Heißgasfiltration im Synthesegas aus Biomasse

During thermochemical conversion of biological material in a fluidized bed reactor the nutrients are remaining as dust in the product gas. Hot gas filtration represents a possibility to recover these minerals. The characteristics of this gas add up new technical tasks. The following article gives an account of long lasting experience of operation and optimization in a pilot plant.     

The crystal structure of LiMgAlD6 from combined neutron and synchrotron X-ray powder diffraction

LiMgAlH₆ is the intermediate phase when LiMg(AlH₄)₃ is heated. It contains 9.4 wt.% hydrogen, of which 4.8 wt.% is released during the decomposition step to MgH₂ and LiH. Deuterated LiMgAlD₆ was prepared by heat-treating LiMg(AlD₄)₃ at 130 °C. Powder neutron and synchrotron X-ray diffraction patterns were measured and the structure was refined using the Rietveld technique on both patterns simultaneously. LiMgAlD₆ crystallizes in the trigonal space group P321 with a = 7.9856(4) Å and c = 4.3789(3) Å. The structure consists of isolated AlD₆ octahedra connected through octahedrally coordinated Mg- and Li-atoms.     

Simplified gravimetric determination of total fat in food composites after chloroform-methanol extraction

A modification of Association of Official Analytical Chemists (AOAC) method 983.23 for the quantitative determination of total lipid in food composites was evaluated for the measurement of total fat. The procedure is based on the Bligh and Dyer chloroform/methanol total lipid extraction. Relative to AOAC 983.23, the proposed method is less labor-intensive and is applicable to batch analysis of a larger number of samples, thus reducing the cost of analysis and increasing sample throughput. Total lipid values from the proposed method are comparable to those from AOAC 983.23 and slightly higher than total fat determined by acid hydrolysis (AOAC 954.02, 945.44, or 922.06). Recoveries of standard additions of different food-grade oils from a mixed food composite were essentially quantitative, ranging from 96 to 101%. Total lipid measured in Total Diet Standard Reference Material 1548 (SRM 1548, National Institute of Standards and Technology) was 101% of the certified mean total fat content and within the certified range. The method is to be suitable for analysis of food composites with between 0.15 and 1.5 g total fat (3 to 30% by weight). More than 600 samples of a variety of total diet composites were collected and assayed as diet quality control samples for two National Heart, Lung and Blood Institute-sponsored multicenter clinical feeding trials: DELTA (Dietary Effects on Lipoproteins and Thrombogenic Activity) and DASH (Dietary Approaches to Stop Hypertension). The mean coefficient of variation was 1.2% for duplicate assays of these samples over the course of two years and multiple analysts. In addition, total lipid values for more than 200 samples of a diet composite quality control material, used in this laboratory over a two-year period, had a 3.99% coefficient of variation. Although the accuracy of all gravimetric total fat methods with respect to the U.S. Food and Drug Administration’s Nutritional Labeling and Education Act (NLEA) definition of total fat as the sum of triglycerides remains to be determined, the reported modification of AOAC 983.23 yields a total fat content of acceptable accuracy relative to other gravimetric methods, and with proper quality control the method has excellent precision.     

Early specification and autonomous development of cortical fields in the mouse hippocampus

Studies of the specification of distinct areas in the developing cerebral cortex have until now focused mainly on neocortex. We demonstrate that the hippocampus, an archicortical structure, offers an elegant, alternative system in which to explore cortical area specification. Individual hippocampal areas, called CA fields, display striking molecular differences in maturity. We use these distinct patterns of gene expression as markers of CA field identity, and show that the two major hippocampal fields, CA1 and CA3, are specified early in hippocampal development, during the period of neurogenesis. Two field-specific markers display consistent patterns of expression from the embryo to the adult. Presumptive CA1 and CA3 fields (Pca1, Pca3) can therefore be identified between embryonic days 14.5 and 15.5 in the mouse, a week before the fields are morphologically distinct. No other individual cortical areas have been detected by gene expression as early in development. Indeed, other features that distinguish between the CA fields appear after birth, indicating that mature CA field identity is acquired over at least 3 weeks. To determine if Pca1 and Pca3 are already specified to acquire mature CA field identities, the embryonic fields were isolated from further potential specification cues by maintaining them in slice culture. CA field development proceeds in slices of the entire embryonic hippocampus. More strikingly, slices restricted to Pca1 or Pca3 alone also develop appropriate mature features of CA1 or CA3. Pca1 and Pca3 are therefore able to develop complex characteristics of mature CA field identity autonomously, that is, without contact or innervation from other fields or other parts of the brain. Because Pca1 and Pca3 can be identified before major afferents grow into the hippocampus, innervation may also be unnecessary for the initial division of the hippocampus into separate fields. Providing a clue to the source of the true specifying signals, the earliest field markers appear first at the poles of the hippocampus, then progress inwards. General hippocampal development does not follow this pronounced pattern. We suggest that the sources of signals that specify hippocampal field identity lie close to the hippocampal poles, and that the signals operate first on cells at the poles, then move inwards.     

Bias and error rates for premorbid IQ estimators: Comment on Veiel and Koopman (2001).

H. O. F. Veiel and R. F. Koopman (2001) advance statistical and legal theses. They correctly point out that the usual regression formula for estimating a pre-event IQ underestimates high IQs and overestimates low IQs (due to regression to the mean). They call this a conditional bias and show it can be sizeable. The author takes issue with their claim that a new estimator they propose should be used in place of the usual formulas, because it negates this statistical bias. Their argument against the usual estimator conflates statistical bias and legal bias. Their discussion in favor of their new estimator mentions, but does not derive a general formula for, a gross loss of precision entailed by use of the new estimator. The author quantifies this loss of precision and, using Veiel and Koopman's numerical example, shows that their estimator quadruples error. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The cooccurrence of DSM-III-R personality disorders

The distinction between personality disorder diagnoses is often unclear because of the frequent cooccurrence of one or more of the diagnoses. To date, studies using sample sizes large enough to evaluate the rates of cooccurrence in the less prevalent personality disorders have not been conducted. The Structured Interview for Diagnosis of Personality-Revised, a semistructured instrument designed to yield reliable personality disorder diagnoses, was used to evaluate 1116 subjects for the presence of DSM-III-R personality disorder diagnoses. Cooccurrence rates and odds ratios were calculated for each pair of diagnoses. There was a high degree of cooccurrence between the cluster A personality disorders, between the cluster C personality disorders, and between narcissistic, borderline, and histrionic disorders. In addition, there was also a high frequency of avoidant personality disorders within the cluster A personality disorder diagnoses. Possible explanations for the high degree of cooccurrence and the potential implications for the DSM-IV personality disorder diagnoses are discussed.     

First report of the isolation of an adult worm of the genus Brachylaima (Digenea: Brachylaimidae), from the gastrointestinal tract of a human

A 78-year-old woman presented with an 18-month history of intermittent diarrhoea. Examination of her stools revealed brachylaimid eggs, which were present in three separate specimens over a week. After treatment with praziquantel a degenerate adult Brachylaima species was recovered from her faeces. She lived in a rural area of South Australia and ate vegetables grown in her own garden which had been infested with helicid snails. In south Australia these introduced European helicid snails are commonly infected with brachylaimid intermediate larval stages and are considered to be the source of the human infection.