EFFECT OF PREHYDROGENATION ON HYDROCONVERSION OF MAYA RESIDUUM, PART I: PROCESS CHARACTERIZATION

Maya 650°F residuum was mildly prehydrogenated over a standard, commercially available, hydrodesulfurization catalyst. The product was then distilled to yield hydrogenated Maya 650°F residuum. This prehydrogenated residuum, and the untreated Maya 650°F residuum were separately hydroprocessed further at different process severities. The resulting products were then examined by elemental analyses to determine the effects of die prehydrogenation step on overall conversion and product quality.

The primary effect of the prehydrogenation step was to increase the overall conversions for sulfur, MCR, nitrogen, and asphaltenes. As a result, the hydro-conversion products derived from the prehydrogenation were substantially better quality than the corresponding direct hydroconversion products. The prehydrogenation step also lowered the severity required for equivalent residuum hydroconversion upgrading.     

Individual variation for cognitive decline: Quantitative methods for describing patterns of change.

What are the best quantitative methods for studying cognitive decline? This question was investigated in a sample of 638 individuals aged 50 years and older from the Swedish Adoption/Twin Study of Aging. A battery of cognitive tests tapping multiple domains was administered to each individual from 2 to 7 times over a span of 10 years. Four methods of operationalizing cognitive decline were compared: change scores, a criterion-based method, least squares, and random effects regression (RER). The RER results were most consistent with a significant decline across measures and differences between demented and nondemented individuals. Predicted slopes from the RER model also showed the strongest interrelationships within and across cognitive domains as indicated by factor analysis results and stronger associations with demographic, health, and psychosocial predictors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Signalling regions: Multiprocessing in a shared memory reconsidered

The goal of this paper is to return attention to two problems that arise in the context of supporting the monitor as a mechanism for concurrent programming. This paper will re-examine the monitor concept in its original context—a multiprocessing environment implemented on a single processor sharing memory with and being interrupted by asynchronous peripheral devices—and will address the two previously unresolved problems. The first is the conflict between the immediate resumption requirement in explicit signalling and the policies and priorities of the process scheduler. The second is the possibility of deadlock inherent in nested monitors and in its most important instance, the dynamic resource allocation problem. After briefly describing the historical context of these two problems, the paper proposes a language structure called a signalling region that together with the notion of encapsulation by modules solves the immediate resumption problem and avoids the nested monitor problem. The former is done by a combination of the signal-and-return semantics of Concurrent Pascal and the signal-and-continue semantics of Mesa and StarMod. The latter is done by suggesting that mutual exclusion and data encapsulation are distinct concepts that, if separated, make nested encapsulation possible while avoiding the problems of nested mutual exclusion. Classical examples of the use of signalling regions in an extended Modula-2 are given as well as an implementation by translation to unextended Modula-2 together with a Kernel module.     

Lack of effect of food on the steady state pharmacokinetics of BMS-181101, an antidepressant, in healthy subjects

An annual atmospheric pollen survey was performed for 14 consecutive years in the autumn at Sakado city, Saitama prefecture. The survey was performed on the transition of pollen dispersion of major allergen plants: ragweed (Ambrosia spp.), Humulus japonicus, Artemisia spp. and Gramineae. 1. Annual total pollen count of ragweed showed marked increases beginning from 1991. Total pollen count in 1991 was 8.8 times and that in 1996 was 18.6 times that in 1983. This increase is probably caused by marked proliferation of giant ragweed which is left without mowing as it is on a dry riverbed, and consequently produces much more pollen than short ragweed. 2. Annual increases in total pollen counts of other major plants which disperse their pollen in the same season as ragweed were 0.95 times in 1991 and 0.5 times in 1996 that in 1983 for Humulus japonicus, 0.68 times in 1991 and 1.5 times in 1996 that in 1983 for Artemisia spp. and 1.3 times in 1991 and 1.4 times in 1996 that in 1983 for Gramineae. None of these species showed a marked increase of pollen dispersion although they showed some annual variation. The above findings suggest that changes in the proliferous state of various allergenic plants due to environmental change should be considered with respect to characteristics of pollen allergy.     

Frequency/voltage convertor with low output ripple

A circuit is desdribed which performs linear frequency-to-voltage conversion with nominally zero output ripple and, at one frequency, ideal step response. This is in contrast to conventional convertors which have large output ripple, the removal of which necessarily produces slow response.     

p53 and K-ras status in duodenal adenomas in familial adenomatous polyposis

BACKGROUND: The genetic alterations in patients with familial adenomatous polyposis (FAP) and duodenal adenomas are poorly characterized when compared with data relating to colorectal tumorigenesis in the same patients. METHODS: Point mutation of the K-ras oncogene and point mutation and overexpression of the TP53 tumour suppressor gene were investigated in 32 duodenal polyps (seven without mucosal pathology, 23 with mildly dysplastic adenomas and two with moderately dysplastic adenomas) from 21 patients with FAP. RESULTS: K-ras mutation, TP53 mutation or positive p53 staining were not found in duodenal polyps without histological abnormality. Of 25 duodenal adenomas, K-ras mutation was found in three (two mildly dysplastic, one moderately dysplastic), 20 showed positive p53 immunostaining, and mutation of the TP53 gene was found in one moderately dysplastic adenoma. p53 protein overexpression in duodenal adenomas was significantly more frequent than mutation of either K-ras or TP53 (P < 0.01). CONCLUSION: p53 dysfunction is a hallmark of duodenal adenomas in patients with FAP. Overexpression may indicate DNA damage and thus an early step in tumorigenesis.     

Molecular cloning, cDNA sequence analysis, and chromosomal localization of mouse Pkd2

The gene responsible for the second form of autosomal dominant polycystic kidney disease, PKD2, has recently been identified. We now describe the cloning, genomic localization, cDNA sequence, and expression analysis of its murine homologue, Pkd2. The cloned cDNA sequence is 5134 bp long and is predicted to encode a 966-amino-acid integral membrane protein with six membrane-spanning domains and intracellular NH2 and COOH termini. Pkd2 is highly conserved with 91% identity and 98% similarity to polycystin-2 at the amino acid level. Pkd2 mRNA is widely expressed in mouse tissues. Pkd2 maps to mouse Chromosome 5 and is excluded as a candidate gene for previously mapped mouse mutations resulting in a polycystic kidney phenotype.     

Development of male contraceptive vaccine--a perspective

Anti-disialoganglioside (GD2) monoclonal antibodies (MAbs) have been used in vivo for immunolocalization and in phase I and II trials to target disseminated neuroblastoma, the most common extracranial solid tumor in children. However, the efficacy of these first-generation MAbs is likely to be improved by using engineered anti-GD2 antibodies. The generation of single-chain antibody fragments (scFv) could be very helpful as these molecules can be further modified to produce recombinant molecules with pre-defined properties such as immunotoxins, chimeric, or bispecific antibodies. Thus, a scFv directed against GD2 (scFv 7A4) was cloned, sequenced, and expressed. Its binding properties were characterized and compared to that of the parental MAb 7A4. Nucleotide sequence analysis of the scFv 7A4 indicated that its VH region belongs to the V region IIID subgroup and the V kappa to the V region II subgroup. The scFv 7A4 bound to GD2+ neuroblastoma cell lines but not to GD2- cell lines or to GD2- cells isolated from peripheral blood. ELISA and thin-layer chromatography (TLC) indicated that it retained the anti-GD2 specificity, and exhibited a slight cross-reaction with GD3 as the parental MAb. This scFv makes it possible to develop new useful reagents through genetic engineering for adjuvant tumor therapy.     

Psychological predictors of pain during dental hygiene treatment

This study examined the role of catastrophizing (i.e. a tendency to exaggerate the threat value of potentially painful situations) in predicting pain experience during dental hygiene treatment. Participants in the research were 100 patients undergoing scaling and/or root planing procedures at Dalhousie University's Dental Clinic. Following treatment, participants completed the Pain Catastrophizing Scale, a measure of emotional distress, a pain scale, and the Dental Anxiety Scale-Revised. Participants who scored above the median on the Pain Catastrophizing Scale were classified as catastrophizers, participants who scored below the median were classified as noncatastrophizers. Results showed that catastrophizers reported significantly more dental anxiety, emotional distress and pain than noncatastrophizers; and that distress reactions were more pronounced in men that in women. Discussion focuses on the importance of addressing psychological factors in dental hygiene practice, particularly as they relate to reactions to dental hygiene procedures, and avoidance of dental care.     

Long-term outcome in acute myocardial infarction patients admitted to hospitals with and without on-site cardiac catheterization facilities. MITI Investigators. Myocardial Infarction Triage and Intervention

BACKGROUND: Previous studies have documented the strong association between availability of on-site cardiac catheterization facilities and increased use of coronary angiography in patients with acute myocardial infarction (AMI). Although these studies have shown little influence of the availability of catheterization labs on hospital mortality, no long-term follow-up has been reported. METHODS AND RESULTS: From a cohort of 12,331 AMI patients admitted to 19 Seattle area hospitals, we compared long-term outcome in 7985 patients admitted to hospitals with and 4346 patients admitted to hospitals without on-site catheterization labs. During the index hospitalization, patients admitted to hospitals with on-site catheterization were more likely to undergo coronary angiography (67.1% versus 39.3%, P<.0001), coronary angioplasty (32.5% versus 13.2%, P<.0001), or coronary bypass surgery (12.5% versus 9.5%, P<.0001). At 3-year follow-up, patients admitted to hospitals with on-site catheterization labs were more likely to undergo postdischarge angiography (19.2% versus 15.2%, P=.0001) and coronary angioplasty (11.6% versus 8.2%, P<.0001). This was associated with approximately $2500.00 per patient in higher cumulative costs. Despite this higher rate of procedure use, there was no association between admission to a hospital with on-site catheterization facilities and lower long-term mortality (multivariate hazard ratio, 1.0; 95% CI, 0.93 to 1.1., the hazard being associated with admission to hospitals with on-site catheterization facilities). CONCLUSIONS: In an urban area with unconstrained patient transfer mechanisms and high overall cardiac procedure use rates, AMI patients admitted to hospitals without on-site catheterization facilities were managed with fewer procedures during hospitalization and follow-up. This more conservative treatment approach was not associated with any observed increase in long-term mortality.