A 500-kiloton airburst over Chelyabinsk and an enhanced hazard from small impactors.

Most large (over a kilometre in diameter) near-Earth asteroids are now known, but recognition that airbursts (or fireballs resulting from nuclear-weapon-sized detonations of meteoroids in the atmosphere) have the potential to do greater damage than previously thought has shifted an increasing portion of the residual impact risk (the risk of impact from an unknown object) to smaller objects. Above the threshold size of impactor at which the atmosphere absorbs sufficient energy to prevent a ground impact, most of the damage is thought to be caused by the airburst shock wave, but owing to lack of observations this is uncertain. Here we report an analysis of the damage from the airburst of an asteroid about 19 metres (17 to 20 metres) in diameter southeast of Chelyabinsk, Russia, on 15 February 2013, estimated to have an energy equivalent of approximately 500 (±100) kilotons of trinitrotoluene (TNT, where 1 kiloton of TNT = 4.185×10(12) joules). We show that a widely referenced technique of estimating airburst damage does not reproduce the observations, and that the mathematical relations based on the effects of nuclear weapons--almost always used with this technique--overestimate blast damage. This suggests that earlier damage estimates near the threshold impactor size are too high. We performed a global survey of airbursts of a kiloton or more (including Chelyabinsk), and find that the number of impactors with diameters of tens of metres may be an order of magnitude higher than estimates based on other techniques. This suggests a non-equilibrium (if the population were in a long-term collisional steady state the size-frequency distribution would either follow a single power law or there must be a size-dependent bias in other surveys) in the near-Earth asteroid population for objects 10 to 50 metres in diameter, and shifts more of the residual impact risk to these sizes.

Quality of care of VLBW neonates: relationship between unit volume and outcome is different between metropolitan and rural regions.

BACKGROUND: Recent studies from predominantly rural areas in Germany show that neonatal outcome of very low birth weight (VLBW) neonates is (on average) inferior with lower NICU (neonatal intensive care unit) volume. However, there are no data available which show that study results of one specific region can be transferred to other areas with possibly different medical infrastructure and needs. AIM: It was investigated whether a systematic difference of treatment quality between smaller (1000-2000 births/year; < or =20 neonatal beds) vs. larger neonatal centres in Berlin (>3000 births/year; >20 neonatal beds) exists. Furthermore, the results are compared to data from a rural region in order to discuss transferability between regions. METHODS: Retrospectively, completely, and for the first time, the data of all centres which treat VLBW neonates (< or =1500 g birth weight) in the city-state of Berlin, Germany, from the years 2003/2004 were reviewed. RESULTS: Our study showed no difference in the treatment quality of smaller vs. larger neonatal units in Berlin. This result differs from those of a study in Baden-Württemberg, a predominantly rural state, with different medical infrastructure than Berlin. CONCLUSION: The present study suggests that regional investigations on the infrastructure vs. treatment outcome are not transferable between areas. Patient volume/unit appears inadequate for predicting the future treatment quality of neonatal departments. Direct quality indicators are stable for the assessed departments and should be preferably used to organize medical infrastructure.

[Emergency laparoscopy in patients with multiple trauma (author's transl)]. / Die Notfall-Laparoskopie beim polytraumatisierten Patienten.

In 83 patients with multiple trauma emergency laparoscopy spared the patient a formal laparotomy in 46%. 95% of the laparoscopies gave unequivocal clinical information. Emergency laparoscopy is less invasive and of special value in patients with multiple trauma and poor general condition.

[Indications of laparoscopy in abdominal diseases (author's transl)]. / Die Indikation zur Laparoskopie bei abdominalen Erkrankungen.

On the basis of 900 laparoscopies it is attempted to define the indications of laparoscopy in abdominal diseases. 6 groups of indications could be differentiated. The diagnostic accuracy of laparoscopy allows in many cases to replace exploratory laparotomy by laparoscopy.

[Partial monosomy 21 or fetal alcohol embryopathy in a retarded boy?]. / Partielle Monosomie 21 oder Alkoholembryofetopathie bei einem retardierten Knaben?

A male newborn showed dysmorphisms combined with a complex cerebral malformation and a growth retardation. Alcohol damage in utero was suspected to be the cause. A deletion 21q (mosaic) was found in the karyotype.

Evaluation of a rapid whole blood test to detect Helicobacter pylori infection in children.

BACKGROUND: Rapid, patient near tests for detecting antibodies against Helicobacter pylori are offered for clinical use. We evaluated the BM-Test (Boehringer Mannheim, Germany; identical to the Helisal Rapid Blood Test) in children with recurrent abdominal pain. METHODS: The BM-Test and 13C-urea breath test (UBT) were performed in 195 children (4-18 years). Symptoms were assessed using a 4-week diary. Upper endoscopy was performed in all UBT-positive children and in UBT-negative children with symptoms suggestive of organic disease. H. pylori status was considered positive if at least two of three methods (UBT, histology or rapid urease test) or culture were positive. RESULTS: After exclusion of children with previous H. pylori therapy (n = 8) and undetermined H. pylori status (n = 1), 61/186 (33%) children were H. pylori positive. The BM-Test in relation to H. pylori status revealed a sensitivity of 54%, specificity of 90%, a likelihood ratio of 5.2 for a positive, and of 0.4 for a negative test result. Accuracy of the test was independent of ethnicity, gender, age, family history for ulcer disease, frequency or severity of abdominal symptoms, epigastric tenderness, type of blood sampling (capillary versus venous) and DOB values of the UBT. In eight previously treated children, the test gave one false-positive and three false-negative results. CONCLUSIONS: Almost half of H. pylori-infected children and 10% of non-infected children were misclassified by the BM-Test. False-negative results are not related to young age or certain ethnic groups. The poor performance makes the test unsuitable for epidemiological and clinical use in children.