Cenozoic evolution of deep ocean temperature from clumped isotope thermometry.

Characterizing past climate states is crucial for understanding the future consequences of ongoing greenhouse gas emissions. Here, we revisit the benchmark time series for deep ocean temperature across the past 65 million years using clumped isotope thermometry. Our temperature estimates from the deep Atlantic Ocean are overall much warmer compared with oxygen isotope-based reconstructions, highlighting the likely influence of changes in deep ocean pH and/or seawater oxygen isotope composition on classical oxygen isotope records of the Cenozoic. In addition, our data reveal previously unrecognized large swings in deep ocean temperature during early Eocene acute greenhouse warmth. Our results call for a reassessment of the Cenozoic history of ocean temperatures to achieve a more accurate understanding of the nature of climatic responses to tectonic events and variable greenhouse forcing.

Control of jaw movements in two species of macropodines (Macropus eugenii and Macropus rufus).

The masticatory motor patterns of three tammar wallabies and two red kangaroos were determined by analyzing the pattern of electromyographic (EMG) activity of the jaw adductors and correlating it with lower jaw movements, as recorded by digital video and videoradiography. Transverse jaw movements were limited by the width of the upper incisal arcade. Molars engaged in food breakdown during two distinct occlusal phases characterized by abrupt changes in the direction of working-side hemimandible movement. Separate orthal (Phase I) and transverse (Phase II) trajectories were observed. The working-side lower jaw initially was drawn laterally by the balancing-side medial pterygoid and then orthally by overlapping activity in the balancing- and working-side temporalis and the balancing-side superficial masseter and medial pterygoid. Transverse movement occurred principally via the working-side medial pterygoid and superficial masseter. This pattern contrasted to that of placental herbivores, which are known to break down food when they move the working-side lower jaw transversely along a relatively longer linear path without changing direction during the power stroke. The placental trajectory results from overlapping activity in the working- and balancing-side adductor muscles, suggesting that macropods and placental herbivores have modified the primitive masticatory motor pattern in different ways.

Evaluation of criteria for chronic lung disease in surviving very low birth weight infants. Newborn Lung Project.

Criteria in common use for the diagnosis of chronic lung disease of prematurity or bronchopulmonary dysplasia in the neonatal period have not been sufficiently compared and validated against indicators of later respiratory complications. In this study of all 680 infants < or = 1500 gm birth weight admitted to six perinatal centers August 1, 1988, to July 31, 1990, 524 were alive and had no major congenital anomalies at 5 years old. Of 419 who had given permission to release their names and addresses, 272 were located and participated in a follow-up study. The following diagnostic criteria for bronchopulmonary dysplasia and chronic lung disease of prematurity were used during the initial hospitalization: (1) use of supplemental oxygen on day 30 of life, (2) a comprehensive bronchopulmonary dysplasia severity score applied at 25 to 35 days of life developed by a clinician panel to adjust for practice variation in ventilatory support and blood gases, (3) use of supplemental oxygen on day 30 of life with radiographic evidence consistent with bronchopulmonary dysplasia between days 25 and 35 of life, (4) radiographic evidence consistent with bronchopulmonary dysplasia alone, and (5) use of supplemental oxygen at 36 weeks' postconceptional age. These criteria were assessed against use of bronchodilators or steroids during the first 2 years of life, diagnosis of asthma, and hospitalizations for respiratory causes up to age 5. Although all criteria were significantly associated with all the outcomes, radiographic evidence was most predictive. These results indicate that, during a period when 21% of neonates were exposed to antenatal steroids, 24% received surfactant and 9% received postnatal corticosteroids, radiographic evidence was more predictive of long-term respiratory outcome than other commonly used criteria.

The effect of right or left placement of the positive response on Likert-type scales used by medical students for rating instruction.

PURPOSE: To determine whether students' ratings of instruction demonstrate a primary effect, to determine whether the primacy effect relates to the number of response options, and to assess whether the primacy effect relates to how favorably the instructional activity is rated. METHOD: Inf 1995-96 six different forms of a 13-item course-evaluation questionnaire (with Likert-type items) were used to evaluate two second-year courses, Respiratory and Hepatic, at the University of Wisconsin Medical School; the first was one of the most highly rated courses at Wisconsin, and the second was less highly rated. The forms differed by whether they contained five, six, or seven response options, and whether the "strongly agree" rating was on the left side or the right side of the page. The second-year class that participated in the study comprised 140 students. The six different forms of the course-evaluation questionnaires were randomly distributed to the students in equal numbers. Results were analyzed with a number of statistical methods. RESULTS: Completed questionnaires were obtained from 132 students (94%) in Respiratory and from 119 students (85%) in Hepatic. Overall, the forms with the positive rating on the left side had more positive ratings and less variance. For Respiratory, primacy affected the response variance. For Hepatic, primacy affected the response means. CONCLUSION: Faculty-evaluation systems are increasingly using students' ratings for making important decisions regarding salaries, teaching assignments, tenure, etc. The evidence that the primacy effect influences such ratings highlights the need to standardize as much as possible how such ratings are obtained.

[Cognitive deterioration in Parkinson's disease]. / Deterioro cognitivo en la enfermedad de Parkinson.

The purpose of this study is to contrast a sampling of 20 patients diagnosed as suffering from "Idiopathic Parkinson's Disease" (mean age, 54; schooling, 8.5 years; length of disease, 6.07 years) with a healthy control group, in order to detect possible correlation between intellectual impairment and depression in the individuals affected by Parkinsonism. An integrated battery of neuropsychological testing (PIEN-Test Barcelona. Peña, 1990) was used, in conjunction with "Beck's Depression Inventory". The results show significant differences in the following areas: expressive language, complex language comprehension, motor coordination, complex visuospatial factors, verbal memory and WAIS-type intelligence factors. Discriminant analysis was performed to select the most discriminating variables. The results were as follows, beginning with the most discriminating factor: motor coordination, complex comprehension, complex visuospatial factors, math skills and an overall slowing down. The patients with the highest depression levels were found to have the greatest impairment in mental control/attention and complex comprehension.

[Current results of the aortic valve changes]. / Resultados actuales del cambio valvular aórtico.

The prosthetic substitution of the aortic valve has experienced a great advance over the last years in relation with the surgical and hospital mortality. In the personal experience of one of the authors (F. López Soriano), the mortality rate was 0% in 40 patients in which an aortic valve change was performed, isolated or associated to other pathology. Between 1973 and 1978, 167 patients were operated at the "Instituto Nacional de Cardiología", with an early mortality of 11.3%; these results were superior to those previously published. The percentage of myocardic infarction following surgery was similar in both groups 8% less, than the 15% reported in other statistics. 25 patients of the total group needed second surgery due to prosthetic malfunction. A Starr Edward Model 2320 had been implanted on most patients, known for the high percentage of malfunction which is being discarted at present. Thromboembolic phenomena occurred in 9 patients (5.3%) from which five were located in the brain, none of them being fatal. The present results justify early surgery in moderately sinthomatic aortic valve disease, when comparing these results with the natural history of the disease and the evolution of said patients operated in later stages.

[DNA-intercalating compounds. Synthesis of several monomers and 1 dimer of phenanthridinium bearing aminoalkoylated chains]. / Composés d'intercalation de l'ADN. synthèse de quelques monomères et d'un dimère de phénanthridinium á chaînes aminoalcoylées

Several monomeric phenanthridinium salts quaternarized in the 5 position by different aminoalkyl chains are prepared from ammoniac or diamines and 3,8-biscarbethoxyamnio (3-bromo)-5 propyl 6-phenyl phenanthridinium bromide I. The reaction between one of the monomeric salts and I leads, after deprotection of the amino-groups to the dimer: (4,7-diaza decamethylene) bis 5,5' (3,8-diamino-6 phenyl phenanthridinium) tetrachloride. All these compounds show the fluorescence properties of the phenanthridinium ring and exhibit DNA affinity constant higher than ethidium bromide.

A maximal predictive classification of Klebsielleae and of the yeasts.

The concepts of the numerical method of maximal predictive classification are illustrated with classifications of 13 species of enterobacteria and of 434 species of yeast. The method seeks to classify into a specified number of classes (k) such that more correct statements can be made about the constituent members than with any other classification. The best choice of k relates to the separation of the classes as measured by the average number of correct statements made for an individual assigned to a class to which it does not belong. The maximal predictive classifications are compared with previous classifications of the two groups, which seem to be poor predictively (in terms of the characters considered in this study). The results suggest that taxonomists may be more concerned with maximizing class separation rather than with prediction, but many more groups of organisms would need similar study before this view could be held with confidence.