model can reflect diverse forms of the human disease. Diabetic and normal animals are reviewed on the basis of their usefulness as models of genetic, viral, and chemically induced diabetes, including the often associated immune pheno

Effects of islet cell surface antibodies and complement on the release of insulin and chromium from perifused β cells

The dynamics of insulin and chromium release from prelabelled rat pancreatic islet cells were studied by perifusion of cells supported in a column of Bio-Gel P-2 polyacrylamide beads. The column-perifused β cells released insulin in a biphasic pattern in response to 30 mmol/l D-glucose and in a monophasic pattern to 20 mmol/l L-arginine. Rat islet cells, first exposed to a rabbit anti-rat islet c

The low dose streptozotocin murine model of Type 1 (insulin-dependent) diabetes mellitus : Studies in vivo and in vitro of the modulating effect of sex hormones

The influence of sex on pancreatic islet B cell susceptibility to streptozotocin was studied in mice given multiple low doses of streptozotocin. Male C3 D2 F1 mice developed a steadily increasing blood glucose level after a lag period of about 3 weeks, in contrast to females who were resistant. Spleen cells from streptozotocin treated female animals produced hyperglycaemia in total body irradiated