cssi/SciSciGPT-SciSciNet huggingface dataset:
Long-term indomethacin therapy decreases fetal urine output and results in oligohydramnios

Four quadrant quantitative amniotic fluid volume (length, width, and depth) was performed in six fetuses prior to and during indomethacin therapy for preterm labor in patients with normal amniotic fluid volume prior to therapy. The dose of indomethacin was 25 mg orally every 6 hours. One patient had to have the dose reduced to 25 mg every 12 hours due to constriction of the ductus arteriosus. Fetal urine output was determined prior to and during indomethacin therapy. The mean pretherapy amniotic fluid volume of 341.5 +/- 43.2 mm declined to 97 +/- 9.3 mm at the time of discontinuation of indomethacin for oligohydramnios. This occurred after 15 days of 25 mg indomethacin orally every 6 hours in four patients and after 28 days at 25 mg indomethacin every 12 hours in the remaining patient. Fetal urine output prior to and following indomethacin was 4.93 +/- 14 ml and 1.73 +/- 0.6 ml/hr, respectively. Prolonged indomethacin therapy results in decreased fetal urine output with resultant oligohydramnios and appears to be the major limiting factor aside from ductal constriction to long-term indomethacin therapy.
CD10, p63 and CD99 expression in the differential diagnosis of atypical fibroxanthoma, spindle cell squamous cell carcinoma and desmoplastic melanoma.

Background Atypical fibroxanthoma (AFX) is a pleomorphic spindle cell lesion of the skin; it is considered in the differential diagnosis with spindle cell malignant melanoma (MM) and sarcomatoid carcinoma/spindle cell squamous cell carcinoma (SCC). An optimum approach has yet to fully emerge with respect to the immunohistochemical discrimination of these lesions. Methods Departmental archives from 1978 onwards were searched for clinicopathologically confirmed cases of AFX, MM and SCC. Immunostains for CD10, CD99 and p63 were performed in each case. Scored staining results were analyzed using Fisher's Exact Test. Results Twenty-seven of 31 cases of AFX were positive for CD10, as compared with 3 of 22 SCCs and 0 of 20 MMs. CD10 positivity was preferentially associated with the diagnosis of AFX (p Conclusion CD10 positivity is relatively specific in this context for the diagnosis of AFX. Its utility is enhanced when only strong, diffuse membranocytoplasmic staining is considered as a positive result. In contrast to prior reports, p63 was not found to be highly sensitive for SCC. Similarly, CD99 showed no preferential staining of any single diagnostic group of lesions.
Modeling and Simulation of Peristaltic Transport and Mixing in the Human Gastrointestinal Tract

Despite active research, the mechanism by which food is transported, mixed and absorbed in the human gastro-intestinal tract remains poorly understood. At the University of Iowa Veterans Hospital, clinicians have been treating veterans for abnormal mechanical activity of the stomach and intestine and are pursuing research into such mechanisms, in order to better control and treat such ailments. The pathology experienced by these patients tends to be chronic and somewhat refractory to treatment particularly in the elderly, those with diabetes or after abdominal operations. Abnormal activity is responsible for gastro-esophageal reflux, gastroparesis, diarrhea, and abdominal pain syndromes. Current techniques of imaging and of image analysis should steadily improve ability to obtain information on mechanical activity of stomach and intestines in patients. Yet, for these imaging techniques to provide optimal diagnostic information, one needs to understand, in depth, how the visual parameters of contractions relate to digestion and absorption of nutrients.Copyright © 2002 by ASME
Chromoblastomycosis and phaeohyphomycosis: New concepts, diagnosis, and mycology

The nomenclature for the mycoses caused by dematiaceous fungi should represent the combined clinical, pathologic, and mycologic relationships exhibited in the diseases. Chromoblastomycosis encompasses chronic, localized infections of the cutaneous and subcutaneous tissues that contain sclerotic bodies and histologically show hyperkeratotic pseudoepitheliomatous hyperplasia with keratolytic microabscess formation in the epidermis. In contrast, phaeohyphomycosis is a collective term for a heterogenous group of mycotic infections that contain dematiaceous yeastlike cells, pseudohyphae-like elements, hyphae, or any combination of these forms in tissue. The terms superficial, cutaneous and corneal, subcutaneous, and systemic phaeohyphomycosis are proposed for the major categories of phaeohyphomycosis. The term chromomycosis is rejected for mycoses caused by the dematiaceous fungi.
A study of mixtures of HfO 2 and TiO 2 as high- k gate dielectrics

HfxTi1-xO2 films have been deposited by chemical vapor deposition. Permittivities of approximately 50 have been obtained. The films are stable up to 1000 °C. The interface properties and charge trapping appear to depend on composition. For films with approximately equal Hf and Ti concentration, transistor characteristics and inversion layer mobilities are comparable to those obtained when using pure HfO2.
Vibrattonal excitation of molecules by collisions with “hot” hydrogen atoms from laser photolysis

Abstract Excimer laser (ArF) photolysis of diatomic and triatomic hydrides produces hydrogen atoms with translational energies in excess of 15000 cm −1 per atom. Subsequent collisions of these “hot” atoms with CO 2 and N 2 O produces vibrationally excited molecules which can be detected by their characteristic infrared emission.
Defense conversion: The economic conversion of the American economy

Abstract The conversion of the American defense industry has been under way for 5 years spanning both a Republican and Democratic presidential administration. The article provides a baseline data description and analysis of defense conversion in America that draws on theoretical and practical concepts from Europe on how to achieve industrial “reconversion.” The practical outcome for marketing managers is how to interpret macro events in order to structure micro plans and programs. In short, once marketing managers can understand, see, and even predict the broader economic defense conversion picture, they are able to implement new marketing strategies.
Influence of propranolol, enalaprilat, verapamil, and caffeine on adenosine A2A-receptor–mediated coronary vasodilation

AbstractObjectives: The study was done to determine the effects of propranolol, enalaprilat, verapamil, and caffeine on the vasodilatory properties of the adenosine A2A-receptor agonist ATL-146e (A...
Discovering user information needs: the case of university department web sites

University department’s web pages are the focal point for a wide variety of users, including prospective students, current students, parents, staff and alumni. We provide a task analysis of what each user group will look for on university department websites. This analysis is based on analysis of existing sites, hardcopy materials, user search query logs, and interviews with users. Good task analyses are reusable as a design aid. Checking a site to ensure that common users’ tasks can be performed will help ensure completeness of a site. Further reflection on these tasks can enhance the clarity and consistency of the procedures used when providing navigational aids. We use the task analysis to show that five existing university sites provide good but varying amounts of support for these tasks. This analysis of university websites can be applied more generally to other websites, such as a corporation, non-profit or an e-store.
New geometry of face worm gear drives with conical and cylindrical worms: generation, simulation of meshing, and stress analysis

New geometry of face worm gear drives with conical and cylindrical worms is proposed. The generation of the face worm-gear is based on application of a tilted head-cutter (grinding tool) instead of application of a hob applied at present. The generation of a conjugated worm is based on application of a tilted head-cutter (grinding tool) as well. The bearing contact of the gear drive is localized and is oriented longitudinally. A predesigned parabolic function of transmission errors for reduction of noise and vibration is provided. The stress analysis of the gear drive is performed using a three-dimensional finite element analysis. The contacting model is automatically generated. The developed theory is illustrated with numerical examples.
Identifying Enablers and Barriers to Successful Platform-Based Product Development: A Case Study From Business-to-Business Products

Product development teams are facing continued pressure to develop more products in less time and with fewer resources. Platform-based developed is commonly seen as a solution to increase capacity of the product development pipeline. This research identified enablers and barriers to successful platform-based product development. This was achieved through a comprehensive literature review of the current state of the art and an exploratory case study of product development practices within a business-to-business environment from companies with significantly different cultures and experiences with platform-based product development. Key enablers identified in this research include institutionalizing systems engineering, development and communication of product development roadmaps, augmentation of phase gate review process and critical parameter characterization. Operational recommendations from this research are considered to be possible to implement without significant changes to existing processes and organizational structures.Copyright © 2011 by ASME
Nonlinear dispersion of stationary waves in collisionless plasmas.

A nonlinear dispersion of a general stationary wave in collisionless plasma is obtained in a nondifferential form expressed in terms of a single-particle oscillation-center Hamiltonian. For electrostatic oscillations in nonmagnetized plasma, considered as a paradigmatic example, the linear dielectric function is generalized, and the trapped particle contribution to the wave frequency shift $\ensuremath{\Delta}\ensuremath{\omega}$ is found analytically as a function of the wave amplitude $a$. Smooth distributions yield $\ensuremath{\Delta}\ensuremath{\omega}\ensuremath{\sim}{a}^{1/2}$, as usual. However, beamlike distributions of trapped electrons result in different power laws, or even a logarithmic nonlinearity, which are derived as asymptotic limits of the same dispersion relation.
A generalization of even and odd functions

We generalize the concepts of even and odd functions in the setting of complexvalued functions of a complex variable. If n > 1 is a fixed integer and r is an integer with 0 r < n, we define what it means for a function to have type r mod n. When nD 2, this reduces to the notions of even (r D 0) and odd (r D 1) functions respectively. We show that every function can be decomposed in a unique way as the sum of functions of types-0 through n 1. When the given function is differentiable, this decomposition is compatible with the differentiation operator in a natural way. We also show that under certain conditions, the type r component of a given function may be regarded as a realvalued function of a real variable. Although this decomposition satisfies several analytic properties, the decomposition itself is largely algebraic, and we show that it can be explained in terms of representation theory.
Labor Cost Reduction with Cloud: An End-to-End View

This paper presents a new, compelling argument for a larger potential to reduce labor cost by adopting cloud computing in enterprise IT. The additional cost reduction is possible in the labor intensive activities of customer-specific customization of cloud services, tools support, and customer-facing service management. These essential service delivery processes are excellent candidates for standardization and automation using the cloud computing principles. We present examples of such processes and potential for optimization in these processes.
Temporal Patterns in Long-Term Survival After Resuscitation From Out-of-Hospital Cardiac Arrest

Background— During the past quarter century, advances in treatment of cardiovascular disease have occurred that might potentially benefit survivors of sudden cardiac arrest (SCA). Little is known, however, about the temporal patterns in long-term survival among persons resuscitated from SCA. We hypothesized that long-term survival would improve over time and that this temporal pattern would be most evident for cardiac causes of death. Methods and Results— The investigation was a retrospective cohort study of survival among persons who were discharged alive from the hospital after resuscitation from out-of-hospital SCA due to heart disease in King County, Wash, between May 1, 1976, and December 31, 2001 (n=2035). Calendar time was divided into four 5-year intervals: 1976 to 1980, 1981 to 1985, 1986 to 1990, and 1991 to 1995, and one 6-year interval, 1996 to 2001. Age-adjusted survival curves were constructed, and Cox proportional-hazards regression was used to compute hazard ratios (HRs) for the associatio...
Use of a double-lumen stacked expander and breast implant

Abstract Background: Several attempts have been made to develop dual-lumen self-enclosed breast implants and differentially shaped breast implants. However, they have not achieved the goal of a more anatomical configuration of the breast. Objective: This study examines the results of breast procedures, both reconstructions and secondary augmentations, in which double-lumen permanent stacked implants were used. Methods: For use in breast reconstruction, a dual-lumen stacked tissue expander was placed in a submuscular/subfascial pocket extending 2 cm below the inframammary crease. Active and then passive expansion was followed by removal of the expander and replacement with a dual-lumen permanent stacked implant. Augmentation patients underwent bilateral total open capsulectomy with removal of ruptured silicone gel implants and replacement with dual-lumen permanent stacked implants. Results: In a series of 20 patients, anatomically accurate, acceptably symmetric breasts were achieved. Conclusions: The dual-lumen permanent stacked implant yields a pleasing sloped breast profile.
Trace Metal Metabolism in Cultured Skin Fibroblasts of the Mottled Mouse: Response to Metallothionein Inducers

ABSTRACT: Menkes' kinky hair syndrome is a lethal Xlinked disorder marked by tissue-specific increases in copper content. An animal model of kinky hair syndrome is provided by mice mutant at the X-linked mottled locus. The basic defect is unknown. In order to discriminate among potential etiologies, we asked whether the expression of the mottled mutation causes abnormalities in the metabolism of trace metals other than copper in hemizygous mottled (blotchy) cultured skin fibroblasts, and whether we can differentiate mutant and normal cells according to their response to metal inducers of metallothionein. Blotchy fibroblasts accumulated up to 12 times more 64Cu than control (littermate) cells, over time and over a range of 64Cu concentrations. A saturable high affinity component to 64Cu accumulation over a fixed time interval was revealed in these studies. While 64Cu uptake kinetics were indistinguishable in mutant and control cells, the patterns of 64Cu exit differed. In both cell types, the rate of release of a rapidly exchangeable fraction of newly acquired 64Cu was similar. However, in mutant cells, a larger fraction of recently accumulated 64Cu is retained. In contrast to the results for 64Cu, accumulation and exit of 65Zn and 109Cd were not distinguishable in mutants and controls. With exposure to either a strong (cadmium) or weaker (zinc) inducer of metallothionein, 64Cu accumulation was increased in normal cells, while there was no change from the already elevated level of 64Cu accumulation in blotchy cells. In contrast, the effects of metal inducers of metallothionein on 65Zn or 109Cd accumulation in mutant cells were indistinguishable from the effects on controls. The present observations reveal that blotchy fibroblasts exhibit normal accumulation and exit of metals other than copper, and evince a differential response to metallothionein inducers, which response is also limited to the accumulation of copper. When considered together with the larger body of data on the kinky hair syndrome and mottled mutation, we infer that the defect in both species resides in the function of a thionein or other protein specifically binding copper; or in an altered transport system specifically affecting copper.
The Interaction of Text and Culture in Spanish Renaissance ‘Translations’ of Plautus’ Amphytruo

The study of translation in Spain during the Renaissance provides the modern critic with a paradoxical situation. Although the sixteenth century represents a period of prolific translation activity in Spain, there is a resonant theoretical silence among Spanish Renaissance authors and preceptistas on the procedures and methods of translating.1 While attitudes towards translation were no doubt influenced by Classical authorities—particularly Horace, Cicero, and Quintillian—no a priori models were consistently followed. Translators tended, rather, to see method as ‘the offspring of an empirical investigation of the text’.2 Through a consideration of individual practice and the function a translator assigns to language, we can elicit fragments of the theoretical structures governing any given translation. Translation, then, is a dialectical process between a source text and its re-elaboration in another language, resulting in a concurrent implicit text which is the translator's own theory of an ambiguous act...
Primary Motor Cortex Reports Efferent Control of Vibrissa Motion on Multiple Timescales

Exploratory whisking in rat is an example of self-generated movement on multiple timescales, from slow variations in the envelope of whisking to the rapid sequence of muscle contractions during a single whisk cycle. We find that, as a population, spike trains of single units in primary vibrissa motor cortex report the absolute angle of vibrissa position. This representation persists after sensory nerve transection, indicating an efferent source. About two-thirds of the units are modulated by slow variations in the envelope of whisking, while relatively few units report rapid changes in position within the whisk cycle. The combined results from this study and past measurements, which show that primary sensory cortex codes the whisking envelope as a motor copy signal, imply that signals present in both sensory and motor cortices are necessary to compute angular coordinates based on vibrissa touch.
LptE binds to and alters the physical state of LPS to catalyze its assembly at the cell surface.

The assembly of lipopolysaccharide (LPS) on the surface of Gram-negative bacterial cells is essential for their viability and is achieved by the seven-protein LPS transport (Lpt) pathway. The outer membrane (OM) lipoprotein LptE and the β-barrel membrane protein LptD form a complex that assembles LPS into the outer leaflet of the OM. We report a crystal structure of the Escherichia coli OM lipoprotein LptE at 2.34 A. The structure reveals homology to eukaryotic LPS-binding proteins and allowed for the prediction of an LPS-binding site, which was confirmed by genetic and biophysical experiments. Specific point mutations at this site lead to defects in OM biogenesis. We show that wild-type LptE disrupts LPS–LPS interactions in vitro and that these mutations decrease the ability of LptE to disaggregate LPS. Transmission electron microscopic imaging shows that LptE can disrupt LPS aggregates even at substoichiometric concentrations. We propose a model in which LptE functions as an LPS transfer protein in the OM translocon by disaggregating LPS during transport to allow for its insertion into the OM.
Natural compounds as lead therapeutic agents against diabetic eye disease

Diabetes is a leading cause of new cases of blindness throughout the world. Given the rapid increase in diabetes incidence in recent years, diabetic eye disease will likely become an even bigger problem in the future. There are currently no medical therapies for prevention of early stage ophthalmic complications of diabetes, and treatment for late stage disease is complicated and prohibitively expensive for deployment on a large scale. We have centered our efforts on identifying therapeutic compounds identified as natural products, with a particular focus on plant materials identified over time to be associated with efficacy against diabetes and its complications. The Indian gooseberry (Emblica officinalis), commonly known as Amla, is used in the practice of Indian traditional medicine (Ayurveda) to minimize the effects of diabetes and its complications. We previously showed that treatment of experimentally diabetic rats with crude extracts from Amla fruit delayed the onset and progression of cataracts and prevented the accumulation of sorbitol and diabetes-induced markers of lipid peroxidation and protein oxidation products in the eye. Because these results were consistent with the effects of aldose reductase (AR) inhibition, we embarked on a bioassay-guided scheme to search for putative AR inhibitors (ARI), using human AR (AKR1B1) activity as an assay read out. Fractionation of materials in an Amla extract resolved several compounds with ARI activity. Structure elucidation by NMR identified the major inhibitor as 1-O-galloyl-beta-D-glucose, also known as beta-glucogallin (bGG). We and others have shown that AR inhibition by sorbinil and a variety of other validated ARIs suppresses inflammatory markers associated with exposure to lipopolysaccharide (LPS) endotoxins. Our studies show that treatment of LPS-exposed mice with bGG dose-dependently suppresses infiltration of inflammatory cells in the anterior and posterior chambers and prevents morphological disruption of retinal layers. Using macrophage cell cultures, we demonstrated that bGG down-regulates endotoxin-induced expression of a variety of pro-inflammatory cytokines including TNFa and IL1b. Similar studies are being carried out with a novel drug lead recently identified in a family of flowering plants commonly cultivated in India and Malaysia (Piperaceae). Overall, our studies suggest that natural products may be a rich source of lead compounds useful for development as therapeutic agents against diabetic complications.
Whirling of a forced cantilevered beam with static deflection. III: Passage through resonance

Nonstationary excitations of slender, elastic, cantilevered beams with equal principal moments of inertia are considered. The excitation frequency is slowly increased or decreased through a resonance of the first mode at a constant rate. Three resonances are investigated: primary resonance, superharmonic resonance of order two and subharmonic resonance of order two. After application of Galerkin's method with three modes, the nonlinear, nonstationary response of the first mode of the beam is determined by two methods: integration of the modulation equations obtained from the method of multiple scales, and direct numerical integration of the temporal equations of motion. Time histories are presented and the effects of excitation amplitude, rate of acceleration or deceleration through resonance, damping and initial conditions of the disturbance on the maximum response are studied. The effect of a persistent random disturbance is also examined. Although the excitation acts in the vertical plane, whirling occurs if the beam is subjected to out-of-plane disturbances.
The effect of putative nucleation sites on the loading and stability of iron in ferritin

The L chain of the iron storage protein ferritin contains more putative nucleation sites in the core (Glu53, 56, 57, 60, and 63) than does the H chain (Glu61, 64, and 67). Recombinant DNA techniques were used to investigate the role of these putative nucleation sites on iron loading by ceruloplasmin and on the stability of the iron core. Recombinant rat liver ferritin H chain homopolymer and the two mutants (E61A and E61A-E64A), containing three, two and one nucleation sites, respectively, loaded up to 2010 +/- 50, 2010 +/- 40, and 1950 +/- 40 atoms of iron per ferritin, respectively. However, the mutations resulted in a 50% decrease in the rate of iron loading by ceruloplasmin. The ferritin variants incorporated the same amount of phosphate after iron loading (410 +/- 20, 400 +/- 30, and 420 +/- 20 atoms per ferritin, respectively). The stability of the iron cores prior to phosphate incorporation, assessed by the rate of iron release by 10 mM EDTA and the paraquat cation radical, corresponded to numbers of proposed nucleation sites. The subsequent incorporation of phosphate seemed to stabilize the iron core and minimized the effect of numbers of putative nucleation sites in ferritin on the rate of iron release by EDTA and the paraquat cation radical. After incorporation of phosphate the ferritins behaved similarly to the native rat liver ferritin with respect to the rate of iron release by the paraquat cation radical.
Structural features of low-rank coals important in liquefaction, bioconversion and gasification

Molecular weight determinations have been performed using low-angle laser light scattering photometry on derivatives of a series of humic acid macromolecules derived from lignite. The humate derivatives obtained from Beulah lignite by base extraction were shown to have molecular weights ranging from 1.3 × 106 to 4.3 × 105 daltons, low and high yield extractions respectively. Mild oxidation with p-nitroperbenzoic acid gave humic acids with slightly larger molecular weights, again inversely proportional to the yields. The nature of the aliphatic bridging groups in low-rank coals have been investigated by ruthenium tetroxide oxidations using isotope dilution GC/MS methods for analysis of the product carboxylic acids derived from oxidation of the aromatic portions of the coal.
Cytogenetic analysis in the diagnosis and management of lipoblastomas: results from a single institution

Abstract Background Lipoblastomas are rare, benign, soft tissue tumors that occur primarily in young children. Treatment includes complete excision and surveillance for recurrence. Lipoblastomas can be indistinguishable from other benign lipomatous tumors and liposarcomas. Cytogenetic analysis can provide the definitive diagnosis in questionable cases, because benign and malignant lipomatous tumors exhibit specific nonrandom cytogenetic abnormalities. The purpose of the present study was to discuss the disease management and outcomes in a large contemporary group of patients with lipoblastoma. Materials and methods A retrospective chart review of patients diagnosed with lipoblastoma presenting from 2000–2011 was conducted. The data from these patients were compared with data from a previously published historical group of patients (1985–1999) from the same children's hospital. Results We identified 37 patients in the contemporary cohort group and compared them with 25 patients from the historical group. The tumor involvement sites were similar. The current cohort group had a lower recurrence rate, although this might have been underestimated owing to a shorter follow-up period (median 1.4 y, range 2 wk to 11.0 y). Preoperative imaging findings led to an incorrect diagnosis in 62% of the patients. Cytogenetic analysis was used to help determine the final diagnosis in 50% of the cases. In 39% of cases, translocations involved the long arm of chromosome 8, the most common anomaly in lipoblastoma. Conclusions Lipoblastomas are rare tumors in young children that can be misclassified as other malignant or benign lipomatous tumors with markedly different outcomes and treatments. We recommend that cytogenetic analysis be routinely used for all pediatric lipomatous tumors to provide an accurate diagnosis and guide appropriate therapy and follow-up.
Representing refugees: the role of elites in Burundi refugee society.

Among Burundi refugees in Tanzania, men who have a university education and know English or French are most likely to represent their concerns to officials, particularly those from UNHCR. Officials consequently learn about the perspectives of refugees from these men. Based upon findings from two years of field, research in Tanzania, the history of relations between ethnic Hutu elites and the peasantry in Burundi is outlined and it is explained why education has assumed such pronounced significance in Burundi refugee society. The use of ethnicity as a political tool for elite refugees is also described. It is concluded that elite refugees may not, as is often claimed, represent the refugee majority.
Effects of Hypoxia and Hyperoxia on Lung Prostaglandin E1 Metabolism

Abstract Exposure to hypoxia (10% 02 for 5 to 7 days) results in increased survival and decreased pulmonary toxicity of adult rats subsequently exposed to hyperoxia (>97% 02). These experiments tested whether hypoxia preexposure minimized the decrease in lung metabolism of prostaglandin Ex (PGEi), a vasoactive and antiinflammatory prostaglandin, caused by hyperoxia. Transpulmonary PGEX clearance was measured as fractional metabolism of PGEi (2 fiM. to 30 fiM) infused during a 45-second period in an isolated, buffer-perfused rat lung preparation after exposure of rats to one of the following conditions: (1) hy-peroxia (>97% 02 for 48 hours), (2) hypoxia (10% 02 for 120 hours), or (3) hypoxia followed by hyperoxia. Hyperoxia exposure decreased both lung PGEi metabolism and lung prostaglandin dehydrogenase activity (PGDH). Hypoxia also decreased lung PGEi metabolism but, in contrast, increased lung PGDH activity. Hypoxia preexposure did not prevent the depression of PGEi metabolism or PGDH activity caused by hyperoxia, which indicates that survival in hyperoxia did not depend on lung PGEi metabolism. Hypoxia itself impaired transpulmonary metabolism of PGEi despite increasing PGDH activity, which suggests possible interference with substrate delivery. [Am J Med Sci 1997;313(3):147-152.]
Repeated Origin of Three-Dimensional Leaf Venation Releases Constraints on the Evolution of Succulence in Plants

Summary Succulent water storage is a prominent feature among plants adapted to arid zones, but we know little about how succulence evolves and how it is integrated into organs already tasked with multiple functions. Increased volume in succulent leaves, for example, may result in longer transport distances between veins and the cells that they supply, which in turn could negatively impact photosynthesis [1–4]. We quantified water storage [5] in a group of 83 closely related species to examine the evolutionary dynamics of succulence and leaf venation. In most leaves, vein density decreased with increasing succulence, resulting in significant increases in the path length of water from veins to evaporative surfaces. The most succulent leaves, however, had a distinct three-dimensional (3D) venation pattern, which evolved 11–12 times within this small lineage, likely via multiple developmental pathways. 3D venation "resets" internal leaf distances, maintaining moderate vein density in extremely succulent tissues and suggesting that the evolution of extreme succulence is constrained by the need to maintain an efficient leaf hydraulic system. The repeated evolution of 3D venation decouples leaf water storage from hydraulic path length, facilitating the evolutionary exploration of novel phenotypic space.
Leveraging What We Know to Enhance Short-Term and Long-Term Retention of University Students

Logistic regression models of students' 1-year retention and 6-year retention/graduation for the fall 2000 entering class of students at a research-extensive university in the Midwest were estimate...
A simplicial algorithm for the nonlinear complementarity problem

A triangulation of the nonnegative orthant and a special labeling of the vertices lead to a combinatorial procedure for seeking solutions or approximate solutions to the nonlinear complementarity problem under coercive-like assumptions on the problem functions. Derivatives are not required. Convergence is proved, computational considerations are discussed, and some preliminary applications to convex programming and saddle point computation, along with numerical results, are presented.
A hybrid model of the CO2 geochemical cycle and its application to large impact events

The effects of a large asteriod or comet impact on modern and ancient marine biospheres are analyzed. A hybrid model of the carbonate-silicate geochemical cycle, which is capable of calculating the concentrations of carbon dioxide in the atmosphere, ocean, and sedimentary rocks, is described. The differences between the Keir and Berger (1983) model and the hybrid model are discussed. Equilibrium solutions are derived for the preindustrial atmosphere/ocean system and for a system similar to that of the late Cretaceous Period. The model data reveal that globl darkening caused by a stratospheric dust veil could destroy the existing phytoplankton within a period of several weeks or months, nd the dissolution of atmospheric NO(x) compounds would lower the pH of ocean surface waters and release CO2 into the atmosphere. It is noted that the surface temperatures could be increased by several degrees and surface oceans would be uninhabitable for calcaerous organisms for approximately 20 years.
Correlation of Particulate Dispersion Stability with the Strength of Self-Assembled Surfactant Films

Self-assembled surfactant films at the solid/liquid interface are investigated as a means to impart stability to nanoparticulate suspensions in extreme environments. Resistance to elastic deformation of the surface surfactant structures is proposed as the primary stabilization mechanism. There exists a critical concentration of surfactant, above which, repulsive forces between coated surfaces are measured and particle stability occurs. This concentration does not correspond to the critical hemimicelle concentration or the bulk critical micelle concentration. Instead, it appears during bilayer formation indicating a possible transition of structure. The effect of alkyl chain length, electrolyte concentration, cosurfactant addition, and substrate on this concentration and the magnitude of the repulsive force demonstrates the similarities between the formation of these self-assembled surfactant surface structures and the formation and stability of bulk micelles.
Effect of clonidine and γ-Aminobutyric acid on the discharges of medullo-spinal sympathoexcitatory neurons in the rat

Single-unit recordings of 50 pressure-sensitive neurons with axonal projections to the thoracic spinal cord were obtained in the retrofacial portion of nucleus paragigantocellularis lateralis of halothane-anesthetized rats. Two types of cells were distinguished on the basis of their axonal conduction velocities: a slow-conducting (mean 0.6 m/s, group I) and a fast-conducting one (group II, mean 3.3 m/s). Both cell types were completely silenced by elevating mean arterial pressure above 160 mm Hg by means of aortic constriction and exhibited a plateau of high spontaneous activity below 70 mm Hg. Only group I neurons were significantly inhibited by the administration of clonidine in a dose producing 90% of its maximum hypotensive effect (11.5 g/kg, i.v.). Hypotensive doses of clonidine administered into the fourth ventricle also produced a selective inhibition of goup I neurons, while the others were unaffected. Iontophoretic applications of clonidine and norepinephrine produced an inhibition of the discharges of group I neurons qualitatively and quantitatively identical to that observed following administration of clonidine by the i.v. or i.c.v. route. Once more, group II cells were unaffected. In contrast, iontophoretically applied γ-aminobutyric acid exerted a powerful inhibition of both cell types, an effect which was totally prevented or reversed by the γ-aminobutyric acid antagonist bicuculline. Anatomical experiments were performed to uncover the potential source of catecholaminergic innervation of the area in which recordings were obtained. This area contains a large number of adrenaline-synthesizing neurons and receives a selective noradrenergic input from the A5 pontine group with no contribution from the A1, A2, A6 and A7 brainstem clusters of noradrenergic cells.
An intelligent web-based interface for programming content detection in q&a forums

In this demonstration, we introduce a novel web-based intelligent interface which automatically detects and highlights programming content (programming code and messages) in Q&A programming forums. We expect our interface helps enhancing visual presentation of such forum content and enhance effective participation.We solve this problem using several alternative approaches: a dictionary-based baseline method, a non-sequential Naive Bayes classification algorithm, and Conditional Random Fields (CRF) which is a sequential labeling framework. The best results are produced by CRF method with an F1-Score of 86.9%.We also experimentally validate how robust our classifier is by testing the constructed CRF model built on a C++ forum against a Python and a Java dataset. The results indicate the classifier works quite well across different domains.To demonstrate detection results, a web-based graphical user interface is developed that accepts a user input programming forum message and processes it using trained CRF model and then displays the programming content snippets in a different font to the user.
Transit Contracting Reexamined: Determinants of Cost Efficiency and Resource Allocation

National Transit Data from 1993 through 2004 is analyzed to examine the effects of contracting out on the cost efficiency and resource allocation of motor bus and demand response services. For motor bus service, results indicate no difference in cost between in-house and fully contracted operations. Contracting has a weak curvilinear association to total cost, suggesting that the most cost-efficient agencies either fully contract or they provide full in-house service. In contrast, demand response contracting is associated with about 20% lower total costs. Competitive conditions or the choice by agencies to offer specialized services may explain this result. Transit agencies that contract with multiple motor bus providers pay a cost premium, whereas multiple providers have no effect on demand response cost. Contracting does not affect the growth of cost for either service. An examination of expense subcategories reveals no reduction in administrative expenses when agencies contract services and only a partial reduction in nonoperational maintenance expenses. Overall, the results call into question the efficacy of competitive contracting models of transit service delivery and the use of fully allocated costing methods in make-versus-buy decisions.
Anion Affinity and Polarizing Power of Cations

IT is suggested that the ionization potential, I (first for univalent cations, second for divalent cations, third for trivalent cations, and so on), be used as a relative measure of the power of a cation to attract an anion (its ‘anion affinity’), and of its polarizing power. Its use thus may be demonstrated by some of the comparisons below. The general concept used here of the ability of cations to polarize and deform anions follows that discussed in the writings of Fajans1,2 and of others, and the homopolar bonds referred to below are regarded as strongly polarized ionic bonds.
AN EMPIRICAL COMPARISON OF METHODS FOR EQUATING WITH RANDOMLY EQUIVALENT GROUPS OF 50 TO 400 TEST TAKERS

A series of resampling studies investigated the accuracy of equating by four different methods in a random groups equating design with samples of 400, 200, 100, and 50 test takers taking each form. Six pairs of forms were constructed. Each pair was constructed by assigning items from an existing test taken by 9,000 or more test takers. The criterion equating was the direct equipercentile equating in the full group. Accuracy was described in terms of the root-mean-squared deviation (over 1,000 replications) of the sample equatings from the criterion equating. The equating methods investigated were equipercentile equating of smoothed distributions, linear equating, mean equating, and circle-arc equating; they were compared with each other and with the identity. Circle-arc equating produced the most accurate results for all sample sizes investigated, particularly in the upper half of the score distribution.
Presynaptic α7 Nicotinic Acetylcholine Receptors Enhance Hippocampal Mossy Fiber Glutamatergic Transmission via PKA Activation

Nicotinic acetylcholine receptors (nAChRs) are expressed widely in the CNS, and mediate both synaptic and perisynaptic activities of endogenous cholinergic inputs and pharmacological actions of exogenous compounds (e.g., nicotine and choline). Behavioral studies indicate that nicotine improves such cognitive functions as learning and memory. However, the mechanism of nicotine's action on cognitive function remains elusive. We performed patch-clamp recordings from hippocampal CA3 pyramidal neurons to determine the effect of nicotine on mossy fiber glutamatergic synaptic transmission. We found that nicotine in combination with NS1738, an α7 nAChR-positive allosteric modulator, strongly potentiated the amplitude of evoked EPSCs (eEPSCs), and reduced the EPSC paired-pulse ratio. The action of nicotine and NS1738 was mimicked by PNU-282987 (an α7 nAChR agonist), and was absent in α7 nAChR knock-out mice. These data indicate that activation of α7 nAChRs was both necessary and sufficient to enhance the amplitude of eEPSCs. BAPTA applied postsynaptically failed to block the action of nicotine and NS1738, suggesting again a presynaptic action of the α7 nAChRs. We also observed α7 nAChR-mediated calcium rises at mossy fiber giant terminals, indicating the presence of functional α7 nAChRs at presynaptic terminals. Furthermore, the addition of PNU-282987 enhanced action potential-dependent calcium transient at these terminals. Last, the potentiating effect of PNU-282987 on eEPSCs was abolished by inhibition of protein kinase A (PKA). Our findings indicate that activation of α7 nAChRs at presynaptic sites, via a mechanism involving PKA, plays a critical role in enhancing synaptic efficiency of hippocampal mossy fiber transmission.
Modelling and Control of Blackwater Treatment in Coal Preparation

Abstract Blackwater streams emerging as effluents from coal preparation plants typically contain considerable coal values which are rejected with waste solids. Additionally, new and proposed environmental regulations severely limit the use of coal refuse ponds and encourage closed water circuitry. Optimization of flotation cells and thickening units to overcome these limitations has not been successful in most cases. Models are chosen here for simulating the two processes and examined from a theoretical and practical standpoint in application to coal preparation problems. The emphasis of this analysis is to provide a rational basis for unit process control through proper model selection and application. Strengths and weaknesses of model approaches and developmental needs are also reviewed.
The proper motion VS redshift relation for superluminal radio sources

Two models for superluminal radio sources predict sharp lower bounds for the apparent velocities of separation. The light echo model predicts a minimum velocityv min=2c, and the dipole field model predictsv min=4.446c. Yahil (1979) has suggested that, if either of these models is correct, thenv min provides a ‘standard velocity’ which can be used to determine the cosmological parametersH andq 0. This is accomplished by estimating a lower envelope for the proper motion vs redshift relation. Yahil also argued that the procedure could easily be generalized to include a nonzero cosmical constant Λ. We derive the formulas relating the proper motion $$\dot \theta$$ to the redshiftz in a Friedmann universe with a nonzero Λ. We show that the determination of a lower envelope for a given sample of measured points $$(z_i ,\dot \theta _i )$$ yields an estimate of the angle of inclinationφ i for each source in the sample. We formulate the estimation of the lower envelope as a constrained maximum likelihood problem with the constraints specified by the expected value of the largest order statistic for the estimatedφ i . We solve this problem numerically using an off-the-shelf nonlinearly constrained nonlinear optimization program from the NAg library. Assuming Λ=0, we apply the estimation procedure to a sample of 27 sources with measured values $$(z_i ,\dot \theta _i )$$ , using both the light echo and the dipole field models. The fits giveH=103 km s−1 Mpc−1 for the light echo model andH=46 km s−1 Mpc−1 for the dipole field model. In both cases the fits giveq 0=0.4, but the uncertainty in this result is too large to rule out the possibility thatq 0>0.5. When Λ is allowed to be a free parameter, we obtainH=105 km s−1 Mpc−1 for the light echo model andH=47 km s−1 Mpc−1 for the dipole field model. In both cases the fits giveq 0=−1 and Λ/H 0 2 =6.7, but no significance can be attached to these results because of the paucity of measured data at hight redshifts. For all of the fits, we compute the corresponding estimates of theφ i and compare the cumulative distribution of these values with that expected from a sample of randomly oriented sources. In all cases we find a large excess of sources at low-inclination angles (high apparent velocities). The expected selection effect would produce such an excess, but the excess is large enough to suggest a strong contamination of the sample by relativistic beam sources which would only be seen at low inclination angles.
Promoting excellence in undergraduate mathematics through workshops based on collaborative learning

ABSTRACT Undergraduate mathematics plays a central and crucial role in our system of mathematics education. The goal in this article is to demonstrate, based on the Academic Mastery Program (AMP) at Occidental College, how to incorporate collaborative learning into the mathematics curriculum. AMP is a program that promotes achievement in mathematics by offering freshman undergraduates a collaborative learning environment that fosters success. It helps them to organize their lives around their academic interests. The structure of the program, we believe, minimizes the isolation of women, minorities, and borderline students by transforming each student's contribution into the success of a group. We will describe in detail the format of the weekly two hour workshops, which are supervised by student facilitators. Issues such as student recruitment, hiring facilitators, and designing worksheets will also be discussed.
Returning Refugees: Four Historical Patterns of 'Coming Home' to Rwanda

Over the 1990s, Western images of Africa became dominated by a social landscape of mobile people fleeing disaster. In the aftermath of the horrendous 1994 genocide in Rwanda, refugees and IDPs (“internally displaced people,” the term used for uprooted individuals within a state) were especially visible in Central Africa, but West Africa also was the locus of a series of complicated refugee movements (from Liberia, Sierra Leone, Guinea, Cote d'Ivoire, and elsewhere), and northeast Africa (Sudan, Ethiopia, Eritrea, Somalia) generated many more. Such flight from fear, however, was not new to Africa. Many people had fled colonial extractions or had been forcibly moved for purposes of colonial labor; many more were caught up in precolonial relocations. Of course many were forcibly moved as well in the massive displacement of slaves from and within Africa, and voluntary movement was also common, for land, trade, or religious duty. Consequently, while in the West, Africa is often thought of as a continent in stasis, with the rural poor tied to their land, in fact, the historical record indicates that Africa has always been a continent of enormous mobility.