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L Köhler

Publications and source records attributed to L Köhler.

At least 19 recordsLinked to original sources

Initial oxidation of the Rh(110) surface: ordered adsorption and surface oxide structures.

The initial oxidation of the Rh(110) surface was studied by scanning tunneling microscopy, core level spectroscopy, and density functional theory. The experiments were carried out exposing the Rh(110) surface to molecular or atomic oxygen at temperatures in the 500-700 K range. In molecular oxygen ambient, the oxidation terminates at oxygen coverage close to a monolayer with the formation of alternating islands of the (10x2) one-dimensional surface oxide and (2x1)p2mg adsorption phases. The use of atomic oxygen facilitates further oxidation until a structure with a c(2x4) periodicity develops. The experimental and theoretical results reveal that the c(2x4) structure is a "surface oxide" very similar to the hexagonal O-Rh-O trilayer structures formed on the Rh(111) and Rh(100) substrates. Some of the experimentally found adsorption phases appear unstable in the phase diagram predicted by thermodynamics, which might reflect kinetic hindrance. The structural details, core level spectra, and stability of the surface oxides formed on the three basal planes are compared with those of the bulk RhO2 and Rh2O3.

Journal Article↗

Health, economy and social capital in Nordic children and their families: a comparison between 1984 and 1996.

OBJECTIVE: The aim of the study was to analyse the development in the health of children that occurred in the five Nordic countries (Denmark, Finland, Iceland, Norway and Sweden) between 1984 and 1996 and relate it to the changes in economic growth and social capital in these countries during the same period. METHODS: Two cross-sectional studies covered a representative sample of children, aged 2-17 years in each country, a total of 10,291 in 1984 and 10,317 in 1996. The data were collected by mailed questionnaires. Statistical associations between a health indicator (the absence of psychosomatic complaints), economic indicators (social class, housing and disposable income) and social capital indicators (parents' and children's organized group activities, parents playing with their children and the absence of bullying) within samples and between corresponding values in different samples across subgroups (defined by country and area of residence) were evaluated using multiple linear regression. RESULTS: In both surveys, there was a statistically highly significant association between the health indicator and the social capital indicators, whereas the economy indicators were not related to either of the other two types of measure. Change in health was associated positively with change in social capital and negatively with change in economy. CONCLUSION: The study provides strong support for the concept of social capital as an important determinant of children's health.

Adolescent↗

Children's use of general practitioner services in the five Nordic countries.

OBJECTIVE: To compare socioeconomic, sociodemographic, and living area differences in children's use of GP services in five Nordic countries from the 1980s to the 1990s and to analyse trends during the period. DESIGN: Cross sectional population surveys using random samples comprising 3000 children aged 2-17 years were conducted in 1984 and 1996 in five Nordic countries. Time trends in use of GP services were studied in each country by age, sex, parents' highest level of education, and living area. SETTING: Five Nordic countries, Denmark, Finland, Iceland, Norway, and Sweden in 1984 and 1996. PARTICIPANTS: A total sample of 15 000 children aged 2-17 years. Altogether 3000 children were selected at random from the national population registers of the national bureaus of statistics in each country. MAIN OUTCOME: Health services utilisation on the basis of responses to a questionnaire item asking whether the parents had consulted a GP with regard to their children's health during the previous three months. MAIN RESULTS: The prevalence of children's utilisation of GP services varied from 14% in 1984 in Sweden to 28% in 1996 in Iceland. A clear time trend towards increasing utilisation of GP services (p<0.05) was found in all countries except in Denmark. Odds ratios for time trends (1984 = 1.00) varied from 1.22 (1.02 to 1.46) in Sweden to 1.92 (1.62 to 2.30) in Norway. After adjusting for independent variables, a statistically borderline significant declining utilisation trend (OR = 0.85 (0.70 to 1.03)) was found for Denmark. CONCLUSION: Children's use of GP services has increased significantly in four of the five Nordic countries.

Adolescent↗

Parental reported bullying among Nordic children: a population-based study.

BACKGROUND: Bullying has been shown to be a serious problem amongst school children, but few studies have been population-based and included pre-school children. METHODS: The study is part of a cross-sectional comparative study in 1984 and 1996, focusing on children's and their families' health and welfare in the Nordic countries. At each point of time parents of 3000 randomly selected children aged 2-17 years in each of five Nordic countries received a postal questionnaire. Altogether approximately 20,000 questionnaires were completed. The prevalence of bullying, risk factors for bullying and possible effect factors were analysed. RESULTS: Parents reported bullying of their child in 15.1% of the cases. Bullying varied from 7.2% in Sweden to about 20% in Denmark and Finland. There was a small increase in bullying from 13.7% in 1984 to 16.4% in 1996. Bullying was most frequent in boys (OR: 1.4) and in children 2-6 and 7-12 years old (OR: 2.0 and 2.2 compared with older children). Children of single parents and of parents with low education had increased risks (OR: 1.4 and 1.4). Children with chronic conditions had higher risks for being bullied (OR: 2.3). In 1996 children with psychiatric/nervous problems and hyperactivity had high risks for being bullied (OR: 8.8 and 10.5) and for bullying others (3.9 and 3.5). Being bullied was associated with poor thriving and psychosomatic and psychological problems. No countries had national interventions before 1984, but Sweden had early focused on the problem and implemented a strong national policy before 1996. After 1996 national anti-bullying policies were strengthened in the Nordic countries, most in Sweden and Norway. CONCLUSION: Bullying is common among Nordic children, including pre-school children. Bullying is a threat to children's health, and augments problems in children with chronic conditions. The low prevalence of bullying in Sweden may be a result from sustained, strong anti-bullying policies. There is still a need for continuing interventions.

Adolescent↗

High-coverage oxygen structures on Rh111: adsorbate repulsion and site preference is not enough.

A new O induced structure on Rh(111) displaying a (2 sqaureroot[3] x 2sqaureroot[3])R30 degrees periodicity with an oxygen coverage of 2/3 has been studied by high resolution core level spectroscopy, scanning tunneling microscopy, and density functional theory. Although O favors fcc hollow sites in all other known phases, it occupies both fcc and hcp sites in this structure, which cannot be explained by pairwise adsorbate repulsion only. Both the (2sqaureroot[3] x 2sqaureroot[3])R30 degrees and (2 x 2)-3O structures also exemplify that density-of-states contrast can lead to oxygen adatoms appearing as protrusions in scanning tunneling microscopy images.

Journal Article↗

Self-limited growth of a thin oxide layer on Rh(111).

The oxidation of the Rh(111) surface at oxygen pressures from 10(-10) mbar to 0.5 bar and temperatures between 300 and 900 K has been studied on the atomic scale using a multimethod approach of experimental and theoretical techniques. Oxidation starts at the steps, resulting in a trilayer O-Rh-O surface oxide which, although not thermodynamically stable, prevents further oxidation at intermediate pressures. A thick corundum like Rh2O3 bulk oxide is formed only at significantly higher pressures and temperatures.

Journal Article↗

Port function after laparoscopic adjustable gastric banding for morbid obesity.

BACKGROUND: Laparoscopic adjustable gastric banding (LGB) has gained wide popularity, but information on port function is limited. METHODS: In a prospective nonrandomized study, we analyzed port function and related symptoms in 50 consecutive patients with severe obesity. All patients underwent LGP in a five trocar technique. In 11 patients, the port was placed subcutaneously in the subxiphoid region. In 39 patients, the port was implanted in the left upper abdomen. Mean duration of follow-up was 2.8 years. RESULTS: Patients (12 males and 38 females) had an initial body mass index (BMI) of 47.1 kg/m2. Puncturing the subxiphoidal port was without problems in all 11 patients. However, seven women reported pain and inconvenience when wearing a brassiere. Two underwent port reimplantation in the left upper abdomen (one due to infection; one due to pain). Among the 39 patients with abdominal port implantation, nine patients required port correction (two of them twice). The causes were port dislocation (four cases), difficult puncturing (three), tube leakage (three), and infection (one). CONCLUSION: The high number of complications suggests that the port is the Achilles' heel of LGB. Ports at the subxiphoid site were easier to puncture, but frequently caused pain in female patients.

Adult↗

[Organization of pain therapy in surgery--comparison of acute pain service and alternative concepts].

An acute pain service done by surgeons is one possibility for organizing pain therapy in surgical wards. To do this successfully, some preconditions must be kept in mind, such as 24-h presence, an integrated system of documentation, and teamwork between medical and nursing staff. Comparison of differently structured pain therapy in three different hospitals (with and without acute pain service) showed high levels of patient satisfaction with the pain therapies in all three hospitals. One of the preconditions for effective pain therapy in surgery is to formulate a concept which takes into account the specific situation of each hospital.

Acute Disease↗

ESSOP--25 years: personal reflections from one who started the European Society for Social Paediatrics.

ESSOP--the European Society for Social Paediatrics--was initiated in Lund, Sweden in 1977, and at the annual congress in Spetses, Greece, its 25th anniversary was celebrated. At the congress, Professor Lennart Köhler, who started the organization and for 10 years was its first Secretary General, presented his recollections from the life of ESSOP, its people, activities, strategies and ideologies, and the main lines of development over the years. This paper presents an edited version of his speech for the benefit of the readers of Child: Care, Health and Development.

Child↗

Indicators of children's development: considerations when constructing a set of national Child Health Indicators for the European Union.

BACKGROUND: In a recent project, commissioned by the European Union, a set of Child Health Indicators were identified and recommended for use in all Member States. In that work, by a group of European experts, children's development was one of the key areas that were reviewed to clarify its role in this set of indicators. This paper deals with neurological (in a broad sense), social and moral aspects of development; other aspects, such as nutrition and physical growth, mental health, quality of life were dealt with in other areas. METHODS: A number of methods are used to monitor children's neurodevelopment, to identify early deviations that could be treated or alleviated. Few tests fulfil basic criteria of screening and quality of evidence. For Child Health Programmes, developmental surveillance is instead recommended. As a proxy to social development, as part of children's process of adaptation into society, education indicators are recommended, such as suggested by OECD and UNICEF. Moral development is discarded as an indicator, because norms and values vary too much between countries. CONCLUSION: For now the Child Health Indicators of Life and Development Project found no ground to recommend any particular method or combination of methods for a general monitoring of children's neurological, intellectual, language and moral development, and for including the results as national indicators of children's health and well-being in EU. For social development, indicators in the educational area seem most promising, as they have been proposed and used by OECD and UNESCO. In an ambitious monitoring programme, these indicators could be included as determinants of children's health and development.

Adaptation, Psychological↗

[Percutaneous endoscopic gastrostomy (PEG). Course, nutrition and care in 233 consecutive patients].

AIM: To evaluate the course, nutrition and care of PEG tubes on the basis of data collected from 233 consecutive patients. PATIENTS AND METHOD: Between 1.1.1990 and 31.3.1996, a total of 243 PEG tubes were implanted in 233 patients--56.5% male and 43.5% female--with an average age of 66.2 years. 57.3% had neurological, and 19.4% neurosurgical, diseases, 11.2% suffered polytraumatization or severe burns, and 8.2% had a malignancy. Patients stayed with the implanted tube on average 153 days, with neurological patients leading the field at 189 days. RESULTS: The overall complication rate was 14.5%, with the most common complication being local infection, which occurred in 5.4% of the cases. Severe complications were seen in 1.2%. One patient developed a necrotizing fasciltis, and in two others, migration of the tube was observed. 52.2% of the patients died with the tube still in place. In 33.6%, the PEG tube was removed after a mean of 82.7 days, when adequate oral nutrition again became possible. CONCLUSION: In this study, PEG proved an effective method for enteral nutrition over the middle-to-long-term in multimorbid and intensive care patients, as well as in those with malignant disease.

Adolescent↗

A rare complication of laparoscopic adjustable gastric banding.

The most common complications of laparoscopic gastric banding (LGB) are band dislocation, port problems, and leakage in the band system. We present a case of an aneurysmal dilatation of the balloon portion of the band by filling as a rare complication of LGB. A 53-year-old male patient with morbid obesity (body mass index 40 kg/m2) was treated with LGB (adjustable Bioenterics gastric band). Six months after the operation there was no evidence of weight reduction. X-ray examination showed the band to be in the correct position. The port punction revealed no spontaneous fluid loss. The contrast filling of band demonstrated no signs of leakage but there was an abnormal dilatation of one part of the balloon. Only one filling segment of balloon was dilatated and the rest was empty. Two and a half years after the initial operation, we carried out laparoscopic band exchange. Six weeks later, the band was adjusted with 2 ml saline, and the patient reported successful reduction of food volume. He had lost 18 kg 3 months postoperatively. We conclude that band function requires careful intraoperative monitoring. In patients who do not lose weight after gastric restriction surgery, uncommon complications must also be considered.

Body Mass Index↗

[New aspects of bacteriological pathogen diagnosis in rheumatic diseases].

Microbiological diagnosis for rheumatic diseases is increasingly used as part of the diagnostic work-up in rheumatological practice due to growing knowledge about bacteria-induced rheumatic diseases. This review's focus lies on rheumatic diseases, which in contrast to septic-infectious arthritis, are characterized by the inability to culture bacteria from the inflammed joint. These reactive arthritides occur after primary extraarticular bacterial infection. The etiological diagnosis of reactive arthritis is based on the detection of a previous or ongoing bacterial infection. Diagnosis is performed by serology or direct detection of the bacterial organism or parts thereof at the site of entry and recently by molecularbiology-based detection of the bacteria in the inflamed joint. This review reflects the current diagnostic approaches and formulates diagnostic algorithms for specific and well-directed microbiological diagnosis.

Algorithms↗

Standardised nomenclature for glucocorticoid dosages and glucocorticoid treatment regimens: current questions and tentative answers in rheumatology.

In rheumatology and other medical specialties there is a discrepancy between the widespread use and the imprecise designation of glucocorticoid treatment regimens. Verbal descriptions of glucocorticoid treatment regimens used in various phases of diseases vary between countries and institutions. Given this background, a workshop under the auspices of the EULAR Standing Committee on International Clinical Studies including Therapeutic Trials was held to discuss this issue and to seek a consensus on nomenclature for glucocorticoid treatment. This report summarises the panel's discussion and recognises that answers derived from consensus conferences are not definitive. Nevertheless, recommendations on glucocorticoid treatment are presented that (1) reflect current and best knowledge available and (2) take into account current clinical practice. A question-answer rationale presentation style has been chosen to convey the messages, to summarise the meeting in a readable format, and to avoid dogmatism.

Drug Administration Schedule↗

Socioeconomic differences in children's use of physician services in the Nordic countries.

OBJECTIVE: To assess the relation between socioeconomic factors and the use of physician services among children and whether variations of the level of co-payment are correlated with different levels of inequalities in health services use. DESIGN: Description of the socioeconomic differences in the use of health care using data from countrywide postal surveys to parents. SETTING: The five Nordic countries in 1996. SUBJECTS: Samples of 15 000 children aged 2-17 years: 3000 children at random, from the national registry in each country. MAIN OUTCOME MEASURE: Odds ratios of use of GP, specialist, and hospital services between children according to the educational level of both parents and the disposable income of the family, for all countries together and for each country separately. Odds ratios were adjusted for age, sex, urbanisation grade, and health status. RESULTS: There was little difference in the use of GP services according to socioeconomic factors. Parents from lower socioeconomic groups used telephone services of physicians less than parents from the higher groups and children of lower socioeconomic groups were seen less often by specialists. The reverse was true for hospitalisation of the children. The differential use of those three types of services was more marked in Denmark, Finland and Norway than in Iceland and Sweden. When controlled for other socioeconomic factors, the largest differences were observed according to the education of the mother. CONCLUSION: The specialist services and use of telephone services for children in the Nordic countries do not meet the criteria of equal use for equal need whereas the GP services and hospital services do to some extent. The education of the mother is a more important determinant than income for the use of each service.

Adolescent↗

Laparoscopic abdominoperineal resection and anterior resection with curative intent for carcinoma of the rectum.

BACKGROUND: Within a 5-year period, 380 rectal carcinoma patients undergoing laparoscopic abdominoperineal excision or laparoscopic anterior resection were recruited to a multicenter study by 23 institutions in Germany and Austria. This study was initiated by the Laparoscopic Colorectal Surgery Study Group. RESULTS: One hundred forty-nine patients (39.2%) underwent abdominoperineal resection (APR), and 231 patients (60.8%) were treated by anterior resection (AR). The mean operating time was 208 min, and the conversion rate was 6.1%. Intraoperative complications, mostly vascular or bowel injuries, were observed in 22 patients (5.8%). Overall, a total of 257 postoperative complications and problems occurred in 143 patients, resulting in a morbidity rate of 37.6%. In the AR group, the anastomotic leakage rate increased as the distance of the tumor from the anal verge decreased. The perioperative mortality rate was low (6/1.6%). Most of the patients received a high transsection of the inferior mesenteric artery with radical lymph node dissection (342/90.0%); the mean number of recovered lymph nodes was 13.0, with considerable variation among the individual institutions. Intraoperative tumor cell spillage was reported in 12 patients (3.2%). Sufficient follow-up findings are available for 288 (77%) patients. To date, 19 patients have sustained a local recurrence (6.6%), and 30 (10.4%) have developed distant metastases. Within the (admittedly limited) mean follow-up of 24.8 months, the overall survival rate is 86.6%, the disease-free survival (freedom from both local recurrence and distant metastases) rate is 62.4% for APR, with the corresponding rates for AR being 71.7 and 54.8%, respectively, as established by the Kaplan-Meier function. These data show no alarmingly high recurrence rates at this time. CONCLUSION: In principle, laparoscopic anterior resection with curative intent generates considerably more reservations than laparoscopic abdominoperineal resection, which is technically much easier to perform.

Abdomen↗

Importance of conversion for results obtained with laparoscopic colorectal surgery.

PURPOSE: The need for a conversion is a problem inherent in laparoscopic surgery. The present study points up the significance of conversion for the results obtained with laparoscopic colorectal surgery and identifies the risk factors that establish the need for conversion. METHOD: The study took the form of a multicentric, prospective, observational study within the Laparoscopic Colorectal Surgery Study Group. A total of 33 institutions in Germany, Austria, and Switzerland participated. The study period was 3.5 years. Cases were documented with the aid of a standardized questionnaire. RESULTS: Within the framework of the Laparoscopic Colorectal Surgery Study Group, a total of 1,658 patients were recruited to a multicenter study over a period of three and one-half years (from August 1, 1995 to February 1, 1999). The observed conversion rate was 5.2 percent (n = 86). The patients requiring a conversion were significantly heavier (body mass index, 26.5 vs. 24.9) than those undergoing pure laparoscopy. Resections of the rectum were associated with a higher risk for conversion (20.9 vs. 13 percent). Intraoperative complications occurred significantly more frequently in the conversion group (27.9 vs. 3.8 percent). The duration of the operation was significantly increased after conversion in a considerable proportion of the procedures performed. Postoperative morbidity (47.7 vs. 26.1 percent), mortality (3.5 vs. 1.5 percent), recovery time, and postoperative hospital stay were all negatively influenced by conversion, in part significantly. Institutions with experience of more than 100 laparoscopic colorectal procedures proved to have a significantly lower conversion rate than those with experience of fewer than 100 such interventions (4.3 vs. 6.9 percent). CONCLUSION: Although, of itself, conversion is not considered to be a complication of laparoscopic surgery, it is true that the postoperative course after conversion is associated with appreciably poorer results in terms of morbidity, mortality, convalescence, blood transfusion requirement, and postoperative hospital stay. The importance of experience in laparoscopic surgery can be demonstrated on the basis of the conversion rates. Careful patient selection oriented to the experience of the surgeon is required if we are to keep the conversion, morbidity, and mortality rates of laparoscopic colorectal procedures as low as possible.

Age Distribution↗