Longitudinal Cavity Mode Referenced Spline Tuning for Widely Tunable MG-Y Branch Semiconductor Laser

This paper presents a novel method for wavelength-continuous tuning of a MG-Y-Branch Laser that possesses an intrinsic self-calibration capability. The method utilizes the measured characteristic output power pattern caused by the internal longitudinal cavity modes of the laser device to calibrate a set of cubical spline curves. The spline curves are then used to generate the tuning currents for the two reflector sections and the phase section of the laser from an intermediate tuning control parameter. A calibration function maps the desired laser wavelength to the intermediate tuning parameter, thus enabling continuous tuning with high accuracy

Nachholimpfungen und Impfungen von Ungeimpften

Zusammenfassung: Die von der Ständigen Impfkommission (STIKO) empfohlenen Standardimpfungen für Kinder und Jugendliche werden von den Eltern nicht immer zum empfohlenen Zeitpunkt akzeptiert. Auch werden häufig empfohlene Auffrischimpfungen nicht verabreicht. Wenn dann zu einem späteren Zeitpunkt Nachholimpfungen gewünscht werden, wirft dies oft Fragen zur erforderlichen Anzahl an Impfdosen sowie zur Reihenfolge und zum Abstand verschiedener Impfungen auf. Bei der individuellen Planung von Nachholimpfungen sind dann bereits dokumentierte Impfungen ("jede Dosis zählt"), das Alter des Patienten und das Geschlecht zu berücksichtigen. Ziel ist es, binnen kurzer Zeit mit möglichst wenigen Injektionen den Impfstatus zu aktualisieren. Hierfür wird eine pragmatische Anleitung gebote

Akute Otitis media: Einfluss der Pneumokokkenimpfung auf die Prävalenz

Zusammenfassung: Die Pneumokokkenimpfung mit Konjugatimpfstoff schützt vor invasiven und auch lokalen Infektionen, z. B. akuter Otitis media (AOM). In der Zulassungsstudie des 7-valenten Konjugatimpfstoffs (Prevenar®) wurde eine Schutzrate von 67% gegen AOM durch im Impfstoff enthaltene Pneumokokkenserotypen ermittelt. Gegenüber jeglicher AOM betrug sie 9%. Der Impfstoff ist neuerdings in der EU auch für die Indikation AOM zugelassen. Seit der Einführung des Pneumokokkenimpfprogramms in den USA im Jahr 2000 bei Kindern bis zum Alter von 2 Jahren liegen nunmehr auch Daten zur klinischen Effizienz vor. So war in einer repräsentativen Erhebung in den USA in den ersten Jahren nach Beginn des Programms ein Rückgang der ambulanten Behandlungen wegen AOM bei unter 2Jahre alten Kindern um 20% zu verzeichnen. Manche Untersuchungen deuten darauf hin, dass dieser Rückgang mit einer relativen Zunahme von AOM durch nicht im Impfstoff enthaltene Serotypen einhergeht ("replacement"). Sorgfältige epidemiologische Untersuchungen begleitend zu Impfprogrammen sind erforderlich, um solche Entwicklungen erkennen zu könne

An update on the prevention of influenza in children and adolescents

Influenza virus types A and B cause yearly outbreaks of respiratory tract infections in all age groups including children and adolescents. Complications, such as high fever, febrile convulsions, secondary bacterial infections and myositis frequently lead to hospitalisation. Safe and effective split, subunit and virosome vaccines are available from 6 months of age onwards. Most European countries do have guidelines for the use of influenza vaccines and current strategies primarily aim at decreasing the burden of influenza disease in certain, heterogeneously defined high risk groups. Conclusion:unfortunately, compliance of many physicians and patients with immunisation recommendations is rather poor and several barriers to immunisation have been identified. These deserve our specific attention in the future. Recently, neuraminidase inhibitors with curative and preventive efficacy against influenza virus types A and B have become available. They serve as second line weapons for influenza prophylaxis under specific circumstance

Interrogation of Optical Fiber Sensors for Civil Engineering Applications using Widely Tunable Laser

Předložená disertační práce zkoumá možnosti použití nového typu polovodičového MGY- Laseru elektricky laditelného v širokém spektrálním rozsahu a zabývá se možnostmi jeho nasazení v optovláknové senzorové síti založené na metodě FBG (Fiber Bragg Grating). Výzkum byl započat komplexními dlouhodobými testy reálného měřícího scénáře z oblasti stavebnictví, sestaveného pro účely ověření limitujících aspektů současných technik. Inženýrské aplikace nabízejí velké množství vzájemně se vylučujících požadavků pro návrh strukturálních senzorových systémů. Tyto požadavky jsou sdíleny mnoha dalšími technologickými oblastmi, což přispívá k vysokému stupni univerzálnosti použití dosažených výsledků. Na základě posouzení stavu současné techniky a aplikačních požadavků byly v práci nejprve identifikovány aspekty, které mají být výzkumem zlepšeny. V dalším kroku byl detailně charakterizován MG-Y laser Syntune/Finisar S7500. Na základě dat získaných měřením byla zkoumána nová metoda spojitého řízená vlnové délky záření laseru. Provedené experimenty vedly nejen k návrhu nového způsobu spojité regulace vlnové délky ale také k vytvoření prostředků pro vlastní kalibraci systému na základě jeho vnitřních vlastností (podélných módů rezonátoru).This dissertation investigates the use of a MG-Y-Laser, a novel type of semiconductor laser that is electrically tunable over a wide spectral range, for the interrogation of Fiber Bragg Grating (FBG) based fiber-optical sensing networks. The research started with a complex long-term test of a real world measurement scenario from the field of civil engineering to elucidate limiting aspects of state of the art techniques. Civil engineering applications pose a multitude of mutually exclusive challenges toward structural sensing systems. These challenges are shared by many other fields of technology, making the results to a large degree universally applicable. Following an assessment of the state of art and the application requirements, the aspects to be improved by the research were identified. A Syntune/Finisar S7500 MG-Y-Laser device was then thoroughly characterized. Based on the gathered measurement data, novel tuning methods aimed at wavelength continuous control were investigated. This led to the invention of a tuning method that not only allows wavelength continuous control but also provides a means of self calibration based on intrinsic properties (longitudinal cavity modes) of the device.

No temporal association between influenza outbreaks and invasive pneumococcal infections

Objective: To assess whether the influenza peak in populations precedes the annual peak for invasive pneumococcal infections (IPI) in winter.Design: Ecological study. Active surveillance data on influenza A and IPI in children up to 16 years of age collected from 1997 to 2003 were analysed.Setting: Paediatric hospitals in Germany.Patients: Children under 16 years of age.Results: In all years under study, the influenza A season did not appear to affect the IPI season (p = 0.49). Specifically, the influenza peak never preceded the IPI peak.Conclusion: On a population level there was no indication that the annual influenza epidemic triggered the winter increase in the IPI rate or the peak of the IPI distribution in children

Protecting newborns from pertussis – the challenge of complete cocooning

BACKGROUND: An increase of pertussis cases, especially in young infants and adolescents, has been noted in various countries. Whooping cough is most serious in neonates and young infants in whom it may cause serious complications such as cyanosis, apnoea, pneumonia, encephalopathy and death. To protect newborns and infants too young to be fully immunized, immunization of close contact persons has been proposed (“cocoon strategy”) and implemented in several countries, including Switzerland in 2011. The goal of this study was to assess knowledge about pertussis among parents of newborns and acceptance, practicability and implementation of the recently recommended pertussis cocoon strategy in Switzerland. METHODS: We performed a cross sectional survey among all parents of newborns born between May and September 2012 and 2013 in Basel city and country. Regional statistical offices provided family addresses after approval by the ethical and data protection committees. A standardized questionnaire with detailed instructions was sent to all eligible families. For statistical analyses, independent proportions were compared by Pearson’s chi-squared test. RESULTS: Of 3546 eligible parents, 884 (25%) participated. All three questions exploring pertussis knowledge were answered correctly by 37% of parents; 25% gave two correct answers, 22% gave one correct answer and in the remaining 16% no answer was correct. Pertussis immunization as part of cocooning was recommended to 20% and 37% of mothers and 14% and 32% of fathers in the 2012 and 2013 study cohorts, respectively. Principal advisors for cocooning were pediatricians (66%) followed by gynecologists/obstetricians (12%) and general practitioners (5%). When recommended, 64% of mothers and 59% of fathers accepted pertussis immunization. The majority of vaccinations were administered in the perinatal period and within 2 months of the child’s birth. However, cocooning remained incomplete in 93% of families and in most families <50% of close contacts received pertussis vaccination. CONCLUSIONS: Implementation of cocooning for protecting newborns from pertussis is challenging and usually remains incomplete. Pertussis immunization rates among close contacts of newborns need to be improved. Ideally, all healthcare providers involved in family planning, pregnancy and child birth should recommend cocooning. Pertussis immunization of pregnant women is an additional measure for optimal protection of newborns and should be promoted

Immunization rates and timely administration in pre-school and school-aged children

Whereas immunization coverage has been repeatedly assessed in the Swiss population, little is known about the timely administration of universally recommended immunizations in Switzerland and elsewhere. The goal of this study was to determine compliance with official standard immunization recommendations in pre-school and school-aged children in Basel, Switzerland, focusing on coverage rates and timely administration. Of a cohort of children entering kindergarten and third-grade primary school in Basel in 2001, 310 and 310, respectively, were identified in proportion to the overall age-appropriate populations in the four city districts. Foreign-born children were excluded. The data were extracted from immunization records provided voluntarily by parents. Coverage for three doses of diphtheria, tetanus, and poliomyelitis vaccines was >95% and <90% for pertussis and Hib. The rates of age-appropriate booster doses were significantly lower, especially for pertussis and Hib (<60%). Cumulative coverage for measles, mumps, and rubella (MMR) was <90% for the first dose and 33% for the second dose by 10 years of age. All immunizations were administered with significant delays. Coverage for the first three doses of DTP combination vaccines did not reach 90% before 1 year of age and, for the first dose of MMR, a plateau just below 80% was not reached before 3 years of age. Delayed administration of immunizations in childhood, as well as complete lack of booster doses in a significant fraction of children, with important implications for public health have been discovered in this study. This may lead to fatal disease in individuals, epidemics in the community, and threatens national and international targets of disease elimination, such as measles and congenital rubella syndrom