We present a new method to obtain long-term stable phase-conjugate feedback (pcf) with a photorefractive crystal for a mode-locked semiconductor laser. The phase-conjugate mirror is a barium titanate crystal in a self-pumped internal reflection configuration, and the laser is a visible, antireflection-coated AlGaInP diode. We describe a new dynamic writing procedure for growth of an index grating in the photorefractive crystal that leads to stable pcf and discuss the reasons for this stability, which is the major advantage of this method over previously reported ones. Using this superior method, we achieve stable mode-locked operation of the laser with pulse widths of ~30 ps and a timing jitter of less than 2 ps.
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http://dx.doi.org/10.1364/ol.20.000734 | DOI Listing |
J Cardiovasc Electrophysiol
January 2025
Cardiology Division, Geneva University Hospitals, Geneva, Switzerland.
Typical atrial flutter (AFL), defined as cavotricuspid isthmus (CTI)-dependent macro-re-entrant atrial tachycardia, often causes debilitating symptoms, and is associated with increased incidence of atrial fibrillation, stroke, heart failure, and death. Typical AFL occurs in patients with atrial remodeling and shares risk factors with atrial fibrillation. It is also common in patients with a history of prior heart surgery or catheter ablation.
View Article and Find Full Text PDFFront Transplant
December 2024
Laboratory of Respiratory Diseases and Thoracic Surgery (BREATHE), Department of CHROMETA, KU Leuven, Leuven, Belgium.
Long-term survival after lung transplantation is limited due to chronic lung allograft dysfunction (CLAD), which encompasses two main phenotypes: bronchiolitis obliterans syndrome (BOS) and restrictive allograft syndrome (RAS). Donor-derived cell-free DNA (dd-cfDNA) is a biomarker for (sub)clinical allograft injury and could be a tool for monitoring of lung allograft health across the (pre)clinical spectrum of CLAD. In this proof-of-concept study, we therefore assessed post-transplant plasma dd-cfDNA levels in 20 CLAD patients (11 BOS and 9 RAS) at three consecutive time points free from concurrent infection or acute rejection, during stable condition, preclinical CLAD, and established CLAD ( = 3 × 20 samples).
View Article and Find Full Text PDFPeerJ
January 2025
Department of Ecology and Conservation Biology, Texas A&M University, College Station, TX, United States of America.
Matrix population models are essential tools in conservation biology, offering key metrics to guide species management and conservation planning. However, the development of these models is often limited by insufficient life history data, particularly for non-charismatic species. This study addresses this gap by using life history data from FishBase and the FishLife R package, complemented by size-dependent natural mortality estimates, to parameterize age-structured matrix population models applicable to most fish species.
View Article and Find Full Text PDFObjective: To investigate the long-term impact of half-fluence photodynamic therapy (PDT) on chorioretinal architecture in chronic central serous chorioretinopathy (cCSCR) through novel choroidal vascularity index (CVI) versus previously established subfoveal choroidal thickness (SFCT).
Methods: This post-hoc analysis included prospectively collected swept-source optical coherence tomography (SS-OCT) images of a total of 29 cCSCR and fellow eyes (FE), acquired before, one and 12 months after PDT. CVI, total choroidal area (TCA), luminal area (LA) and stromal area (SA) were calculated using validated binarization technique.
Sci Rep
January 2025
Department of Clinical Nutrition, Yancheng Third People's Hospital, Affiliated Hospital 6 of Nantong University, Yancheng, 224001, People's Republic of China.
Previous studies reported that depressive symptoms were associated with a high risk of all-cause mortality. However, the effect of different long-term depressive symptom trajectory patterns on the risk of all-cause mortality has not been evaluated. Our research aimed to explore the association between different depressive symptom trajectories and the risk of all-cause mortality in Chinese adults.
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