Accident investigation reporting deficiencies related to organizational factors in machinery space fires and explosions

Careful accident investigation provides opportunities to review safety arrangements in socio-technical systems. There is consensus that human intervention is involved in the majority of accidents. Ever cautious of the consequences attributed to such a claim vis-à-vis the apportionment of blame, several authors have highlighted the importance of investigating organizational factors in this respect. Specific regulations to limit what were perceived as unsuitable organizational influences in shipping operations were adopted by the International Maritime Organization (IMO). Guidance is provided for the investigation of human and organizational factors involved in maritime accidents. This paper presents a review of 41 accident investigation reports related to machinery space fires and explosions. The objective was to find out if organizational factors are identified during maritime accident investigations. An adapted version of the Human Factor Analysis and Classification System (HFACS) with minor modifications related to machinery space features was used for this review. The results of the review show that organizational factors were not identified by maritime accident investigators to the extent expected had the IMO guidelines been observed. Instead, contributing factors at the lower end of organizational echelons are over-represented.     

Scanning droplet cell investigations on single grains of a FeAlCr light weight ferritic steel

Polycrystalline Fe7.5Al7Cr is a ferritic light weight steel that shows a strong anisotropic dissolution behaviour. This electrochemical phenomenon was investigated by use of a scanning droplet cell (SDC). The crystallographic orientation of the single grains was determined by electron back scatter diffraction (EBSD). The fraction of grains with a near 〈1 1 1〉 orientation (<10°) was 1.88 times higher than that of the near 〈0 0 1〉 orientation prior to annealing and 3.58 times higher after annealing. Voltammograms were performed on single grains with low index planes. The critical current density was 53% higher on 〈0 0 1〉 grains as compared to 〈1 1 1〉 grains. These results are used to discuss the electrochemical behaviour of the polycrystalline FeAlCr.     

Effects of establishment of community psychiatry in Aalborg]

The aim of the present study was to illustrate the effects of community-based psychiatry. The catchment area was divided into three homogeneous districts, East, North and West. Teams were established on 1.9. 1990, 1.10.91 and 1.5.1992, respectively. Social, diagnostic and treatment related data were gathered from two cross-sectional investigations (I: February 1992 and II: February 1993) and from in-patients and out-patients files. In cross-section I a majority of long-term ward patients and hospital-based employment offers was found in the district where the community district team had not yet been established. In the district where the first community district team was established most primary target patients were treated. In cross-section II the hospital-based psychiatric service were more homogeneously distributed between the districts. The establishment of community-based psychiatric teams resulted in new referrals, and increasing numbers of patients becoming attached to the psychiatric teams, but crowding and use of compulsory measures in hospital also increased.     

Increased availability and open probability of single L-type calcium channels from failing compared with nonfailing human ventricle

BACKGROUND: The role of the L-type calcium channel in human heart failure is unclear, on the basis of previous whole-cell recordings. METHODS AND RESULTS: We investigated the properties of L-type calcium channels in left ventricular myocytes isolated from nonfailing donor hearts (n= 16 cells) or failing hearts of transplant recipients with dilated (n=9) or ischemic (n=7) cardiomyopathy. The single-channel recording technique was used (70 mmol/L Ba2+). Peak average currents were significantly enhanced in heart failure (38.2+/-9.3 fA) versus nonfailing control hearts (13.2+/-4.5 fA, P=0.02) because of an elevation of channel availability (55.9+/-6.7% versus 26.4+/-5.3%, P=0.001) and open probability within active sweeps (7.36+/-1.51% versus 3.18+/-1.33%, P=0.04). These differences closely resembled the effects of a cAMP-dependent stimulation with 8-Br-cAMP (n= 11). Kinetic analysis of the slow gating shows that channels from failing hearts remain available for a longer time, suggesting a defect in the dephosphorylation. Indeed, the phosphatase inhibitor okadaic acid was unable to stimulate channel activity in myocytes from failing hearts (n=5). Expression of calcium channel subunits was measured by Northern blot analysis. Expression of alpha1c- and beta-subunits was unaltered. Whole-cell current measurements did not reveal an increase of current density in heart failure. CONCLUSIONS: Individual L-type calcium channels are fundamentally affected in severe human heart failure. This is probably important for the impairment of cardiac excitation-contraction coupling.     

The problem of Q fever in zoo ungulates]

Antibodies to Coxiella burnetii were recorded from approximately 13% of 469 ungulates which had been examined by means of micro-CFT (complement fixation test). Particular reference is made to a Q-fever situation in a musk ox herd. The results obtained from these investigations are likely to support the conclusion that latent Q-fever infection may be expected to occur in ungulates and to grow manifest in stress situations.     

Attentional orienting and reorienting is indicated by human event-related brain potentials

We investigated event-related potential indications for the orienting towards task-irrelevant, distracting aspects of stimulation and for the subsequent reorienting towards task-related aspects of stimulation. An identical experimental protocol was run in three conditions manipulating the task relevance of the sounds. As to be expected, distractors elicited the MMN (reflecting the brain's pre-attentive change detection) in each condition (even when the sounds were ignored) and subsequent N2b and P3 (reflecting orienting towards the distractor) when the sounds were attended. A late negativity was confined to a condition in which subjects discriminating long from short sounds were distracted by task-irrelevant frequency deviations. The 'reorienting negativity' (RON) probably reflects processes in the context of reorienting towards task-relevant aspects of stimulation following distraction.     

Impact of early operation on the mortality from bleeding peptic ulcer --ten years'' experience

An experimental protocol was tested to measure elastic properties of connective tissue displaying viscoelastic as well as plastic properties. The protocol consisted of a slow rate, linear elongation (0.88 mms(-1), 8 mm) in combination with a superimposed sinusoidal vibration of small amplitude (50 Hz, 0.1 mm). Using digital filters and mathematical algorithms, the force responses to linear elongation and to vibration were obtained. The method was tested on excised fibromuscular tissue of the vaginal wall obtained from women who suffered a vaginal prolapse. The force-stiffness and force-elongation relationships based on the vibration response were unaffected by any long-term deformation of the specimens. The directly measured force-elongation curves were strongly affected by these deformations. It was therefore concluded that with the new method, it is possible to determine the elastic properties accurately. Furthermore, this method seems more sensitive to small changes in elastic properties than the classic tensile test.     

The Theory of Zero-Suppressed BDDs and the Number of Knight's Tours

Zero-suppressed binary decision diagrams (ZBDDs) have been introduced by Minato [14–17] who presents applications for cube set representations, fault simulation, timing analysis and the n-queens problem. Here the structural properties of ZBDDs are worked out and a generic synthesis algorithm is presented and analyzed. It is proved that ZBDDs can be at most by a factor n + 1 smaller or larger than ordered BDDs (OBDDs) for the same function on n variables. Using ZBDDs the best known upper bound on the number of knight's tours on an 8 × 8 chessboard is improved significantly.     

Interphase cytogenetics of prostatic tumor progression: specific chromosomal abnormalities are involved in metastasis to the bone

Only limited data are available on chromosomes specifically involved in the multistep tumorigenesis of prostate cancer. To investigate the cytogenetic status at different stages of prostatic tumor development, we have applied interphase in situ hybridization (ISH) with a set of (peri) centromeric DNA probes--specific for chromosomes 1, 7, 8, and Y--to routinely processed tissue sections of prostatic specimens from 75 different individuals. Our panel consisted of: 16 normal/benign prostatic hyperplasia specimens; 23 primary, localized, prostatic tumors (N0M0 stage); 20 regional lymph node metastases (M0 stage); and 16 distant metastases. Numerical aberrations of at least one chromosome were not observed in normal/benign prostatic hyperplasia cases, but were present in localized tumors (39%), regional lymph node metastases (40%), and distant metastases (69%). Within the different pTNM groups, we observed the following aberrations (listed, within each series, in decreasing order of frequency): -Y, +8, -8, +7 in primary tumors; +8, +7, -Y, +Y, -8 in regional lymph node metastases; and +8, +7, +1, -Y, -8 in distant metastases. In primary tumors, the number of aberrant cases increased significantly with local tumor stage (p < 0.05). A significant increase in gain of chromosome 8 was also observed (p < 0.02). Gain of chromosome 7 and/or 8 showed a significant increase with progression of local tumor stage (p < 0.02). Specific involvement of chromosome 8 was seen in bone metastases, but not in hematogenous metastases to other sites (p = 0.02). Comparative genomic hybridization analysis of these bone metastases disclosed centromere 8 gains as amplifications of the (whole) 8q arm, whereas centromeric loss appeared to be due to loss of 8p sequences. With progression toward metastatic disease, an accumulation of genetic changes was seen as exemplified by gain of chromosome 1, which was solely observed in distant metastases. With tumor progression, gain of chromosomes 7 and/or 8 significantly increased (p = 0.03), whereas the number of cases with aberrations of the Y chromosome did not change. Furthermore, ploidy status determined by ISH revealed a significant increase in the number of aneuploid cases along with advancement of pTNM stage (p = 0.04). Collectively, the data strongly suggest that: (a) gain of chromosome 7 and/or 8 sequences is implicated in prostatic tumor progression; (b) gain of chromosome 8 sequences is related to local tumor growth; (c) overrepresentation of 8q sequences, most likely by isochromosome 8q formation, is involved in metastatic spread to the bone; and (d) changes in the centromeric copy number, as detected by interphase ISH, might in some cases represent structural alterations, such as an isochromosome.