cssi/SciSciGPT-SciSciNet huggingface dataset:
Two-dimensional echocardiographic evaluation of mitral bioprosthetic function in infants and children.

Two-dimensional echocardiography (2DE) was perlormed on 13 bioprosthetic mitral valves in 11 pediatric patients, 1 week to 46 months following implantation. Cardiac catheterization confirmed the echocardiographic findings of seven valves. The 11 normally functioning bioprosthetic mitral valves by 2DE had leaflet thickness not exceeding 2.0 mm, treely moving leaflets, and normal sewing ring motion. The left atrium (LA) was enlarged only in the presence of mitral valve obstruction, atrial fibrillation, or left ventricular (LV) dysfunction. One bovine valve was stenotic due to fibrous tissue beneath normal valve leaflets; 2DE demonstrated limited leaflet motion, tissue beneath a thin valve leaflet, increased rocking motion of the sewing ring, and LA enlargement. In another patient, a bovine valve produced subaortic LV obstruction due to growth of fibrous tissue outside the stent; 2DE showed that the valve leaflets were thin and moved normally without excessive rocking of the valve ring, and identified the abnormal fibrous tissue in the LV outflow tract.
Translational cancer vaccine: from mouse to human to cat

Abstract A canthomatous ameloblastoma is a locally invasive tumor arising in the gingiva that can progress rapidly, invade and destroy bone. If the lesion involves the upper jaw, surgical excision may not be possible and while local control is imperative, other therapies have not been fully evaluated. The primary authors personal cat, Gabriella, developed this tumor, with gingival masses around teeth in the upper jaw and evidence of widespread bony destruction of the hard palate. Because of his involvement with Immunophotonics Inc. as an advisor, the author was aware of an in situ autologous cancer vaccine (inCVAX) that is currently under development by the company. One session was performed in a veterinary clinic in Arkansas, and two follow-up sessions at the small animal hospital at the UC Davis veterinary school. No other therapy was provided. As of this writing, 3+ years after first treatment and 3 years, 4 months after presentation, Gabriella is well, with no evidence of disease.
The Inuence of Neutron Capture Rates On The Rare Earth Region Of The r-Process Abundance Pattern

We study the sensitivity of the $r$-process abundance pattern to neutron capture rates along the rare earth region ($A\ensuremath{\sim}150$ to $A\ensuremath{\sim}180$). We introduce the concepts of large nuclear flow and flow saturation, which determine the neutron capture rates that are influential in setting the rare earth abundances. We illustrate the value of the two concepts by considering high entropy conditions favorable for rare earth peak production and identifying important neutron capture rates among the rare earth isotopes. We also show how these rates influence nuclear flow and specific sections of the abundance pattern.
A direct demonstration of cortical LTP in humans: a combined TMS/EEG study.

Abstract Repetitive transcranial magnetic stimulation (rTMS) is increasingly being used to promote cortical reorganization, under the assumption that it can induce long-term potentiation (LTP) of neural responses. This assumption is supported by several lines of indirect evidence. For example, rTMS of motor cortex can induce a potentiation of muscle motor evoked potentials that outlasts the stimulation by several minutes. In animal models, a direct demonstration of LTP is typically obtained by high-frequency electrical stimulation coupled with local field recordings of population responses. In this study, we exploited a new approach based on combined rTMS/high-density electroencephalography (hd-EEG) to obtain direct, noninvasive evidence for LTP in humans. Cortical responses to single TMS pulses were measured with hd-EEG before and after applying rTMS to motor cortex (5 Hz, 1500 pulses). The results demonstrate that, after rTMS, EEG responses at latencies of 15–55 ms were significantly potentiated. A topographic analysis revealed that this potentiation was significant at EEG electrodes located bilaterally over premotor cortex. Thus, these findings provide a direct demonstration in humans of LTP induced by rTMS.
Human Mitochondrial C1-Tetrahydrofolate Synthase GENE STRUCTURE, TISSUE DISTRIBUTION OF THE mRNA, AND IMMUNOLOCALIZATION IN CHINESE HAMSTER OVARY CELLS

C1-tetrahydrofolate (THF) synthase is a trifunctional enzyme found in eukaryotes that contains the activities 10-formyl-THF synthetase, 5,10-methenyl-THF cyclohydrolase, and 5,10-methylene-THF dehydrogenase. The cytoplasmic isozyme of C1-THF synthase is well characterized in a number of mammals, including humans; but a mitochondrial isozyme has been previously identified only in the yeast Saccharomyces. Here, we report the identification and characterization of the human gene encoding a functional mitochondrial C1-THF synthase. The gene spans 236 kilobase pairs on chromosome 6 and consists of 28 exons plus one alternative exon. The gene encodes a protein of 978 amino acids, including an N-terminal mitochondrial targeting sequence. The mitochondrial isozyme is 61% identical to the human cytoplasmic isozyme. Expression of the gene was detected in most human tissues, but transcripts were highest in placenta, thymus, and brain. Two mRNAs were detected, a 3.6-kb transcript and a 1.1-kb transcript, and both transcripts were observed in varying ratios in each tissue. The shorter transcript results from an alternative splicing event, where exon 7 is spliced to exon 8a instead of exon 8. Exon 8a is derived from an exonized Alu sequence, sharing no homology with exon 8 of the long transcript, and encodes just 15 amino acids followed by a stop codon and a polyadenylation signal. This short transcript potentially encodes a bifunctional enzyme lacking 10-formyl-THF synthetase activity. Both transcripts initiate at the same 5′-site, 107 nucleotides up-stream of the ATG start codon. The full-length (2934 bp) cDNA fused to a C-terminal V5 epitope tag was expressed in Chinese hamster ovary cells. Immunoblots of subfractionated cells revealed a 107-kDa protein only in the mitochondrial fractions of these cells, confirming the mitochondrial localization of the protein. Yeast cells expressing the full-length human cDNA exhibited elevated 10-formyl-THF synthetase activity, confirming its identification as the human mitochondrial C1-THF synthase.
Human urinary N-acetyl-β-hexosaminidases

Analysis of urinary N-acetyl-β-hexosaminidases (β-2-acetamido-2-deoxy-d-glucoside acetamidodeoxyglucohydrolase, EC 3.2.1.30) by DEAE-cellulose chromatography revealed the presence of both the A and B isozymes and a new minor component designated N-acetyl-β-hexosaminidase M. This form, found only in male urine, was similar in its properties to the A form. The N-acetyl-β-hexosaminidase patterns were qualitatively similar between normal individuals and Tay-Sachs heterozygotes. N-Acetyl-β-hexosaminidase A was absent from urine of a Tay-Sachs patient.
Trying to do group theory with undergraduates and computers

Abstract This paper discusses the author's efforts to use computers and software as a catalyst for engaging undergraduates in the process of doing mathematics in the context of finite group theory. Examples of questions that have been used to motivate undergraduate research and a classroom case study are presented.
Who mentors? Contextual prosocial motivation and willingness to be a mentor

This study provides insights for theory and practice into employee willingness to mentor. This is especially important in passing knowledge from one generation of employees to another at a time when ageing populations are seen in many parts of the world. The study examines the relationship of contextual prosocial motivation with willingness to be a mentor while simultaneously considering various individual level influences on contextual prosocial motivation. Hypotheses were evaluated through a structural equation model. Results showed a positive relationship between contextual prosocial motivation and willingness to be a mentor. Additionally, organization-based self-esteem was positively related to contextual prosocial motivation, while proximity to retirement was negatively related to contextual prosocial motivation. Implications of the findings for human resource development are discussed with suggestions offered to strengthen contextual prosocial motivation of employees.
X-Ray Emission Spectra of Sulphides and Sulphates

A target for exciting x-ray emission spectra of chemical compounds is described. The wave-lengths of the $K\ensuremath{\beta}$ lines of alkaline earth sulphates and of some semiconducting sulphides are given. Using these results and the wave-lengths of the $K$ absorption edges, the energy gap between the occupied and unoccupied zones in these crystals is obtained. The results for the sulphates are compared with the results previously obtained for the corresponding sulphides. In order to account for the changes in emission wave-lengths from compound to compound, a nonuniform displacement of energy levels is needed in addition to the Madelung energy. A recent article by Slater and Shockley suggests one way in which this may be accomplished.
Evaluation of efficacy of an ultrasonic scalpel for pulmonary vascular ligation in an animal model

Objective Dissection to accommodate bulky stapling devices may cause injury to pulmonary arteries in thoracoscopic lobectomies. The Harmonic Ace (Ethicon Endo-Surgery, Inc; Cincinnati, Ohio), a small ultrasonic scalpel used in systemic vessels, was tested on pulmonary vessels in pigs. Methods Nine pigs were assigned 1- or 6-week survival. Lobectomies were performed using the device to divide and ligate pulmonary vessels. Vessel diameter was measured, and ligation outcome was recorded. Necropsies were then performed. Results Permanent ligation occurred in 76% of arteries and 92% of veins. At the highest power setting, the instrument showed no failure in arteries 5 mm or less and veins 7 mm or less. Necropsies revealed no evidence of postoperative bleeding. Histopathologic analysis revealed acute coagulation necrosis at 1 week. By 6 weeks, the vessel stumps displayed features consistent with normal wound healing. Conclusions This device reliably divides pulmonary vessels 4 mm and smaller, typically encountered in pig lobectomies. Higher power settings and operator experience may increase effectiveness. Further testing is necessary to delineate the device's limitations before potential use in human pulmonary vasculature.
Interactive spreadsheet models reinforce accounting principles

Abstract This note presents an interactive spreadsheet model requiring students to create formulas that complete an incomplete, preexisting spreadsheet model and thereby demonstrate their understanding of the accounting principle being applied. The model's verification feature uses keyboard macro commands that compare the student's formulas to correct formulas stored on the spreadsheet. If any formula is incorrect, the error is highlighted and an online help screen is displayed to assist the student in preparing a correct solution. Interactive models provide students with immediate knowledge of results and improve the efficiency of class administration.
How does Adenosine Alter Sperm Motility

Adenosine is a candidate modulator of motility of spermatozoa as they progress through the female reproductive tract. Past work demonstrated that the adenosine analog 2-chloro-deoxyadenosine (Cl-dAdo) accelerates the flagellar beat rate of mouse sperm by a cAMP/PKA-mediated pathway with a pharmacological profile suggestive of a Slc29a (ENT) equilibrative nucleoside transporter. Using qRT-PCR we find in adult mouse testis 160- and 32-fold greater expression of Slc29a1 than of the other surface-membrane ENT transporters Slc29a4 and Slc29a2. However, Slc29a1 protein was not found on mature sperm using immunocytochemistry. Moreover, wildtype and Slc29a1-null mice accelerate at similar rates (1.5-2.0 Hz min−1) in response to Cl-dAdo indicating that Slc29a1 is not required for Cl-dAdo action. Consistent with this observation, the accelerating action of Cl-dAdo resists the Slc29a-selective inhibitor nitrobenzylthioinosine (NBTI; 10 μM). The accelerating action of Cl-dAdo additionally resists replacement of external Na+ with NMDG+ indicating that Slc28a concentrative nucleoside transporters (CNTs) also are not required. Interestingly, the Adenosine A3 receptor-selective agonist Cl-IB-MECA (25 μM) is nearly as effective as Cl-dAdo in accelerating sperm beat frequency, suggesting a possible role for cell surface A3 receptors in Cl-dAdo-mediated increases in sperm motility. Two A3 isoforms are expressed in the mouse Adora3i1 and Adora3i2; Adora3i2 expression is testis specific. Adora3i1 null sperm increase beat frequency in response to both Cl-IB-MECA (25 μM) and Cl-dAdo (25 μM), so this isoform is not needed for sperm response to adenosine. Sperm response to Cl-dAdo and Cl-IB-MECA is diminished after pertussis toxin treatment of cells suggesting the receptor is Gαi/o coupled. We are currently testing functionality of the testis-specific novel Adora3i2 isoform in a heterologous system. Support from U54-HD12629 of the SCCPRR program of NICHD. L.A.B. supported in part by 5-T32-HD007453.
Ethyl alcohol iphibits habituation of the nictitating membrane reflex response in the intact frog

Habituation of the nictitating membrane reflex response in the intact frog was examined under conditions of various alcohol doses, administered by whole-body immersion into dilute alcohol solutions. Alcohol both markedly reduced the initial response amplitudes and severely disrupted the habituation process in a dose-dependent manner. A theoretical discussion is presented in which the effects of alcohol on habituation in other systems, and the interaction of alcohol with known neural processes, are examined. The results and conclusions are consistent with other reports of presynaptic inhibition modulating habituation at an invertebrate central synapse.
Identification, structure, and differential expression of members of a BURP domain containing protein family in soybean

Expressed sequence tags (ESTs) exhibiting homology to a BURP domain containing gene family were identified from the Glycine max (L.) Merr. EST database. These ESTs were assembled into 16 contigs of...
Improving Retention and Academic Achievement for First-Time Students at a Two-Year College

Faculty at a two-year community/technical college undertook a project in the spring 2010 semester to incorporate more intensive and intrusive academic advising into the Freshman Seminar (COL 105) course. A study was undertaken in which 14 sections of COL 105 were divided into an experimental group (taught by specially-trained instructors who served as the students’ academic advisors during their first semester) and a control group (taught by regularly trained instructors who were not advising their students). Results showed that the students in the experimental group earned higher overall GPAs and were retained (reenrolled the following semester) at a higher rate than students in the control group, a phenomenon that remained true for the following year.
THE PAST TENSES IN FRENCH

THE distinction between the past definite, imperfect, and past indefinite tenses is, in a measure, indicated by their names. When we wish to speak of an act that was completely finished in time completely past of which the present forms no part, we use the past definite. The standpoint of the speaker is also to be taken into consideration. In the case of the tense under discussion, the speaker stands in the present and views an act as complete in time long since elapsed.l In the imperfect, on the contrary, the idea of completion does not enter into our consideration. We are thinking more of the situation, the setting, the frame, the picture, if you please, in which acts take place. In the case of the past definite, a definite beginning and a definite end are evident; in the imperfect neither beginning nor end is marked off. We, therefore, use the imperfect to express the customary, often repeated, physical and mental characteristics, subordinate details, as well as anything added by way of interpolation and not absolutely essential to the main course of the narrative.2
Time-dependent superconducting behavior of oxygen-deficient YBa2Cu3Ox: Possible annealing of oxygen vacancies at 300 K.

Oxygen stoichiometries in single crystals of ${\mathrm{YBa}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{\mathit{x}}$ are controlled by quenching from an ${\mathrm{O}}_{2}$-${\mathrm{N}}_{2}$ atmosphere at 520 \ifmmode^\circ\else\textdegree\fi{}C to liquid nitrogen. After quenching, the superconducting behavior and lattice parameters are found to be time dependent. ${\mathit{T}}_{\mathit{c}}$ increases as much as 15 K in a period of several days. Apparently, annealing, with increasing oxygen vacancy order, occurs at room temperature.
Nitro musks in human milk

Abstract 391 milk samples (48 in the year 1991 and 343 in 1992) of nursing mothers living in Southern Bavaria, Germany, were analyzed by GC/ECD for the synthetic nitro musks musk xylene (CAS No. 81-15-2), musk ketone (CAS No. 81-14-1), and musk ambrette (CAS No. 83-66-9). Musk ambrette and musk ketone were detected in similar amounts ranging from
The role of systems engineering in security systems design

To design today's complex networks and computerbased physical protection systems require the application of sound Systems Engineering principles and discipline. This paper provides an introduction to using several Systems Engineering tools to design advanced security systems. Examples are given for specific design tasks, and concepts from the US Department of Defense Architecture Framework are introduced.
X‐LRT: a likelihood approach to estimate genetic risks and test association with X‐linked markers using a case‐parents design

Recently, there has been interest in family-based tests of association to identify X-chromosome genes. However, none of the approaches allow for estimation of genetic risks. We propose a likelihood approach to estimate disease-related marker relative risks and test genotype association using a case-parents design. The test uses nuclear families with a single affected proband and allows additional siblings and missing parental genotypes. Extension to a haplotype test is based on assumptions of random mating and multiplicative penetrance. We investigate power and type I error rate of the likelihood-based test, using simulated data and apply our method to marker data from the monoamine oxidase A&B genes in families with Parkinson disease. We show how efficiency with missing parental information can be improved with additional sibling genotype information. Our likelihood approach offers great flexibility for testing different penetrance relationships within and between sexes. In addition, estimation of disease-related marker relative risks provides a measure of the magnitude of X-linked genetic effects on complex disorders.
Anthropological issues in renal care

This article provides a brief overview of the critical role that culture can play in renal care, drawing on examples from the social scientific literature to discuss cultural beliefs in three key domains at issue in renal care: beliefs about the kidney itself, about kidney disease, and about kidney treatments. Examining cultural variation within these three key domains across settings ranging from Mexico, USA, China, Egypt, Japan, Turkey, and others provides a means for thinking more deeply and strategically about the role of culture in caring for nephrology patients. The article concludes by offering specific practice strategies designed to strengthen the understanding and communication between clinicians and patients around cultural issues in renal care.
Source contributions to the regional distribution of secondary particulate matter in California

Abstract Source contributions to PM2.5 nitrate, sulfate and ammonium ion concentrations in California's San Joaquin Valley (SJV) (4–6 January 1996) and South Coast Air Basin (SoCAB) surrounding Los Angeles (23–25 September 1996) were predicted using a three-dimensional source-oriented Eulerian air quality model. The air quality model tracks the formation of PM2.5 nitrate, sulfate and ammonium ion from primary particles and precursor gases emitted from different sources though a mathematical simulation of emission, chemical reaction, gas-to-particle conversion, transport and deposition. The observed PM2.5 nitrate, sulfate and ammonium ion concentrations, and the mass distribution of nitrate, sulfate and ammonium ion as a function of particle size have been successfully reproduced by the model simulation. Approximately 45–57% of the PM2.5 nitrate and 34–40% of the PM2.5 ammonium ion in the SJV is formed from precursor gaseous species released from sources upwind of the valley. In the SoCAB, approximately 83% of the PM2.5 nitrate and 82% of the PM2.5 ammonium ion is formed from precursor gaseous species released from sources within the air basin. In the SJV, transportation related sources contribute approximately 24–30% of the PM2.5 nitrate (diesel engines ∼13.5–17.0%, catalyst equipped gasoline engines ∼10.2–12.8% and non-catalyst equipped gasoline engines ∼0.3–0.4%). In the SoCAB, transportation related sources directly contribute to approximately 67% of the PM2.5 nitrate (diesel engines 34.6%, non-catalyst equipped gasoline engine 4.7% and catalyst equipped gasoline engine 28.1%). PM2.5 ammonium ion concentrations in the SJV were dominated by area (including animal) NH3 sources (16.7–25.3%), soil (7.2–10.9%), fertilizer NH3 sources (11.4–17.3%) and point NH3 sources (14.3–21.7%). In the SoCAB, ammonium ion is mainly associated with animal sources (28.2%) and catalyst equipped gasoline engines (16.2%). In both regions, the majority of the relatively low PM2.5 sulfate (
The Effect of Dietary Modifications on Aflatoxicosis in the Broiler Chicken

Abstract INTRODUCTION A FLATOXICOSIS in broilers appears to be a disease characterized by poor growth rates and inefficient feed conversions rather than a catastrophic disease characterized by high mortality (Gardiner and Oldroyd, 1965; and Carnaghan et al., 1966). At the present time there does not appear to be any way of preventing or ameliorating the disease other than avoiding conditions conducive to the formation of aflatoxin in feedstuffs and avoiding feed with preformed aflatoxin. Because of the nature of the feed distribution system in the poultry industry, this avoidance is difficult. A more economical solution would be the development of a dietary additive or modification that would make the birds more resistant to aflatoxin. There are several reports in the literature which indicate that dietary alterations have an influence on the severity of aflatoxicosis. Newberne et al. (1968) found that a diet low in lipotropes made the livers of rats more…
Case study: A comparison of error sources in high-speed milling

This paper describes a case study devised to quantify the relative contributions of geometric, thermal, contouring, and cutting force errors to machined part dimensional errors. Measurements were performed to independently evaluate the: (1) quasi-static geometric errors using the laser ball bar; (2) variations in geometric errors due to thermal effects; (3) spindle thermal growth errors using a capacitance gage nest; (4) two-dimensional contouring errors using a grid plate encoder; and (5) surface location error due to (stable) forced vibrations during cutting. The effects of the first three error components were related to part dimensions using a homogeneous transformation matrix approach integrated into a Monte Carlo simulation. A comparison of the individual influences of these error sources showed that the cutting force error was dominant for the high-speed machining center/tool-holder combination selected for this study.
Reactions of tris(oxalato)cobaltate(III) with two-electron reductants.

The tris(oxalato)cobaltate(III) complex [Co(C2O4)3]3−, EoCoIII/II = +0.57 V) is readily reduced by the 2e− reagents, Sn(II) and Ge(II), in contrast to (NH3)5CoCl2+ and (NH3)5CoBr2+, which are unreactive toward these donors. Rates for the oxalato oxidant are only 10−3–10−2 as great as those for vitamin B12a (aquacob(III)alamin, Eo +0.35 V at pH 1), in accord with the suggestion that reductions of corrin-bound cobalt(III) by Sn(II) and Ge(II) occur predominantly through an additional path involving Co(I). Reductions of the oxalato complex by 2e− donors are taken to proceed by initial formation of odd-electron intermediates (e.g., SnIII and GeIII) which react rapidly with CoIII. Such a two-step sequence is in keeping with the observed behavior of the rare reductant, TiII, which is found to be oxidized by [Co(C2O4)3]3− more slowly than (independently prepared) Ti(III) under comparable conditions.
Congenital cricopharyngeal achalasia in a 4.5-year-old managed by cervical myotomy: a case report.

Abstract Introduction Congenital cricopharyngeal achalasia (CCA) is a rare disorder in children characterized by inappropriate contraction of the cricopharyngeus muscle, resulting in the inability to relax the upper esophageal sphincter during deglutition. We report the diagnostic process and management of a relatively older patient who underwent cricopharyngeal myotomy at the age of 4.5 years. Methods A retrospective review of the case and clinical follow-up was performed. Results This young patient had a long history of dysphagia, choking, nasal reflux and recurrent pneumonia and croup since birth and was diagnosed with CCA at 22 months of age. She underwent balloon dilation of the cricopharyngeus muscle shortly thereafter with only transient relief of her symptoms of feeding difficulty (choking and aspiration). The parents were reluctant for her to undergo further interventions until 2 years later when they consented to cricopharyngeal myotomy. She underwent transcervical myotomy at age 4.5 years and had complete relief of her symptoms. She had no post-operative complications and has done well for nearly 12 months following myotomy. Discussion Our patient is one of the oldest children reported to have undergone myotomy, recovered quickly, and had no difficulty swallowing at any time following surgery. We suggest transcervical cricopharyngeal myotomy as the preferred treatment due to its lasting effects and repeated success in relieving dysphagia in young patients with CCA.
Selection for High Gamete Encounter Rates Explains the Success of Male and Female Mating Types

Abstract Sexual reproduction occurs in many small eukaryotes by fusion of similar gametes (isogamy). In the absence of distinguishable sperm and eggs, male and female mating types are missing. However, species with distinct males and females have so prospered that almost all familiar plants and animals have these mating types. Why has sexual reproduction involving sperm and eggs been so successful? An answer is obtained by considering physical limitations on encounter rates between gametes. A biophysical model based on well-established relationships produces fitness landscapes for the evolution of gamete size and energy allocation between motility and pheromone production. These landscapes demonstrate that selection for high gamete encounter rates favors large, pheromone-producing eggs and small, motile sperm. Thus, broadcast-spawning populations with males and females can reproduce at lower population densities and survive under conditions where populations lacking males and females go extinct. It appears that physical constraints on gamete encounter rates are sufficient to explain the first two steps in the isogamy→anisogamy→oogamy→internal fertilization evolutionary sequence observed in several lineages of the eukaryotes. Unlike previous models, assumptions concerning zygote fitness or decreasing speed of swimming with increasing gamete size are not required.
The Energy Loss of Protons in Metallic Foils and Mica

The rate of loss of energy of 500- to 1300-kev protons in various metals and mica has been determined. Foils of Be, Al, Cu, and Au were prepared by evaporation techniques, and the density of the foil was determined by weighing the amount of metal deposited on a known area. The energy loss rate $\frac{\ensuremath{\Delta}E}{\ensuremath{\Delta}x}$ was measured with a standard deviation of 3 percent. The energy loss curve was found to join smoothly to the previously measured curve for lower energy protons ($50 \mathrm{kev}E350 \mathrm{kev}$), and to approach the theoretical curves of Bethe and Bloch at the high energy end.
Performance of Large Steam Turbine Journal Bearings

Behavior of 16 and 20-inch diameter bearings of elliptical and pad types are examined for speeds ranging up to 5000 rpm and loads up to 1200 psi. The higher power loss, greater oil film thickness, and oil feed requirements are evaluated for the turbulent oil film conditions existing at the upper test speeds. The laminar-turbulent transition speed is found to be strongly related to bearing loading. Presented at the 25th ASLE Annual Meeting in Chicago, May 4–8, 1970
Methods of assessing graduate programs in speech communication

All graduate programs are subject to periodic assessment. The aim of this essay is to assist speech communication departments prepare for self‐study and review. Because such reviews are important to a department's welfare, they must be conducted intelligently. Standards and methods for evaluation are discussed as are characteristics of program quality. The emphasis is on improvement of speech communication graduate programs.
Concepts of Disease in Mexican‐American Culture1

communities studied. Mecca is a small city of approximately 15,000 inhabitants located on the delta of the Rio Grande. Three-fifths of the total population is comprised of persons of Mexican descent, a great number of whom are native-born American citizens. The overwhelming majority of the Spanish-speaking people of Mecca trace their roots to isolated, rural hamlets which lie on either side of the Rio Grande-south to the Rio Panuco in Mexico and north to the Nueces River of Texas. The life histories of the present older generation MexicanAmericans portray the lives of their parents as spent from birth to death in isolated, familial hamlets, which were seldom visited by strangers. In the era which followed the overthrow of Porfirio Diaz in the Republic of Mexico, the usually oppressive living conditions in the arid, northeastern section of the Republic were made worse by the furies of revolution and counter-revolution, of banditry and punitive government expeditions which swept across the land. This is the area from which the Mexican-American population of Mecca came. The poverty and the general insecurity of the times caused many thousands of emigrants to seek improved conditions on the United States side of the boundary. At the time of the surging unrest in the Republic to the south, all the previously undeveloped semi-desert delta lands, from Brownsville to Mission, Texas, were changing hands from the heirs of Spanish and Mexican recipients of 18th century grants (porciones) from the Spanish Crown to AngloAmerican speculators. From 1910 until 1930 the speculating land companies gained control of all irrigable land along the lower Rio Grande in Texas. By means of intensive systems of irrigation and emergency floodways the semi-desert region was transformed into a vegetable and citrus producing region of primary importance. After their development the tracts were resold
Grazing behavior of free-ranging beef cows to initial and prolonged exposure to fluctuating thermal environments

Effects of initial and prolonged exposure to cold ambient temperatures on the behaviors of free-ranging beef cows were examined over a fall and winter season. Mean daily temperature (MDT) and short-term thermal stress (STTS) were used to express thermal stressors. Short-term thermal stress was defined as the deviation of the current day's mean temperature from a running mean temperature of previous days (an acclimation period). Twenty different acclimation periods (calculated using temperatures from the previous 1–20 days) were used to express 20 different acclimation lengths for determining STTS. Daily grazing time and forage intake were estimated for 15, 6-year-old gestating cows during January and February (winter trial), and for 12 of these cows during October and November (fall trial). In the winter, daily grazing time increased with increased ambient temperature and decreased with increased thermal stress (P<0.10). Observed fluctuations in winter daily grazing time in relation to thermal stress were less than 84 min day−1. Daily grazing time was lower in the fall than winter. Cattle acclimated more quickly to STTS in the winter than in the fall. However, forage intake was consistent during both seasons and unresponsive to thermal stress. The thermal environment in these northern latitudes appeared to be only a minor influence upon grazing behaviors. It is likely that forage quality and availability, and accessibility of sites with moderate microclimates are more important environmental features effecting daily intake and total grazing time.
Competitive adsorption, phase segregation, and molecular motion at a solid-liquid interface studied by scanning tunneling microscopy

Binary mixtures of 4‘-octyl-4-biphenylcarbonitrile (8CB) and n-tetracontane (C40H82) deposited as crystalline monolayers from a bulk fluid droplet on a graphite substrate were found to undergo nanometer-scale phase segregation into pure 8CB and pure alkane domains. Film morphology, molecular ordering, and domain motion were studied using scanning tunneling microscopy. Alkane adsorption was favored in the early stages of film growth, which was followed by a period of gradual annealing in which 8CB displaced alkane molecules from the surface. The structure and composition of the monolayer show that in films deposited from a bulk fluid with a 600:1 molar ratio of 8CB/n-tetracontane 8CB adsorption is thermodynamically favored. However, n-tetracontane had a significantly larger nucleation rate, leading to high alkane surface coverage shortly after film formation. Quantitative rate measurements of alkane domain replacement by 8CB have been made and correlated with the microscopic structure of the 8CB−alkane int...
Effects of molecular weight on selected physical properties of polyaromatic ether-ketones

Polyaromatic ether-ketones with various inherent viscosities were prepared and their thermal properties and stress–strain relationships were studied. It was found that the polymer should have an inherent viscosity greater than 0.8 in order to give flexible films, but there was no difference in thermal and stress–strain properties among polymers with viscosities greater than 0.8. Values of 110 MPa and 13% are considered to be the standard values of tensile strength and elongation, respectively, for these polyaromatic ether-ketones. The crosslinking effects on these properties were also studied, using polymers containing 1 and 5 mol % of crosslinkable biphenylene units, but no significant changes in the properties due to crosslinking were observed.
Development and characterization of a polyclonal antiserum-based radioimmunoassay for dog osteocalcin

Determination of the serum concentration of the protein osteocalcin (OC) is useful for the noninvasive evaluation of bone metabolism. Because the dog is an excellent experimental model for the study of bone, we produced and characterized a polyclonal antiserum specific for dog OC and used it to develop a radioimmunoassay (RIA) for the measurement of the concentration of this protein in dog serum. The antiserum expresses higher affinity for Ca2+-bound than for Ca2+-free OC (B50 at 10−5 versus 2 × 10−4 dilution). Also, in the presence of Ca2+ affinity is higher for the carboxylated than for the decarboxylated form of the protein, and under Ca2+-free conditions the affinity is equal for the two forms. The study of peptide fragments of OC demonstrates competitive binding of the peptide comprising amino acids 20–44 but not of other fragments; this suggests that the antigenic epitope of dog OC is located in the midmolecular region of the protein. The RIA displays excellent sensitivity for the measurement of OC in blood (detection limit 0.31 ng/ml), with intraassay and interassay variations of 4.6 and 6.8%, respectively. Analysis of gel chromatography fractions of normal dog serum shows that greater than 90% of the antigenic material coelutes with purified radiolabeled dog OC. Test of parallelism reveals lack of interference of serum constituents with the binding assay. The antiserum displays limited species specificity since it cross-reacts with human OC, but not with the protein from rodents. Consistent with previous observations in other in vivo models, the serum concentration of OC in experimental dogs is decreased significantly 7–10 days after thyroparathyroidectomy and it is unchanged 1 month following ovariohysterectomy.
Evaluation of New Medium for Identification of Dermatophytes and Primary Dimorphic Pathogens

Only 25 of 77 dermatophytic isolates caused dermatophyte identification medium (DIM) to turn purple after incubation at the recommended temperature (37°C); the accuracy of the results was improved at 30°C (71 of 77 isolates yielded positive results). Many dimorphic pathogenic fungi also tested positive at both incubation temperatures. Thus, DIM has limited usefulness for presumptive identification of dermatophytes.
Chemically Specific Dynamic Bond Percolation Model for Ion Transport in Polymer Electrolytes

We introduce a coarse-grained approach for characterizing the long-timescale dynamics of ion diffusion in general polymer electrolytes using input from short molecular dynamics trajectories. The approach includes aspects of the dynamic bond percolation model [J. Chem. Phys. 1983, 79, 3133−3142] by treating ion diffusion in terms of hopping transitions on a fluctuating lattice. We extend this well-known approach by using short (i.e., 10 ns) molecular dynamics (MD) trajectories to predict the distribution of ion solvation sites that comprise the lattice and to predict the rate of hopping among the lattice sites. This yields a chemically specific dynamic bond percolation (CS-DBP) model that enables the description of long-timescale ion diffusion in polymer electrolytes at a computational cost that makes feasible the screening of candidate materials. We employ the new model to characterize lithium-ion diffusion properties in six polyethers that differ by oxygen content and backbone stiffness: poly(trimethylen...
Crystallography without crystals. I. The common-line method for assembling a three-dimensional diffraction volume from single-particle scattering.

It is demonstrated that a common-line method can assemble a three-dimensional oversampled diffracted intensity distribution suitable for high-resolution structure solution from a set of measured two-dimensional diffraction patterns, as proposed in experiments with an X-ray free-electron laser (XFEL) [Neutze et al. (2000). Nature (London), 406, 752–757]. Even for a flat Ewald sphere, it is shown how the ambiguities due to Friedel's law may be overcome. The method breaks down for photon counts below about 10 per detector pixel, almost three orders of magnitude higher than expected for scattering by a 500 kDa protein with an XFEL beam focused to a 0.1 µm diameter spot. Even if 103 orientationally similar diffraction patterns could be identified and added to reach the requisite photon count per pixel, the need for about 106 orientational classes for high-resolution structure determination suggests that about 109 diffraction patterns must be recorded. Assuming pulse and readout rates of ∼100 Hz, such measurements would require ∼107 s, i.e. several months of continuous beam time.
A Generalization of Lorenz’s Model for the Predictability of Flows with Many Scales of Motion

In a seminal paper, E. N. Lorenz proposed that flows with many scales of motion in which smaller-scale error spreads to larger scales and in which the error-doubling time decreases with decreasing scale have a finite range of predictability. Although the Lorenz theory of limited predictability is widely understood and accepted, the model upon which the theory is based is less so. The primary objection to the model is that it is based on the two-dimensional vorticity equation (2DV) while simultaneously emphasizing results using a basic turbulent flow with a “5/3” energy spectrum in the atmospheric synoptic scale instead of those using a more theoretically and observationally consistent “3” spectrum. The present work generalizes the Lorenz model so that it may apply to the surface quasigeostrophic equations (SQGs), which are mathematically very similar to 2DV but are known to have a 5/3 kinetic energy spectrum downscale from a large-scale forcing. This generalized Lorenz model is applied here to both 2DV (with a 3 spectrum) and SQG (with a 5/3 spectrum), producing examples of flows with unlimited and limited predictability, respectively. Comparative analysis of the two models allows for the identification of the distinctive attributes of a many-scaled flow with limited predictability.
Outcomes Associated With Enteral Tube Feedings in a Medical Intensive Care Unit

• BACKGROUND Underfeeding of patients reliant on enteral tube feedings most likely is due primarily to interruptions in the infusions. Strategies to improve energy intake require an understanding of such interruptions and associated outcomes. • OBJECTIVES To compare daily energy intake with goal energy intake; to ascertain frequency, duration, and reasons for interruptions in feedings; and to determine occurrences of feeding intolerance. • METHODS A prospective, descriptive study of a convenience sample of patients admitted during a 3-month period to a medical intensive care unit. Patients were included who were expected to receive continuous enteral tube feedings for at least 48 hours. Patients were studied until discontinuation of feedings, discharge from the unit, or death. • RESULTS Thirty-nine patients were studied for 276 feeding days. Patients received a mean of 64% of goal energy intake. Mean length of interruptions in feeding was 5.23 hours per patient per day. Interruptions for performance of tests and procedures accounted for 35.7% of the total cessation in feeding time. Next most time-consuming interruptions occurred with changes in body position (15%), unstable clinical conditions (13.5%), high gastric residual volume (11.5%), and nausea and vomiting (9.2%). Patients had diarrhea 105 (38%) of 276 feeding days. Gastric residual volumes exceeded 150 mL on 28 measurements in 11 patients. Five patients experienced episodes of nausea and vomiting. Four patients experienced an episode of feeding aspiration. • CONCLUSIONS Precautionary interruptions in enteral feedings to decrease presumed risk of aspiration occurred frequently and resulted in underfeeding. Episodes of vomiting and of aspiration were uncommon. (American Journal of Critical Care. 2004;13:221-227)
Estrogen and Tamoxifen Protect against Mn-Induced Toxicity in Rat Cortical Primary Cultures of Neurons and Astrocytes

Chronic exposure to manganese (Mn) leads to a neurological disorder, manganism, which shares multiple common features with idiopathic Parkinson disease (IPD). 17β-Estradiol (E2) and some selective estrogen receptor modulators, including tamoxifen (TX), afford neuroprotection in various experimental models of neurodegeneration. However, the neuroprotective effects and mechanisms of E2/TX in Mn-induced toxicity have yet to be documented. Herein, we studied the ability of E2/TX to protect rat cortical primary neuronal and astroglial cultures from Mn-induced toxicity. Cell viability, Western blot, and reactive oxygen species (ROS) generation were assessed. Results established that both E2 (10nM) and TX (1μM) attenuated Mn-induced toxicity. The protective effects of E2/TX were more pronounced in astrocytes versus neurons. The E2-mediated attenuation of Mn-induced ROS generation in astrocytes at 6-h treatment (where no cell death was detected) was mediated by a classical estrogen receptor (ER) pathway and the TX-mediated effect on Mn-induced ROS generation was not mediated via classical ER-dependent mechanisms and likely by its antioxidant properties. The phosphatidylinositol-3 kinase (PI3K)/Akt signaling pathway was involved in both E2- and TX-induced attenuation of Mn-induced ROS formation (6 h) in astrocytes. Treatments with Mn for a longer duration (24 h) led to significant cell death, and the protective effects of E2 and TX were (1) not mediated by a classical ER pathway and (2) associated with activation of both mitogen-activated protein kinase/extracellular signal-regulated kinase and PI3K/Akt signaling pathways. Taken together, the results suggest that both E2 and TX offer effective therapeutic means for neuroprotection against Mn-induced toxicity.
The effects of acute afterload change on systolic ventricular function in conscious dogs with normal vs. failing hearts.

Background: To date, no data exist on the linearity and, therefore, the usefulness of the preload recruitable stroke work (PRSW) and end-systolic pressure–volume (ESPVR) relationships during acute afterload changes in heart failure. Aims: Our aim was, therefore, to characterize both relationships in a model of ventricular pacing induced heart failure at baseline and during acute changes in afterload. Methods: Dynamic left ventricular volume and transmural pressure were measured in 10 conscious dogs using sonomicrometry and micromanometry under control conditions and during heart failure produced by 3 weeks of rapid right ventricular pacing. Afterload was varied from baseline with intravenous infusions of nitroprusside and phenylephrine. Left ventricular function was assessed using the PRSW and ESPVR relationships. Results: Cardiac output demonstrated a linear inverse relationship with afterload in both normal and failing hearts (r2>0.5, P 0.05). Conclusion: Thus, the PRSW and ESPVR relationships are insensitive to acute afterload changes in both failing and normal hearts, and the failing left ventricle is no more afterload-sensitive than the normal heart.