cssi/SciSciGPT-SciSciNet huggingface dataset:
MALIGNANT CELLULAR EVOLUTION: An Analysis of the Causation and Prevention of Cancer

The appearance of a cancerous strain of cells within the multicellular organism is thought of as analogous to the appearance of a new variant or species of animal or plant. This evolutionary concept of cancer is considered compatible with the epidemiological and pathological distribution of malignant tumors. Variability is visualized as an inescapable concomitant of every cell division. The action of viruses may be different from other mutagens. They may endow certain cells with a large competitive advantage. Growth and repair of tissues provide an opportunity for evolution of cells. Replacement of cells with lesser proliferative vigor by cells with greater vigor is the essential basis of evolutionary neoplasia. For example the adult neuron does not reproduce; therefore it does not become involved in malignant neoplasia. It is only by selection from serial reproduction t hat minute individual differences can be added to produce large deviations of heritable characteristics. This principal has been used by animal and plant breeders. Although formation of the glandular endometrium necessitates much serial reproduction menstruation may be regarded as a physiological eraser of endometrial neoplasia. With the menopause more progressive serial reproduction is possible. The effect of chronic irritation is much greater if replacement of cells is localized. Effects of ionizing radiation and tobacco smoke agree with t he concept of malignant cell evolution. This concept of malignant cellular evolution suggests that it is an inescapable concomitant of all multicellular life. The value of avoiding unnecessary exposure to mutagens is stressed.
Angle-resolved photoemission and temperature dependence of 5f electronics states in uranium nitride

Abstract A 5f-like photoemission feature in normal emission from UN(100) appears for T N e el = 53 K . It arises from band states that are modified due to a halving of the Brillouin zone in the antiferromagnetic phase. This is the first observation for f electrons and proves their itinerant character in UN.
Crystal growth of La2NaTaO6: A new monoclinically distorted double perovskite

Abstract Single crystals of La 2 NaTaO 6 were grown out of a reactive high-temperature hydroxide melt. The structure was determined by single crystal X-ray diffraction. La 2 NaTaO 6 adopts the monoclinically distorted double perovskite structure type with general formula A 2 BB′O 6 , where tantalum atoms are located on the B′ site. La 2 NaTaO 6 crystallizes in the monoclinic space group P2 1 /n with a= 5.6904(2) A, b =5.9824(2) A, c =8.1423(2) A and β =90.8650(10)°⋅ An optical bandgap of 4.5 eV was estimated from the UV–vis diffuse reflectance spectrum.
Effects of UV/H2O2 preoxidation on the aerobic biodegradability of quaternary amine surfactants

Abstract The purpose of this study was to examine the effect of UV/H 2 O 2 advanced oxidative pretreatment on the biodegradability of two major classes of quaternary amine surfactants. In this study, the biodegradability of unoxidized and oxidized solutions of quaternary amines were determined using BAS assays. UV/H 2 O 2 preoxidation effectively enhanced the biodegradability of alkyldimethylbenzyl ammonium chlorides (Barquats), but had little effect on the biodegradability of dioctyl-dimethyl ammonium chloride (Bardac LF).
Climate change, precipitation and impacts on an estuarine refuge from disease.

Background Oysters play important roles in estuarine ecosystems but have suffered recently due to overfishing, pollution, and habitat loss. A tradeoff between growth rate and disease prevalence as a function of salinity makes the estuarine salinity transition of special concern for oyster survival and restoration. Estuarine salinity varies with discharge, so increases or decreases in precipitation with climate change may shift regions of low salinity and disease refuge away from optimal oyster bottom habitat, negatively impacting reproduction and survival. Temperature is an additional factor for oyster survival, and recent temperature increases have increased vulnerability to disease in higher salinity regions. Methodology/Principal Findings We examined growth, reproduction, and survival of oysters in the New York Harbor-Hudson River region, focusing on a low-salinity refuge in the estuary. Observations were during two years when rainfall was above average and comparable to projected future increases in precipitation in the region and a past period of about 15 years with high precipitation. We found a clear tradeoff between oyster growth and vulnerability to disease. Oysters survived well when exposed to intermediate salinities during two summers (2008, 2010) with moderate discharge conditions. However, increased precipitation and discharge in 2009 reduced salinities in the region with suitable benthic habitat, greatly increasing oyster mortality. To evaluate the estuarine conditions over longer periods, we applied a numerical model of the Hudson to simulate salinities over the past century. Model results suggest that much of the region with suitable benthic habitat that historically had been a low salinity refuge region may be vulnerable to higher mortality under projected increases in precipitation and discharge. Conclusions/Significance Predicted increases in precipitation in the northeastern United States due to climate change may lower salinities past important thresholds for oyster survival in estuarine regions with appropriate substrate, potentially disrupting metapopulation dynamics and impeding oyster restoration efforts, especially in the Hudson estuary where a large basin constitutes an excellent refuge from disease.
Organizational Effects on First-Year Students' Academic Outcomes at a New Public Research University:

The relationship between organizational behavior and student outcomes has been understudied, especially in less selective public research universities and among students from underrepresented populations. This study draws on Berger and Milem’s (2000) framework to examine the relationship between student entry characteristics, organizational behavior, student experiences, and two early academic outcomes (GPA and academic development) for first-year students enrolled in a new public research university. Student entry characteristics were most strongly associated with GPA, while organizational characteristics and student experiences were most strongly associated with academic development, a measure of students’ perceptions of the extent to which the institution contributed to gains in their academic skills. Institutional emphases on academic and social engagement were found to be positively associated with academic development.
Rates and Predictors of Plans for Inferior Vena Cava Filter Retrieval in Hospitalized Patients

BACKGROUND Use of inferior vena cava (IVC) filters has been increasing over time. However, because of the increased risk of deep vein thrombosis with permanent filters, placement of retrievable filters has been recommended. Little is known about the factors associated with planned retrieval of IVC filters.
A PCR-Based Assay for Detection of Fusarium oxysporum f. sp. lactucae in Lettuce Seed

Mbofung, G. C. Y., and Pryor, B. M. 2010. A PCR-based assay for detection of Fusarium oxysporum f. sp. lactucae in lettuce seed. Plant Dis. 94:860-866. A nested polymerase chain reaction-based (nPCR) assay was developed and evaluated for the rapid detection of Fusarium oxysporum f. sp. lactucae in seed of lettuce. Three primers were designed from sequences of the intergenic spacer region of the rDNA and were used in the PCR amplifications. The first amplification employed the primer pair GYCF1 and GYCR4C and produced a product of 2,270 bp. The second amplification employed the forward primer GYCF1 and the nested primer R943 and produced a single 936-bp PCR product. The nPCR protocol developed successfully detected the target sequence in genomic DNA at 1 fg/µl. A seed assay was tested that included a 4-day incubation step in which seed were maintained under high humidity conditions to increase fungal biomass for DNA extraction. In seed lots prepared by mixing known amounts of F. oxysporum f. sp. lactucae–infested seed with noninfested seed, this assay permitted the detection of the pathogen from lots with infestation rates as low as 0.1%. Samples of lettuce seed obtained from 88 commercial lettuce seed lots were assayed for the pathogen by direct plating and by using the nPCR assay. The pathogen was not detected by either diagnostic method, suggesting the seed lots were pathogen free or the level was below detection limits.
Administration of a targeted cytotoxic analog of luteinizing hormone-releasing hormone inhibits growth of estrogen-independent MDA-MB-231 human breast cancers in nude mice.

Receptor targeted chemotherapy is less toxic and more effective than conventional chemotherapy. Receptors for luteinizing hormone-releasing hormone (LH-RH) are found in about 50% of human breast cancers. Highly potent cytotoxic radical 2-pyrrolinodoxorubicin (AN-201) was linked to the agonistic analog [D-Lys6]LH-RH to form cytotoxic LH-RH analog AN-207. We evaluated whether AN-207 could be targeted to the hormone-independent MDA-MB-231 human breast cancers. Nude mice bearing MDA-MB-231 tumors were injected i.v. with 250 nmol/kg doses of cytotoxic radical AN-201, cytotoxic LH-RH analog AN-207, the unconjugated mixture of AN-201 and carrier [D-Lys6]LH-RH, [D-Lys6]LH-RH alone and vehicle (control). The growth of MDA-MB-231 tumors in animals given a single dose of AN-207 was inhibited significantly (p=0.01) for 3 weeks after injection, whereas tumors in all the other groups grew steadily. All cytotoxic compounds produced leukopenia, but the strongest lymphocyte suppression was caused by cytotoxic radical AN-201. Three weeks after treatment, the presence of mRNA for LH-RH receptors was demonstrated by RT-PCR in all the groups and radioreceptor assays demonstrated high-affinity binding sites for LH-RH on tumor cell membranes of control animals and those treated with AN-201, the carrier peptide alone or in combination with AN-201. At this time point binding assays did not reveal the expression of membrane proteins in tumors treated with AN-207, but 60 days after administration of AN-207, high affinity LH-RH binding sites were found again in MDA-MB-231 tumors. These results indicate that cytotoxic LH-RH analog AN-207 could be utilized for receptor targeted chemotherapy of breast cancers expressing receptors for LH-RH.
Main techniques used in high pressure research with some selected examples

Abstract Various high pressure techniques are introduced, and their advantages in connection with certain measurement techniques are discussed. Selected examples of light scattering, energy dispersive X-ray diffraction, and absorption measurements are presented.
SITE-DEPENDENT REGULATION OF POPULATION SIZE:A NEW SYNTHESIS

The nature and extent of population regulation remains a principal unanswered question for many types of organisms, despite extensive research. In this paper, we provide a new synthesis of theoretical and empirical evidence that elucidates and extends a mechanism of population regulation for species whose individuals preemptively use sites that differ in suitability. The sites may be territories, refuges from predation, oviposition sites, etc. The mechanism, which we call site dependence, is not an alternative to density dependence; rather, site dependence is one of several mechanisms that potentially generate the negative feedback required for regulation. Site dependence has two major features: (1) environmentally caused heterogeneity among sites in suitability for reproduction and/or survival; and (2) preemptive site occupancy, with the tendency for individuals to move to sites of higher quality as they become available. Simulation modeling shows that these two features, acting in concert, generate nega...
Xylitol mediated amelioration of acetylphenylhydrazine-induced hemolysis in rabbits

Xylitol was investigated for its ability to ameliorate hemolytic anemia induced by acetylphenylhydrazine in rabbits. Animal experiments were performed using two different concentrations of xylitol, a 5% and a 10% solution with a total dose of 2 g/kg body weight and infusion rates of 10 mg and 20 mg xylitol per kg body weight per minute respectively. Two doses of acetylphenylhydrazine (APH), 5 and 10 mg per kg, were injected intraperitoneally as hemolytic inducers in different groups of rabbits. All the rabbits infused with xylitol showed significantly less acute APH-induced hemolysis. The isotonic 5% xylitol solution was found to maintain and restore the hematological parameters (packed cell volume, hemoglobin concentration, reduced glutathione (GSH) content, and reticulocyte counts) better than the 10% xylitol solution. Increased 51CR-red cell survival confirmed the beneficial effect of xylitol. The survival of erythrocytes as represented by chromium-labeling in rabbits infused with 5% xylitol after treatment with 10 mg/kg APH increased from about 33% (the survival of red cells in rabbits injected with APH alone) to 67% of normal rabbits' red cell survival. Erythrocytes in APH-treated animals took up xylitol more readily than erythrocytes from control animals. Our results in rabbits suggest that (1) non-toxic dosage of xylitol is effective in ameliorating the hemolytic episode induced by APH, (2) there is a dose relationship between the hemolytic effect induced by APH and the preventive effect offered by xylitol, (3) drug-challenged cells effectively acquired two to three fold more xylitol to compensate for the cellular needs than that of the normal cells, and (4) sufficient xylitol (55 mg/dl) to act as substrate for xylitol dehydrogenase was recovered intracellularly in drug-challenged rabbit erythrocyte in vivo, in spite of a low plasma (<30 mg/dl) concentration of the substrate. This antihemolytic affect of xylitol is likely accomplished through NADPH generation, which maintains the level of GSH and protects the hemoglobin and other structural and functional proteins against peroxidative damage.
The enhancement of schedule-induced polydipsia by preschedule noncontingent shock

Eight food-deprived female albino rats, with electrode attachments to the back of their necks, were divided into two groups, a shock-before-schedule group and a no-shock-before-schedule group, with four Ss in each group. Ss were subjected to five successive experimental phases, during each of which individual water intakes were recorded for each 200-min daily session. The predicted result, that electric shock preceding the reinforcement schedule condition would lead to increases in water intakes, was generally upheld by the data. Increases in drinking associated with shock appeared to be a result of both increased frequency of drink bout initiation and a lengthening of the lick burst.
Oxidative phosphorylation in pseudomonas saccharophila under autotrophic and heterotrophic growth conditions

Summary Cell-free extracts obtained from heterotrophically or autotrophically grown Pseudomonas saccharophila catalyzed phosphorylation coupled to the oxidation of generated-NADH yielding P/O ratios of 0.9 – 1.2. Succinate oxidation was also coupled to phosphorylation but the P/O ratios were poor in the autotrophic system. Moreover, in the latter system the oxidation of exogensously added NADH was not coupled to ATP synthesis. The autotrophic system in addition appears to lack the terminal energy-coupling site. Although the oxidation of H 2 yielded P/O ratio of 0.5 – 0.7, the entry of electrons from H 2 occurred predominantly at the level of cytochrome b . The phosphorylation with H 2 or succinate was unaffected by rotenone; the latter compound however, markedly inhibited the NADH-linked phosphorylation. The oxidative phosphorylation with H 2 , NADH, and succinate was sensitive to antimycin A, cyanide, and to various uncoupling agents.
Primary hyperoxaluria 1: catch up growth and normalization of oxaluria 6 years after hepatorenal transplantation in a prepubertal boy.

We present data on urinary oxalate (UOX), renal function, growth and bone age in a 10-year-old male with primary hyperoxaluria type 1. The patient had undergone combined liver-kidney transplantation at the age of 4.5 years. UOX increased up to 104 μmol/24 h after transplantation and declined to normal values thereafter. Excessive UOX concentrations after surgery might have been due to a bone pool of unsoluble oxalate and declined spontaneously. Creatinine clearance remained stable during observation period. The boy showed significant catch up growth. Height standard deviation score for chronological age improved from −2.4 before transplantation to −0.3 after 6 years. Radiological bone density improved at the same time.
Concentration photovoltaic–thermal energy co-generation system using nanofluids for cooling and heating

Abstract New designs of dual concentration photovoltaic–thermal (CPV/T) systems can provide both electrical and thermal energy, while reducing solar cell material usage via optical techniques. The overall system efficiency can be improved by using advanced dual-purpose liquids with enhanced heat transfer characteristics, such as nanofluids. In this paper the use of nanofluids, i.e., dilute nanoparticle suspensions in liquids, are considered for improved efficiency of a CPV/T system for the first time. Specifically, a 2-D model coupling thermal analysis and computational fluid dynamics simulations has been developed to calculate efficiencies of individual subsystems as well as the overall system. A new thermal conductivity model for nanofluids, which was validated with experimental data sets, was employed. The electrical and thermal performances of the system were evaluated for different climatic conditions. The results show that using nanofluids improves the electrical and total efficiencies of the system, especially when using silicon solar cells. For example, if the nanofluid outlet temperature of the solar cell is set to 62 °C via a controlled flow rate, the system overall efficiency could reach 70% with electrical and thermal contributions amounting to 11% and 59%, respectively. In summary, a nanofluid-based system is preferable to water-based systems in the long run.
CELLULAR IMMUNITY IN VITRO : CLONAL PROLIFERATION OF ANTIGEN-STIMULATED LYMPHOCYTES

When sensitive lymphocytes are cultured with the appropriate antigen, lymphoblasts appear after 24–48 hr of incubation and the number of these increases steadily from the 2nd to the 6th or 7th day. Our problem was to discover, at a cellular level, how this increase takes place; whether it is a massive response of many cells, stepwise recruitment of cells into the lymphoblast class, or simply repeated division of a few cells to form clones. In these experiments lymphocytes were incubated with antigen in culture tubes for 2–4 days and then a few cells, usually less than 200, were transferred to special microchambers for further culture. In these microchambers the cells could be viewed continually with a microscope and their fate recorded over the next 3–5 days by time-lapse cinemicrography. Examination of the film produced in this way showed that lymphoblasts divided and redivided to produce clones of 64 cells or more. It was possible to measure generation times from the film for 301 cells; the majority were between 8 and 13 hr but the range was 7.5–38.0 hr. There was no clear difference between generation times of human lymphocytes stimulated with tuberculin, streptokinase-streptodrnase, extract of the American pokeweed, or in the mixed leukocyte reaction. Similar times were also found for rat cells in the mixed leukocyte reaction. While these observations show that clonal proliferation does occur and could reasonably account for all the increase of lymphoblasts in lymphocyte cultures, the experiments, because of their design, do not exclude the possibility that other mechanisms such as recruitment may play a role as well, particularly during the first 48 hr after contact between sensitive cells and antigens.
A school mascot walks into the library: tapping school spirit for library instruction videos

Purpose – This paper aims to describe the University of Idaho Library's efforts to develop instructional videos starring the school mascot, Joe Vandal, and integrate these videos across the curriculum using the university's course management system. Video development, implementation in library instruction courses, and student and faculty assessment are discussed.Design/methodology/approach – The video creation process is described thoroughly, with an eye towards best practices, for those libraries that may wish to develop their own videos. Applications for implementation outside library instruction are also discussed.Findings – Although costly, professional‐quality videos are an engaging and effective way to reach students. Students at the University of Idaho found the library's instructional videos, starring the school mascot, to be entertaining, informative, and easy to understand.Research limitations/implications – The longitudinal effect of the videos on information literacy instruction has yet to be ...
A BLOCK MATRIX REPRESENTATION OF PERMUTATION NETWORKS

This work provides a mathematical framework for topologically-independent analysis of permutation networks. First, a structure-dependent representation is provided using matrices whose entries are switching expressions. Then, a transformation is presented which maps these matrices into structure-independent representations which are matrices whose entries are 0/1 matrices. Algebraic tools for manipulating the second type of matrices are also provided. Notions such as permutations realizable by a network, the rearrangeability property, and series and parallel connections of networks are defined and discussed with regard to the proposed representations.
Science in the Classroom: Finding a Balance Between Autonomous Exploration and Teacher-Led Instruction in Preschool Settings

Research Findings: This paper reports on children's use of science materials in preschool classrooms during their free choice time. Baseline observations showed that children and teachers rarely spend time in the designated science area. An intervention was designed to “market” the science center by introducing children to 1 science tool, the balance scale. Baseline measures showed that children did not know the scale's name or function. The intervention was expected to increase children's use of the science area and their knowledge about the scale. Children's voluntary presence and exploration in the science area increased after the balance scale intervention compared to in comparison classrooms. Furthermore, children who participated in this intervention demonstrated improved knowledge about the scale's function, whereas students in the comparison group did not. Practice or Policy: Adults can increase children's autonomous exploration of science tools and materials, and their knowledge about them, by of...
Unraveling the mysteries of the AV node.

v e s c t g n e e c u e a v d c c 3 a w r a i I s a r a n t t p a v e m q i t t p o The AV node is perhaps the most complicated structure n the heart, both anatomically and physiologically. Decades f research have identified unique properties related to AV odal physiology. One of these properties—the presence of ual AV nodal physiology—has been of particular interest ecause of its affiliation with the most common cause of aroxysmal supraventricular tachycardia, namely, AV nodal eentrant tachycardia (AVNRT), and the development of atheter ablation approaches targeting specific physiologic athways. Dual AV nodal physiology is “easily” recognized y the presence of a discontinuity in the AV nodal function urve. Because of the rapid and slower conduction times in hese pathways, they have come to be known as the “fast” nd “slow” pathways, respectively, although there are no uch histologic classifications. Retrograde activation of hese pathways has been more interesting because in addiion to a large increase in conduction time, the sequence of ctivation generally switches from the anterior portion of he triangle of Koch to the posterior portion. All sorts of ariants of AVNRT have been reported with varying paterns of retrograde atrial activation. While our observations to date regarding retrograde trial activation have been extensive, they have been limited y where we have looked. Much of our understanding and nowledge of human cardiac electrophysiology has arisen rom the wealth of information that can be deduced from lectrical recordings from the right atrium, right ventricle, nd coronary sinus, all of which can be easily accessed hrough the venous system, a routine procedure performed or diagnostic electrophysiologic testing. Because access to he left atrium and left ventricle is more complex, this has nly been performed in small numbers of patients when linically indicated, but rarely to study “right-sided” pheomena. However, we have learned over the years that even ight-sided phenomena can involve the left side of the sepum. For example, although the His bundle electrogram can lmost uniformly be recorded on the right side, successful is bundle ablation can only be achieved from the left in a ignificant fraction of patients. Similarly, only recently has he importance of mapping the left side of the atrial septum or septal atrial tachycardias been recognized. Katritsis et l have clearly shown that the left side of the septum is also
LDH isozymes during early hepatic regeneration

Abstract During the first 96 hours of regenerative growth following partial hepatectomy, liver lactate dehydrogenase showed a decreased affinity for deamino nicotinamide adenine dinucleotide and 3-acetyl pyridine deamino nicotinamide adenine dinucleotide together with an increase in the relative proportion of anodal tetramers and a decrease in the cathodal tetramers.
COMPARISON OF THE 2007 AND 2011 APPROPRIATE USE CRITERIA FOR TRANSTHORACIC ECHOCARDIOGRAPHY IN VARIOUS CLINICAL SETTINGS

The 2007 Appropriate Use Criteria (AUC) for echocardiography was revised in 2011 to cover a wider range of scenarios of use. We hypothesized that the 2011 AUC would better classify transthoracic echocardiograms (TTE) and allow a more accurate determination of the rate of appropriate TTE ordering.
Frameless stereotactic aspiration and thrombolysis of deep intracerebral hemorrhage is associated with reduction of hemorrhage volume and neurological improvement

Introduction: This ia a phase-2 safety trial to demonstrate the ability of frameless stereotactic aspiration and thrombolysis of ICH to safely remove blood.
Permittivity of dielectric-conductor mixture: application of logarithmic law of mixing to electric susceptibility

Based on the logarithmic law of mixing, a closed-form expression to calculate the permittivity of a composite material constituted by a dielectric dispersed with shaped metallic inclusions, is derived. Computed results are compared to available data.
Differential Role of Two-Component Regulatory Systems ( phoPQ and pmrAB ) in Polymyxin B Susceptibility of Pseudomonas aeruginosa

Polymyxins are often considered as a last resort to treat multidrug resistant P. aeruginosa but polymyxin resistance has been increasingly reported worldwide in clinical isolates. Polymyxin resistance in P. aeruginosa is known to be associated with alterations in either PhoQ or PmrB. In this study, mutant strains of P. aeruginosa carrying amino acid substitution, a single and/or dual inactivation of PhoQ and PmrB were constructed to further understand the roles of PhoQ and PmrB in polymyxin susceptibility. Polymyxin B resistance was caused by both inactivation and/or amino acid substitutions in PhoQ but by only amino acid substitutions of PmrB. Alterations of both PhoQ and PmrB resulted in higher levels of polymyxin B resistance than alteration of either PhoQ or PmrB alone. These results were confirmed by time-killing assays suggesting that high-level polymyxin resistance in P. aeruginosa is caused by alterations of both PhoQ and PmrB.
A computation procedure for the exact solution of location-allocation problems with rectangular distances

A method is presented to locate and allocate p new facilities in relation to n existing facilities. Each of the n existing facilities has a requirement flow which must be supplied by the new facilities. Rectangular distances are assumed to exist between all facilities. The algorithm proceeds in two stages. In the first stage a set of all possible optimal new facility locations is determined by a set reduction algorithm. The resultant problem is shown to be equivalent to finding the p-median of a weighted connected graph. In the second stage the optimal locations and allocations are obtained by using a technique for solving the p-median problem.
Electric Field Stimulates Angiogenesis via Activation of MAPK/ERK Signaling in Microvascular Endothelial Cells

Different types of physiological amplitude (40–250 mV/mm) [1] electric fields (EFs) have been shown to influence a wide variety of biological systems [2] and have been used as a therapeutic tool for tissue repair [3]. There has been emerging evidence that certain types of EFs can promote angiogenesis and tissue vascularization [4]. Studies have shown that direct current EF and pulsed EF induced angiogenic responses including cell migration, VEGF release and cytoskeletal reorganization in human endothelial cells (HUVECs) [4, 5]. Similarly different types of EF induced the activation of intracellular MAPK pathways in several non-endothelial cell types. [6, 7]. However, the effect of EF with different modalities on endothelial angiogenic responses and the intracellular pathways remain unknown.Copyright © 2012 by ASME
Activation Volumes of Carbon Diffusion in fcc Iron-Nickel Alloys

The disaccommodation technique was used to determine the activation volume of carbon diffusion, $\ensuremath{\Delta}V$, in six fcc iron-nickel alloys. Measurements were made at temperatures ranging from 68 to 90 \ifmmode^\circ\else\textdegree\fi{}C and pressures up to 6 kbar on samples having a nickel content between 31 and 63 at.%. A maximum activation volume of 3.9 ${\mathrm{cm}}^{3}$/mole was found at 34 at.% nickel. The compositional dependence of $\ensuremath{\Delta}V$ is satisfactorily reproduced by a magnetic-energy continuum model in which it is assumed that the activation free energy of diffusion is essentially ferromagnetic in origin.
Service versus Education, What Are We Talking About?

Objective To investigate the degree of variability in perception as related to the service versus education issue in general surgery residency education. Study Design A survey questionnaire was designed with 15 scenarios constructed by the author to represent an array of resident experiences with differing educational and noneducational value. After appropriate Institutional Review Board (IRB) approval, the survey was administered to a variety of medical student, resident, and faculty groups. Individual and intergroup variability was assessed. Setting Large, university-affiliated teaching hospital. Results A total of 137 questionnaires were returned from medical students, residents, and attending physicians encompassing several medical specialties and a broad range of clinical experience. In all, 7 of 15 scenarios resulted in statistically significant different response patterns across specialties and 8 of 15 scenarios across levels of experience. Individual responses spanned nearly all possible responses for most scenarios. Conclusions Considerable variability exists across individuals as well as groups in the interpretation of the types of experiences that represent service, education, or both in general surgery residency training. Arriving at a quantifiable balance in service versus education in general surgery resident education may never be possible given the variability in interpretation of the various activities residents perform. This must be kept in mind in both interpreting the results of the Accreditation Council for Graduate Medical Education (ACGME) survey and also when designing educational activities within a program.
Ideal barriers to polarization reversal and domain-wall motion in strained ferroelectric thin films

The ideal intrinsic barriers to domain switching in $c$-phase ${\text{PbTiO}}_{3}$ (PTO), ${\text{PbZrO}}_{3}$ (PZO), and ${\text{PbZr}}_{1\ensuremath{-}x}{\text{Ti}}_{x}{\text{O}}_{3}$ (PZT) are investigated via first-principles computational methods. The effects of epitaxial strain on the atomic structure, ferroelectric response, barrier to coherent domain reversal, domain-wall energy, and barrier to domain-wall translation are studied. It is found that PTO has a larger polarization, but smaller energy barrier to domain reversal, than PZO. Consequentially the idealized coercive field is over two times smaller in PTO than PZO. The Ti-O bond length is more sensitive to strain than the other bonds in the crystals. This results in the polarization and domain-wall energy in PTO having greater sensitivity to strain than in PZO. Two ordered phases of PZT are considered, the rocksalt structure and a (100) PTO/PZO superlattice. In these simple structures we find that the ferroelectric properties do not obey Vergard's law, but instead can be approximated as an average over individual five-atom unit cells.
Effect of Supplementing Predominantly Roughage Rations with Oats Grass, Trace Minerals, or B-Vitamins on Nutrient Utilization,

Abstract Twenty-four wethers were utilized in a 2 × 2 × 2 factorial experiment with three replicates, to determine the effects of trace minerals, B-vitamins, and hydroponically produced oats grass on a high-roughage diet. Addition of oats grass had no effect on the digestibilities of any nutrients. When trace minerals were added to the ration, the digestion coefficient for nitrogen-free extract was increased significantly (P Addition of oats grass resulted in a narrowing of the acetate-to-propionate ratio (P Blood ammonia and urea levels were not affected significantly when oats grass was present. Similarly, addition of trace minerals and B-vitamins plus vitamin E had no effect on the rumen ammonia levels or rumen pH.
Cathepsin G activates protease-activated receptor-4 in human platelets.

Of the four known protease-activated receptors (PARs), PAR1 and PAR4 are expressed by human platelets and mediate thrombin signaling. Whether these receptors are redundant, interact, or play at least partially distinct roles is unknown. It is possible that PAR1 and/or PAR4 might confer responsiveness to proteases other than thrombin. The neutrophil granule protease, cathepsin G, is known to cause platelet secretion and aggregation. We now report that this action of cathepsin G is mediated by PAR4. Cathepsin G triggered calcium mobilization in PAR4-transfected fibroblasts, PAR4-expressingXenopus oocytes, and washed human platelets. An antibody raised against the PAR4 thrombin cleavage site blocked platelet activation by cathepsin G but not other agonists. Desensitization with a PAR4 activating peptide had a similar effect. By contrast, inhibition of PAR1 function had no effect on platelet responses to cathepsin G. When neutrophils were present, the neutrophil agonist fMet-Leu-Phe triggered calcium signaling in Fura-2-loaded platelets. Strikingly, this neutrophil-dependent platelet activation was blocked by the PAR4 antibody. These data show that PAR4 mediates platelet responses to cathepsin G and support the hypothesis that cathepsin G might mediate neutrophil-platelet interactions at sites of vascular injury or inflammation.
The spectral transform in the semiclassical limit of a finite discrete NLS chain

The direct eigenvalue problem associated with an "inverse scattering" method for a finite nonlinear Schrodinger chain is studied in the semiclassical limit. In the case that the initial data for the chain are less than unity in modulus, the eigenvalue problem is unitary and the associated norming constants are real-valued. Formal asymptotic (WKB) analysis is performed, and formulas for the asymptotic spectral density and norming constants are obtained. They are supported by known facts about the discrete transform, rigorous asymptotics and numerical calculations.
CaMKII uses GTP as a phosphate donor for both substrate and autophosphorylation

The vast majority of serine/threonine protein kinases have a strong preference for ATP over GTP as a phosphate donor. CK2 (Casein kinase 2) is an exception to this rule and in this study we investigate whether calcium/calmodulin-dependent protein kinase II (CaMKII) has the same extended nucleotide range. Using the Drosophila enzyme, we have shown that CaMKII uses Mg2+GTP with a higher Km and Vmax compared to Mg2+ATP. Substitution of Mn2+ for Mg2+ resulted in a much lower Km for GTP, while nearly abolishing the ability of CaMKII to use ATP. These similar results were obtained with rat αCaMKII, showing the ability to use GTP to be a general property of CaMKII. The Vmax difference between Mg2+ATP and Mg2+GTP was found to be due to the fact that ADP is a potent inhibitor of phosphorylation, while GDP has modest effects. There were no differences found between sites autophosphorylated by ATP and GTP, either by partial proteolysis or mass spectrometry. Phosphorylation of fly head extract revealed that similar proteins are substrates for CaMKII whether using Mg2+ATP or Mg2+GTP. This new information confirms that CaMKII can use both ATP and GTP, and opens new avenues for the study of regulation of this kinase.
NASA Langley Mach 6 quiet wind-tunnel performance

The flow in the NASA Langley Mach 6 quiet wind tunnel has been investigated to quantify the effectiveness of laminar-flow control techniques used to delay transition of the nozzle-wall boundary layer. The results of this investigation include an assessment of the mean and unsteady nozzle flow to define the quiet core length, and hence performance, over the operating range of the facility. A large, uniform region of Mach 5.91 flow was documented for a variety of unit Reynolds numbers. By using a prototype constant-voltage anemometer to measure the unsteady flowfield, acoustic radiation patterns from the transitional nozzle-wall boundary layers were mapped. These disturbances originating at the Irregular edge of the transitional nozzle-wall boundary layer were shown to follow Mach lines into the test section of the nozzle, thereby limiting the length of the quiet core. With a virtual origin downstream of the nozzle throat, a Reynolds number dependency was found for the amplitudes of the acoustic radiation.
Dynamical response functions due to pulse solitons in the isotropic ferromagnetic Heisenberg chain in an external magnetic field

Dynamical correlation functions are evaluated for the classical, isotropic, ferromagnetic Heisenberg chain in an external magnetic field. The calculation is approximate, using as its basis an ideal gas of ballistic pulse-soliton excitations which are known to be exact solutions to the spin equations of motion in the continuum limit. For the longitudinal correlation function (i.e. parallel to the applied field) a central peak structure is found which becomessplit at sufficientlylow temperatures and smears to higher frequence with increasing temperatures. This behaviour is contrasted with that found in the sine-Gordon and related solition systems. Comparisons with the results of numerical simulations of the Heisenberg chain are made, and the possible relevance to magnetic chain materials such as CsNiF3 is discussed.
Craniovertebral junction abnormality in a case of Joubert syndrome

Joubert syndrome (JS) is a genetically heterogeneous autosomal recessive disorder [1] characterized by hypotonia, ataxia, early developmental delay, and characteristic findings on radiographic imaging of the brain. JS has an estimated prevalence of one case in 100,000 [2, 3], and was described in 1969 by Joubert et al. [4]. While there are hallmark features to JS, the phenotypic presentation can vary and overlap with a group of disorders [5] that involve dysfunction in cilia-related proteins [6]. These disorders are known as the ciliopathies and include Bardet–Biedl syndrome (BBS) [7], Meckel–Gruber syndrome (MKS) [2], Senior–Loken syndrome [8], and JS. The ciliopathies frequently present with central nervous system abnormalities that include abnormal cerebellar dysfunction and morphogenesis [9]. Cilia-related genes in the developing cerebellum and pontomedullary junction involve Wnt and sonic hedgehog (Shh) signaling [10] which help to pattern the posterior fossa and brainstem [11]. JS is associated with mutations in a number of genetic loci [3] implicated in cilia-related function [6, 8]. There are several JS subtypes with known genetic loci [2] that present with a variety of CNS anomalies including cerebellar and midbrain dysmorphogenesis and cortical polymicrogyria [8]. Despite the genetic characterization, the underlying mutation frequency for each of the genes associated with JS is less than 10% [3] with fewer than 50% of JS patients having an identified mutation. There are, however, cardinal clinical features that can be used to identify JS patients. They will present most frequently with hypotonia, ataxia, developmental delay, respiratory, or ocular abnormalities [12]. Patients will have characteristic findings on brain MRI including: widened interpeduncular fossa, thickened superior cerebellar peduncles, and hypoplasia of the vermis [13]. We describe a case of a JS patient presenting with craniocervical spine involvement and progressive scoliosis. To the best of our knowledge, this is the first known case describing JS with an associated craniovertebral junction (CVJ) abnormality.
A polynucleotide CD probe: Interactions with oligomers of a polycationic amine that exhibit positive extrinsic bands at > 300 nm

A set of large positive extrinsic CD bands ([θ]333 = 2.6 X 104 deg-cm2/decimole phosphate) in the > 300 nm region as well as diminution of the intrinsic signals (θ275) have been observed in the CD spectra of various nucleic acids complexed with the achiral compound, N-poly{α-[N-(4-pyridylethylene-4-pyridyl-N′-)α′-p-xylyl]dibromide}-4-pyridylethylene-4-pyridinium bromide, (polymer X).1,2,5 The signal changes are attributed to the binding of polymer X chromophores isogeometrically to the DNA helix in an ordered chiral arrangement. Fractionation of polymer X gives 10 well-separated oligomers. The oligomers were characterized by nmr. Their interactions with DNA have been investigated with respect to r(r = ratio of equivalents of polymer X charge/g-atoms DNA phosphorus) and n (oligomer chain length). In all cases where n ≥ 1, [θ]333 increases linearly with increasing r between 0 and 0.32, and is accompanied by a corresponding decrease in [θ]275, which becomes negative as r approaches .32. Extrinsic band intensities reveal a dependence on n up to n = 5, above which increases in nonspecific binding result in a reduction in normalized band intensities. Polymer X shows a strong preference for B-form nucleic acids and induces maximum extrinsic CD signal intensities with A-T homopolymers. Alterations in helix hydration are believed to accompany complex formation. Inversions in [θ]275 of the octamer X-poly(dA-dT) complex have been attributed to the “alternating B” conformation of poly(dA-dT).3 Similar inversions are not observed in other nucleic acid-octamer X complexes. Visible and CD spectrometry data from competition studies in the presence of the antibiotics actinomycin D (AMD), daunomycin (DM), and distamycin A (DST) are consistent with “nonclassical” intercalation as the mode of binding, and these data place the potential binding site in or near the hydrophobic region of the minor groove. Reductions in [θ]333 with increasing urea further implicate the involvement of hydrophobic interactions in the formation of an asymmetric complex. Stabilization of the helix results in all cases as evidenced by alterations in Tm; corresponding changes, however, in cooperativity are not clearly discernable. Viscosity and light-scattering data indicate no changes in molecular weight due to aggregation, and as such are not consistent with a transition to the ψ-DNA upon complex formation.
The permeability of the Antarctic vortex edge

Mixing and cross-vortex mass transport along isentropic surfaces in the lower stratosphere are investigated with a 'contour advection' technique and a semi-Lagrangian transport model for the Antarctic winter of 1993 using analyzed winds from the United Kingdom Meteorological Office data assimilation system. Results from the 'contour advection' technique show that at the vortex edge there exists a potential vorticity (PV) contour that has the smallest lengthening rate. This PV contour is referred to as the 'line of separation' because it essentially separates the inner and outer vortex. The average e-folding time for the lengthening of the 'line of separation' increases monotonically with altitude, ranging from about 7 days on the 350 K isentropic surface to about 105 days on the 500 K isentropic surface. The results also suggest the existence of a transition layer around the 400 K isentropic surface, above which the vortex is nearly completely isolated from the midlatitudes and below which the vortex is less isolated. Results from a semi-Lagrangian transport model with an idealized tracer initially inside the inner vortex show that at 425 K and above virtually no tracer is transported out of the vortex during a 40-day integration starting from July 21, 1993. At 400 K and below a small amount of the tracer is transported out of the vortex while the bulk of the tracer remains confined within the inner vortex.
Vacuum polarization in a strong external field

Vacuum polarization in the field of a high-Z finite-size nucleus is examined, and the polarization charge density in coordinate space of order alpha(Z alpha)exp n not less than 3 is calculated. Energy-level shifts of K- and L-shell electrons in hydrogenlike systems are given.
On a diagonal Padé approximation in two complex variables

A special type diagonal Pade approximation for a class of hermitian power series in two variables is related to a canonical strong-operator topology, finite-rank approximation of cyclic operators. The expected convergence of the process (uniform or in measure) is derived from operator theory facts.
Cyclic AMP-dependent Activation of Rap1b

Rap1 proteins belong to the Ras superfamily of small molecular weight GTP-binding proteins. Although Rap1 and Ras share approximately 50% overall amino acid sequence identity, the effector domains of the two proteins are identical, suggesting either similar or antagonistic signaling roles. Several pathways leading to Ras activation have been defined, including those initiated by agonist binding to tyrosine kinase or Gi-coupled receptors. Nothing is known about such events for Rap1 proteins. The cAMP-mediated inhibition of Ras-dependent MAP kinase activation is well documented and resembles that caused by expression of GTPase-deficient Rap1. We have developed a system whereby signals leading to Rap1b activation, i.e. an increase in Rap1b-bound GTP/GDP ratio, can be measured. We report here that treatment of cells with agents that elevate intracellular cAMP levels result in Rap1b activation. These results demonstrate for the first time agonist-dependent activation of Rap1 proteins.
Silicone Elastomere Ring Vertical Gastroplasty: extended follow-up.

Statistically significant long-term data have been noticeably scarce in the evaluation of various bariatric procedures. Bariatric patients who lose weight frequently experience drastic life-style changes and often exhibit denial to the extent that follow-up is impaired. In this study, a cohort of 100 consecutive patients who underwent silicone elastomere ring vertical gastroplasty is evaluated at 46-55 months post-surgery with 90% follow-up. Results indicate that the 24-month figure of 36% loss of the preoperative weight level deteriorates to 32% at 46-55 months, and the failure rate increases slightly to 25% (or less), primarily due to anatomic failure of the procedure. Failure due to lack of patient compliance occurs but is less common than previously thought. Silicone elastomere ring vertical gastroplasty remains one of the safest of the effective procedures available to the bariatric surgeon.