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Linear stability theory for Rayleigh-Benard convection shows that for a specified Rayleigh number, greater than some critical value, only a finite range of horizontal wave numbers support convective instability in a horizontal layer of fluid heated from below. However, it is not possible to predict the preferred horizontal scale of established motions from this approach although it is clear from observations, particularly of the solar surface, that a preferred cell size does prevail. In an endeavour to establish a preferred horizontal scale appropriate non-linear modal equations have been integrated forward in time, initially incorporating a discrete band of wave numbers equally spaced across the range that supports convection, for a specific Rayleigh number. The horizontal resolution was improved in subsequent integrations by first deleting modes that had substantially decayed and then introducing new modes on a finer horizontal mesh in the vicinity of what appeared to be the evolutionary dominant mode. Finally, the multimode integrations were continued in time until the evolution of a dominant horizontal mode from within the restricted range was evident. Both the model characteristics and numerical scheme adopted placed limits on the degree of horizontal refinement that could be undertaken with confidence.

In the past five years, routine CEA determinations have been carried out on all patients after curative operation for colorectal carcinoma. These patients also underwent a clinical follow-up examination in the Oncology Outpatient Department. In 86 patients, recurrence of a tumor was confirmed. In 31 cases, a second-look operation was carried out. The CEA determinations were retrospectively analyzed in these patients and correlated with the time the recurrence of the tumor was diagnosed. These results show that of 86 patients only 15 (17.4 per cent) had pathologic CEA values before clinical symptoms of tumor recurrence. In the patient group with local recurrence only 11 (23.9 per cent) of 46 patients had previously pathologically raised CEA values. Of 31 patients, 15 (48.4 per cent) underwent curative resection after the second-look operation. At this time, 12 patients (38.7 per cent) still had normal CEA values, whereas only three patients (9.7 per cent) had pathologically raised CEA values. From these results, it was established that early diagnosis of tumor recurrence was very low. Therefore, one should not rely more on postoperative routine CEA determinations in the post-operative monitoring of patients following curative operations for colorectal carcinoma than on regular comprehensive follow-up examinations of these patients.

This report provides a detailed analysis of the methods employed in our laboratory for the growth and maintenance of functional monolayer cultures of murine adrenal tumor cells. Radiochemical analysis of the products of incubation of these cells with 3H-pregnenolone, 14C-progesterone, and 14C-sodium acetate has confirmed that the predominant steroids secreted into the medium are 20α dihydroprogesterone and 11β hydroxy, 20α dihydroprogesterone. Chemical and enzymatic procedures for the synthesis of the latter compound and other 20α hydroxylated steroids are described. A fluorometric assay has been developed that permits precise quantitation of steroid output within several minutes' incubation. Consistent Steroidogenic responses to ACTH ranging as high as ten times the basal output have been observed. There is a linear log-dose response to ACTH (or Synacthen, a β1–24 peptide fragment of ACTH) ranging from 10 pg/ml to 1000 pg/ml. A variety of other peptide hormones were found to be inactive. The response to ACTH proceeds linearly from 10 min to 24 hr. These cells provide a viable and highly reproducible system for the in vitro study of ACTH action.

Single crystals of 99.999% purityβ-tin grown from the melt were shown by X-ray topography to contain dislocations with Burgers vectors of [001] type and of 1/2〈111〉 type. Specimen plates cut roughly parallel to (311) were chemically thinned from 1.25 mm to 100μm thickness and in two cases characteristic dislocation structures were generated at their surfaces. A specimen thinned in concentrated HCl possessed stress-producing centres distributed on its surfaces with a density of about 75 mm−2 from which regular helices and coaxial prismatic loops with [001] Burgers vector were generated together with irregular loops of 1/2〈111〉 Burgers vector dislocations. In one specimen thinned in a H3PO4, CH3COOH, HF and HNO3 mixture large arrays of pure edge dislocations grew parallel to the surface at a depth of 2 to 4μm below it, the individual dislocations extending at about 1μm h−1 during several weeks. These edge arrays all had that one of the four 1/2〈111〉-type Burgers vectors which made the smallest angle (5°) with the surface. The Burgers vector sense, determined by X-ray diffraction contrast, corresponded to a sheet of vacancies lying between the dislocation line and the surface.

Two emission spectrometers, a modified Hilger Watts-quartz spectrograph and a commercially available N15-analyser (type NO1-4) were tested with standard gas samples, whose N15-contents in the range of natural (0.365%) to about 80% N15 abundance were also determined by mass-spectrometry. Both optical instruments make use of the isotope effect in the electronic-vibrational spectrum of nitrogen in the far ultra-violet. Sample preparation has to be carefully considered. The total amount of nitrogen required to determine easily a N14/15 ratio by the emission spectrographic method is only about 10 µg. This corresponds to a total weight of plant material of under 1 mg and at this level homogeneity questions are very important. It is necessary to use a sample of at least 100 mg to reduce uncertainty due to inhomogeneity to well under the levels of field agricultural variation (±5%). With this quantity of sample, both the Kjeldahl method (followed by the Rittenberg conversion of ammonium to nitrogen) and the dry Dumas method are equally satisfactory.

The plastic zone around the fatigue crack in copper single crystals was studied by means of transmission electron microscopy and x-ray topography. These methods made it possible t o observe dislocation sub-structure typical for the plastic zone as well as to determine the shape and size of the plastic zone and their depondence on tho crack length.

An automatic analyser is used for the measurement of total nitrogen in chemical compounds and botanical material after the combustion method of Dumas in vacuum. The analyser is described and results for several chemical compounds and plant materials are given. The results have been statistically evaluated to compare the reproducibility and accuracy of the automatic analyser and the Kjeldahl method.

The paper describes “tails” and side-bands observed on the diffraction patterns of samples after diffusion heating. The origin of “tails” is explained by the presence of vacancy clusters. Side-bands on X-ray patterns of an Au-Pt sample are interpreted in terms of a pre-precipitate structure or of a metastable phase in the region rich in gold.

The diffusion zone of a sample in the form of three layers was studied by electron microscopy, X-ray diffraction, light microscopy and microhardness test. Experimental results clearly show that in the diffusion zone there is a superposition of thermal stress and a stress due to the vacancies.

CF0CF1 was isolated from chloroplasts of the cell wall-deficient Chlamydomonas reinhardtii strain cw15. The subunit pattern was analyzed by SDS-gel electrophoresis and the N-terminal amino acid sequences of all nine subunits were determined by microsequencing. The amino acid sequences of subunits alpha, beta, gamma and epsilon match with those derived from the corresponding Chlamydomonas DNA sequences. In variance with the previously assumed N-terminus of beta; however, it was found that the first 11 amino acids are lacking. The subunits delta, I, II, III and IV were identified by comparison with known sequences of homologous polypeptides of higher plant chloroplasts and cyanobacteria, respectively.

We produced atpA and atpB deletion mutants of C. reinhardtii cw15 in order to investigate the role of certain domains of the α and β subunits of the chloroplast ATP synthase (CF 0 CF 1 ) by site-directed mutagenesis. The deletion mutants were obtained by transformation with constructs containing the aadA cassette inserted into the atpA or atpB genes in place of the corresponding open reading frames. Homoplasmic strains were obtained by continued selection under heterotrophic growth conditions in the presence of spectinomycin. The deletion mutants could be complemented by transformation with the wild-type atpA or atpB genes, respectively. In both deletion mutants none of the subunits of CF 1 and of CF 0 were detected by electrophoretic analysis. Since the mother strain cw15 as well as the deletion mutants are cell wall-deficient, we were able to prepare photosynthetically active thylakoids and to study the photosynthetic characteristics of cw15 thylakoids and mutant thylakoids lacking the ATP synthase. Electron transport measurements showed that the PSII and PSI activities were not affected in the deletion mutants. Thylakoids from the deletion mutants were able to maintain a significantly higher light-induced proton gradient than thylakoids from cw15, confirming the absence of a functional proton channel in these deletion mutants. When substrates of photophosphorylation were added, the transmembrane proton gradient in wild-type thylakoids decreased and ATP was formed, while in the deletion mutant thylakoids the proton gradient was not affected and no ATP was formed. The phosphorylation/ Δ pH relationship in C. reinhardtii thylakoids was shifted to lower Δ pH values by reduction with dithiothreitol, indicating that the C. reinhardtii enzyme is also similar to the higher plant chloroplast ATP synthase in this respect.

A method is suggested, using diffraction line displacements, to facilitate simultaneous determination of one-dimensional strain in a particular direction in the surface of a polycrystalline material and of the lattice parameter corresponding to the unstressed state. A single exposure at perpendicular incidence of the primary X-ray beam enables both values to be obtained. Full advantage is taken of the ratios of diffraction ring diameters.

After a 3- and 8 day administration of cyclophosphamide to rats an approximately dose-dependent decrease in the pancreatic secretion of protein and enzyme activities was demonstrable in vivo under exogenous stimulation with secretin and pancreozymin. The volume of secretion and the electrolyte outputs were found to be slightly lowered. An impairment in enzyme synthesis resulting from cyclophosphamide administration is suggested as the major cause of the observed changes in secretion.

A major barrier to the conduct and interpretation of retrospective studies of diet and cancer has been uncertainty about the reliability of retrospective measures of diet from the distant past. The authors therefore conducted a study to assess the reliability of retrospective dietary reports and to determine whether the retrospective report or the report of current diet is the better indicator of past diet. Persons (n = 323) originally interviewed regarding their diets in 1975-1979 were retrospectively reinterviewed in 1984-1985. There was little difference between the retrospective reports and the reports of current diet when group means were examined as indicators of past diet. The retrospective reports tended to overestimate the past frequency of consumption for most foods, whereas the reports of current diet tended to yield underestimates. Because food frequency-based dietary history data are more useful for ranking study subjects than for generating estimates of group means, correlation analysis was used as the principal assessment of the reliability of the two indicators of past diet. The retrospective reports more closely correlated with the diet reported at the original interview than did the report of current diet (for 37 of 47 foods). Nutrient indices based on the retrospective history were also more highly correlated with those of the original diet than were indices based on the current diet. No differences were noted in the reliability of retrospective reports according to age or sex. Subjects accurately reported perceptions of changes in their consumption of most foods, yet an estimate of past diet created by adjusting current diet for perceived change did not correlate more highly with the original diet than did the retrospective report. The authors conclude that assessing current diet to make inference about diet from the distant past does not yield more reliable estimates of past diet than does the retrospective dietary history. The best estimate of diet from several years in the past may be derived directly from a retrospective dietary history which focuses on that past period of time.

The School of Health Related Professions (HRP) at State University of New York at Buffalo offers its volunteer clinical faculty (VCF) a number of benefits and privileges. These VCF are professionals who train students but do not receive monetary compensation for doing so. A study was conducted to determine what benefits/privileges are valued and used most, the impact and use of tuition waivers (TWs), and other benefits the VCF would desire. A survey was sent to 383 VCF, and 233 (61%) responded. The results showed that VCF valued, in order of priority: TWs, University library privileges, faculty parking, photocopying service, clinical faculty awards, use of recreational facilities, and faculty discounts. The data revealed that 42% of the respondents had used TWs, and the study demonstrated that TWs promote the University's graduate programs. The data supported the contention that TWs play a significant role in recruiting and rewarding VCF. As a result, University financial support for TWs was not eliminated. The feasibility and cost of implementing other incentives for VCF participation, suggested by the VCF, will be investigated by the School of HRP in the future.

Daily flux density measurements of compact extragalactic radio sources using the Green Bank interferometer (36 sources)1 and the NRAO 300ft antenna (340 sources)2 reveal several unusual variations in the light curves that do not follow typical source variations. Unusual variations have been identified in the light curves of eight quasars. Refractive effects involving small‐scale inhomogeneities in an ionized structure in the interstellar medium seem to most likely explanation for the unusual variations observed.

Verschiedene Entwicklungen erschweren es dem Controller, den Uberblick uber sein Zahlenmaterial zu behalten. So erhoht sich allmahlich die Zahl der DV-Systeme, die einschlagige Listen und Tabellen ausgeben, wir erleben die Ausdifferenzierung in Fertigungs-, Vertriebs-, Logistik-Controlling usw.

The influence on the specific cell-mediated immunity (CMI) of the carcinoma of the prostate gland by the contra-sexual hormone therapy with Cytonal, Estrazyt and Turisteron is controlled. For this purpose the macrophage-electrophoresis-mobility test on the basis of allogenic tumour-associated antigen of the carcinoma of the prostate gland is used. As a result the use of Cytonal at least in the dosage hitherto used is no longer worth being advocated. Turisteron and Estrazyt, respectively, taking into consideration their pharmacokinetics and indication, prove to be immunologically optimal and without hesitation, respectively. Turisteron is the basic therapeutic in the androgen-dependent carcinoma of the prostate gland. Estrazyt should be reserved to primarily and secondarily hormone-refractory tumours. For the application of Estrazyt an additive immune stimulation seems to be worth taking into consideration.

Two curricular approaches for modifying nonhandicapped high school students' attitudes toward their exceptional peers were compared. One curriculum was structured around categories of exceptionality (e.g., mental retardation, sensory impairments) while the other focused on generic concepts, including values, conformity, individual differences, and labeling effects. Each curriculum was presented over a 10-week period and the effects assessed via two pencil-paper attitude evaluation scales. Results revealed that both curricula positively modified students' attitudes, with subjects exposed to the categorical curriculum demonstrating significantly greater attitude changes. The data are interpreted relative to the issue of labeling and the most effective means of positively modifying attitudes toward handicapped persons.

An updated version of a 9-item questionnaire concerning misconceptions about mental retardation originally developed by Winthrop and Taylor (1956) was administered to a total of 558 individuals from heterogenous samples. The relations of the demographic, experimental, and contact characteristics of the respondents in the 1986 sample to their misconceptions score were explored as were differences in the distributions of the percentages of endorsements of the nine misconceptions for the samples in 1956 and 1986.

This report describes the appearance of thyrotoxicosis over the past eight years in three male physicians working in the Division of Endocrinology at The Mount Sinai Hospital. Since no other instances of hyperthyroidism developed among the hospital medical or dental attending staff, to the authors' knowledge, during the years of 1953-1973, this incidence appears to indicate an unusual occurrence. (Information regarding other possible instances of thyrotoxicosis was obtained by questioning all of the physicians in the Division of Endocrinology at The Mount Sinai Hospital, members of the Division of Endocrinology at the other major institutions in the city and, finally, inquiry of the physicians in the Department of Medicine at The Mount Sinai Hospital.)

Publisher Summary This chapter discusses the ways to individualize parent or family involvement in the education of children with disabilities. It addresses policies and practices for involving parents in individualized education program (IEP) conferences, as such meetings represent the most typical interactions between parents and school personnel. The chapter presents a rationale and implementation guidelines for an individualized approach to parent IEP conference involvement. It discusses—(1) the historical development of parent IEP involvement; (2) the legal bases for parent involvement; (3) the need, or rationale, for individualizing parent IEP involvement; (4) requirements for an individualized parent involvement approach; and (5) procedures and suggestions for individualizing parent IEP involvement before, during, and after the IEP conference. Parent participation in educational conferences, including IEP meetings, must be individualized and based on a number of family-system considerations. Further, if parents are to assume a meaningful role in their exceptional child's education, educators must demonstrate cooperative attitudes and behaviors along with providing appropriate parent training for various participation levels.

There is considerable interest in developing a means of assessing dietary intake of specific nutrients with minimal time and expense in epidemiologic studies. Using data from 1,682 individuals who were interviewed using an extensive food frequency dietary history, the authors examined the question of how many foods might be minimally required in order to estimate specific nutrient intakes for epidemiologic purposes. Nutrient indices were constructed for vitamins A and C, dietary fiber, fat, protein, and total calories based on 128 foods included in the interview. They found that a large fraction of the variability of nutrient intake in this population could be explained by a small number of foods. An abbreviated dietary history ascertaining the intake of as few as 15-20 food items may be all that is required in order to test the association between disease outcome and the intake of a single nutrient.

In der nachfolgenden Ubersicht sind die in den wichtigsten Landern erteilten Patente betr. Herstellung, Verarbeitung und Verwendung von Magnesium und Magnesiumlegierungen nach Gruppen geordnet zusammengestellt.

Magnesium und seine Legierungen lassen sich in gleicher Weise wie andere Metalle in der Warme auf einer hydraulischen Strang oder Stangenpresse nach dem bekannten Dickschen Presverfahren verformen. Das Verfahren besteht darin, das gegossene Rundblocke in einem elektrisch oder gasbeheizten Ofen auf die erforderliche Prestemperatur vorgewarmt werden ; diese liegt bei den hier zu behandelnden Magnesiumlegierungen zwischen 300–400° C. Der Block nimmt nach einer genugend lange bemessenen Zeit im Ofen die notwendige Temperatur an und wird dann in den Rezipienten oder Aufnehmer der Presse eingefuhrt. Wegen der verhaltnismasig niederen Verformungstemperaturen und der sonstigen Warmeverhaltnisse ist es beim Pressen von Magnesiumlegierungen erforderlich, den Aufnehmer zusatzlich zu erwarmen. Diese Vorwarmung ist so zu bemessen, das in der Innenwand des Aufnehmers die gleiche Temperatur herrscht, die der Block beim Verpressen besitzt ; liegt die Temperatur darunter, so wird bei der verhaltnismasig langen Preszeit, die die Magnesiumlegierungen zum Teil erfordern, und die je nach Profilform bis zu etwa 15 Minuten pro Pressung betragen kann, dem Block die Warme entzogen, so das ein Fliesen des Metalls schlieslich nicht mehr stattfindet, mit anderen Worten : der Block bleibt stecken und mus dann aus der Presse ausgestosen werden.

Titin-truncating variants (TTNtv) commonly cause dilated cardiomyopathy (DCM). TTNtv are also encountered in 1/41% of the general population, where they may be silent, perhaps reflecting allelic factors. To better understand TTNtv, we integrated TTN allelic series, cardiac imaging and genomic data in humans and studied rat models with disparate TTNtv. In patients with DCM, TTNtv throughout titin were significantly associated with DCM. Ribosomal profiling in rat showed the translational footprint of premature stop codons in Ttn, TTNtv-position-independent nonsense-mediated degradation of the mutant allele and a signature of perturbed cardiac metabolism. Heart physiology in rats with TTNtv was unremarkable at baseline but became impaired during cardiac stress. In healthy humans, machine-learning-based analysis of high-resolution cardiac imaging showed TTNtv to be associated with eccentric cardiac remodeling. These data show that TTNtv have molecular and physiological effects on the heart across species, with a continuum of expressivity in health and disease.