cssi/SciSciGPT-SciSciNet huggingface dataset:
ECOLOGICAL ASPECTS OF ICEBERG TRANSPORT FROM ANTARCTIC WATERS

Final engineering decisions on transport, insulation, and melting technology will have a profound influence on ecological consideration. From Antarctic experience temporary lakes containing algae often form on the surface of glaciers causing a decrease in albedo. This may be expected to accelerate surface melt loss during transport unless the iceberg's exposed surface is protected as well as its sea water contact. The presence of seals, penguins, and Skua gulls on the iceberg might require discouragement during transport to reduce fecal and salt gland contamination of the ice. As the ice is transported to lower latitudes, warm surface waters will tend to move towards the ice, cool and rise, due to a decrease in salinity to form a surface plume. As shallow water is approached, or where the iceberg is eventually grounded, cold water pollution could cause mortality among littoral fish and benthos in the vicinity of the berg. Reduced salinity might also cause secondary problems of osmoregulation among the fauna if melt water loss is extensive. Localized climatic changes with cooling and possible fog should be anticipated. Meromictic (non-mixing) conditions may result and might be encouraged from cold water storage on shore. On the basis of Antarctic experience eutrophic conditions in melt water could develop despite the low temperatures if control of nutrient inputs is neglected. Although environmental problems are certain to arise from an operation of this magnitude, combining engineering and ecological design can provide for their solution.
Can stock market liquidity and volatility predict business cycles

The purpose of this paper is to predict real gross domestic product (GDP) growth and business cycles by using information from both liquidity and volatility measures.,The paper estimates liquidity and volatility measures from over 5,000 NYSE rms and extracts a common factor, which the paper calls uncertainty. In-sample and out-of-sample forecasting tests are used to determine the ability of the uncertainty factor to predict growth in real GDP, industrial production, consumer price index, real consumption and changes in real investment.,The paper finds that on average, positive shocks to the uncertainty factor occur in the quarters preceding and at the beginning of a recession. During the quarters toward the end of recessions, there are negative shocks to uncertainty on average.,Previous research has explored using either liquidity or volatility to forecast economic activity. The paper bridges the two branches of research and finds a link to real GDP growth and business cycles.
Gender, Religion, and the Work of Homeschooling

In this chapter, I examine the ways in which the claim to subaltern status has led to a partial withdrawal from state-run institutions and to a practice of schooling that is meant to equip the children of authoritarian populist conservative religious parents both with an armor to defend what these groups believe is their threatened culture and with a set of skills and values that will change the world so that it reflects the conservative religious commitments that are so central to their lives. I focus on the ways in which new technologies such as the Internet have become essential resources in what authoritarian populists see as a counter-hegemonic struggle against secular humanism and a world that no longer “listens to God’s word”. In fact, it is becoming increasingly clear that new technologies such as the Internet actually enable the formation and growth of such religious movements and enhance their ability to challenge secularity. Much of my discussion centers around the place of gender in these movements since conservative women are key actors here and have multiple identities within them—simultaneously able to claim subaltern status based on the history of dominant gender regimes and having dominant status given their positioning in relationship to other oppressed groups.
Abstract 1849: Gender Differences in Left Ventricular Ejection Fraction Assessment between Transthoracic Echocardiography and Gated Single Photon Emission Computed Tomography: Data from 2704 Patients

BACKGROUND: Left ventricular ejection fraction (LV EF) has been used historically as a prognostic tool in patients with various ischemic and non-ischemic cardiomyopathies. More recently, its use has been expanded to determine eligibility for antitachycardia device implantation. Testing methods for assessing LV EF, however, have not been uniform. We have previously reported a general bias of approximately +9%-points for gated single photon emission computed tomography (SPECT) assessment of LV EF when compared to assessment by transthoracic echocardiography (TTE). We sought to identify the existence of a gender-related pattern to this bias. METHODS: We identified 2704 consecutive patients from October 2004 to December 2005 who underwent both TTE and gated SPECT within 1 month’s time at our institution. Reported LV EF by gated SPECT was compared to that by TTE within gender groups using Spearman rank correlation analysis for non-parametric variables and the Bland-Altman method for assessing bias between measurement methods. RESULTS: Correlation analysis among males yielded a correlation coefficient of 0.66 (95% confidence interval (CI) 0.63–0.69; p CONCLUSIONS: In women, LV EF as measured by gated SPECT is generally 10% higher than that measured by TTE; this disparity decreases among men. Further studies are necessary to clarify the clinical impact of this difference when determining device eligibility.
Can Guided Play and Storybook Reading Promote Children’s Drawing Development?:

Children’s drawings are implicated in their emotional, cognitive, artistic, and semiotic development, raising the question of how early educators may best facilitate drawing development. This study...
THE COGNITIVE SIDE OF VISUAL SEARCH IN RADIOLOGY

Search is composed of survey and examination fixations which, when coupled, form basic perceptual-cognitive decision units. These basic perceptual-cognitive units feed the interpretative decision-making process. Search stages depend on the effectiveness of perceptual-cognitive units. The survey or screening aspect of the perceptual-cognitive unit contributes mainly to global and discovery search stages. The examination aspect of the perceptual-cognitive unit contributes mainly to the reflective search stage. Contrast affects the efficiency of the perceptual-cognitive unit by decreasing surveying and screening and shifting the analysis to the examination side of visual search.
The Neglected Fragile X Mutations: FRAXE and FRAXF

The first triplet-repeat mutation to be reported was the large d(CGG) repeat expansion found in individuals with Fragile X syndrome (Verkerk et al. 1991). Significant attention has been paid to this common disease, the dynamics of its d(CGG) repeat, and the function of its associated gene, FMR1 (Bagni and Greenough 2005). However, two other folate-sensitive fragile sites in the region have received much less attention since they were found to be distinct from the sequence affected in Fragile X syndrome. These sites, FRAXE and FRAXF are reviewed here. FRAXE expansion results in a mild learning deficit, can lead to more severe mental retardation, and has been associated with other mental disorders. FRAXF is apparently benign when expanded despite affecting at least one nearby gene. Interestingly, each of the fragile site loci contains a d(CGG) or d(CCG) repeat that is expressed in the 5′ untranslated portion of a neuronally expressed gene. Each expanded repeat sequence exhibits similar properties of instability, methylation and extinction of gene expression resulting in a loss of function of the associated genes. Advances in understanding the role of the repeat expansions in FRAXE and FRAXF and associated genomics and models are presented.
Teaching introductory programming through reusable learning objects: a pilot study

This paper describes a pilot study that examines the perceived effectiveness and usability of a dynamic reusable learning object that enriches lecture material in an introductory programming course. In particular, we focus on the topic of looping by providing students an interactive tool that lets them simulate and review the execution of code. The results suggest that students in CS0 courses may utilize this tool for learning about looping, while CS1 students are more likely to use it for reviewing concepts that they learned in class. The findings of this pilot study have enabled us to focus on which aspects to improve for the next set of reusable learning objects.
Deformation Analysis of Boron/Aluminum Specimens by Moire Interferometry

Whole-field surface deformations were measured for two slotted tension specimens from multiply laminates, one with 0 deg fiber orientation in the surface ply and the other with 45 deg orientation. Macromechanical and micromechanical details were revealed using high-sensitivity moire interferometry. Although global deformations of all plies were essentially equal, numerous random or anomalous features were observed. Local deformations of adjacent 0 deg and 45 deg plies were very different, both near the slot and remote from it, requiring large interlaminar shear strains for continuity. Shear strains were concentrated in the aluminum matrix. For 45 deg plies, a major portion of the deformation was by shear; large plastic slip of matrix occurred at random locations in 45 deg plies, wherein groups of fibers slipped relative to other groups. Shear strains in the interior, between adjacent fibers, were larger than the measured surface strains.
What Influences a Plastic Surgery Resident to Pursue an Academic Career

Background A previous study demonstrated that independent model plastic surgery residents are less likely to pursue a career in academic surgery than those graduating from other surgical fellowships. This study was designed to evaluate whether a significant curriculum change emphasizing academic plastic surgery skills would be significant in influencing a plastic surgery resident's decision to pursue a career in academic plastic surgery. Methods A survey was sent to 30 consecutive graduates of a university plastic surgery residency program. This program had transitioned from a clinically focused independent residency-training model to an integrated model with a new and structured academic emphasis. Respondents who graduated after this transition ("ACADEMIC" n = 19) were compared with those who graduated before ("CLINICAL" n = 9). Results were analyzed using Fisher's exact test and Wilcoxon rank sum test. Results There were a total of 28 respondents (response rate = 93%). A higher percentage of the ACADEMIC group, in contrast to the CLINICAL group reported that they spent time during residency performing clinical research (84% versus 33%, P = 0.013), and that they are currently conducting clinical research in their practices (79% versus 0%, P < 0.001). These graduates were also more likely to have engaged their mentor both regarding professional issues (61% versus 0%, P = 0.016), and as a role model when choosing a career plan (72% versus 17%, P = 0.050). Finally, a higher percentage of the ACADEMIC exposed group entered an academic practice after training (44% versus 0%, P = 0.026). Conclusion In a single plastic surgery residency program, the transition to strong academic mentorship with a structured academic educational program focus correlated with an increase in academic careers among program graduates. A proactive academically oriented educational and mentoring environment may help attract residents to careers in academic surgery.
Sphalerite-bearing detrital `sand' bodies in Mississippi Valley-type zinc deposits Mascot-Jefferson City district, Tennessee. Implications for the age of mineralization

The Mississippi Valley-type sphalerite mineralization in the Mascot-Jefferson City zinc district of East Tennessee occurs as open-space fillings in breccia bodies within the upper part of the Knox Group (Lower Ordovician) which is truncated by a regional unconformity. A lower age limit of mineralization is constrained by the formation of solution-collapse breccia bodies, which are believed to be related to the post-Knox unconformity. The breccias contain irregularly distributed “sand” bodies that represent cavities filled with well-laminated and size-graded, sphalerite-bearing, detrital, internal sediments. The texture, composition, and fluid inclusion characteristics of the sphalerite, are consistent with its local derivation from the wallrocks as detrital grains. The conformability between the laminations in the sediments and the bedding planes of the host carbonate rocks suggests that the sand bodies formed prior to the regional deformation event (Alleghenian orogeny). The stylolitization of carbonate and sphalerite clasts in the internal sediments as well as the deformation of the sphalerite are also consistent with a pre-Alleghenian age for the emplacement of the main-stage sphalerite mineralization in the Mascot-Jefferson City district and, by analogy, in other Lower Ordovician-hosted Mississippi Valley-type districts of the southern Appalachians.
Task-Based Control and Design of a BLDC Actuator for Robotics

This letter proposes a new multi-input brushless dc motor current control policy aimed at robotics applications. The controller achieves empirical improvements in steady-state torque and power-production abilities relative to conventional controllers, while retaining similarly good torque-tracking and stability characteristics. Simulations show that non-conventional motor design optimizations, whose feasibility is established by scaling model extrapolations from existing motor catalogs, can vastly amplify the effectiveness of this new control strategy.
Gender Dysphoria and Suicidal Ideation: Clinical Observations from a Psychiatric Emergency Service.

Adolescent gender dysphoria is increasingly common. There has been documentation of the association of gender dysphoria with numerous other psychiatric conditions as well as attempted and completed suicide. The literature is unsettled on specific risk factors for self-harm within this population. Though there are published recommendations, there appears to be a need for additional clinical evidence for the determination of the safest and most effective treatment strategies for adolescent gender dysphoria. This clinical observation describes the unique case of an adolescent with gender dysphoria, severe body dysmorphia, and suicidal ideation who presented for emergency psychiatric evaluation. Gender-affirming hormone therapy had been administered to this patient at the age of 13, well earlier than published guidelines, though it was discontinued after a short course due to persistent gender uncertainty and distress. This case provides an opportunity to consider the complexity of adolescent gender dysphoria, including the unique individual features that affect the risk for self-harm and how treatment history may be related. With an increasing prevalence of gender dysphoria in this population, it is essential that every provider who cares for adolescents be well informed and prepared to recognize and respond to these risks.
Approximation of Closest Unstable Equilibrium Points via Nonlinear Modal Decoupling

The recently proposed Nonlinear Modal Decoupling (NMD) approach provides a new way for the stability analysis of large non-linear multi-oscillator systems such as power systems. NMD inversely constructs as many decoupled nonlinear oscillators as the system's oscillation modes so that individual decoupled oscillators can be easily analyzed to infer dynamics and stability of the original system. This paper presents a theoretical investigation of the consistency of the stability information between the decoupled system and the original system in terms of equilibrium points. A procedure for the approximation of closest unstable equilibrium point via nonlinear modal decoupling is proposed. The IEEE 9-bus power system is used to test the performance of this procedure.
Chapter 22 – W. Boehm: Differential Geometry II

Publisher Summary This chapter discusses differential geometry. It also discusses the parametric surfaces and arc element. To avoid potential problems with undefined normal vectors, one can assume that both families of isoparametric lines are regular. Any change of the parameters will not change the shape of the surface. It is of great importance for the further development of material. The arc element being a geometric invariant of the curve through the point x, does not depend on the particular parameterization chosen for the representation of the surface. For Meusnier's theorem, one considered (osculating) planes that contained a fixed tangent at a point on a surface. One will now look at (osculating) planes containing the normal vector at a fixed point x. This illustrates the appearance of a pair of hyperbolas as they appear when intersecting the surface in distances.
Toward Human-Level Artificial Intelligence.

In this paper, we present our research on programming human-level artificial intelligence (HLAI), including 1) a definition of HLAI, 2) an environment to develop and test HLAI, and 3) a cognitive architecture for HLAI. The term AI is used in a broad meaning, and HLAI is not clearly defined. I claim that the essence of Human-Level Intelligence to be the capability to learn from others' experiences via language. The key is that the event described by language has the same effect as if the agent experiences it firsthand for the update of the behavior policy. To develop and test models with such a capability, we are developing a simulated environment called SEDRo. There is a 3D Home, and a mother character takes care of the baby (the learning agent) and teaches languages. The environment provides comparable experiences to that of a human baby from birth to one year. Finally, I propose a cognitive architecture of HLAI called Modulated Heterarchical Prediction Memory (mHPM). In mHPM, there are three components: a universal module that learns to predict the next vector given the sequence of vector signals, a heterarchical network of those modules, and a reward-based modulation of learning. mHPM models the workings of the neocortex but the innate auxiliary units such hippocampus, reward system, instincts, and amygdala play critical roles, too.
Timeliness Through Telephones: Approximating Information Freshness in Vector Clock Models

We consider an information dissemination problem where the root of an undirected graph constantly updates its information and we wish to keep everyone in the graph as freshly informed about the root as possible. Our synchronous information spreading model uses telephone calls at each time step, in which any node can call at most one neighbor, thus inducing a matching over which information is transmitted at each step. These matchings that define the schedule over time ad infinitum are specified in a centralized manner. We introduce two problems in minimizing two natural objectives (Maximum and Average) of the latency of the root's information at all nodes in the network. First we show that it suffices to consider periodic finite schedules with a loss of at most a factor of two in each of these objectives. Next, by relating the maximum rooted latency problem to minimizing the maximum broadcast-time, we derive new approximation algorithms for this version. For the average rooted latency objective, such an approach introduces a necessary logarithmic factor overhead. We overcome this and give a constant-factor approximation for trees by devising near-optimal schedules that are locally periodic at each node and where each node has the same offset value in hearing fresh information from its parent. The average latency version motivates the problem of finding a spanning tree that minimizes a new Average Broadcast Time objective in graphs, which is interesting in its own right for future study.
A Classification and Analysis of Short-Term Retention Codes in Pigeons

Publisher Summary This chapter examined three alternative hypotheses about the nature of the code that exists between a sample stimulus and a response in simple conditional discrimination experiments. Each of the three types of codes considered mediate between the sample and the response to test under some conditions. Observation of conditional discrimination performance is not sufficient to determine the type of code which is occurring. Evidence comes from experiments where (1) the situation is arranged so that the different possible types of codes refer to discriminably different properties such as when sample stimuli are colors and test stimuli are line orientations; and (2) the situation is arranged so that error patterns or other response measures that are sensitive to interference or facilitation can be used, and the effects of operations known to influence one code but not another can be analyzed. Sample code may be unified with more than one attribute represented in a single code, or multiple sample attributes may be coded separately. Codes may or may not include information concerning the appropriate response.
Wag the Dog? Online Conferencing and Teaching

Web-accessible conferencing softwareand ``conversational ethics'' drawn from Habermas andRawls have successfully brought together on-lineparticipants separated by geography and viewpoint, andoccasionally resulted in consensus regarding otherwisedivisive issues such as abortion. The author describessuccesses, limitations, and costs of incorporatingthese technologies and discourse ethics in a religiousstudies class. Results are striking, but thepedagogical benefits involve technical risks and highlabor and time costs. This experience, coupled withrecent research, suggests that electronic pedagogies,like other teaching strategies, work for some, but notall students: this argues that we take up electronicteaching as one approach among many.
The Commonality of Difference: Teaching about Diversity in Field Instruction.

This paper discusses a study undertaken to determine the perceptions of new field instructors about the impact on the teaching/learning relationship of differences between them and their students. The differences and similarities arising in the tutorial relationship often parallel those in practice and provide many "teachable moments" about the significance of diversity for social workers. In a metropolitan social work program, new field instructors representing a wide range of fields of practice responded to a question asking them to consider the impact on the educational experience of "cultural, ethnic, gender, class, and age characteristics, and the implications of these similarities and/or differences for the teacher/learner relaionship." Asking the question succeeded in focussing the attention of field instructors on the significant but often unacknowledged impact of diversity in the educational encounter. A tendency for these field instructors to minimize differences may derive from their efforts to...
Spirits and Molecules: Ethnopharmacology and Symmetrical Epistemological Pluralism

ABSTRACTEthnopharmacology is the scientific study of indigenous drugs. Herein, I discuss some of the metaphysical issues at stake when rendering traditional medicines scientifically legible. I draw on my laboratory experience, my limited experience with Amazonian shamanism, and the ethnographic literature to consider drugs as relational entities animated in their particular cosmological milieu, with wider historical determinants stabilizing their ontologies. In relation to the problem of incommensurability that comes to the fore in ethnopharmacology, I review the broad problems faced by ethnopharmacology researchers, and extending Daston's concept of ‘applied metaphysics’ from history of science, I analyse ethnopharmacology as a process of synchronic translation across distinct regimes of knowledge and practice, offering insights into an anthropology of incommensurability that rests upon symmetrical epistemological pluralism. This theory may facilitate ethnopharmacologists and anthropologists in negotiati...
Molecules in interstellar space - Introductory remarks

The recognition that interstellar space is filled with an exceedingly tenuous gas goes back to a paper by Eddington in 1926 in which he showed that the stationary Ca + and Na lines observed in distant stars are due to Ca + ions and Na atoms present in the space between the stars. The discovery of further atoms and of the first molecules was made possible by the development of high-dispersion spectrographs for stellar spectroscopy, especially the Coude spectrograph at Mount Wilson Observatory. Dunham & Adams (1937 b) observed with this instrument, in addition to absorption lines of interstellar Ti+, K and Fe, three very sharp lines at 4300.31, 4232.58 and 3957.74 As, which they could not identify. It was Swings & Rosenfeld (1937) who pointed out that the first of these lines coincides with the R 2(£) line of the well known CH band at 4315 A.
Cause and Control of Muskellunge Fry Mortality at Chautauqua Hatchery, New York

Abstract In 1966-67, 1970, and 1973-76, New York State's muskellunge (Esox masquinongy) hatchery, located on Chautauqua Lake, sustained total or near total losses of muskellunge fry at or near the swim-up stage of development. Eggs incubated at the Chautauqua Hatchery and transferred to other stations resulted in swimming fish, but those held at Chautauqua did not. The chemistry of lake and well water at the muskellunge hatchery showed no departures from normal. During the production seasons of 1974 through 1976 the hatchery was operated on a controlled, experimental basis in an attempt to determine the cause of the fry losses. Fry die-offs could be correlated with neither the physical or chemical properties of the water nor with the presence of a fish pathogenic virus or pathological tissue changes. Controlled laboratory experiments strongly implicated bacteria as the agents responsible for the muskellunge fry losses. Organisms recovered included predominately Pseudomonas sp., although Aeromonas hydrophi...
Nonepithelial tumors of the nasal cavity, paranasal sinuses, and nasopharynx. A clinicopathologic study. XIII: Meningiomas.

Twenty cases of a rare tumor, chordoma involving the nasal cavity, paranasal sinuses, or nasopharynx, are reported. Patients most often had localized headache, nasal obstruction, decreased hearing, or symptoms related to cranial nerve involvement, especially diplopia. A mass bulging into the nasopharynx, posterior nasal cavity, or pharynx was found on physical examination in 13 of these 20 patients, and in another 6 patients on radiologic examination. Paralysis of one or more cranial nerves was identified in the majority of patients who had tumors involving the upper nasopharynx. On radiologic examination, bone destruction was frequently identified in the clivus and sphenoid areas, and less commonly in the cervical vertebrae. Each patient had biopsy-proven tumor in the nasopharynx or sphenoid areas. Patients usually were treated by combinations of surgery and radiotherapy, in some cases leading to prolonged periods of apparent tumor control. Radiotherapy frequently resulted in regression of symptoms, sometimes lasting many months or years. A few tumors that involved mainly the lower nasopharynx were more amenable to surgical resection, in one case leading to apparent tumor control. In those cases with adequate follow-up information, most patients had either died of their disease or were living with recurrent or persistent inoperable tumor. Some patients lived for many months or years between recurrences or with known tumor, indicating that chordomas often are slowly growing neoplasms. The histologic features of these chordomas are described and illustrated, and the histopathologic differential diagnosis is discussed.
The response of the marine boundary layer to mesoscale variations in sea-surface temperature

Abstract The effects of variations in sea-surface temperature on the surface fluxes of the marine atmospheric boundary layer have been investigated. The boundary model developed by Brown and Brown and Liu has been used to estimate these effects for near neutral conditions. Data taken on September 1, 1978, during the JASIN experiment have been used to corroborate the results obtained with Brown's model. Some speculations on secondary effects of the sea-surface temperature are given.
Characterization of branched polyethylene fractions from the elution column

Fractions from several elution column runs on samples of up to 6 g. of a well-characterized high-pressure polyethylene were analyzed by absolute molecular weight methods and several other techniques. The Mn and Mw integral distribution curves are free from any reversal, as was the viscosity distribution curve. Fractions with Mw as high as 8 × 106 were recovered, more than 20 times higher than the original sample's Mw. The polydispersity of the fractions increases from Mw/Mn = 1.5 or less in the low molecular weight fractions to a nearly constant value of 4.5–5.0 in fractions above 60% cumulative sample weight. Nonetheless, refractionation on the elution column shows that the fractions are narrowly distributed in terms of solubility, while GPC analysis reveals that the fractions have an extremely narrow size distribution. It is concluded from the combined results that long-chain branching plays an important role in determining the equilibrium solubility and, further, that long-chain branching increases the polymer solubility. Sample calculations are provided, which illustrate the effect of fraction polydispersity on calculated original sample molecular weights and the fit of the fractionation results to several model distribution functions.
Aerodynamic and Morphological Properties of Carbon-Fiber Aerosols

Aerodynamic size analysis and electron microscope studies of the carbon-fiber aerosol particles generated in cutting and grinding virgin carbon fibers and their laminates showed the presence of a significant quantity of respirable, fiberlike particulates, presumably caused by fiber splitting. The mass median aerodynamic diameter (MMAD) of the fiber particles, sampled from a point 10 cm above the workpiece, was 4.0 μm, which was considerably smaller than the geometric diameter (7–8 μm) of the original individual fibers. The microscopic analysis showed that small quantities of fiber fragments had sharp edges, possibly resulting from splitting of the fibers during the machining process. The resin binders when exposed to temperatures of above 400°C vaporized and generated condensation aerosol particles in the accumulation mode with an MMAD of 0.77 μm. The carbon fibers when exposed to temperatures of above 850°C began to oxidize, which resulted in diminished diameters and significant changes in their structur...
Structure of N,N-[bis(2-pyridylmethyl)-gamma-aminobutyrato]copper(II) bromide methanol solvate.

[Cu(C16H18N3O2)]Br.CH4O, Mr = 459.83, orthorhombic, P2(1)2(1)2(1), a = 10.452 (4), b = 12.197 (7), c = 14.984 (6) A, V = 1910 (3) A3, Z = 4, Dm = 1.61 (1), Dx = 1.599 g cm-3, lambda(Mo K alpha) = 0.71073 A, mu = 32.37 cm-1, F(000) = 932, T = 174 K, R = 0.0396, wR = 0.0419, 1146 observed reflections [I greater than 3 sigma(I)]. The title compound is a polymeric species in the solid state, with a unit cell consisting of two segments of one-dimensional chains. The ligand, a derivative of gamma-aminobutyric acid in which the amino group is substituted with two 2-pyridylmethyl moieties, coordinates to one copper atom through the three nitrogen atoms and to another copper atom through the two carboxylate oxygen atoms. The copper(II) atom has a pseudo square-pyramidal geometry, distorted by a distant sixth interaction to a carboxylate oxygen atom [Cu-O(2), 2.770 (7) A].
Local recurrence of renal cell carcinoma causing duodenal-inferior vena caval fistula: Case report and review of the literature

We report the first case of a duodenal-inferior vena caval (IVC) fistula resulting from locally recurrent renal cell carcinoma (RCC). A 45-year-old man presented with gross hematuria and underwent a right radical nephrectomy to treat a solid renal mass. Histologic evaluation showed RCC, Stage pT3aN0M0. The patient presented 21 months later in hemorrhagic shock, with upper gastrointestinal bleeding. He underwent an exploratory laparotomy and Whipple procedure for a mass in the second portion of the duodenum extending to the inferior vena cava with a secondary duodenal-IVC fistula. We describe this case and review the previously published reports of duodenal-IVC fistulae.
Poor in vivo reproducibility of gastric intramucosal pH determined by saline-filled balloon tonometry

Abstract Purpose: The reproducibility of gastric intramucosal pH (pHi) determinations by saline-filled balloon tonometry has not been assessed adequately. We examined the agreement of pHi obtained using pairs of tonometry catheters under various conditions in a canine model of global hypoxia. Methods: Two gastric balloon tonometry catheters were inserted into each of 16 anesthetized dogs. Cimetidine was administered to six of the animals (group 1). Hypoxia was induced for 30 minutes by reducing the FlO2 to 0.08. pHi was determined under basal conditions, at completion of hypoxia, and during the posthypoxic period. Results: The mean bias of the paired pHi determinations was 0.03 for group 1 and 0.00 for group 2 (P = NS). The corresponding 95% limits of agreement spanned 0.24 and 0.28 pH units, respectively. Agreement of pHi determinations between tonometry catheters was not significantly affected by varying of the equilibration period, by administration of cimetidine, or by the presence of posthypoxic conditions. Conclusions: Clinically important disagreement was observed in simultaneous pHi determinations obtained using separate gastric balloon tonometry catheters exposed to identical in vivo conditions. Poor reproducibility of individual pHi determinations may limit the accuracy of pHi obtained by gastric balloon tonometry in the clinical setting.
Chromosomal interchanges in plants

The foregoing survey of the literature shows that translocations are of wide-spread occurrence in plants. Most of them have been found in the angiosperms: in 49 genera of dicots and 47 genera of monocots; but some have been reported in the gymnosperms (in two genera), also in the fungi. Studies at meiosis will undoubtedly reveal translocations in many other species, either in occasional plants or in different groups isolated geographically. In certain cases they seem to have played a part in the evolution of present karyotypes. In a number of cases, the presence of translocations has not been definitely established, but they are one possible explanation of the observed configurations. The survey reveals the need for additional detailed studies of interchanges. What accounts for directed segregation in the interchange rings in certain species? For each of the factors which has been suggested there is one or more species which does not behave in the predicted manner. Experimentally produced interchanges in other species having these features would be useful; also in species having directed segregation of the sex chromosomes. A discussion of how they have been and how they might be used as tools in the investigation of other cytological and cytogenetic problems and also certain applications to practical breeding have been included.
SURFACE PRESSURE MEASUREMENTS AT THE TIP OF A MODEL HELICOPTER ROTOR IN HOVER

Surface pressures were measured near the tip of a hovering single-bladed model helicopter rotor with two tip shapes. The rotor had a constant-chord, untwisted blade with a square, flat tip which could be modified to a body-of-revolution tip. Pressure measurements were made on the blade surface along the chordwise direction at six radial stations outboard of the 94 percent blade radius. Data for each blade tip configuration were taken at blade collective pitch angles of 0, 6.18 and 11.4 degrees at a Reynolds number of 736,000 and a Mach number of 0.25 both based on tip speed. Chordwise pressure distributions and constant surface pressure contours are presented and discussed.
Stable fly phenology in a mixed agricultural--wildlife ecosystem in northeast Montana.

ABSTRACT The stable fly, Stomoxys calcitrans (L.), is a cosmopolitan species of blood-feeding Muscidae and an important pest of cattle. Although the cattle industry is the largest commodity in Montana, no research has been conducted on the abundance, distribution, or impact of stable flies in the state. Observations of stable flies attacking West Nile virus (family Flaviviridae, genus Flavivirus, WNV) -infected pelicans on a refuge in close proximity to pastured and confined cattle provided an opportunity to describe stable fly phenology in a mixed agricultural-wildlife ecosystem. Coroplast cards used to monitor and compare adult populations in three habitats (peninsula, pasture, confinement lot) located within 1.5–4.5 km of each other revealed that temporal dynamics differed by site. Adult abundance was generally lowest at the confinement lot, the only location where larval development was identified. Stable flies were collected on all traps placed in pasture, with traps adjacent to pastured cattle consi...
Classification of vertebral fractures

Although it is a cardinal feature of involutional osteoporosis, there is often disagreement on what constitutes a vertebral fracture. We measured vertebrae T4-L5 in 52 healthy women to develop a normal range (mean +/- 3 SD) for vertebral shape and used these data to assess the prevalence of vertebral fractures. We classified vertebral fractures by type of deformity (wedge, biconcavity, or compression) and further by the degree of deformity (grades 1 and 2). In 195 postmenopausal women who were an age-stratified random sample of the Rochester population (ages 47-94), 40 (21%) had vertebral fractures (mean, 2 per person). There was a similar number of compression and wedge fractures, and grade 2 fractures were as common as grade 1. In a referral sample of 74 women with suspected osteoporosis, 62 (84%) had vertebral fractures (mean, 3.3 per person). Wedge fractures were most common, and grade 2 fractures were more common than grade 1. The distribution of type and grade of fractures differed between the two patient groups (P less than 0.01). Bone mineral density of the lumbar spine was related to mean fracture grade (r = -0.33, P less than 0.05) and to fracture number (r = -0.57, P less than 0.001) but not to fracture type. We conclude that a comprehensive approach is required in describing vertebral fractures. Using this approach we found distortion in the fracture characteristics of women referred to an osteoporosis clinic compared to women in the community.
Binding of Diamines to n-Butyllithium Dimers: Relative Solvation Energies and Evidence of Correlated Solvation

Polyamines such as N,N,N′,N′-tetramethylethylenediamine (TMEDA) have had an enormous impact within organolithium chemistry.1,2 However, despite extensive structural and mechanistic studies,2,3 it is still not clear how chelating ligands influence organolithium structure and reactivity.3 As part of an effort to understand structure-reactivity relationships in organolithium chemistry, we have been investigating the role of TMEDA and related chelating ligands.4 We describe herein spectroscopic investigations of n-butyllithium (n-BuLi) solvated by an assortment of vicinal diamines.5,6 These studies reveal highly liganddependent solvation energies and correlated solvation effects.
A computational model of the response of adherent cells to stretch and changes in substrate stiffness

Cells in the body exist in a dynamic mechanical environment where they are subject to mechanical stretch as well as changes in composition and stiffness of the underlying extracellular matrix (ECM). However, the underlying mechanisms by which cells sense and adapt to their dynamic mechanical environment, in particular to stretch, are not well understood. In this study, we hypothesized that emergent phenomena at the level of the actin network arising from active structural rearrangements driven by nonmuscle myosin II molecular motors play a major role in the cellular response to both stretch and changes in ECM stiffness. To test this hypothesis, we introduce a simple network model of actin-myosin interactions that links active self-organization of the actin network to the stiffness of the network and the traction forces generated by the network. We demonstrate that such a network replicates not only the effect of changes in substrate stiffness on cellular traction and stiffness and the dependence of rate of force development by a cell on the stiffness of its substrate, but also explains the physical response of adherent cells to transient and cyclic stretch. Our results provide strong indication that network phenomena governed by the active reorganization of the actin-myosin structure plays an important role in cellular mechanosensing and response to both changes in ECM stiffness and externally applied mechanical stretch.
Biomechanics and Biology of External Fixation of Distal Radius Fractures

External fixation of distal radius fractures is only one of several ways to approach this complex injury. In fact, widespread analysis of clinical outcomes of distal radius fractures still fails to show improved clinical outcomes from any specific surgical treatment modality [1]. Loss of reduction, the commonest complication of distal radius fractures, can be prevented with the application of an external fixator, a simple technique that is surgically minimally invasive. Complications such as pin loosening and pin track infection, wrist and finger stiffness, and complex regional pain syndrome, however, have been reported following the use of external fixation for the management of distal radius fractures [2,3]. In contradistinction to internal fixation of a fracture with an intramedullary nail or plate by following a defined operative technique, application of an external fixator entails considerable planning with regard to insertion of the anchoring pins and construction of the external supporting frame. In addition, external fixator use also requires closer supervision and follow-up in the postoperative period for mechanical (clamp retightening, angular adjustment) and biologic (pin site care) reasons. This article reviews the mechanical properties of external fixation and current concepts of the biology of bone healing and the pin–bone interface. In addition, the concept unique to the treatment of distal radius fractures—ligamentotaxis—is discussed, with attention to mechanics of reduction and the adverse effects of prolonged traction on soft tissues.
THE COST OF COLOR

![Figure][1] When it comes to genomes, most mammals don't stint on their sense of smell. A substantial proportion of the mammalian genome is devoted to olfaction, and conservative estimates indicate that odorant receptor genes number in the hundreds. However, the significance of the size of
Metacomprehension during basal reader instruction: Do teachers promote it?

Abstract Much of the research and instructional development on metacomprehension has been based on the premise that students are in need of such instruction because teachers do little to foster students’ metacomprehension ability. However, this assertion has not been tested empirically; therefore, it was the purpose of this study to analyze elementary teachers’ interactions with their students during the guided reading of basal reader selections in order to determine the extent to which they do promote students’ metacomprehension abilities. Results indicated that teachers did very little to foster students’ metacomprehension abilities during the guided reading of basal selections. The procedures related to metacomprehension that were detected revealed that the teachers assumed most of the responsibility for students’ comprehension themselves rather than directing students to engage in metacomprehension strategies or conducting the lessons in a manner that promoted metacomprehension abilities. Instructiona...
alpha-Difluoromethylornithine, an irreversible inhibitor of ornithine decarboxylase, inhibits tumor promoter-induced polyamine accumulation and carcinogenesis in mouse skin

Abstract The role of ornithine decarboxylase (OrnDCase, EC 4.1.1.17) and of the polyamines [putrescine (Put), spermidine (Spd), and spermine (Spm)] in mouse skin tumor promotion was investigated by the use of alpha-difluoromethylornithine (CHF2-Orn), an enzyme-activated irreversible inhibitor of OrnDCase. 12-O-Tetradecanoylphorbol 13-acetate (TPA), mezerein, and ethyl phenylpropiolate (EPP) were employed as complete, stage II specific, and nonpromoting agents, respectively. TPA and mezerein, but not EPP, provided for a dose-dependent increase in tissue Put accumulation. The Put level in papillomas developed by TPA (2 micrograms) treatment was approximately equal to 15-fold higher than that of the surrounding skin tissue; Spd accumulation was 2- to 3-fold greater in the papillomas. Put administered (intraperitoneally) with TPA greatly enhanced papilloma yield. CHF2-Orn, given orally or intraperitoneally, abolished the TPA-induced OrnDCase activity and Put accumulation in mouse epidermis. The reduction of polyamine accumulation by CHF2-Orn was directly proportional to reduction of tumor size. CHF2-Orn administered in a two-stage (TPA-mezerein) promotion protocol [Slaga, T. J., Fischer, S. M., Nelson, K. G. & Gleason, G. L. (1980) Proc. Natl. Acad. Sci. USA 77, 3659-3663; Slaga, T. J., Klein-Szanto, A. J. P., Fischer, S. M., Weeks, C. E., Nelson, K. & Major, S. (1980) Proc. Natl. Acad. Sci. USA 77, 2251-2254] reduced tumor size, inhibited by 65-70% the number of papillomas per mouse, and decreased by 40% the percentage of mice with tumors when given with the stage II agent mezerein. CHF2-Orn provided considerably less effect on tumorigenesis when administered with the TPA portion of the protocol, and CHF2-Orn did not inhibit the induction of dark basal keratinocytes by TPA. Based on our results with CHF2-Orn, we suggest that regulation of polyamine biosynthesis, particularly Put, is a critical factor in stage II promotion.
The “case” method in modern educational psychology texts

Abstract Modern educational psychology texts emphasize knowledge application. This paper analyzes how current texts use “case” materials to enhance transfer to the realm of application. The framework for this review is recent cognitive learning research and problem-based learning from medicine. Results showed texts use very different case-based activities and each type of activity has its strengths and weaknesses relative to its placement in the text, instructional strategy, case content and structure, and likelihood for transfer. Minor changes in, as well as some radical recastings, of the “case” method used by educational psychology texts are needed.
An Examination of the Validity of Direct Product Perceptions

The validity of a class of direct product perceptions is examined. Consumers recorded their perception of different products directly within exisiting spatial or treelike representations of the products' competitors. A conceptual model is developed that describes consumers' ability to provide direct perceptions within both space and tree representations for both brands and product categories. An empirical study is reported which supports the model and the validty of the recorded perceptions.