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.

Cocaine/polydrug use in pregnancy: two-year follow-up

The impact of cocaine on pregnancy and neonatal outcome has been well documented over the past few years, but little information regarding long-term outcome of the passively exposed infants has been available. In the present study, the 2-year growth and developmental outcome for three groups of infants is presented: group 1 infants exposed to cocaine and usually marijuana and/or alcohol (n = 106), group 2 infants exposed to marijuana and/or alcohol but no cocaine (n = 45), and group 3 infants exposed to no drugs during pregnancy. All three groups were similar in racial and demographic characteristics and received prenatal care through a comprehensive drug treatment and follow-up program for addicted pregnant women and their infants. The group 1 infants demonstrated significant decreases in birth weight, length, and head circumference, but by a year of age had caught up in mean length and weight compared with control infants. The group 2 infants exhibited only decreased head circumference at birth. Head size in the two drug-exposed groups remained significantly smaller than in control infants through 2 years of age. On the Bayley Scales of Infant Development, mean developmental scores of the two groups of drug-exposed infants did not vary significantly from the control group, although an increased proportion of group 1 and 2 infants scored greater than two standard deviations below the standardized mean score on both the Mental Developmental Index and the Psychomotor Developmental Index compared with the control infants. Cocaine exposure was found to be the single best predictor of head circumference.(ABSTRACT TRUNCATED AT 250 WORDS)

A radioimmunoassay for the antimalarial drug chloroquine

We describe a 3H-based RIA for the antimalarial drug chloroquine (CLQ), the most commonly used antimalarial drug. In the assay a monoclonal antibody is used that is directed against 4-amino-7-chloroquinoline conjugated to keyhole limpet hemocyanin by the glutaraldehyde method. Besides CLQ, this antibody also recognizes with good affinity the 4-aminoquinoline homologs, hydroxychloroquine and amodiaquine. No extraction step or sample preparation is required, and the method can detect as little as 10 micrograms/L, the lower concentration in plasma of humans who are taking CLQ as a preventive measure. The between-assay CV is less than or equal to 10%, the within-assay CV less than or equal to 3%. Results correlate with those by liquid chromatography (r2 = 0.96). The speed and simplicity of the RIA method make it useful in evaluating the CLQ concentrations in acutely toxic patients.

A radioimmunoassay for the antimalarial drug chloroquine

We describe a 3H-based RIA for the antimalarial drug chloroquine (CLQ), the most commonly used antimalarial drug. In the assay a monoclonal antibody is used that is directed against 4-amino-7-chloroquinoline conjugated to keyhole limpet hemocyanin by the glutaraldehyde method. Besides CLQ, this antibody also recognizes with good affinity the 4-aminoquinoline homologs, hydroxychloroquine and amodiaquine. No extraction step or sample preparation is required, and the method can detect as little as 10 micrograms/L, the lower concentration in plasma of humans who are taking CLQ as a preventive measure. The between-assay CV is less than or equal to 10%, the within-assay CV less than or equal to 3%. Results correlate with those by liquid chromatography (r2 = 0.96). The speed and simplicity of the RIA method make it useful in evaluating the CLQ concentrations in acutely toxic patients.

Monoclonal antibodies to lipophilic and short-sized haptens: application to the 4-amino-quinoline antimalarial drugs

Monoclonal antibodies recognizing the 4-amino-7-chloro-quinoline (ACQ) structure, which represents the backbone of the 4-amino-quinoline antimalarial drugs, were obtained in mice, after injection of ACQ coupled to hemocyanin via the glutaraldehyde method. The resulting antibodies show a definite specificity to this hapten, but react better with compounds substituted on the exocyclic amino group in 4. It is postulated that the quinoline ring is not sufficient for the reaction with the antibodies, and that an enlarged structure, which is given by the bridge used to link hapten and carrier, entails an important increase (1000-fold) in the apparent affinity. The striking similarities between this bridge and the lateral chains of the antimalarial drugs are accountable for this enhanced recognition. This result allows us to indicate that in some instances, the bridge-structure of the immunogen should be positively involved in the epitope. This observation may become useful in the conception of immunogens, aiming to obtain antibodies directed against some lipophilic and small-sized haptens.