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Revisiting the growth rate hypothesis : Towards a holistic stoichiometric understanding of growth

The growth rate hypothesis (GRH) posits that variation in organismal stoichiometry (C:P and N:P ratios) is driven by growth-dependent allocation of P to ribosomal RNA. The GRH has found broad but not uniform support in studies across diverse biota and habitats. We synthesise information on how and why the tripartite growth-RNA-P relationship predicted by the GRH may be uncoupled and outline paths

Vascular Aging and COVID-19

Vascular age is determined by functional and structural changes in the arterial wall. When measured by its proxy, pulse wave velocity, it has been shown to predict cardiovascular and total mortality. Disconcordance between chronological and vascular age might represent better or worse vascular health. Cell senescence is caused by oxidative stress and sustained cell replication. Senescent cells acq

Analysis of High-Performing Terahertz Quantum Cascade Lasers

Detailed simulations for terahertz quantum cascade lasers based on two-well designs are presented. We reproduce the maximal operation temperatures observed and attribute the degradation with temperature to the occupation of parasitic levels and thermal backfilling. Furthermore, we demonstrate that the current injection can be conveniently studied by using states, which combine energy selectivity a

Magnetic resonance and diffusion tensor imaging of the adolescent rabbit growth plate of the knee

Purpose: To assess the ability of MRI-DTI to evaluate growth plate morphology and activity compared with that of histomorphometry and micro-CT in rabbits. Methods: The hind limbs of female rabbits aged 16, 20, and 24 wk (n = 4 per age group) were studied using a 9.4T MRI scanner with a multi-gradient echo 3D sequence and DTI in 14 directions (b-value = 984 s/mm2). After MRI, the right and left hin

Imaging in gynecological disease (24) : clinical and ultrasound characteristics of ovarian mature cystic teratomas

Objective: To describe the clinical and ultrasound features of ovarian mature cystic teratomas (MCTs). Methods: This was a retrospective study. From the International Ovarian Tumor Analysis (IOTA) database, we identified patients with a histologically confirmed diagnosis of MCT who had undergone transvaginal ultrasound examination between 1999 and 2016 (IOTA phases 1, 2, 3 and 5) in one of five ce

Reversible Self-Assembled Monolayers with Tunable Surface Dynamics for Controlling Cell Adhesion Behavior

Cells adhering onto surfaces sense and respond to chemical and physical surface features. The control over cell adhesion behavior influences cell migration, proliferation, and differentiation, which are important considerations in biomaterial design for cell culture, tissue engineering, and regenerative medicine. Here, we report on a supramolecular-based approach to prepare reversible self-assembl

Mechanisms to control laser-plasma coupling in laser wakefield electron acceleration

Experimental results, supported by precise modeling, demonstrate optimization of a plasma-based injector with intermediate laser pulse energy (<1 J), corresponding to a normalized vector potential a0=2.15, using ionization injection in a tailored plasma density profile. An increase in electron bunch quality and energy is achieved experimentally with the extension of the density downramp at the pla

A quantitative synthesis of and predictive framework for studying winter warming effects in reptiles

Increases in temperature related to global warming have important implications for organismal fitness. For ectotherms inhabiting temperate regions, ‘winter warming’ is likely to be a key source of the thermal variation experienced in future years. Studies focusing on the active season predict largely positive responses to warming in the reptiles; however, overlooking potentially deleterious conseq

Design opportunities for future development of crisis communication technologies for marginalised groups – Co-designing with Swedish disability organisations

Purpose: The purpose is to firstly, provide an example of how voices of people with various disabilities (motor, visual, hearing, and neuropsychiatric impairments) can be listened to and involved in the initial phases of a co-design process (Discover, Define). Secondly, to present the outcome of the joint explorations as design opportunities pointing out directions for future development of crisis

Experimental and theoretical near-edge x-ray-absorption fine-structure studies of NO+

Experimental near-edge x-ray-absorption fine-structure (NEXAFS) spectra of the nitrosonium NO+ ion are presented and theoretically analyzed. While neutral NO has an open shell, the cation is a closed-shell species, which for NEXAFS leads to the simplicity of a closed-shell spectrum. Compared to neutral NO, the electrons in the cation experience a stronger Coulomb potential, which introduces a shif

Intensification of heat transfer behind the backward-facing step using tabs

The influence of tab size and location on the flow structure, distribution of pressures on the surface, and heat transfer in the separation region behind the backward-facing step at Reynolds number Re = 4000 was experimentally investigated. The effect of tabs on the distribution of the local pressure and heat transfer coefficients in the longitudinal and transversal directions was studied. The pre

Methodology and parameters to analyse daylighting and energy use in dense cities: A literature review

Low energy buildings are key to reduce global energy use. However, achieving low energy use and good daylight levels simultaneously in dense cities is challenging. This article reviews relevant studies dealing with energy use and daylighting in dense residential urban blocks located in Nordic climates. The literature review combines a systematic and a ‘snowball’ search approach. Findings indicate

Expansion of the Inguinal Adipose Tissue Depot Correlates With Systemic Insulin Resistance in C57BL/6J Mice

To accommodate surplus energy, the adipose tissue expands by increasing adipocyte size (hypertrophy) and number (hyperplasia). The presence of hypertrophic adipocytes is a key characteristic of adipose tissue dysfunction. High-fat diet (HFD) fed C57BL/6J mice are a commonly used model to study obesity and obesity-related complications. In the present study, we have characterized adipose plasticity

Individual Genetic Heterogeneity

Genetic variation has been widely covered in literature, however, not from the perspective of an individual in any species. Here, a synthesis of genetic concepts and variations relevant for individual genetic constitution is provided. All the different levels of genetic information and variation are covered, ranging from whether an organism is unmixed or hybrid, has variations in genome, chromosom

Apyrase decreases phage induction and Shiga toxin release from E. coli O157:H7 and has a protective effect during infection

Shiga toxin (Stx)-producing enterohemorrhagic Escherichia coli (EHEC) cause gastrointestinal infection and, in severe cases, hemolytic uremic syndrome which may lead to death. There is, to-date, no therapy for this infection. Stx induces ATP release from host cells and ATP signaling mediates its cytotoxic effects. Apyrase cleaves and neutralizes ATP and its effect on Stx and EHEC infection was the

Organizational and patient-level predictors for attaining key risk factor targets in cardiac rehabilitation after myocardial infarction : The Perfect-CR study

Background: Benefits of cardiac rehabilitation (CR) programme components on attaining risk factor targets post-myocardial infarction (MI) and their predictive strength relative to patient characteristics remain unclear. We aimed to identify organizational and patient-level predictors of risk factor target attainment at one-year post-MI. Methods: In this observational study data on CR organization

Obesity is associated with coronary artery stenosis independently of metabolic risk factors : The population-based SCAPIS study

Background and aims: Previous studies reported divergent results on whether metabolically healthy obesity is associated with increased coronary artery calcium and carotid plaques. We investigated this in a cross-sectional fashion in a large, well-defined, middle-aged population using coronary CT angiography (CCTA) and carotid ultrasound. Methods: In the SCAPIS study (50–65 years, 51% female), CCTA

Optical cavity-mediated exciton dynamics in photosynthetic light harvesting 2 complexes

Strong light-matter interaction leads to the formation of hybrid polariton states and alters the photophysical dynamics of organic materials and biological systems without modifying their chemical structure. Here, we experimentally investigated a well-known photosynthetic protein, light harvesting 2 complexes (LH2) from purple bacteria under strong coupling with the light mode of a Fabry-Perot opt

Effects of parasitic freshwater mussels on their host fishes : a review

Freshwater mussels in the order Unionida are highly adapted to parasitize fish for the primary purpose of dispersal. The parasitic larval stage affixes itself to the gills or fins of the host where it becomes encysted in the tissue, eventually excysting to develop into a free-living adult. Research on the parasitic interactions between unionids and their host fishes has garnered attention recently