Genetic transmission of major affective disorders: Quantitative models and linkage analyses.

We comprehensively reviewed 2 types of studies aimed at specifying the mode of inheritance of major affective disorders: quantitative models and linkage analyses. Quantitative models attempt to represent the genetic mechanism responsible for the familial distribution of a disorder. Despite efforts to refine models by incorporating the bipolar–unipolar distinction or the sex effect, consistent support for a specific mode of transmission has not been found. Some mixed genetic models support single major locus inheritance, but transmission probabilities do not conform to Mendelian expectations. Linkage analysis is a more powerful technique used for testing the single gene hypothesis. Linkage results have also been inconsistent, showing moderate support for an X-linked variant of bipolar-related disorder and equivocal support for linkages to Chromosomes 6 and 11. However, relatively few genetic loci have been examined. Methodological factors, genetic heterogeneity, and phenotypic heterogeneity are discussed as potential explanations for inconsistent findings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Grinding of titanium alloys by Elbor and diamond wheels

The grinding of titanium alloys by Elbor and diamond wheels with ceramic and organic binders is analyzed. There is considerable scope for increasing the efficiency of grinding.     

The paradox of normal neuropsychological function in schizophrenia.

Mounting evidence suggests that compromised neurocognitive function is a core feature of schizophrenia. However, some studies have found neuropsychologically normal schizophrenia patients. To address this apparent contradiction, we blindly rated individual neuropsychological profiles of 75 schizophrenia patients and 91 control participants on the basis of methods developed by L. J. Seidman, S. V. Faraone, W. S. Kremen, J. R. Pepple, M. J. Lyons, and M. T. Tsuang (1993). Almost one-quarter of the patients were classified as neuropsychologically within normal limits (WNL). Despite significantly worse neuropsychological performance, WNL patients had higher estimated premorbid ability than did controls. Compared to a subset of controls matched on overall neuropsychological function, WNL patients had higher estimated premorbid ability and current IQs. Our results favor the view that even neuropsychologically normal schizophrenia patients have compromised cognitive function relative to their presumed expected or premorbid level of intellectual ability. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Model demonstrating the potential for coupled nitrification denitrification in soil aggregates

A model of reactive, multi-species diffusion has been developed to describe N transformations in spherical soil aggregates, emphasizing the effects of irrigation with reclaimed wastewater. Oxygen demand for respiratory activity has been shown to promote the establishment of anaerobic conditions. Aggregate size and soil respiration rate were identified as the most significant parameters governing the existence and extent of the anaerobic volume in aggregates. The inclusion of kinetic models describing mineralization, nitrification, and denitrification facilitated the investigation of coupled nitrification/denitrification (CND), subject to O2 availability. N-transformations are shown to be affected by effluent-borne NH4+-N content, in addition to elevated BOD and pH levels. Their incremental contribution to O2 availability has been found to be secondary to respiratory activity. At the aggregate level, significant differences between apparent and gross rates of N-transformations were predicted (e.g., NH4+ oxidation and N2 formation), resulting from diffusive constraints due to aggregate size. With increasing anaerobic volume, the effective nitrification rate determined at the aggregates level decreases until its contribution to nitrification is negligible. It was found that the nitrification process was predominantly limited to aggregates <0.25 cm. Assuming that nitrification is the main source for NO3- formation, denitrification efficiency is predicted to peak in medium-sized aggregates, where aerobic and anaerobic conditions coexist, supporting CND. In effluent-irrigated soils, the predicted NO2- formation rate in small aggregates is enhanced when compared to freshwater-irrigated soils. The difference vanishes with increasing aggregate size as anaerobic NO2- consumption exceeds aerobic NO2- formation due to the coupling of nitrification and denitrification.     

A method for magnetic inspection of layered structures

A three-layer structure is studied with a computer model. The magnetization of any layer was shown to be determined by both its magnetic properties (the basic magnetization curve) and the magnetic properties of the other layers and core. The informative (secondary) magnetic field at any point of space was found to contain complete information on the parameters of each layer. A new procedure allowing the information to be available is suggested. On this basis, a method for the magnetic inspection of layered structures is developed.     

Neuropsychological functioning among the nonpsychotic relatives of schizophrenic patients: A 4-year follow-up study.

In a prior study of 54 relatives of patients with schizophrenia and 72 control participants, 3 neuropsychological functions met the criteria for risk indicators of the schizophrenia genotype: executive functioning, memory, and auditory attention. In an assessment of the stability of these findings, the sample was reexamined 4 years after the initial assessment. Three test scores were found to differ between groups (Immediate Verbal Memory, Delayed Verbal Memory, and Dichotic Listening Digits Detected) or to show a significant Group?×?Gender interaction (immediate and delayed verbal and visual memories). None of the test scores showed Group?×?Time interactions, suggesting that the discriminating power of the tests was stable over time. Evidence for deficits in working memory and rule learning on the object alternation test was also found. These results support the idea that neuropsychological dysfunction among relatives of patients with schizophrenia is a stable trait caused by the familial predisposition to schizophrenia. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Means by which reverse osmosis desalting costs can be substantially reduced well. before the year 2000

Examination of the market, state-of-the-art in current practice, and a well documented recent study agree on cost for sea water desalting by reverse osmosis which is approximately $4.00 per thousand gallons of purified water produced. At this cost one generally only produces, reliably, water to meet the rather lenient purity standard of less than 1000 mg/l total dissolved solids after demineralization and conditioning if the recovery fractions and membrane replacement frequency are to have any degree of respectability and acceptability. The study predicts that future “fully developed costs” will be approximately $1.00 per thousand gallons of purified water, largely on the basis of a substantial investment in time and money for research and development over a period of many years.

The thrust of this paper is that present technological product, process, and engineering capability can be used in high recovery full two-stage systems to reduce these costs by 40% to approximately $2.60 per thousand gallons of purified water produced, with such conditioned water meeting the 500 mg/1 TDS and the 250 mg/1 chloride ion upper limits. This thesis is examined and illustrated in detail in several iterations, including sea waters containing 35,000 and 42,000 mg/1 TDS respectively. The above approach produces substantial savings in power requirements, membrane replacement and pre-treatment capital and operating costs which far outweigh the added capital amounts to be amortized. These improvements can be realized starting now with minimum development cost or effort. Further cost reductions to be achieved thereafter by research and development effort are also considered.     

Experimental and clinical neuropsychological measures of prefrontal dysfunction in schizophrenia.

Eighteen chronic schizophrenia patients and 14 controls were given tests that have been linked primarily to ventral (orbitofrontal) or to dorsolateral prefrontal dysfunctions in neurological patients and in nonhuman animal Ss having discrete frontal lesions. Schizophrenia patients were significantly impaired on object alternation and delayed alternation tasks but not on classical delayed response (DR). Schizophrenia patients performed well on the classical version of the DR task and their DR performance correlated significantly with measures of sustained attention. Future research is needed to interpret the contributions of attention, interference, and memory load to neuropsychological performance in schizophrenia. Additional studies are required to determine whether the frontal deficits reflect diffuse brain damage, circumscribed prefrontal damage, or damage in other brain regions having prefrontal connections. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Sex differences in neuropsychological function in non-psychotic relatives of schizophrenic probands

Some recent studies suggest that men with schizophrenia may have greater neuropsychological deficits than women. It is not known, however, whether similar sex differences may be present in biological relatives of schizophrenic patients. We evaluated neuropsychological functioning of 54 relatives of schizophrenic patients and 72 normal volunteers. It was hypothesized that, if sex differences were present, they would be accounted for largely by deficits in male relatives. We were particularly interested in three neuropsychological functions that we previously identified as putative neuropsychological vulnerability indicators for schizophrenia: (1) abstraction/executive function; (2) verbal memory; and (3) auditory attention. There were significant group x sex interactions for verbal memory and motor function, and trends toward significant interactions for auditory attention and mental control/encoding. However, with the exception of motor function, it was the female relatives who accounted for most of the impairment. A speculative explanation for the findings is that women may have a higher threshold than men for developing schizophrenia. If so, female relatives might be able to withstand greater impairments than men before developing psychotic symptoms. Consequently, in a sample that was limited to non-psychotic relatives--as in the present study--there could be over-representation of both less impaired men and more impaired women. Alternative explanations and limitations of the study are also discussed.     

Correlates of psychosis proneness in relatives of schizophrenic patients.

The Magical Ideation Scale (MIS), Perceptual Aberration Scale (PABS), Social Anhedonia Scale (SAS), and Physical Anhedonia Scale (PAS) were administered to 98 relatives of schizophrenic patients along with a measure of personality disorders (the Personality Diagnostic Questionnaire—Revised). Hierarchical regression analysis indicated that the schizotypal and borderline personality disorder (PD) scales explained significant variance in both the MIS and PABS; the avoidant PD scale also explained significant variance in the PABS. The schizoid, paranoid, and avoidant PD scales explained significant variance in the SAS. Sibling intraclass correlations indicated a significant heritability of 0.62 for the PABS. (PsycINFO Database Record (c) 2010 APA, all rights reserved)