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More on how and why: cause and effect in biology revisited

In 1961, Ernst Mayr published a highly influential article on the nature of causation in biology, in which he distinguished between proximate and ultimate causes. Mayr argued that proximate causes (e.g. physiological factors) and ultimate causes (e.g. natural selection) addressed distinct 'how' and 'why' questions and were not competing alternatives. That distinction retains explanatory value toda

Comorbidities and Mortality in Persons With Schizophrenia: A Swedish National Cohort Study

Objective: Schizophrenia is associated with premature mortality, but the specific causes and pathways are unclear. The authors used outpatient and inpatient data for a national population to examine the association between schizophrenia and mortality and comorbidities. Method: This was a national cohort study of 6,097,834 Swedish adults, including 8,277 with schizophrenia, followed for 7 years (20

High Turnover Catalase Activity of a Mixed-Valence (MnMnIII)-Mn-II Complex with Terminal Carboxylate Donors

The neutral dimanganese(II,III) complex [Mn-2(BCPMP)-(OAc)(2)] [1; BCPMP3- = 2,6-bis({(carboxymethyl)[(1-pyridyl)-methyl] amino} methyl)-4-methylphenolato] has been synthesized and characterized. The complex contains two terminal carboxylate donors. Complex 1 was found to be an effective catalyst for the disproportionation of H2O2 with high catalytic rate and a turnover number of 7500, the highest

Toward standardization of carbohydrate-deficient transferrin (CDT) measurements: III. Performance of native serum and serum spiked with disialotransferrin proves that harmonization of CDT assays is possible

Carbohydrate-deficient transferrin (CDT) is a generic term that refers to the transferrin glycoforms whose concentration in blood is temporarily increased by sustained alcohol consumption. Due to high clinical specificity, CDT was proposed as a biomarker of heavy alcohol use and has been available for about 20 years. A number of methods have been developed for CDT measurement based on different an

Protein biomarkers for the prediction of cardiovascular disease in type 2 diabetes

Aims/hypothesis We selected the most informative protein biomarkers for the prediction of incident cardiovascular disease (CVD) in people with type 2 diabetes. Methods In this nested case-control study we measured 42 candidate CVD biomarkers in 1,123 incident CVD cases and 1,187 controls with type 2 diabetes selected from five European centres. Combinations of biomarkers were selected using cross-

The B-matrix harbors significant and sex-specific constraints on the evolution of multicharacter sexual dimorphism.

The extent to which sexual dimorphism can evolve within a population depends on an interaction between sexually divergent selection and constraints imposed by a genetic architecture that is shared between males and females. The degree of constraint within a population is normally inferred from the intersexual genetic correlation, r(mf) . However, such bivariate correlations ignore the potential co

Regulated protein aggregation, a mechanism to control the activity of the ClpXP adaptor protein YjbH.

Bacteria use stress response pathways to activate diverse target genes to react to a variety of stresses. The Bacillus subtilis Spx protein is a global transcriptional regulator that controls expression of more than 140 genes and operons in response to thiol-specific oxidative stress. Under non-stress conditions the concentration of Spx is kept low by proteolysis catalyzed by the ClpXP complex. Sp

Signatures of mutational processes in human cancer

All cancers are caused by somatic mutations; however, understanding of the biological processes generating these mutations is limited. The catalogue of somatic mutations from a cancer genome bears the signatures of the mutational processes that have been operative. Here we analysed 4,938,362 mutations from 7,042 cancers and extracted more than 20 distinct mutational signatures. Some are present in

Interface fracture toughness of a multi-directional woven composite

The aim of this investigation is to measure the interface fracture toughness of a woven composite. For this purpose, double cantilever beam (DCB) specimens are tested to measure the load as the delamination grows. The specimen is composed of 15 layers of a carbon-epoxy, balanced weave with alternate layers containing fibers in the directions and the directions. A thin piece of Teflon is placed bet

Heat transfer and pressure drop in a smooth and ribbed turn region of a two-pass channel

In the present study, the heat transfer and pressure drop in the turn region of a two-pass channel have been investigated experimentally. The liquid crystal thermography method is utilized to measure local heat transfer rates. Eight cases were tested, including one smooth, and seven different rib-roughened turn surfaces. The tested Reynolds numbers are 20,000 and 26,000, respectively. Results indi

Global, regional, and national age-sex specific all-cause and cause-specific mortality for 240 causes of death, 1990-2013: a systematic analysis for the Global Burden of Disease Study 2013

Background Up-to-date evidence on levels and trends for age-sex-specifi c all-cause and cause-specifi c mortality is essential for the formation of global, regional, and national health policies. In the Global Burden of Disease Study 2013 (GBD 2013) we estimated yearly deaths for 188 countries between 1990, and 2013. We used the results to assess whether there is epidemiological convergence across

Comparison of two commonly used reference materials for exercise bicycle tests with a Swedish clinical database of patients with normal outcome

Background: Reference values for working capacity, blood pressure, heart rate, perceived exertion, etc. during bicycle exercise tests have been sought after for many years. This is because earlier commonly used reference values for physical work capacity have been either too low or too high when compared to the clinical experience of several Swedish departments of clinical physiology. The aim of t

Evaporative Cooling: effective latent heat of evaporation in relation to evaporation distance from the skin

Calculation of evaporative heat loss is essential to heat balance calculations. Despite recognition that the value for latent heat of evaporation, used in these calculations, may not always reflect the real cooling benefit to the body, only limited quantitative data on this is available which has found little use in recent literature. In this experiment a thermal manikin (MTNW, Seattle) was used t

The jazz storyteller: Improvisers’ perspectives on music and narrative

The term ‘storytelling’ has a long history of prominence in descriptive and prescriptive talk about jazz improvisation. The main aim of this article is to point out that the ways in which jazz musicians themselves employ the ‘storytelling’ metaphor with reference to jazz improvisation display several important perspectives on perennial and fundamental prob- lems in the field of musical narrativity

Effect of vertebral fractures on function, quality of life and hospitalisation the AGES-Reykjavik study

Objective: assess the effect of clinical vertebral and other osteoporotic fractures on function and the subsequent risk of hospitalisation. Design: individuals from the prospective population-based cohort study Age, Gene/Environment Susceptibility (AGES)-Reykjavik study were examined between 2002 and 2006 and followed up for 5.4 years. Subjects: a total of 5,764 individuals, 57.7% women, born 1907

Neural coding underlying the cue preference for celestial orientation

Diurnal and nocturnal African dung beetles use celestial cues, such as the sun, the moon, and the polarization pattern, to roll dung balls along straight paths across the savanna. Although nocturnal beetles move in the same manner through the same environment as their diurnal relatives, they do so when light conditions are at least 1 million-fold dimmer. Here, we show, for the first time to our kn

ApoA-I Milano stimulates lipolysis in adipose cells independently of cAMP/PKA activation.

ApoA-I, the main protein component of high-density lipoprotein (HDL), is suggested to be involved in metabolic homeostasis. We examined the effects of Milano, a naturally occurring ApoA-I variant, about which little mechanistic information is available. Remarkably, high fat-fed mice treated with Milano displayed a rapid weight loss greater than ApoA-I WT treated mice, and a significantly reduced a

Sterically stabilized colloids with tunable repulsions

When studying tunable electrostatic repulsions in aqueous suspensions of charged colloids, irreversible colloid aggregation or gelation may occur at high salt concentrations. For many commonly used synthetic colloids, such as polystyrene and silica particles, the reason for coagulation is the presence of unbalanced, strongly attractive, and short-ranged van der Waals (VDW) forces. Here, we present

Upper extremity nerve entrapments: the axillary and radial nerves - clinical diagnosis and surgical treatment.

Non-traumatic pain in the shoulder, arm and hand (brachialgia) is a common complaint in the field of musculoskeletal disorders, where nerve entrapment constitutes a possible cause. The effect of nerve compression is dose-dependent; hence a low-level compression will only result in decreased endoneurial circulation, neural edema and a Seddon's grade-IV weakness, but won't be revealed in nerve condu

The Danish national return-to-work program - aims, content, and design of the process and effect evaluation

The Danish national return-to-work (RTW) program aims to improve the management of municipal sickness benefit in Denmark. A study is currently ongoing to evaluate the RTW program. The purpose of this article is to describe the study protocol. The program includes 21 municipalities encompassing approximately 19 500 working-age adults on long-term sickness absence, regardless of reason for sickness