Rapid regulation of excitation energy in two pennate diatoms from contrasting light climates.

Non-photochemical quenching (NPQ) is a fast acting photoprotective response to high light stress triggered by over excitation of photosystem II. The mechanism for NPQ in the globally important diatom algae has been principally attributed to a xanthophyll cycle, analogous to the well-described qE quenching of higher plants. This study compared the short-term NPQ responses in two pennate, benthic diatom species cultured under identical conditions but which originate from unique light climates.

Remodelling of the bovine placenta: Comprehensive morphological and histomorphological characterization at the late embryonic and early accelerated fetal growth stages.

Introduction: Placental function impacts growth and development with lifelong consequences for performance and health. We provide novel insights into placental development in bovine, an important agricultural species and biomedical model.

Methods: Concepti with defined genetics and sex were recovered from nulliparous dams managed under standardized conditions to study placental gross morphological and histomorphological parameters at the late embryo (Day48) and early accelerated fetal growth (Day153) stages.

Septic Pulmonary Embolism Caused by Infected Pacemaker Leads After Replacement of a Cardiac Resynchronization Therapy Device.

BACKGROUND Cardiac resynchronization therapy (CRT) has been demonstrated to reduce morbidity and mortality in patients with advanced, drug-refractory heart failure. Procedure-related mortality is less than 1% in larger studies. Approximately10% of CRT patients have to undergo surgical revision because of infections, dislocations, or unacceptable electrical behavior manifested as high threshold, unstable sensing, or unwanted phrenic nerve stimulation.

EMG correlations of edentulous patients with implant overdentures and fixed dental prostheses compared to conventional complete dentures and dentates: a systematic review and meta-analysis.

Objectives: The goal of this meta-analysis was to evaluate how muscular activity, measured by electromyography (EMG), differs among edentulous patients treated with a complete denture (CD), removable implant overdentures (IO), implant-retained fixed dental prostheses (IFDP), and dentates. The differences during clenching and chewing were of particular interest.

Materials And Methods: An electronic literature review was carried out on MEDLINE (Pubmed) and the Cochrane Library covering the period January 1980 through September 2013.

Diverse mechanisms for photoprotection in photosynthesis. Dynamic regulation of photosystem II excitation in response to rapid environmental change.

Photosystem II (PSII) of photosynthesis catalyzes one of the most challenging reactions in nature, the light driven oxidation of water and release of molecular oxygen. PSII couples the sequential four step oxidation of water and two step reduction of plastoquinone to single photon photochemistry with charge accumulation centers on both its electron donor and acceptor sides. Photon capture, excitation energy transfer, and trapping occur on a much faster time scale than the subsequent electron transfer and charge accumulation steps.