Scalable all-fiber coherent beam combination using digital control.

This paper describes a filled-aperture coherent beam combining (CBC) system based on locking of optical coherence via single-detector electronic-frequency tagging (LOCSET). The sensing and control architecture is implemented using a field-programmable gate array and high-bandwidth electro-optic phase modulators. The all-fiber optical configuration consists of a narrow linewidth 1560 nm seed laser separated into three channels, each containing 7 W erbium-doped fiber amplifiers. The system was demonstrated experimentally, achieving a total stabilized output power of 20 W, a combination efficiency greater than 95%, and an output RMS phase stability of λ/493. As this architecture employs an entirely digital sensing and control scheme based on LOCSET, it presents a highly scalable and cost-effective solution for CBC that is wavelength agnostic and can support an arbitrarily large number of channels.

Prescribing and medical non-adherence after myocardial infarction: qualitative interviews with general practitioners in Germany.

BACKGROUND: An increasing prevalence of having survived a myocardial infarction increases the importance of medical secondary prevention. Although preventive medication reduces mortality, prescribing and adherence are known to be frequently insufficient. General practitioners are the most important prescriber. However, their perspective on prescribing and medical non-adherence following myocardial infarction has not yet been explored. Thus, the aim of this study was to explore the general practitioners' perspective on long-term care after myocardial infarction focussing on medical prevention. METHODS: In this qualitative interview study we conducted episodic interviews with sixteen general practitioners from rural and urban surgeries in Germany. Framework analysis with focus on general practitioners' prescribing and patients' non-adherence was performed. RESULTS: Almost all general practitioners reported following guidelines for myocardial infarction aftercare and prescribing the medication that was initiated in the hospital; however, they described deviating from guidelines because of drugs' side effects or patients' intolerances. Some questioned the benefits of medical secondary prevention for the oldest of patients. General practitioners perceived good adherence among their patients who had had an MI while they regarded their methods for assessing medical non-adherence as limited. They perceived diverse reasons for non-adherence, particularly side effects, patients' freedom from symptoms and patients' indifference to health. They attributed mainly negative characteristics, like lack of knowledge and understanding, to non-adherent patients. These characteristics contribute to the difficulty of convincing these patients to take medications as prescribed. General practitioners improved adherence by preventing side effects, explaining the medication's necessity, facilitating intake and involving patients in decision-making. However, about half of the general practitioners reported threatening their patients with negative consequences of non-adherence. CONCLUSIONS: General practitioners should be aware that discharge medication can be insufficient and thus, should always check hospital recommendations for accordance with guideline recommendations. Improving physicians' communication skills and informing and motivating patients in an adequate manner, for example in simple language, should be an important goal in the hospital and the general practitioner setting. General practitioners should assess patients' motivations through motivational interviewing, which no general practitioner mentioned during the interviews, and talk with them about adherence and long-term treatment goals regularly.

Health care utilisation and medication one year after myocardial infarction in Germany - a claims data analysis.

BACKGROUND: After myocardial infarction, guidelines recommend pharmaceutical treatment with a combination of five different types of drugs for prevention in patients. However, studies from different countries have shown that this goal is not achieved in many patients. The aim of this study was to assess both healthcare and prescribed pharmaceutical treatment in the fourth quarter after index myocardial infarction. METHODS: We conducted a claims data analysis with the data of patients who had had a myocardial infarction in the years 2013 or 2014, using information from the largest German health insurance fund ('AOK'). We analysed contact with physicians, hospital care and actual prescriptions for medication recommended in international guidelines, referring to beta-blockers, ACE inhibitors or angiotensin II receptor blockers, P2Y12-antiplatelet agents, acetylsalicylic acid and statins, one year after myocardial infarction. Analysis was stratified by age and sex, compared between patient groups and over time. RESULTS: We identified 2352 patients who had survived myocardial infarction. Some 96.9% of these participants had at least one contact with their general practitioner (GP) one year after myocardial infarction, 22.8% contacted a cardiologist and 19.7% were hospitalised. Prescription rates range from 37.8% for acetylsalicylic acid to 70.4% for ACE inhibitors. However, only 24.1% received statins, beta-blockers, ACE inhibitors and an antiplatelet drug simultaneously. Prescription of recommended drugs after myocardial infarction decreased steadily over time. DISCUSSION: Long-term medical prevention after myocardial infarction is improvable. GPs should take care of the pharmaceutical prevention after myocardial infarction as they are the physicians seen most intensively in this period.