cssi/SciSciGPT-SciSciNet huggingface dataset:
Black Plane Solutions and Localized Gravitational Energy.

We explore the issue of gravitational energy localization for static plane-symmetric solutions of the Einstein-Maxwell equations in 3+1 dimensions with asymptotic anti-de Sitter behavior. We apply three different energy-momentum complexes, the Einstein, Landau-Lifshitz, and Moller prescriptions, to the metric representing this category of solutions and determine the energy distribution for each. We find that the three prescriptions offer identical energy distributions, suggesting their utility for this type of model.
CLINICAL AND NECROPSY FINDINGS ASSOCIATED WITH INCREASED MORTALITY AMONG AMERICAN ALLIGATORS OF LAKE GRIFFIN, FLORIDA

From December, 1997, through November, 2000, 306 deaths were documented among adult and subadult American alligators (Alligator mississippiensis) of Lake Griffin, Florida (USA). Some live alligators were lethargic and unresponsive to approach. To determine the cause, we examined ten alligators captured from Lake Griffin between December 1997 and June 1999. Initially, four alligators, three of which were clinically unresponsive, were sacrificed for routine diagnostic necropsy. The other six Lake Griffin alligators, and five control alligators captured from Lake Woodruff National Wildlife Refuge, Florida, where mortality was negligible, were studied extensively by clinical neurologic examination, electromyography, hematology, serum chemical analyses, and blood culture, then sacrificed and necropsied. Samples of brain, spinal cord, peripheral nerves, skeletal muscle, and major internal organs were examined by light microscopy for abnormalities. Samples of nervous tissue also were examined by electron microscopy, and samples of various tissues were collected for toxicologic analyses. Clinical signs included swimming in circles, inability to submerge, lethargy, weakness, unresponsiveness, slow reflexes, dragging the dorsal surfaces of the hind feet, head tilt, and anisocoria. Lake Griffin alligators had significantly lower distal sciatic nerve conduction velocities than Lake Woodruff alligators, and the most severely affected alligators had the lowest velocities; but morphologic abnormalities in peripheral nerves were not evident in most cases. Three severely affected alligators had acute focal necrosis of the torus semicircularis in the midbrain, two had skeletal myofiber atrophy, another had diffuse nonsuppurative encephalomyelitis, and one mildly affected alligator had skeletal myodegeneration. The cause or causes have not yet been identified.
Completed suicide among older patients in primary care practices: a controlled study

OBJECTIVE: To determine whether physical and psychiatric illness, functional status, and treatment history distinguish older primary care patients who committed suicide from those who did not. DESIGN: A case-control study using data collected by psychological autopsies of suicides and prospective patient interviews for controls. SETTING: Primary care practices in Monroe County, NY. PARTICIPANTS: Forty-two suicides aged 60 years and older who visited a primary care provider within 30 days of death and 196 patients aged 60 years and older from a group practice of general internal medicine (n = 115) or family medicine (n = 81). MEASUREMENTS: Psychiatric diagnosis; depressive symptom severity; physical health and function; psychiatric treatment history. RESULTS: Completed suicides had more depressive illness (P = .001), physical illness burden (P = .0002), and functional limitations (P = .0001) than controls and were more likely to be prescribed antidepressants (P = .004), anxiolytic agents (P = .0001), and narcotic analgesics (P = .022). Among depressed subjects, affective symptom severity (P < .0001) and emotional dysfunction (P < .0001) distinguished suicide completers. However, physical health, overall function, and treatments received did not differ between groups. CONCLUSIONS: The primary care setting is an important venue for late life suicide prevention. Primary care providers should be well prepared to diagnose and treat depression in their older patients. Additional research is needed concerning the interactions of physical health, functional status, and depressive symptoms in determining suicide risk. J Am Geriatr Soc 48: 23–29, 2000.
The sorption of rare earths on anion exchange resins from nitric acid-mixed solvent systems

The sorption of lanthanum, dysprosium, and ytterbium on anion exchange resins from nitric acid-isopropyl alcohol-water mixtures was studied in detail. The distribution function of lanthanum shows a maximum that appears to be caused by the invasion of isopropyl alcohol into the resin phase at high mole fractions of alcohol. This is supported by indirect evidence obtained from the effects of polarity of organic solvent, temperature, cross-linkage of resin, and complexing agent on the distribution functions. The size of the maximum decreases as the atomic number increases, and as a result, large differences in distribution coefficients are obtained at high mole fractions of alcohol. The separation of the rare earths by use of Amberlite IRA 400 resin and 0·5 M HNO3-95 per cent isopropyl alcohol eluent is suggested.
WE-E-17A-01: Characterization of An Imaging-Based Model of Tumor Angiogenesis

Purpose: Understanding the transient dynamics of tumor oxygenation is important when evaluating tumor-vasculature response to anti-angiogenic therapies. An imaging-based tumor-vasculature model was used to elucidate factors that affect these dynamics. Methods: Tumor growth depends on its doubling time (Td). Hypoxia increases pro-angiogenic factor (VEGF) concentration which is modeled to reduce vessel perfusion, attributing to its effect of increasing vascular permeability. Perfused vessel recruitment depends on the existing perfused vasculature, VEGF concentration and maximum VEGF concentration (VEGFmax) for vessel dysfunction. A convolution-based algorithm couples the tumor to the normal tissue vessel density (VD-nt). The parameters are benchmarked to published pre-clinical data and a sensitivity study evaluating the changes in the peak and time to peak tumor oxygenation characterizes them. The model is used to simulate changes in hypoxia and proliferation PET imaging data obtained using [Cu- 61]Cu-ATSM and [F-18]FLT respectively. Results: Td and VD-nt were found to be the most influential on peak tumor pO2 while VEGFmax was marginally influential. A +20 % change in Td, VD-nt and VEGFmax resulted in +50%, +25% and +5% increase in peak pO2. In contrast, Td was the most influential on the time to peak oxygenation with VD-nt and VEGFmax playing marginal roles. A +20% change in Td, VD-nt and VEGFmax increased the time to peak pO2 by +50%, +5% and +0%. A −20% change in the above parameters resulted in comparable decreases in the peak and time to peak pO2. Model application to the PET data was able to demonstrate the voxel-specific changes in hypoxia of the imaged tumor. Conclusion: Tumor-specific doubling time and vessel density are important parameters to be considered when evaluating hypoxia transients. While the current model simulates the oxygen dynamics of an untreated tumor, incorporation of therapeutic effects can make the model a potent tool for analyzing anti-angiogenic therapies.
Maternal-fetal conflict: an ethical analysis.

C oncerns for the health of a fetus that is destined to become an infant are a central focus of the care and treatment of pregnant women. Recently, these concerns have begun to overpower respect for the rights of pregnant women as obstetrical patients. Physicians have recommended and sought to impose a variety of medical or surgical interventions on pregnant women, sometimes for the women's own benefit and almost always for the sake of the fetus. The most recent trend is a growing movement joined by physicians, prosecutors, and legislators to coerce, detain, or incarcerate women who use drugs or abuse alcohol during pregnancy. This practice of treating adult pregnant women differently from other competent adults cannot be ethically justified. It is useful to begin an ethical analysis by identifying points on which all can agree. There are at least two propositions on which universal agreement is likely to be forthcoming. The first is that it is better for babies to be born healthy rather than unhealthy. Put another way, it is desirable for infants to be free from preventable diseases and developmental disabilities. This proposition is not meant to have any implications for those infants or children who are born with birth anomalies or diseases. It is perfectly consistent to hold that it is a better state of affairs for infants to be born healthy and sound than otherwise and at the same time to maintain that infants born with disabilities deserve the same treatment and respect as healthy and able-bodied individuals. The second proposition is that pregnant women have a moral obligation to act in ways likely to result in the birth of a sound, healthy infant. This second proposition follows from the first. If it is better for infants to be born healthy than unhealthy, and if behavior on the part of pregnant women can help to ensure that desirable outcome, then they have a moral obligation to act in ways most likely to bring about the desirable outcome. What follows from the moral obligation of pregnant women toward their future children? Like other moral obligations, it is contingent on a reasonable ability to comply. Before people can be assigned moral obligations to act or refrain from acting in certain ways, they must be physically and psychologically capable of acting in those ways. What constitutes a "reasonable ability to comply" is often uncertain and open to dispute. In the case of pregnant women, a number of different constraints might limit their ability to comply © 1990 by The Jacobs Institute of Women's Health 1049-3867/90/$3.50
Pacing at a Very Short Pulse Width

Abstract From March, 1973, to June, 1975, 112 variable pulse width pulse generators (Medtronic 5931, 5961) were implanted in 109 patients. The devices were used routinely with both acute (59) and chronic (53) pacing electrodes. No special technique to obtain an unusually low pacing threshold was used or necessary. A chronic pulse width of 0.29 ± 0.07 msec was set, and no patient had failure to pace in the absence of severe electrode malfunction. Follow-up of between two and four and a half years is available on 93% (104) of the series, 8 patients having been lost to follow-up. A total of 38 pulse generators are out of service because of death unrelated to pacing (11), death related to pacing (3), electrode malfunction (16), pulse generator failure (5), or miscellaneous causes (3). Actuarial analysis for pulse generator failure shows a 92% survival at three years and 85% at four years with a total of 66 pulse generators remaining in service. Similar analysis shows a consistent incidence of 6% per year for both electrode malfunction from all causes and patient death from all causes. Clinical pacing at a pulse width shorter than that commonly used is safe and practical and results in a significant increase in the longevity of mercury cell-powered pacemakers. With the high cost and limited real-time longevity experience with pacemakers powered by lithium cells, a standard mercury-zinc pulse generator remains an acceptable alternative in selected patients.
Intercropping Maize with Climbing Beans, Cowpeas and Velvet Beans

When one of the crops is a legume, intercropping has potential to reduce fertilizer nitrogen (N) needs and increase food quality. Total dry matter (DM) and grain yields of different plant populations of intercropped maize (Zea mays L.) and climbing beans (Phaseolus vulgaris L.), cowpeas (Vigna unguiculata [L.] Walp.), or velvet beans (Mucuna pruriens [L.] DC. var utilis [Wight] Bruck.) were compared in two experiments. Maize populations were 40,400 and 50,500 plants ha−1 in combination with climbing bean populations of 0, 20,200, 40,400 and 80,800 plants ha−1 in Experiment 1. In the second experiment, climbing beans, cowpeas and velvet beans at 215,200 plants ha−1 were intercropped with maize at 64,600 plants ha−1. Climbing beans contributed up to 5% to total DM yields in the first experiment. In the second experiment legume contributions to total DM were 20% for climbing beans, 12% for cowpeas and 8% for velvet beans. Increasing populations of maize and climbing beans increased grain and DM yields. Dry matter yield of maize was lowered by intercropping. However, DM yields of the intercrop were not different to maize sole cropped. Maize/cowpeas produced more total DM than maize/climbing beans. Cowpeas increased the total yield of crude protein by over 15% without lowering total DM yield of the intercrop compared to maize alone and are promising as a legume for intercropping with maize. Climbing beans show little promise as a possible legume for intercropping with maize.
Obligations of a Clinical Supervisor

This article offers the author's definition of his responsibilities as a clinical supervisor. Treatment professionals promoted into a supervisory capacity do not always realize their new obligations, thereby leaving some responsibilities uncared for while they remain only client-oriented and not organization-oriented.
Reversion der Saccharide und Transglycosidierung im sauren Milieu. II. Zur Transglycosidierung im sauren Milieu

1. Es werden die Vorgange der enzymatischen Synthese und der enzymatischen Transglycosidierung bei Sacchariden an verschiedenen Modellen systematisch untersucht und die Angaben der Literatur im wesentlichen bestatigt. 2. Bei der Saureeinwirkung auf verschiedene Disaccharide (Maltose, Cellobiose, Lactose) wird chromatographisch festgestellt, das vor dem Sichtbarwerden von hohermolekularen Reversionsprodukten Oligosaccharide anderer Bildungsweise auftreten. 3. Durch zeitlich abgestufte Hydrolyse gelingt es, die Produkte der sauren Transglycosidierung von denen der Reversion abzugrenzen. 4. Es wird gezeigt, das die bei der sauren Ubertragung gebildeten Produkte wahrscheinlich im weiteren Verlauf der Umsetzungen um- oder abgebaut werden. 5. An Hand der vergleichenden Auswertung der Ergebnisse uber die enzymatische und die saure Transglycosidierung wird gefolgert, das sich im sauren Milieu ahnliche Prozesse abspielen wie bei der enzymatischen Ubertragung von Sacchariden von einem Donator- auf ein Acceptor-Saccharid.
Environmental effects on resistance gene expression in milk stage popcorn kernels and associations with mycotoxin production

Like other forms of maize, popcorn is subject to increased levels of contamination by a variety of different mycotoxins under stress conditions, although levels generally are less than dent maize under comparable stress. Gene array analysis was used to determine expression differences of disease resistance-associated genes in milk stage kernels from commercial popcorn fields over 3 years. Relatively lower expression of resistance gene types was noted in years with higher temperatures and lower rainfall, which was consistent with prior results for many previously identified resistance response-associated genes. The lower rates of expression occurred for genes such as chitinases, protease inhibitors, and peroxidases; enzymes involved in the synthesis of cell wall barriers and secondary metabolites; and regulatory proteins. However, expression of several specific resistance genes previously associated with mycotoxins, such as aflatoxin in dent maize, was not affected. Insect damage altered the spectrum of resistance gene expression differences compared to undamaged ears. Correlation analyses showed expression differences of some previously reported resistance genes that were highly associated with mycotoxin levels and included glucanases, protease inhibitors, peroxidases, and thionins.
Genomic organization of the ribosomal DNA of sorghum and its close relatives

The structure and organization of the ribosomal DNA (rDNA) of sorghum (Sorghum bicolor) and several closely related grasses were determined by gel blot hybridization to cloned maize rDNA. Monocots of the genus Sorghum (sorghum, shattercane, Sudangrass, and Johnsongrass) and the genus Saccharum (sugarcane species) were observed to organize their rDNA as direct tandem repeats of several thousand rDNA monomer units. For the eight restriction enzymes and 14 cleavage sites examined, no variations were seen within all of the S. bicolor races and other Sorghum species investigated. Sorghum, maize, and sugarcane were observed to have very similar rDNA monomer sizes and restriction maps, befitting their close common ancestry. The restriction site variability seen between these three genera demonstrated that sorghum and sugarcane are more closely related to each other than either is to maize. Variation in rDNA monomer lengths were observed frequently within the Sorghum genus. These size variations were localized to the intergenic spacer region of the rDNA monomer. Unlike many maize inbreds, all inbred Sorghum diploids were found to contain only one rDNA monomer size in an individual plant. These results are discussed in light of the comparative timing, rates, and modes of evolutionary events in Sorghum and other grasses. Spacer size variation was found to provide a highly sensitive assay for the genetic contribution of different S. bicolor races and other Sorghum species to a Sorghum population.
CONTROVERSIES IN PEDIATRIC AMBULATORY ANESTHESIA

The aim of this article is to highlight some of the contentious issues facing the anesthesiologist while dealing with children. In each instance the authors outline the controversy, review the literature in this regard, and conclude with suggestions on management. Because these are controversial not all will agree with the authors' viewpoint or suggestions; however, the practitioner needs to keep in mind that regardless of the decision he or she may make, it should be based on science and stand up to discussion. The authors also encourage anesthesiologists to discuss these issues and come up with guidelines best suited to their practice.
Regulation of insulin-like growth factor-binding protein 1 by hypoxia and 3',5'-cyclic adenosine monophosphate is additive in HepG2 cells

Insulin-like growth factor-binding protein 1 (IGFBP-1) is important in regulating minute-to-minute IGF bioavailability in the circulation and is primarily an inhibitor of IGF action systemically and in most cellular systems. Understanding regulation of IGFBP-1 is, thus, important in understanding regulation of IGF actions. The IGFBP-1 promoter contains a cAMP response element, and cAMP stimulates IGFBP-1 gene expression at the transcriptional level. Recently, we have found three consensus sequences for the hypoxia response element in intron 1 of the IGFBP-1 gene. Herein, we have investigated the effects of hypoxia and a cAMP analog, 8-bromoadenosine-3′,5′-cyclic monophosphate (8-Br-cAMP), on IGFBP-1 expression in HepG2 cells, a model system for IGFBP-1 gene regulation. HepG2 cells were exposed to normoxia (20% pO2) or hypoxia (2% pO2) for 24 h in the absence or presence of 8-Br-cAMP (0.1, 0.5, and 1 mm). Western ligand blotting revealed IGFBP-1 as the predominant IGFBP in HepG2-conditioned media, which in...
Effect of an image-sharing network on CT utilization for transferred trauma patients: a 5-year experience at a level I trauma center.

Purpose The aim of this study was to evaluate the influence of an image-sharing network established between referring hospitals and a level I trauma center on CT utilization at the trauma center. Methods This retrospective study was approved by the local institutional review board. The requirement for informed consent was waived. Harborview Medical Center's trauma registry was linked to billing department data, and detailed information on all resources utilized during each patient's hospitalization was obtained. Negative binomial regression was used to evaluate body region–specific CT utilization between direct-admit and transfer patients after adjustment for potential confounding variables. Special attention was paid to 2005 as the year internet-based image sharing between Harborview Medical Center and referring hospitals was established. Results A total of 81,159 trauma patients were admitted to Harborview Medical Center (44% transfers) during the study period. The utilization of head CT slightly increased from 1996 to 2005, with no significant difference between direct-admit and transfer patients. Between 2005 and 2010, utilization remained relatively unchanged; however, significantly higher utilization rates were observed for direct-admit patients. A relatively similar pattern was observed for pelvic CT; however, between 2005 and 2010, CT use was greater for direct-admit compared with transfer patients. Abdominal and thoracic CT was relatively unchanged between 2005 and 2010. However, both studies had significantly higher utilization rates for direct-admit patients. Conclusions The utilization rates of CT of different body regions have been higher for direct-admit trauma patients compared with transfer patients since 2005; however, decreasing utilization trends have been observed in recent years.
Finite horizon Riemann structures and ergodicity

In this paper we show that any surface in $\mathbb{R}^3$ can be modified by gluing on small ‘focusing caps’ so that its geodesic flow becomes ergodic. A new concept, finite horizon cap geometry, is what makes the construction work.
Growth of carbon-based nanostructures

Carbon nanostructures such as carbon nanotubes (CNTs) and graphene are being applied to a wide variety of sensor applications. Both CNTs and graphene can be grown by chemical vapor deposition (CVD) from hydrocarbons using catalysts. Both materials require metallic catalysts. CNTs require small particles while graphene requires continuous films. Both materials can be grown by the thermal decomposition of SiC. Under the proper conditions either vertically aligned CNT arrays or planar graphene can be grown. Carbon source molecular beam epitaxy (CMBE) is also under development for growth of graphene. Like SiC decomposition, CMBE is catalyst free but it is not restricted to SiC substrates.
Martian climate: an empirical test of possible gross variations.

There appears to be evidence for a cyclic behavior of the Martian climate in which the surface pressure periodically reaches values compatible with the flow of water in equatorial regions on the planet. A relatively simple test of such hypotheses is pointed out. The premise on which cyclic models are based is that a substantial reservoir of volatils exist in frozen form at one or both poles. The proposed test involves a determination of the relative abundances of neon and argon isotopes. The required measurements may be made after the soft landing next February of Soviet spacecraft presently en route to the planet.
Feuerbach and gender: the logic of complementarity

Ludwig Feuerbach's work is often too easily dovetailed with the works of Hegel and Marx and therefore read teleologically as an intermediary step between the two “major” figures. By re-interpreting Feuerbach more as a system critic than as a system builder, this article attempts to elucidate his relationships to the other two. It will also point up the gendered articulation of his critiques of religion and philosophy. The article will show how Feuerbach's use of gender, though remaining fixed within a predictably hierarchical binary, is more than simply symptomatic of its context and offers significant resources for critical re-readings of nineteenth-century German philosophy.
Spinoza's problem of “other minds”

Spinoza produced one of the great metaphysical systems of Western Philosophy. In this paper, I deal with one of the most obscure problems in that system, viz., the problem of "other minds". A treatment of this problem sheds light on Spinoza's entire metaphysical system. However, this is not the problem of other minds as usually treated by philosophers. It is not the problem are there other minds more or less like my own, and not just robot bodies out there? Rather, it is a problem peculiar to Spinoza's system, arising from his view that in addition to the known attributes of Extension and Thought, there are infinitely many unknown attributes of God, all perfectly parallel, or isomorphic, to each other. Spinoza's problem may be stated as follows: are there other kinds of minds which, though isomorphic to my own, perceive things under the unknown attributes; and are such minds compatible with the isomor phism between the attributes? In other words, are these other minds compatible with the perfect parallelism? This question is closely allied with the question whether the attribute of Thought has a special place in Spinoza's system. Given the perfect parallelism of the attributes and the Spinozistic proposition that each attribute expresses the essence of God, it seems that Thought should have no special place among the attributes. Yet, in dealing with the problem of other minds, it would appear that Spinoza does give Thought a special place. In this paper, I shall present various alternative solutions to Spinoza's problem. In particular, I shall argue against Curley's solution, which weakens the parallelism of God's attributes while preserving God's perfect omniscience. Mainly, I shall develop my own solution to Spinoza's problem, with two variations. The first variation preserves both perfect parallelism and perfect omniscience, but at the expense of a problematic infinite regress. The second variation weakens omniscience while preserving perfect parallelism. Finally, I shall present an extra textual solution.
Risk factors for Burkholderia cepacia complex colonization and infection among patients with cystic fibrosis.

Abstract Objectives: To determine risk factors for acquiring Burkholderia cepacia complex among patients with cystic fibrosis (CF). Study design: A case-control study was conducted with active surveillance for B cepacia complex colonization/infection among patients at 21 CF centers from April 1986 to March 1989 (study period). A case-patient was defined as any CF patient with B cepacia complex colonization for the first time during the study period. Control patients were patients with CF not B cepacia complex colonized during the study period. For each patient, a questionnaire was completed semiannually. Results: In multivariate analyses, hospitalization for pulmonary exacerbations, living with a B cepacia complex-positive person, attending a CF summer camp, and direct contact with a B cepacia complex-colonized CF person outside of camp and home were associated with B cepacia complex acquisition. Receiving antimicrobial aerosol therapy or cleaning and drying a home-used nebulizer between uses were associated with a decrease in B cepacia complex acquisition. Conclusions: Numerous factors inside and outside the health care setting are associated with person-to-person transmission of B cepacia complex among patients with CF. Prevention programs should reduce direct or indirect contact between noncolonized and B cepacia complex-colonized/infected patients with CF. (J Pediatr 2002;141:512-7)
Abstract 4560: A new IGF-1-integrated Child-Pugh score to risk-stratify patients with hepatocellular carcinoma

Proceedings: AACR 103rd Annual Meeting 2012‐‐ Mar 31‐Apr 4, 2012; Chicago, IL Purpose The Child-Pugh (CP) system is the major tool for assessing the underlying liver condition and guiding therapy decisions in hepatocellular carcinoma (HCC) patients. It is itself relatively quantitative and uses five empirically selected variables, including hepatic encephalopathy and ascites, which are clinically difficult to grade and may vary in severity according to medical management of patients. Insulin-like growth factor-1 (IGF-1) is produced predominantly in the liver, and hence reflects its synthetic function. Our study objective was to build a new CP score by integrating plasma IGF-1 level into the CP parameters to refine its prognostic stratification ability. Patients and Methods We prospectively collected plasma samples and clinical data from 310 individuals with HCC. IGF-1 levels were measured by ELISA and recursive partitioning was used to identify optimal cut points and IGF-1 ranges, using training and validation sets, and established the cut-off values of IGF-1 arranged so as to define the three distinct groups of IGF-1 with increasing liver function severity; A=1, B=2, and C=3. We then constructed the new score by replacing points from ascites and encephalopathy with plasma IGF-1 points; the new score points = 4-11. Finally, we performed log rank test for both systems, and also compared their prognostic abilities using concordance index (c-index). Results Compared with CP system, the new system (c -index = 0.608) improves the capacity in predicting OS and refined the stratification of all classes of the original CP (c-index = 0.573), (p value = 0.0029). Conclusion Replacing ascites and encephalopathy by plasma IGF-1 significantly improved prediction of OS and prognostic stratification of the conventional CP system. After external validation, the new scoring system may become the standard of care in guiding therapy decisions and stratifying HCC patients in clinical trials. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4560. doi:1538-7445.AM2012-4560
STUDENT PERSPECTIVES ON SUCCESS IN HIGH SCHOOL CHEMISTRY

The purpose of this study was to hear the voices of college-bound high school students concerning meaning and action in cultural context. Students explain what it means to understand and to succeed in introductory chemistry. The method was ethnographic and interpretive as the researcher took on the role of participant observer in introductory chemistry classes in two Midwestern public high schools during one school year. A focus group of students from each school and the two teachers were interviewed and participated in informal conversations. Field notes and interviews were considered primary data sources. Audiotape transcriptions and written artifacts served as secondary sources. Students explained understanding in at least two ways, one practical and task oriented, while the other definition was theoretical and epistemological. Success associated with the latter understanding was elusive, yet considered more meaningful. © 1999 John Wiley & Sons, Inc. J Res Sci Teach 36: 221–237, 1999
Novel cleaved edge overgrowth structures for tunneling into one- and two-dimensional electron systems

Abstract We report the fabrication of novel electron in-plane tunneling systems in GaAs Al x Ga 1−x As using the technique of cleaved edge overgrowth, and report results of tunneling measurements into both one- and two-dimensional (1D and 2D) systems. Our devices demonstrate tunneling through an abrupt molecular beam epitaxially defined barrier where the shape of the barrier potential is exactly known. We study three different in-plane tunneling geometries, namely 2D-1D-2D, 2D-2D and 2D–3D, and report current vs voltage characteristics for all three geometries.
Laterality, somatotopy and reproducibility of the basal ganglia and motor cortex during motor tasks.

We investigated the basal ganglia, motor cortex area 4, and supplementary motor area (SMA) using functional magnetic resonance imaging (fMRI) and five motor tasks: switching between finger and toe movements, writing, finger tapping, pronation/supination, and saccadic eye movements. We found reliable activation in the caudate nucleus and putamen in single subjects without the need for inter-subject averaging. Percent signal changes in basal ganglia were smaller by a factor of three than those in SMA or motor cortex (1% vs. 2.5–3%). There was a definite foot-dorsal, hand-ventral basal ganglia somatotopy, similar to prior data from primates. Saccadic eye movements activated the caudate nucleus significantly more than the other tasks did. Unilateral movements produced bilateral activation in the striatum even when motor cortex activation was unilateral. Surprisingly, bilateral performance of the tasks led, on average, to consistently smaller basal ganglia activation than did unilateral performance (P<0.001), suggesting less inhibition of contralateral movements during bilateral tasks. Moreover, there was a striking dominance pattern in basal ganglia motor activation: the left basal ganglia were more active than the right for right handers, regardless of the hand used. This lateralization appears much stronger than that previously reported for motor cortex. Comparisons of inter-subject and intra-subject reproducibility indicated a much larger variability in basal ganglia and SMA compared to motor cortex, in spite of similar percent signal changes in the latter two structures.
A knowledge-based approach to improve neural network control design

Control engineers have been investigating and developing different on-line adaptation schemes to fine-tune performance of controllers after off-line design. Artificial neural network technology has shown satisfactory results for many control applications. However, certain types of nonlinear problems are difficult for the neural controller to learn by conventional on-line adaptation schemes, while the nonlinear system can be effectively controlled by incorporating heuristics knowledge. This paper presents an effective approach to incorporate heuristics control knowledge into a neural controller by off-line pre-training, then fine-tune the neural controller performance further by on-line adaptation. Experimental results on a servomotor system with significant nonlinear friction characteristics are used to demonstrate the effectiveness of the design approach.
Natural variation in life history and aging phenotypes is associated with mitochondrial DNA deletion frequency in Caenorhabditis briggsae

Mutations that impair mitochondrial functioning are associated with a variety of metabolic and age-related disorders. A barrier to rigorous tests of the role of mitochondrial dysfunction in aging processes has been the lack of model systems with relevant, naturally occurring mitochondrial genetic variation. Toward the goal of developing such a model system, we studied natural variation in life history, metabolic, and aging phenotypes as it relates to levels of a naturally-occurring heteroplasmic mitochondrial ND5 deletion recently discovered to segregate among wild populations of the soil nematode, Caenorhabditis briggsae. The normal product of ND5 is a central component of the mitochondrial electron transport chain and integral to cellular energy metabolism. We quantified significant variation among C. briggsae isolates for all phenotypes measured, only some of which was statistically associated with isolate-specific ND5 deletion frequency. We found that fecundity-related traits and pharyngeal pumping rate were strongly inversely related to ND5 deletion level and that C. briggsae isolates with high ND5 deletion levels experienced a tradeoff between early fecundity and lifespan. Conversely, oxidative stress resistance was only weakly associated with ND5 deletion level while ATP content was unrelated to deletion level. Finally, mean levels of reactive oxygen species measured in vivo showed a significant non-linear relationship with ND5 deletion level, a pattern that may be driven by among-isolate variation in antioxidant or other compensatory mechanisms. Our findings suggest that the ND5 deletion may adversely affect fitness and mitochondrial functioning while promoting aging in natural populations, and help to further establish this species as a useful model for explicit tests of hypotheses in aging biology and mitochondrial genetics.
Flutter suppression of a plate-like wing via parametric excitation

The present work is motivated by the well known stabilizing effect of parametric excitation of some dynamical systems such as the inverted pendulum. The possibility of suppressing wing flutter via parametric excitation along the plane of highest rigidity in the neighborhood of combination resonance is explored. The nonlinear equations of motion in the presence of incompressible fluid flow are derived using Hamilton's principle and Theodorsen's theory for modeling aerodynamic forces. In the presence of air flow, the bending and torsion modes possess nearly the same frequency. Under parametric excitation and in the absence of air flow, each mode oscillates at its own natural frequency. In the neighborhood of combination resonance, the nonlinear response is determined using the multiple scales method at the critical flutter speed and at slightly higher airflow speed. The domains of attraction and bifurcation diagrams are obtained to reveal the conditions under which the parametric excitation can provide stabilizing effect. The basins of attraction for different values of excitation amplitude reveal the stabilizing effect that takes place above a critical excitation level. Below that level, the response experiences limit cycle oscillations, cascade of period doubling, and chaos. For flow speed slightly higher than the critical flutter speed, the response experiences a train of spikes, known as ‘firing,’ a term that is borrowed from neuroscience, followed by ‘refractory’ or recovery effect, up to an excitation level above which the wing is stabilized. The results of the multiple scales method are verified using numerical simulation of the original nonlinear differential equations.
Maximally Reliable Composites for Unidimensional Measures

A general approach to obtaining weights and reliability coefficients of maximally reliable composites is offered for a variety of test theoretic models which assume a single common underlying dimension. The reliability maximizing weights are related to the theoretically specified true score scaling weights to show there is a constant relationship between them that is invariant under separate linear transformations on each variable in the system. Furthermore, an argument is made that test theoretic relations should be derived for the most general model available and not for unnecessarily constrained models.
Adult Children of Divorce: Awareness and Intervention

Parental midlife divorce impacts children who are adults at the time of the separation event. This article examines the family life cycle and stages as well as the transitions that occur when parents divorce at midlife. Specifically, the divorce impacts on the adult children are examined in relation to their unique life stage. Therapeutic practice implications and theories will also be explored in relation to assisting adult children of divorce reconcile the divorce experience of their parents.
A Practitioner's Guide to Computation and Interpretation of Reliability Indices for Mastery Tests

From the perspective of teachers and test makers at the district or state level, current methods for obtaining reliability indices for mastery tests like the agreement coefficient and kappa coefficient are quite laborious. For example, some methods require two test administrations, whereas single administration approaches involve complex statistical procedures and require access to appropriate computer software. The present paper offers practitioners tables from which agreement and kappa coefficients can be read directly. Furthermore, because these indices differ from traditional reliability coefficients, the issue of what constitutes acceptable values of agreement and kappa coefficients is also addressed. As Berk (1980, 1984) has noted in reviewing the literature on criterionreferenced test reliability, methods for computing and interpreting reliability indices for mastery tests can be complex from a practitioner's point of view. For example, the method proposed by Swaminathan, Hambleton, and Algina (1974) requires two administrations of the same or parallel tests. Given examinees' mastery-nonmastery classifications on both administrations, two reliability indices that have been recommended are (a) the agreement coefficient or (b) the kappa coefficient. These two coefficients measure the consistency of masterynonmastery classifications across two test administrations, and both require somewhat different interpretations than traditional reliability coefficients, which are essentially correlations of test scores on two administrations. The agreement coefficient is simply the porportion of examinees consistently classified (as masters or as nonmasters) on both administrations. When the
CaMg ratio classification of main limestones (Mississippian) in South Wales, U.K.

Abstract The highly dolomitized Main Limestones of approximately Mississippian age, which crop out in South Wales, are classified according to their Ca Mg ratio values. The results based upon the Ca Mg ratio determination of these rocks permitted their classification into six major categories, namely: (1) limestone; (2) slightly dolomitized limestone; (3) dolomitic limestone; (4) calcitic dolostone; (5) dolostone proper; and (6) magnesian dolostone. It is concluded that dolostone proper and calcitic dolostone tend to dominate in the Main Limestone rocks of South Wales.
The galvanic corrosion of SiC monofilament/ZE41 Mg metal-matrix composite in 0.5 M NaNO3

Abstract The effect of composite constituents and dissolved O 2 on the corrosion behavior of a SiC monofilament/ZE41 Mg metal-matrix composite (MMC) exposed to 0.5 M NaNO 3 was studied. The SiC monofilament (MF) (which consisted of a carbon core, a layer of chemical-vapor deposited SiC, and an outer carbon-rich surface) supported cathodic current densities comparable to that of graphite. The corrosion of pure Mg and a ZE41A Mg alloy was not affected by dissolved O 2 . Corrosion rates of the MMC, however, increased with dissolved O 2 since the MFs were effective O 2 -reduction sites, which enchanced galvanic corrosion.
Political opposition in post-Confucian society

Traditional Government in East Asia The Transformation of the Traditional Societies Politics and Opposition in Taiwan Politics and Opposition in South Korea Politics and Opposition in South Vietnam Politics and Opposition in China Politics and Opposition in North Korea Politics and Opposition in Vietnam Politics and Opposition in Japan Conclusions Bibliography Index
The energetics and kinetics of uranyl reduction on pyrite, hematite, and magnetite surfaces: A powder microelectrode study

Abstract There are many studies describing the influence of parameters such as pH, pCO 2 , and complexing ligands on the sorption of the aqueous uranyl species onto mineral surfaces. However, few of these studies describe the reduction reaction mechanisms and the factors that influence the rate of reduction, despite the fact that the oxidation state of uranium is the most important factor controlling the mobility of uranium. In this study, the energetics and kinetics of the U(VI) reduction half-reaction on pyrite, hematite, and magnetite were investigated by electrochemical methods using a powder microelectrode (PME) as the working electrode. Anodic and cathodic peaks corresponding to the 1 e - redox couple, U(VI)/U(V), were identified in cyclic voltammograms of pyrite, hematite, and magnetite at pH 4.5. A second oxidation peak, corresponding to the oxidation of U(IV), was identified and provides evidence for the formation of reduced uranium phase(s) on the mineral surfaces. In addition, uranium-containing precipitates were identified on pyrite surfaces after polarization in a PME. This study identifies the disproportionation of U(V) species on the surface as a possible rate-limiting step in the two-step U(VI) reduction mechanism: (1) charge transfer to form U(V) followed by, (2) a disproportionation reaction that forms U(IV) and U(VI). The Tafel slope ( i.e ., the derivative of the electrode potential with respect to log [current]) was used to evaluate electrochemical mechanisms. High Tafel slopes (>220 mV/(log unit of current) on all minerals evaluated) suggest that uranyl reduction is mediated by insulating (hydr)oxide layers that are present on the semiconducting mineral surfaces. The onset potential for uranyl reduction was determined for pyrite (>+0.1 V vs . Ag/AgCl), and hematite and magnetite (between−0.02 and−0.1 V vs. Ag/AgCl). The onset potential values establish a baseline kinetic parameter that can be used to evaluate how solution conditions ( e.g. , dissolved reductants, complexing ligands, and polarizing ions) affect the kinetics of uranyl reduction. The results of this study demonstrate the potential for using PMEs to evaluate redox potentials and mechanisms for U(VI) reduction by Fe-oxides and sulfides under more complex solution conditions as well as other environmentally-relevant mineral-analyte systems. However, it should be noted that the determination of redox kinetics using Butler–Volmer theory has limitations when applied to semiconductor mineral electrodes. Charge depletion in semiconductor surface states can affect the kinetic values obtained for redox reactions on the surface. These limitations and a discussion of the flat band potential are considered in the interpretation of U redox kinetics in this study.
Effects of synthetic TRH on in vitro and in vivo prolactin release in the rat.

The effects of synthetic thyrotropinreleasing hormone (TRH) were measured on release of prolactin by normal rat pituitary and pituitary tumor tissue in vitro, and in vivo on pituitary and serum prolactin concentrations in intact and thyro—parathyroidectomized male rats. TRH in doses of 3 and 30 ng was incorporated into medium 199 containing a half anterior pituitary from normal male rats. No significant effect was observed on prolactin release by the end of 4, 8 or 12 hr of incubation when compared with control pituitary halves. Similar doses of TRH were incubated with rat pituitary tumor (MtT.WlS) tissue for the same periods, and again no effect was observed on prolactin release. A single iv injection of 5 or 7.5 μg of TRH was given to male rats and blood samples were collected IS and 30 min later. No change was observed in serum prolactin levels. When 50 μg TRH was injected iv daily for 6 days into intact male rats, there was a significant increase in pituitary prolactin concentration and a small but in...
Judging the predictors of one's own mood: Accuracy and the use of shared theories

Abstract The origins of judgments about the predictors of one's own mood was investigated. Fifty subjects filled out questionnaires about their mood and several predictor variables (e.g., the weather and the amount of sleep they received) every day for 5 weeks. The actual correlations between the predictor variables and mood were computed for each subject, and compared with the subjects' estimates of these correlations. In addition, a group of “observer subjects,” strangers to the subjects who were given only brief descriptions of the predictor variables, estimated how these variables were related to mood. Although a moderate degree of accuracy was found between subjects' estimates and the actual correlations, a substantial number of errors were made. Most importantly, the subjects' estimates were no more accurate than were the predictions made by the observer subjects. Rather than basing their judgments about mood on the data available to them, subjects seem to have relied on theories about mood, theories that were shared by the observers. In addition, two manipulations were included that attempted to increase the accuracy of subjects' estimates by focusing their attention on the relationship between mood and one of the predictor variables (amount of sleep). These attempts were for the most part unsuccessful. Even when judging a response as important as their own mood, and even when prodded to look more closely at the data, subjects clung tenaciously to their theories, theories that were often wrong.
The survey questionnaire

In this chapter, we describe development of the online survey questionnaire, including organization, layout, formatting, and response formats.