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Is timing of reproduction according to temperature sums an optimal strategy?

Temperature sums are widely used to predict the seasonal timing of yearly recurring biological events, such as flowering, budburst, and hatching. We use a classic energy allocation model for annual plants to compare a strategy for reproductive timing that follows a temperature sum rule (TSR) with a strategy that follows an optimal control rule (OCR) maximizing reproductive output. We show that the

Leaky Optoelectrical Fiber for Optogenetic Stimulation and Electrochemical Detection of Dopamine Exocytosis from Human Dopaminergic Neurons

In Parkinson's disease, the degeneration of dopaminergic neurons in substantia nigra leads to a decrease in the physiological levels of dopamine in striatum. The existing dopaminergic therapies effectively alleviate the symptoms, albeit they do not revert the disease progression and result in significant adverse effects. Transplanting dopaminergic neurons derived from stem cells could restore dopa

Analysis of early-flowering genes at barley chromosome 2H expands the repertoire of mutant alleles at the Mat-c locus

Key message: Analyses of barley mat-c loss of function mutants reveal deletions, splice-site mutations and nonsynonymous substitutions in a key gene regulating early flowering. Abstract: Optimal timing of flowering is critical for reproductive success and crop yield improvement. Several major quantitative trait loci for flowering time variation have been identified in barley. In the present study,

Utgör livsmedelspriser en barriär mot en hälsosam kost?

Förekomsten av kostrelaterade sjukdomar ökar, framför allt i grupper som lever under ekonomisk knapphet. Detta förklaras ofta med det höga priset på eller den höga prisökningstakten för hälsosamma livsmedel. De samhällsekonomiska implikationerna av en sådan förklaring är omfattande eftersom de motiverar mer omfattande omfördelning eller prismanipulation som lösning på hälsoproblemen. Detta bidrag

Stockholmare, flytta dit bostäderna finns

På samma sätt som det är naturligt för ungdomar från bruksorter att flytta till Stockholm bör Stockholmsungdomar ställa in sig på att flytta ut från stan, skriver Ingemar Bengtsson, universitetslektor i fastighetsvetenskap vid Lunds universitet.

Droplet Breakup in High-Pressure Homogenizers

In this chapter, a detailed review of the current understanding of thephysical processes of droplet breakup in a high-pressure homogenizer (HPH) is presented,covering breakup mechanisms by laminar shear in the gap inlet and its boundarylayers, by local turbulence in the gap exit jet, and by cavitation. Experimentalevidence of the effects of homogenization pressure, Thoma number, dispersed andcontiIn this chapter, a detailed review of the current understanding of the physical processes of droplet breakup in a high-pressure homogenizer (HPH) is presented, covering breakup mechanisms by laminar shear in the gap inlet and its boundary layers, by local turbulence in the gap exit jet, and by cavitation. Experimental evidence of the effects of homogenization pressure, Thoma number, dispersed and

Vad ska vi med föreläsningar till?

Föreläsningen är en märklig undervisningsform. Samtidigt som den är den vanligast förekommandemetoden, är den också den mest föraktade. Det finns gott om högskolepedagogisklitteratur som förklarar varför föreläsningen är olämplig för att stimulera lärande. Ändåfortsätter vi föreläsa. Det kan tyckas motsägelsefullt.Denna reflektion vänder på frågan och letar efter föreläsningens fördelar. Utifrån t

Quantitative T-wave morphology assessment from surface ECG is linked with cardiac events risk in genotype-positive KCNH2 mutation carriers with normal QTc values

Introduction: Long QT syndrome (LQTS) mutation carriers have elevated the risk of cardiac events even in the absence of QTc prolongation; however, mutation penetrance in patients with normal QTc may be reflected in abnormal T-wave shape, particularly in KCNH2 mutation carriers. We aimed to assess whether the magnitude of a three-dimensional T-wave vector (TwVM) will identify KCNH2-mutation carrier

Construct validity of a revised version of the Occupational Balance Questionnaire

Background: Occupational balance is fundamental to occupational therapy and occupational science. Therefore, the Occupational Balance Questionnaire (OBQ) was developed and has previously been found psychometrically valid according to classical test theory. Aim: To investigate the internal construct validity of the OBQ using Rasch measurement theory. Material and methods: Data from two general popu

Parametric study and optimization on heat transfer and flow characteristics in a rectangular channel with longitudinal vortex generators

In this study, effects of various geometrical parameters of a new winglet longitudinal vortex generator (LVG) on heat transfer and flow characteristics in a rectangular channel were investigated by a numerical method, and the influence of various parameters was analyzed. A comparative study of effects of elliptical pole parameters, the thickness, the length, the height, the attack angle, the trans

All-polyethylene versus metal-backed posterior stabilized total knee arthroplasty : similar 2-year results of a randomized radiostereometric analysis study

Background and purpose — The all-polyethylene tibial (APT) component, introduced in the early 1970s, was surpassed by metal-backed tibial (MBT) trays as the first choice for total knee arthroplasty (TKA). With improved polyethylene, the modern APT components can reduce costs, and have shown equivalent results in survivorship and early migration of the cruciate-retaining and cruciate-stabilizing de

Anisotropic Hollow Microgels That Can Adapt Their Size, Shape, and Softness

The development of soft anisotropic building blocks is of great interest for various applications in soft matter. Furthermore, such systems would be important model systems for ordering phenomena in fundamental soft matter science. In this work, we address the challenge of creating hollow and anisotropically shaped thermoresponsive microgels, polymeric networks with a solvent filled cavity in thei

Communities of oil palm flower-visiting insects : Investigating the covariation of Elaeidobius kamerunicus and other dominant species

Insects visit flowers not only to forage for nectar or pollen but also to search for hosts or prey, and to look for suitable habitats for breeding sites. In oil palm flowers, it has been documented that not all flower-visiting insects are pollinators, but some insects are recognized as predators, parasitoids or saprophages, which may affect the abundance and persistence of the weevil pollinating o

Kallikrein markers performance in pretreatment blood to predict early prostate cancer recurrence and metastasis after radical prostatectomy among very high-risk men

Background: To assess whether a prespecified statistical model based on the four kallikrein markers measured in blood—total, free, and intact prostate-specific antigen (PSA), together with human kallikrein-related peptidase 2 (hK2)—or any individual marker measured in pretreatment serum were associated with biochemical recurrence-free (BCR) or metastasis-free survival after radical prostatectomy (

Lung function and pulmonary vascular resistance are not associated in 6-year-old children born extremely preterm

Aim: Children born preterm are at increased risk of reduced lung function. The aim was to test whether lung function was associated with pulmonary vascular resistance. Methods: Participants were recruited from a population-based cohort born in 2004-2007. Lung function was assessed with spirometry after administration of a beta2-agonist. Forced vital capacity (FVC) and forced expiratory volume in o

Mean muscle attenuation correlates with severe acute pancreatitis unlike visceral adipose tissue and subcutaneous adipose tissue

Background: Acute pancreatitis (AP) is a frequent disorder with considerable morbidity and mortality. Obesity has previously been reported to influence disease severity. Objective: The aim of this study was to investigate the association of adipose and muscle parameters with the severity grade of AP. Methods: In total 454 patients were recruited. The first contrast-enhanced computed tomography of

Mortality in rheumatoid arthritis patients with disease onset in the 1980s

OBJECTIVE: Several previous studies have shown increased mortality in rheumatoid arthritis (RA) patients. This study investigated if this was true also for patients with disease onset in the 1980s.PATIENTS AND METHODS: The study group comprised 183 patients (67 men and 116 women) with definite RA participating in an ongoing prospective study. Mean age at onset of disease was 51 years, and mean dur

Thyroid Hormones in the Brain and Their Impact in Recovery Mechanisms After Stroke

Thyroid hormones are of fundamental importance for brain development and essential factors to warrant brain functions throughout life. Their actions are mediated by binding to specific intracellular and membranous receptors regulating genomic and non-genomic mechanisms in neurons and populations of glial cells, respectively. Among others, mechanisms include the regulation of neuronal plasticity pr

Non-invasive imaging methodologies for assessment of radiation damage to bone marrow and kidneys from peptide receptor radionuclide therapy. : -

Background/Aims: Peptide receptor radionuclide therapy (PRRT) is becoming clinical routine for management of Neuroendocrine Tumours. The number of PRRT cycles are correlated with treatment effect but theoretically limited by off-target radiation damage to kidneys and bone marrow. New imaging biomarkers for assessment of PRRT tissue damage would enable evaluation of novel renal and bone marrow protBackground/Aims: Peptide receptor radionuclide therapy (PRRT) is becoming clinical routine for management of neuroendocrine tumours. The number of PRRT cycles is correlated with treatment effect but theoretically limited by off-target radiation damage to kidneys and bone marrow. New imaging biomarkers for assessment of PRRT tissue damage would enable evaluation of novel renal and bone marrow prote