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The effects of resonator coupling on the linewidth enhancement factor of semiconductor lasers is studied. Since in-phase coupling has adverse effects on laser performance, it is important to limit them to ensure the reliable operation of laser-based optical communications systems. The phase of the laser resonator's coupling constant and the carrier scattering parameter were analyzed and their nonlinear effects were evaluated. It was found that the structure's level of gain coupling has significant effects on intensity of in-phase coupling.

Introduction: Prevalence of obesity and associated diseases, including type 2 diabetes mellitus, dyslipidaemia and non‐alcoholic fatty liver disease (NAFLD), are increasing. Underlying mechanisms, especially in humans, are unclear. Bariatric surgery provides the unique opportunity to obtain biopsies and portal vein blood‐samples. Methods: The BARIA Study aims to assess how microbiota and their metabolites affect transcription in key tissues and clinical outcome in obese subjects and how baseline anthropometric and metabolic characteristics determine weight loss and glucose homeostasis after bariatric surgery. We phenotype patients undergoing bariatric surgery (predominantly laparoscopic Roux‐en‐Y gastric bypass), before weight loss, with biometrics, dietary and psychological questionnaires, mixed meal test (MMT) and collect fecal‐samples and intra‐operative biopsies from liver, adipose tissues and jejunum. We aim to include 1500 patients. A subset (approximately 25%) will undergo intra‐operative portal vein blood‐sampling. Fecal‐samples are analyzed with shotgun metagenomics and targeted metabolomics, fasted and postprandial plasma‐samples are subjected to metabolomics, and RNA is extracted from the tissues for RNAseq‐analyses. Data will be integrated using state‐of‐the‐art neuronal networks and metabolic modeling. Patient follow‐up will be ten years. Results: Preoperative MMT of 170 patients were analysed and clear differences were observed in glucose homeostasis between individuals. Repeated MMT in 10 patients showed satisfactory intra‐individual reproducibility, with differences in plasma glucose, insulin and triglycerides within 20% of the mean difference. Conclusion: The BARIA study can add more understanding in how gut‐microbiota affect metabolism, especially with regard to obesity, glucose metabolism and NAFLD. Identification of key factors may provide diagnostic and therapeutic leads to control the obesity‐associated disease epidemic. [ABSTRACT FROM AUTHOR]

The influence of a momentum gap on the stability of a semiconductor laser was investigated. The results showed that a gap formed by second-order coupling will not produce a coupling coefficient with a strong dependence on carrier density. Incorporation of such a carrier density dependence into a second order structure could significantly enhance laser stability.

Pharmaceuticals and per- and polyfluoroalkyl substances (PFAS) are persistent organic micropollutants (OMPs) posing environmental and health risks due to their bioaccumulative nature and potential toxicity. These OMPs spread to the environment due to the extensive use in today's society. Conventional wastewater treatment plants (WWTPs) are not designed to effectively remove these contaminants, making WWTPs an important pathway, especially for pharmaceuticals, to the aquatic environment. This study investigates the efficiency of combining granular activated carbon (GAC) and anion exchange (AIX) for the removal of OMPs from wastewater. While GAC is a well-established method for removal of pharmaceuticals and AIX for PFAS removal, the combination of GAC and AIX for treating municipal wastewater has not been evaluated before. This research therefore focuses on long-term trials assessing the removal efficiencies of GAC and AIX filters in both bench-scale and pilot-scale setups at Kungsängsverket WWTP in Uppsala, Sweden. The combination of GAC and AIX filters showed over 90 % removal efficiency for pharmaceuticals such as diclofenac up to 20,000 treated empty bed volumes (EBV). PFAS removal was primarily achieved by AIX after the initial 5000 EBV by GAC, highlighting the complementary roles of the two technologies. The findings contribute with new insights utilizing GAC and AIX as a combined treatment approach for reducing OMPs in municipal wastewater, contributing to improved environmental and public health outcomes., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2025 The Authors. Published by Elsevier B.V. All rights reserved.)

Foot drop (FD) can be caused by a variety of diseases and injuries. FD leads to walking difficulties and reduced balance which also can lead to a higher risk of falling. Patient with a stroke often have an equinovarus deformity of the foot together with the DF. There is a need to optimize and standardize the treatment for patients with FD across different medical specialities. Surgical interventions, with goals of producing a balanced functional foot, have been shown to improve the function and quality of life and decrease the use of braces and walking aids in patients with FD after a CVI. In Sweden data regarding FD surgery is collected in the National Quality Registry for Foot and Ankle Surgery (Riksfot), but there is also an ongoing multicentre study, investigating the patient-reported and functional results of surgery due to FD caused by a CVI.

Alzheimer's disease (AD) is strongly linked to amyloid depositions of the Aβ peptide (Aβ). The lipid-binding protein apolipoprotein E (ApoE) has been found to interfere with Aβ amyloid formation and to exert a strong clinical impact to the pathology of AD. The APOE gene exists in three allelic isoforms represented by APOE ε2, APOE ε3, and APOE ε4. Carriers of the APOE ε4 variant display a gene dose-dependent increased risk of developing the disease. Aβ amyloids are formed via a nucleation-dependent mechanism where free monomers are added onto a nucleus in a template-dependent manner. Using a combination of surface plasmon resonance and thioflavin-T assays, we here show that ApoE can target the process of fibril elongation and that its interference effectively prevents amyloid maturation. We expose a complex equilibrium where the concentration of ApoE, Aβ monomers, and the amount of already formed Aβ fibrils will affect the relative proportion and formation rate of mature amyloids versus alternative assemblies. The result illustrates a mechanism which may affect both the clearance rate of Aβ assemblies in vivo and the population of cytotoxic Aβ assemblies., (© 2019 Federation of European Biochemical Societies.)

Due to the essential roles of glutamate, detection and response to a large range of extracellular concentrations of this excitatory amino acid are necessary for the fine-tuning of brain functions. Metabotropic glutamate receptors (mGluRs) are implicated in shaping the activity of many synapses in the central nervous system. Among the eight mGluR subtypes, there is increasing interest in studying the mGlu 3 receptor which has recently been linked to various diseases, including psychiatric disorders. This receptor displays striking functional properties, with a high and, often, full basal activity, making its study elusive in heterologous systems. Here, we demonstrate that Cl - ions exert strong positive allosteric modulation of glutamate on the mGlu 3 receptor. We have also identified the molecular and structural determinants lying behind this allostery: a unique interactive "chloride-lock" network. Indeed, Cl - ions dramatically stabilize the glutamate-induced active state of the extracellular domain of the mGlu 3 receptor. Thus, the mGlu 3 receptors' large basal activity does not correspond to a constitutive activity in absence of agonist. Instead, it results mostly from a Cl - mediated amplified response to low ambient glutamate concentrations, such as those measured in cell media. This strong interaction between glutamate and Cl - ions allows the mGlu 3 receptor to sense and efficiently react to sub-micromolar concentrations of glutamate, making it the most sensitive member of mGluR family., (Copyright © 2018. Published by Elsevier Ltd.)

Our lack of full understanding of transport and sequestration of the heterologous products currently limit metabolic engineering in plants for the production of high value terpenes. For instance, although all genes of the artemisinin/arteannuin B (AN/AB) biosynthesis pathway (AN-PW) from Artemisia annua have been identified, ectopic expression of these genes in Nicotiana benthamiana yielded mostly glycosylated pathway intermediates and only very little free (dihydro)artemisinic acid [(DH)AA]. Here we demonstrate that Lipid Transfer Protein 3 (AaLTP3) and the transporter Pleiotropic Drug Resistance 2 (AaPDR2) from A. annua enhance accumulation of (DH)AA in the apoplast of N. benthamiana leaves. Analysis of apoplast and cell content and apoplast exclusion assays show that AaLTP3 and AaPDR2 prevent reflux of (DH)AA from the apoplast back into the cells and enhances overall flux through the pathway. Moreover, AaLTP3 is stabilized in the presence of AN-PW activity and co-expression of AN-PW+AaLTP3+AaPDR2 genes yielded AN and AB in necrotic N. benthamiana leaves at 13 days post-agroinfiltration. This newly discovered function of LTPs opens up new possibilities for the engineering of biosynthesis pathways of high value terpenes in heterologous expression systems., (Copyright © 2016 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.)

Efficient cell-to-cell communication relies on the accurate signalling of cell surface receptors. Understanding the molecular bases of their activation requires the characterization of the dynamic equilibrium between active and resting states. Here, we monitor, using single-molecule Förster resonance energy transfer, the kinetics of the reorientation of the extracellular ligand-binding domain of the metabotropic glutamate receptor (mGluR), a class C G-protein-coupled receptor. We demonstrate that most receptors oscillate between a resting- and an active-conformation on a sub-millisecond timescale. Interestingly, we demonstrate that differences in agonist efficacies stem from differing abilities to shift the conformational equilibrium towards the fully active state, rather than from the stabilization of alternative static conformations, which further highlights the dynamic nature of mGluRs and revises our understanding of receptor activation and allosteric modulation.

Objective: Adrenal adenomas discovered as incidentalomas may secrete cortisol and cause subclinical hypercortisolism. This cortisol secretion is considered to be autonomous. The aim was to investigate whether cortisol secretion by adenomas is responsive to ACTH., Design: Descriptive retrospective study of consecutive patients., Patients: Eighty patients found to have adrenal incidentalomas during 2008 and 2009 at our hospital were examined, and 50 patients with a unilateral adenoma were included in the study., Measurements: Cortisol and ACTH were measured at baseline and using 1-mg overnight dexamethasone suppression test (DST). The cortisol response to ACTH was calculated using the expression: (cortisolbasal -cortisolDST )/(ACTHbasal -ACTHDST )., Results: The patients were divided into three groups according to their basal ACTH: ≥3·0 pm (29 patients), 2·0-2·9 pm (9 patients) and <2·0 pm (12 patients). Cortisol at DST was similar in the three groups: 30, 46 and 43 nm (P = 0·10). The cortisol response to ACTH increased stepwise between the groups: 98, 172 and 249 nm/pm (P = 0·000, undetectable ACTH was set to 0 pm). Basal ACTH was negatively correlated with the size of the adenoma and positively correlated with the attenuation of the adenoma at unenhanced CT (P = 0·03 and P = 0·04, respectively)., Conclusions: Patients with adrenal adenomas and low basal ACTH show increased cortisol response to ACTH, and the adenomas seem to be the source of the increased cortisol secretion. The increased response to ACTH could be a pathogenic factor in metabolic complications of subclinical hypercortisolism. The cortisol response to ACTH may therefore be a useful measure of subclinical hypercortisolism., (© 2013 John Wiley & Sons Ltd.)

Pulsed Interleaved Excitation (PIE) improves fluorescence cross-correlation spectroscopy (FCCS) and single pair Förster Resonance Energy Transfer (spFRET) measurements, by correlating each detected photon to the excitation source that generated it. It relies on the interleaving of two picosecond laser sources and time correlated single photon counting (TCSPC) detection. Here, we present an optical configuration based on a commercial supercontinuum laser, which generates multicoulour interleaved picosecond pulses with arbitrary spacing and wavelengths within the visible spectrum. This simple, yet robust configuration can be used as a versatile source for PIE experiments, as an alternative to an array of picosecond lasers and drivers.

The aim of this project was to evaluate the effect of fixation on plant material prior to Laser Microdissection and Pressure Catapulting (LMPC) and to identify an appropriate method for preserving good RNA quality after cell isolation. Therefore, flower buds from Artemisia annua L. were exposed to either the fixative formaldehyde or a non-fixative buffer prior to cell isolation by LMPC. Proteinase K was used after cell isolation from fixed plant tissue, in an attempt to improve the RNA yield. The ability to detect gene expression using real-time quantitative PCR with or without previous amplification of RNA from cells isolated by LMPC was also evaluated. Conclusively, we describe a new technique, without fixation, enabling complete isolation of intact glandular secretory trichomes and specific single trichome cells of A. annua. This method is based on LMPC and preserves good RNA quality for subsequent RNA expression studies of both whole trichomes, apical and sub-apical cells from trichomes of A. annua. Using this method, expression of genes of terpene metabolism was studied by real-time quantitative PCR. Expression of genes involved in artemisinin biosynthesis was observed in both apical and sub-apical cells., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

Background: Recently, Artemisia annua L. (annual or sweet wormwood) has received increasing attention due to the fact that the plant produces the sesquiterpenoid endoperoxide artemisinin, which today is widely used for treatment of malaria. The plant produces relatively small amounts of artemisinin and a worldwide shortage of the drug has led to intense research in order to increase the yield of artemisinin. In order to improve our understanding of terpene metabolism in the plant and to evaluate the competition for precursors, which may influence the yield of artemisinin, we have used qPCR to estimate the expression of 14 genes of terpene metabolism in different tissues., Results: The four genes of the artemisinin biosynthetic pathway (amorpha-4,11-diene synthase, amorphadiene-12-hydroxylase, artemisinic aldehyde ∆11(13) reductase and aldehyde dehydrogenase 1) showed remarkably higher expression (between ~40- to ~500-fold) in flower buds and young leaves compared to other tissues (old leaves, stems, roots, hairy root cultures). Further, dihydroartemisinic aldehyde reductase showed a very high expression only in hairy root cultures. Germacrene A and caryophyllene synthase were mostly expressed in young leaves and flower buds while epi-cedrol synthase was highly expressed in old leaves. 3-Hydroxy-3-methyl-glutaryl coenzyme A reductase exhibited lower expression in old leaves compared to other tissues. Farnesyldiphosphate synthase, squalene synthase, and 1-deoxy-D-xylulose-5-phosphate reductoisomerase showed only modest variation in expression in the different tissues, while expression of 1-deoxy-D-xylulose-5-phosphate synthase was 7-8-fold higher in flower buds and young leaves compared to old leaves., Conclusions: Four genes of artemisinin biosynthesis were highly expressed in flower buds and young leaves (tissues showing a high density of glandular trichomes). The expression of dihydroartemisinic aldehyde reductase has been suggested to have a negative effect on artemisinin production through reduction of dihydroartemisinic aldehyde to dihydroartemisinic alcohol. However, our results show that this enzyme is expressed only at low levels in tissues producing artemisinin and consequently its effect on artemisinin production may be limited. Finally, squalene synthase but not other sesquiterpene synthases appears to be a significant competitor for farnesyl diphosphate in artemisinin-producing tissues.