cssi/SciSciGPT-SciSciNet huggingface dataset:
Statistical Analysis and Compound Selection of Combinatorial Libraries for Soluble Epoxide Hydrolase

Inhibitors of soluble epoxide hydrolase (sEH) have been extensively pursued as antihypertensive therapies as well as potential treatment for other cardiovascular dysfunctions and prevention of renal damage. In this study we report quantitative structure–activity relationship (QSAR) models for 1223 structurally diverse sEH inhibitors produced by combinatorial library design and synthesis. Daylight fingerprints, MOE 2D and DragonX descriptors were generated for QSAR modeling approaches. Using these descriptors, a number of statistical models were trained and validated. Of these methods, gradient boosting machines (GBM), partial least-squares (PLS), and Cubist methods demonstrated the best performance on training and test set validation in terms of their leave-group-out cross-validated (LGO–CV) Q2 and correlation coefficient R2 (Q2GBM-training = 0.79, R2GBM-test = 0.81; Q2PLS-training = 0.75, R2PLS-test = 0.75; Q2Cubist-training = 0.91, R2Cubist-test = 0.78). A final model was constructed using the consensus...
Different regions of a complex satellite DNA vary in size and sequence of the repeating unit

Abstract The 1.688 g/cm 3 satellite DNA of Drosophila melanogaster is composed primarily of 359 base-pair units repeated in tandem. Most of these units contain a single cleavage site for both Hae III and Hin fI restriction endonucleases; however, some units lack one or both sites. Previously we had shown that the distribution of Hae III and Hin fI endonuclease sites varies widely between different regions of 1.688 g/cm 3 satellite DNA; for example, some regions contain Hae III sites in every unit and other regions (>10,000 base-pairs) contain no Hae III sites (Carlson & Brutlag, 1977). We have now cloned molecules of 1.688 g/cm 3 satellite DNA which lack Hae III sites and have shown that the absence of sites is caused by sequence variation rather than base modification. This result indicates that regions of 1.688 g/cm 3 satellite DNA with different distributions of restriction sites differ in the sequence of their repeating units. We also show that a large fraction of the satellite DNA which is not cleaved by Hae III endonuclease still contains Hin fI endonuclease sites (and Alu I sites) spaced about 359 base-pairs apart. However, one cloned segment lacking Hae III sites was found to contain 33 tandem copies of a novel 254 base-pair unit. Sequence analysis showed that this 254 base-pair unit is homologous to the 359 repeat except for a 98 base-pair deletion. These data suggest that both units have evolved from a common ancestor and that each has subsequently become amplified into separate tandem arrays.
13-cis-retinoic acid for dyskeratinizing diseases--clinicopathological responses.

Summary Fifteen patients with Darier's disease (five patients), epidermolytic hyperkeratosis (five patients), and pityriasis rubra pilaris (five patients) were treated with doses ranging from 1.0 to 3.0 mg per kg body weight of 13 -cis retinoic acid. There was marked clinical improvement in the patients with Darier's disease which was sustained in two out of five on stopping treatment after 6 months. Three patients with pityriasis rubra pilaris went into remission, and required no further treatment on stopping 13-cis retinoic acid after 6 months; however two patients did not respond at all. All five patients with epidermolytic hyperkeratosis responded, but relapsed rapidly on discontinuation of therapy. The major histological change noted was the reduction in stratum corneum organisation and cohesion, with reduction in stratum corneum layers. Serum cholesterol and triglycerides became raised after 1 month's therapy, but tended to fall during the following 5 months of therapy. High density lipoproteins remained depressed during treatment. In selected cases, 13-cis retinoic acid is a useful therapy for Darier's disease, pityriasis rubra pilaris and epidermolytic hyperkeratosis.
Inhibition of chemically induced erythrodifferentiation in friends erythroleukemia cells by d,1-Propranolol☆

Abstract Dimethyl sulfoxide (2%), hexamethylene bisacetamide (4mM) and butyric acid (2mM) were potent inducers of erythrodifferentiation in Friend erythroleukemia cell lines, 5–18 and C19TK. Hydrocortisone (1μM) markedly inhibited dimethyl sulfoxide induced hemoglobin production in both 5–18 and C19TK cells. d,1-Propranolol (25–50μM) markedly inhibited both dimethyl sulfoxide and hexamethylene bisacetamide induced erythrodifferentiation in 5–18 cells but not in C19TK cells. Addition of either hydrocortisone or propranolol as late as 48 hrs after dimethyl sulfoxide addition still resulted in significant inhibition of hemoglobin synthesis in 5–18 cells. Although the mechanism of action of propranolol is not known, modulation of the β adrenergic receptor is apparently not involved since practolol failed to inhibit either dimethyl sulfoxide or hexamethylene bisacetamide induced erythrodifferentiation in 5–18 cells nor did isoproternol induce hemoglobin synthesis.
Can technical change exacerbate the effects of labor market sclerosis

Abstract This paper constructs a general equilibrium model with technology adoption, in which labor reallocation is determined by the rate of embodied technical change (ETC) and by labor market rigidities. In the calibrated model, ETC has a positive effect on aggregate employment, but this effect is weaker in the presence of firing costs. As a result, a higher rate of ETC generates a modest increase in the divergence of employment outcomes across countries that have different levels of institutional firing costs. Central to this result is the link between adoption costs and the rate of embodied technical change. The importance of entry costs and skill requirements is also explored.
Nitrogen Limitation of Pond Ecosystems on the Plains of Eastern Colorado

Primary production in freshwater ecosystems is often limited by the availability of phosphorus (P), nitrogen (N), or a combination of both (NP co-limitation). While N fixation via heterocystous cyanobacteria can supply additional N, no comparable mechanism for P exists; hence P is commonly considered to be the predominant and ultimate limiting nutrient in freshwater ecosystems. However, N limitation can be maintained if P is supplied in stoichiometric excess of N (including N fixation). The main objective of this study was to examine patterns in nutrient limitation across a series of 21 vernal ponds in Eastern Colorado where high P fluxes are common. Across all ponds, water column dissolved inorganic N steadily decreased throughout the growth season due to biological demand while total dissolved P remained stable. The water column dissolved inorganic N to total dissolved P ratios suggested a transition from NP co-limitation to N limitation across the growth season. Periphyton and phytoplankton %C was strongly correlated with %N while %P was assimilated in excess of %N and %C in many ponds. Similarly, in nutrient addition bottle assays algae responded more strongly to N additions (11 out of 18 water bodies) than P additions (2 out of 18 water bodies) and responded most strongly when N and P were added in concert (12 out of 18 water bodies). Of the ponds that responded to nutrient addition, 92% exhibited some sort of N limitation while less than 8% were limited by P alone. Despite multiple lines of evidence for N limitation or NP co-limitation, N fixation rates were uniformly low across most ponds, most likely due to inhibition by water column nitrate. Within this set of 18 water bodies, N limitation or NP co-limitation is widespread due to the combination high anthropogenic P inputs and constrained N fixation rates.
A new positron source with high flux and excellent electron-optical properties

Abstract Positron annihilation spectroscopy is a well established research tool to study the surface and bulk electron distributions of solids and liquids. These are extracted from the energy and angular distributions of the two 511 keV X-rays, produced during the annihilation of a thermal positron and an electron from the sample. Positron investigations and monitoring, however are currently not used in an industrial environment due to the lack of a sufficiently intense positron sources to record distribution functions with good statistics within minutes. Most positron spectrometers have radioactive sources which produce only modest intensities (106 e+/s). An improvement by at least a factor of 100 is needed to become viable for on-line positron metrology. We propose to combine several technologies to generate a positron beam with good electron-optical properties, such as a small divergence angle and small beam diameter and a flux of 108 e+/s or more. Positrons from a 10 Ci beta source will be moderated with a stack of 12 layers of tungsten meshes. The thermalized positrons will be accelerated into a deflection focusing analyzer (DFA) which focuses the positrons into a small (1–2 mm2) area of a second moderator. A rare gas solid will be used to thermalize the positrons once more. The moderating area forms the small emitter source for a accelerating gun that generate a beam of mono-energetic positrons of any desired energy.
Relationship between fundamental interfacial properties and foaming in linear and branched sulfate, ethoxysulfate, and ethoxylate surfactants

Abstract The effect of hydrocarbon chain branching on the foaming performance of a variety of sulfate, ethoxysulfate, and ethoxylate surfactants was determined by the Ross—Miles test. Data from static and dynamic surface tension experiments were used to obtain a structure—property—performance correlation. Initial foam heights correlated with π (CMC), the effectiveness of surface tension reduction, while foam instability correlated with R 1 2 , the rate of surface tension reduction at the air—water interface. Hydrocarbon chain branching resulted in increased π (CMC) and R 1 2 . Consequently, surfactants wherein the hydrocarbon chain is branched exhibited high initial foam heights and low foam stability.
The importance of leadership diversity: The relationship between diversity and organizational success in the academic environment

In the academic community, efforts to foster diversity are generally supported by a rationale that relates to equity and changing societal demographics. Private sector research, however, indicates support for a rationale relating to overall organizational success. Such research forms the basis for the consideration of the relationship between diversity and organizational success in the academic environment. In addition, the research provides evidence that diversity continues to be valued in the private sector, which employs many of the graduates whose academic preparation is supported by the college or university library. This article presents the results of a research study involving diversity and organizational success in the academic environment. The results provide evidence that there is a relationship between diversity and organizational success and offers further support for the results of the prior research in this area, as well as offering data to enhance the rationale for the support of diversity efforts in the academic library community.
Reducing the size of the nondominated set: Pruning by clustering

The multicriterion simplex methods of Evans and Steuer [1] and Yu and Zeleny[2] have encouraged model builders to consider matrix criteria. When conflicting objectives are simultaneously considered, there is no such thing as an optimum solution. Rather, a preferred class of basic feasible solutions called the nondominated set results. Since this set can be extremely large, some means must be found to prune it. Steuer [3] has proposed a filtering method. Another mechanistic aid to the decision maker (DM), based on cluster analysis, is presented in this paper. The idea is to portray the nondominated set N by a representative subset. Cluster analysis partitions N into groups of relatively homogeneous elements. In this research I added a very general evaluative criterion: minimum redundancy. Since there is a threshold of resolution beyond which the DM cannot perceive the difference between two very similar solution vectors, there is little point in making him waste time processing all of N in the search for a final solution. Two forms of cluster analysis are tested-direct clustering and hierarchical clustering. Within the group of hierarchical methods there are eight algorithms. In the present application the two worst things that could happen are clusters that “chain” and outlying vectors (the residue set) that are obscured. Taking account of these two undesirable outcomes, three algorithms worked best on the particular data used-Ward's Method, the Group Average Method and the Centroid Method. The hierarchical methods are recommended over direct clustering. (However, some similarity between direct and hierarchical clustering is discovered.) Hierarchical clustering serves to minimize redundancy and thereby reduces the chance that the selection of a final solution will stress the decision maker beyond his information endurance. The concepts stressed in this paper are very similar to those expressed in Torn [4]. This article presents computational experience with the cluster analysis which was developed independently by Torn, whose approach and mine will be combined under an algorithmic strategy called Two-Stage Pruning (TSP). TSP first reduces the nondominated set to a representative set. This set, in turn, is interactively manipulated until a decision evolves.
Computation of Jn(x) by numerical integration

It is shown to be practical to compute Jn(x) by numerical integration of its integral representation using the trapezoidal rule. The error in this approximation was studied empirically.
Ontogenetic, intraspecific, and interspecific variation of the prehallux in primates: Implications for its utility in the assessment of phylogeny

The prehallux is a sesamoid bone occurring in the region of the hallucial tarso-metatarsal joint in a number of metatherian and eutherian orders and in some nonmammalian tetrapods. Within the order Primates, it occurs invariably in ceboids and Hylobates, with extreme infrequency in pongids and Homo, and is absent in other primates groups. It has been suggested that, first, the prehallux is homologous both within and across the infraclasses Metatheria and Eutheria; second, it has functional significance in that it contributes to joint stability and is an adaptation to arboreality; third, its presence results in diagnostic features on the entocuneiform and hallucial metatarsal, so that original presence or absence can be unambiguously assessed in instances when the bone itself is not preserved; and fourth, because of presumed homology, it may be employed in the reconstruction of phylogenetic relationships. The present study concludes that the homologous nature of the bone is open to reasonable doubt, the assumption of homology does not yield significantly more parsimonious phylogeny reconstructions than does the assumption of analogy, there are no invariant diagnostic features associated with its presence, and functional explanations currently offered are of questionable validity. Thus, the prehallux is at present of little utility in either establishing or precluding phylogenetic relationships among primates.
Species differences and the role of sodium-calcium exchange in cardiac muscle relaxation

During normal relaxation in rabbit, guinea-pig, and rat ventricular muscle, the Na-Ca exchange system competes with the SR Ca pump, with the former being responsible for about 20-30% of the Ca removal from the cytoplasm. Ca extrusion via Na-Ca exchange is Em-sensitive, whereas Ca uptake by the SR is not. Neither the sarcolemmal Ca-ATPase pump nor mitochondrial Ca uptake appear to contribute significantly to the decline of [Ca]i during relaxation. Furthermore, the diastolic efflux of Ca from cardiac muscle cells appears to be primarily attributable to Na-Ca exchange and not the sarcolemmal Ca-ATPase pump. In rabbit ventricle Ca entry via Na-Ca exchange is favored thermodynamically during much of a normal twitch contraction and Ca extrusion occurs primarily between beats. In rat ventricle Ca efflux via Na-Ca exchange occurs during the contraction and net Ca influx may occur between beats. This fundamental difference in Ca fluxes during the cardiac cycle in rat versus rabbit ventricle may be a simple consequence of the shorter action potential duration and higher aNai in rat ventricle (due to the effects of Em and [Na] and [Ca] gradients on Na-Ca exchange).
Increasing students' choice‐making consistency: The effect of decision rule‐use training

The present study examined the extent to which the inability to translate decisionally revelant information into matrix form and knowledge about decision rule use act as impediments to consistent choice‐making. Participants were provided with five decision making cases in written paragraph form and no instruction, five decision making cases accompanied by the data in matrix form and no instruction, the paragraph form cases and one hour of instruction including the selection and calculation of decision rules or matrix information and instruction. Results indicate that instruction, in decision matrix construction and decision rule application, increases students' decision making consistency. The advisability of advocating particular rules and the merits of consistency are discussed.
New Treatment for Patients With Short-Bowel Syndrome: Growth Hormone, Glutamine and a Modified Diet T. A. BYRNE, R. L. PERSINGER, L. S. YOUNG, ET AL Ann Surg 222.-243-255, 1995

After massive enterectomy, the remnant bowel must undergo both morphologic and physiologic adaptation if the patient is to wean to volitional enteral support. Those patients who are unable to adapt require long-term total parenteral nutrition (TPN) with its concomitant high cost and metabolic anomalies. Previously, it was believed that adaptation ceased after a period of 1 to 2 years. In 1992, Byrne et al presented the theory that further adaptation could be elicited in a group of 8 patients who had been on TPN for up to 6 years by treatment with a combination of growth hormone, free glutamine, and a diet high in fiber and low in fat. 1 This paper did not delineate the specific mechanisms or present long-term results. The current study involves 47 patients with short-bowel syndrome dependent on TPN for an average of 6 years. Average age was 46 with a mean jejunoileal length of 50 ± 7 cm. Half of the patients had <35 cm of small bowel. Etiologies included volvulus, SMA thromboses, or adhesions in the vast ...
Graphics techniques in concurrent simulation

This paper discusses work occurring in the hypercube simulation laboratory and visualization schemes for concurrent simulation. The principle contribution of this work is that of a cost effective technical approach to simulation visualization. This approach is being replicated and applied to contemporary large scale simulation problems of interest around the country.Since the hypercube graphics interface is a working prototype there is a mix of practice and experience along with novel approaches to contemporary graphics problems. A discussion of techniques which accelerated graphics development is included. Among these are issues of interpreted vs. compiled tools for simulation visualization and supercomputer-display interface methodology. A survey of other significant efforts in combining hypercubes and graphics is provided. Finally the issue of interactive simulation exploration via real time displays is discussed with an eye toward the future.
Retrieval practice and testing improve memory in older adults

Background: Older adults have difficulty remembering detailed information from what they have read, despite maintaining relatively well preserved gist-level processing. However, an over-reliance on gist can result in vague and errorful encoding. Retrieval-based strategies using testing via free recall have been shown to be more effective for long-term memory retention of text details than additional study, a phenomenon known as the “testing effect”. Retrieval is thought to act as a secondary encoding, thus strengthening memory. Older adults would benefit then, from retrieval-based memory strategies that train efficient encoding of text information. These strategies to enhance memory in older adults can inform evidence-based treatment approaches for adults with acquired neurogenic communication disorders.Aims: The current study’s first aim was to compare the effects of two training techniques in healthy older adults for remembering details of unfamiliar expository texts: (1) Read Attentively, Summarise and...
The cell of origin of ovarian epithelial tumours

Summary Although it is widely believed that ovarian epithelial tumours arise in the coelomic epithelium that covers the ovarian surface, it has been suggested that they could instead arise from tissues that are embryologically derived from the Mullerian ducts. This article revisits this debate by discussing recent epidemiological and molecular biological findings as well as evidence based on histopathological observations of surgical specimens from individuals with familial ovarian cancer predisposition. Morphological, embryological, and molecular biological characteristics of ovarian epithelial tumours that must be accounted for in formulating a theory about their cell of origin are reviewed, followed by comments about the ability of these two hypotheses to account for each of these characteristics. An argument is made that primary ovarian epithelial tumours, fallopian tube carcinomas, and primary peritoneal carcinomas are all Mullerian in nature and could therefore be regarded as a single disease entity. Although a substantial proportion of cancers currently regarded as of primary ovarian origin arise in the fimbriated end of the fallopian tube, this site cannot account for all of these tumours, some of which are most likely derived from components of the secondary Mullerian system.
The Effects of Surface Films in Damping Eddies at a Free Surface of a Turbulent Liquid

Mass-transfer rates across a gas liquid surface into a turbulent liquid depend markedly on the hydrodynamic behaviour of the liquid immediately subjacent to the interface. Though turbulence is always somewhat damped at a free liquid surface, there may remain significant movements of liquid into the plane of a clean surface. A very small amount of surface-active material, however, sets up gradients of surface tension between different parts of the surface, and the accompanying (elastic) stresses are shown to damp very strongly eddies approaching the surface, thus reducing the rate of ‘surface renewal’: mass-transfer of a solute across the liquid surface is correspondingly retarded. This paper treats these phenomena quantitatively, and includes five predictions of the effects of surface-active agents. Comparison is made with published experimental data.
Scanning tunneling microscopy of SiGe alloy surfaces grown on Si(100) by molecular beam epitaxy

Abstract An investigation into the surface structure and morphology that results from the growth of SiGe alloys with 0%, 5%, 10%, and 20% Ge bulk concentration at 500 and 800 °C on Si(1 0 0) is presented. Stages of alloy growth are reported from the initial Si–Ge intermixing to the segregation of Ge from the alloy to the final 2D island surface morphology. Surface Ge produces a “2× n ” surface reconstruction, which is shown to result from a mixture of local atomic orderings of c(4×2) and p(2×2) that varies with alloy concentration. The alloy surfaces are characterized by 2D island growth, where the surface roughness is observed to increase with increasing Ge concentration and with increasing growth temperature. A discussion of the effects of adatom mobility, compressive strain, step-edge attachment, and surface reconstruction involved in 2D island growth are presented.
Racial disparity in cardiac decision making: results from patient focus groups.

Background While numerous studies suggest that African Americans receive fewer invasive cardiac procedures than whites, the basis for these treatment differences is not understood. Methods We conducted focus group sessions with patients who had received treatment in the hospital or the emergency department within the preceding 3 months for ischemic heart disease at 2 urban, university-affiliated hospitals. Results Discussions with patients identified the following factors that influenced their decision making: clarity, simplicity, and consistency of treatment recommendations; advice from friends and family about whether to accept recommendations; availability to speak with others who accepted similar recommendations; and having honest and caring physicians. African American patients identified the following additional factors that influenced their decision making: perceptions of health care discrimination; perceptions of undesirable physician behavior; faith in God to control one's destiny; and patient-physician camaraderie. Conclusions Participants identified common issues influencing health care decision making, regardless of race. However, additional factors were expressed only by African American participants. These factors conveyed racial differences in perceptions of the health care system that may, in part, contribute to differences in health care decision making and treatment.
Separation of spatial and temporal structure of auroral particle precipitation

[1] Knowledge of the dominant temporal and spatial scales of auroral features is instrumental in understanding the various mechanisms responsible for auroral particle precipitation. Single spacecraft data always suffer from temporal/spatial ambiguity. In an effort to separate the temporal and spatial variations of the aurora, we use electron and ion precipitation data from two co-orbiting satellites, F6 and F8 of the Defense Meteorological Satellite Program (DMSP). The two spacecraft have almost identical polar orbits with a small difference in period. As a result the time difference between the two measurements varies with time. We use two statistical tools in order to determine the most probable lifetimes and spatial dimensions of the prevalent auroral features. The first tool is cross-correlation analysis between the magnetic latitude series of electron and ion, number and energy fluxes measured by the two DMSP spacecraft. As one spacecraft overtakes the other, the variable time lag between the two measurements results in different cross-correlation of the two series. We explore the dependence of this variation on the time lag between the satellites. We find that the electron precipitation exhibits a decreasing correlation between the two spacecraft with increasing time lag, whereas there is only a small similar effect for the ion precipitation data. The second statistical tool is cross-spectral analysis, for which we compute the so-called coherence function as a function of frequency (or inverse wavelength) and hence size of the auroral features. The coherence function is a measure of the stability of auroral features of different sizes. We investigate its variation as a function of the time separation between the two measurements. We show that the coherence function of both electrons and ions remains high for up to 1.5 min spacecraft separations for all features larger than about 100 km in width. For smaller features the coherence is lower even for time lags of a few seconds. The results are discussed in the context of characteristic temporal and spatial auroral scales deduced from complementary studies and expected from theory.
Walking the tightrope: Using quantitative Doppler echocardiography to optimize ventricular filling pressures in patients hospitalized for acute heart failure

Acutely decompensated heart failure (HF), one of the most common reasons for hospitalization, places an intense economic pressure on the health care system and adversely affects outcome of HF patie...
Sensing Difference: Whiteness, National Identity, and Belonging in the Dominican Republic

This article examines local conversations and practice of using the senses—sight, smell, taste, touch and hearing—to detect difference and establish belonging and non-belonging on streets and private spaces in the Dominican Republic. The physiological capacity for Dominicans to sense difference is culturally and politically filled by national, regional, and often under researched local understandings and practices that attempt to define “ambiguous notions of” national identity and whiteness. Drawing on 10 years of ethnographic data and personal encounters in the field and situating them within Post-September 2013 Constitutional Court ruling, I argue that through an examinations of these moments of negotiable belonging a nuanced understanding of Dominican national identity and its relation to whiteness, race, class, and gender emerges, one that goes beyond questions of citizenship rights and civil duty—matters that lie within the state and its institutions—to encounters in the streets among individuals whose actions at times consolidate and naturalize state power and national discourse, and at other times, contradict and challenge it.
SOME FINE STRUCTURAL OBSERVATIONS ON DEVELOPING AND MATURE SIEVE ELEMENTS IN THE BROWN ALGA LAMINARIA SACCHARINA

A B S T R A C T The differentiation of sieve elemenits from inner cortical cells of the stipe of Laminaria saccharina (L.) Lamour. involves the development of a well-structured protoplast and an end wall possessing evenly spaced pores which are visualized by electron microscopy. The protoplast consists of organelles which are commonly found in brown algal cells, including nuclei, cup- or horseshoe-shaped chloroplasts, dictyosomes, mitochondria, and ER. Mitochondria and clusters of small vacuoles, presmfnably redistributed by the surging effect which occurs in sieve elements, were routinely observed in the vicinity of the end wall. Chloroplasts were seen in progressively degenerated states in older sieve elements, yet nuclei were determined to be nonnecrotic. Nurnerous pores along the end walls interconnect adjacent sieve elements. Each pore is traversed by a strand of cytoplasm and surrounded by plasmalemma. The pores are open and possess no callose. In this paper the sieve element ultrastructures of L. saccharina are compared to those in L. groenlandica, Alaria marginata, Nereocystis lutkeana and Macrocystis p)yrifera, and a possible phylogenetic specialization of sieve elements is presented in table form and discussed.
Design and characterization of pentacene–inorganic interfaces

Abstract The accumulation layer of organic thin film field-effect transistors extends away from the gate insulator/semiconductor interface by only a few molecular layers into the semiconductor thin film. The structure of these first few layers are thus crucially important to the electrical properties of devices and to the design of other functional structures incorporating organic/inorganic interfaces. We have used scanning tunneling microscopy to image the vacancies and grain boundaries in pentacene thin films on Si (0 0 1) substrates chemically terminated by styrene. The styrene termination allows pentacene molecules to form in a crystal structure similar to that of pentacene layers on the insulating substrates. In addition, by incorporating specially designed molecular monolayers at the interface between the gate insulator and the pentacene thin film, it is possible to form novel photoinduced charge-transfer structures. Tuning the chemical properties of the self-assembled monolayers affords a new degree of control in tuning the properties of these devices.
Conducting meta-analyses of HIV prevention literatures from a theory-testing perspective.

Using illustrations from HIV prevention research, the current article advocates approaching meta-analysis as a theory-testing scientific method rather than as merely a set of rules for quantitative...
Approximate characterization of multi-robot swarm “shapes” in sublinear-time

Many envisioned applications of multi-robot swarms involve the detection, production or maintenance of global structures through only local means. This paper introduces a scalable, distributed algorithm to approximately characterize important global geometric and topological properties. For a given spatial arrangement of robots, the algorithm estimates the longest network (geodesic) distance in any direction as well as the average Euclidean distance only using locally sensed information. In so doing, the robots need only to communicate with and sense (range and bearing) nearby robots. The algorithm uses a greedy method to approximate both distance metrics via parallel one-way message traversals. We provide a bound for the number of such traversals, showing a global characterization is produced in a running time that is sublinear in the total number of robots. Along with this analysis, we conduct simulations with hundreds of robots to validate the algorithm.
A Tetrad Analysis of the Basidiomycete Fungus Cryptococcus neoformans

Cryptococcus neoformans is a basidiomycete fungus that is found worldwide and causes disease in humans and animal species. The fungus grows asexually as a budding yeast. Under laboratory conditions it is capable of sexual reproduction between two mating types. After cell fusion a dikaryotic filament develops, at the tip of which a basidium gives rise to four chains of basidiospores. Because the chains each comprise 10-30 spores, rather than single spores, the analysis of individual meiotic events has not been attempted in C. neoformans in the style of tetrad analyses performed in other fungal species. Here, the basidiospores from >100 basidia were micromanipulated and the resultant >2500 progeny analyzed for three genetic markers to understand the sexual process in this fungus, leading to four observations: (i) Marker segregation provides genetic evidence for a single meiotic event within the basidium followed by multiple rounds of mitosis. (ii) Using each basidium as an unordered tetrad, the ADE2 and URA5 genes are linked to their centromeres, consistent with adjacent genomic regions rich in repetitive elements predicted to comprise Cryptococcus centromeres. (iii) Lack of germination of basidiospores is attributed to aneuploidy, rather than dormancy. (iv) Analysis of basidiospores derived from single chains demonstrates that each chain can contain different genotypes. This mechanism of sexual spore production would benefit the species with a high rate of dispersal and at the same time aid in simultaneous dissemination of both mating types to new locations in the environment.
Numerical simulations of a relativistic magnetron

A two-dimensional particle-in-cell (PIC) simulation is used to study the self-consistent evolution of the space-charge cloud in a high-power magnetron. In the simulation, a rotating reference frame reduces the field solution to an inversion of Poisson's equation, which is solved in a cylindrical geometry. The particles are moved relativistically. The simulation is applied to the A6 magnetron, which is the prototype for the new class of relativistic magnetrons. Good agreement is found with published experimental results. The simulation is used to study the effect of power extraction on efficiency, the role of the wave magnetic field on saturation, and relativistic effects of magnetron operation. Interaction regions within the charge cloud are identified. >
Evolved patterns and rates of water loss and ion regulation in laboratory-selected populations of Drosophila melanogaster.

We have investigated water loss from, and ion regulation within, the hemolymph and tissues of five replicate populations of Drosophila melanogaster that have undergone laboratory selection for enhanced desiccation resistance (i.e. the D populations). We compared the patterns and rates of water loss and the ion content of the D populations prior to and during desiccation with those of five replicate control (C) populations. The net rate of water loss in the C flies was ∼3-fold greater than that of the D flies during the initial hours of desiccation. After 8 h, both C and D flies had considerable reductions in water loss rate. During 24 h of desiccation, the tissue water content of the D flies was conserved, while the C flies were faced with significant loss of tissue water during the initial 8 h of desiccation. We propose that the increased hemolymph volume of the D flies plays a role in buffering water loss from the tissues. One consequence of this large hemolymph pool is that the hydrated D flies contained approximately seven times more sodium within the hemolymph than did the hydrated C flies. Despite a continual loss of hemolymph volume in the D flies during lengthy periods of desiccation, the sodium content of the hemolymph was significantly reduced only during a single event. We provide evidence that the regulation of extracellular sodium, as well as chloride, occurred via excretory processes during desiccation. In addition, whole-body potassium was not significantly decreased in the D flies during desiccation but was reduced (i.e. excreted) in the C flies; hence, we suggest that the potassium content paralleled tissue water level.
The radical constructivist view of science

From the constructivist perspective, science cannot transcend thedomain of experience. Scientific theories are seen as models that helpto order and manage that domain. As the experiential field expands,models are replaced by others based on novel conceptual constructs. Thepaper suggests the substitution of ‘viability’ or ‘functional fit’ forthe notions of Truth and objective representation of anexperiencer-independent reality. This by-passes the sceptics'incontrovertible arguments against certain real-world knowledge andproposes the Piagetian conception of cognition as the function thatgenerates ways and means for dealing with the world of experience.
Transcatheter Intraarterial Infusion of rt-PA for Acute Lower Limb Ischemia: Results and Complications

PURPOSE To determine the success and complication rates of intraarterial recombinant tissue-type plasminogen activator (rt-PA) infusion for the treatment of acute lower extremity artery and bypass graft occlusions. MATERIALS AND METHODS The results of 74 limbs in 70 patients (mean age, 66 y) treated with catheter-directed rt-PA infusion for the treatment of acute lower extremity ischemia were retrospectively evaluated. The group included 42 bypass grafts and 32 native arteries. All limbs were viable at presentation. The mean duration of symptoms was 11.9 days. rt-PA was infused for a mean of 27.9 hours for a mean total dose of 38.7 mg. Initial infusion rates of 3–6 mg/h were lowered to a preferred rate of 1.5 mg/h. Thrombolytic success was defined as 95% thrombolysis of an occluded segment with return of antegrade flow. Major bleeding complications were defined as any hemorrhagic event leading to surgery, extended or unexpected hospitalization, transfusion, death, intracranial hemorrhage, or a decrease in hemoglobin of 5 g/dL or in hematocrit of 15%. Thirty-day mortality and amputation rates were calculated. Patient characteristics and infusion parameters were evaluated as to whether they contributed to thrombolytic success or major bleeding events. RESULTS Thrombolytic success was achieved in 64 limbs (86%). Major bleeding complications occurred in 33 (47%) patients. In 22 of these patients, bleeding occurred at a vascular puncture site, whereas remote bleeding occurred in seven patients. Remote bleeding complications included two retroperitoneal hematomas, two rectus sheath hematomas, one lower gastrointestinal hemorrhage, one episode of hemoptysis, and one dehiscence of a femoral-popliteal bypass graft revision. No parameters were found to be predictive of thrombolytic success, whereas a negative history of smoking, increasing duration of infusion, and a low preprocedural ankle-brachial index (ABI) were found to be associated with major hemorrhagic events. Four patients (6%) underwent amputation and one patient (1%) died, resulting in a 30-day amputation-free survival rate of 93%. CONCLUSION Catheter-directed rt-PA infusion is effective in achieving thrombolysis. Despite a significant number of bleeding complications, 30-day mortality and amputation rates were favorable. Nonetheless, complication rates related to bleeding were not trivial and further evaluation with use of variable dosing regimens is indicated.
The myth of the L.D. WISC‐R profile

Abstract One frequently finds researchers and practitioners attempting to identify subtest scoring patterns on the Wechsler Intelligence Scales indicative of learning disabilities. This review notes the many statistical and research design flaws in these studies. In conclusion, the point is made that extant research has not been able to confirm an L.D. pattern and that, probably, the search for an L.D. profile is no longer justified.
Expression profiling of BEN regulated genes in mouse embryonic fibroblasts

BEN is a member of the TFII-I family of helix–loop–helix transcription factors. Both TFII-I and BEN are involved in gene regulation through interactions with tissue-specific transcription factors and chromatin remodeling complexes. Identification of the downstream target genes of TFII-I proteins is critical in delineating the regulatory effects of these proteins. In this study, we conducted a microarray analysis to determine gene expression alterations following the overexpression of BEN in primary mouse embryonic fibroblasts (MEFs). We found the BEN-dependent modulation in the expression of large groups of genes representing a wide variety of functional categories including genes important in the immune response, cell cycle, transcriptional regulation and cell signaling. A set of genes identified by the microarray analysis was validated by independent real-time PCR analysis. Among upregulated genes were Shrm, Tgfb2, Ube2l6, G1p2, Ccl7 while downregulated genes were Folr1, Tgfbr2, Csrp2, and Dlk1. These results support a versatile function of TFII-I proteins in vertebrate physiology and lead to an increased understanding of the BEN-dependent molecular events. J. Exp. Zool. (Mol. Dev. Evol.) 308B:209–224, 2007. © 2006 Wiley-Liss, Inc.
Evaluation of predictors of clinical outcome after partial left ventriculectomy.

Abstract Background . Outcome after partial left ventriculectomy (PLV) is difficult to predict. Our goal was to determine if clinical measurements including exercise testing could predict outcome after PLV. Methods . Sixteen patients with dilated cardiomyopathy had left ventricular ejection fraction, left ventricular end-diastolic diameter, amount of mitral regurgitation (MR), New York Heart Association (NYHA) functional class, and cardiopulmonary exercise testing measurements measured before PLV and 3 months after PLV. Eleven patients who remained stable after PLV (group 1) were compared with 5 patients who deteriorated after PLV (group 2). Results . Similar significant improvements were seen in both groups 3 months post-PLV with respect to left ventricular ejection fraction (group 1: 0.136 ± 0.037 to 0.212 ± 0.046; group 2: 0.139 ± 0.042 to 0.179 ± 0.073) and left ventricular end-diastolic diameter (group 1: 8.5 ± 0.7 to 7.0 ± 0.6 cm; group 2: 7.6 ± 0.6 to 6.5 ± 0.6 cm). The MR grade (1.0 ± 0.6 versus 2.5 ± 0.6), NYHA functional class (1.5 ± 0.31 versus 2.5 ± 0.6), and peak oxygen consumption (17.8 ± 1.1 versus 12.2 ± 2.0) were significantly different in the two groups 3 months after PLV ( p Conclusions . Patients that do not show significant improvement in peak oxygen consumption, NYHA class and significant decrease in the amount of MR 3 months after PLV, compared with pre-PLV, are at increased risk of clinically deteriorating.
Investigating the Binding of Acridine, Acridine Orange, and Acridine Yellow G to Humic Acid Through Fluorescence Quenching

A fluorescence quenching method was used to determine the equilibrium binding constants for the association of acridine, acridine orange, and acridine yellow G to humic acid. The fluorescence of each polycyclic aromatic nitrogen heterocycle (PANH) was monitored as aliquots of humic acid were added, and a Stern-Volmer plot was produced in which the slope is the equilibrium constant of the binding reaction. The quenching experiments were performed at temperatures of 30, 35, 40, and 45 °C. A van't Hoff plot generated from the equilibrium binding constants as a function of temperature for a given PANH resulted in a linear plot. Calculation of the ?Hbinding, ?Gbinding, and ?Sbinding for each PANH leads to the conclusion that the equilibrium binding constant, and ?Gbinding, may be predictors of bioavailability. The other thermodynamic quantities, ?Hbinding and ?Sbinding, are helpful in understanding the relative binding of the compounds. For example, acridine yellow G appears to be the least bioavailable of the three PANHs studied because of its strong ?Hbinding = ?29.8 kJ/mol, which leads to ?Gbinding = ?0.71 kJ/mol. While acridine orange and acridine have similar ?Hbinding values, acridine orange is more likely to bind to humic acid because the ?Sbinding for the process is less negative. Thermodynamic values and equilibrium binding constants for all three compounds are reported.
Effects of cervical arthrodesis and arthroplasty on neck response during a simulated frontal automobile collision.

BACKGROUND CONTEXT: While arthrodesis is the most common surgical intervention for treatment of symptomatic cervical degenerative disc disease (CDDD), arthroplasty has become increasingly more popular over the past decade. While literature exists comparing the effects of anterior cervical discectomy and fusion (ACDF) and cervical total disc replacement (CTDR) on neck kinematics and loading, the vast majority of these studies apply only quasi-static, non-injurious loading conditions to a segment of the cervical spine. PURPOSE: The objective of this study was to investigate the effects of arthrodesis and arthroplasty on biomechanical neck response during a simulated frontal automobile collision with airbag deployment. STUDY DESIGN: This study used a full-body, 50th percentile seated male finite element (FE) model to evaluate neck response during a dynamic impact event. The cervical spine was modified to simulate either an arthrodesis or arthroplasty procedure at C5-6. METHODS: Five simulations of a belted driver, subjected to a 13.3 m/s ΔV frontal impact with airbag deployment, were run in LS-DYNA with the Global Human Body Models Consortium (GHBMC) full-body FE model. The first simulation used the original model, with no modifications to the neck, while the remaining four were modified to represent either interbody arthrodesis or arthroplasty of C5-6. Cross-sectional forces and moments at the C5 and C6 cervical level of the neck, along with interbody and facet forces between C5 and C6, were reported. This study was funded by the United States Army Medical Research and Materiel Command. It was supported through a $1,514,365.00 grant and a $5,899.00 donation in product. The authors have no potential conflicts of interest to report. RESULTS: Adjacent-level, cross-sectional neck loading was maintained in all simulations without exceeding any established injury thresholds. Interbody compression was greatest for the CTDRs, and interbody tension occurred only in the fused and non-modified spines. Some interbody separation occurred between the superior and inferior components of the CTDRs during flexion-induced tension of the cervical spine, increasing the facet loads. CONCLUSIONS: This study evaluated the effects of C5-6 cervical arthrodesis and arthroplasty on neck response during a simulated frontal automobile impact. While cervical arthrodesis and arthroplasty at C5-6 did not appear to significantly alter the adjacent-level, cross-sectional neck responses during a simulated frontal automobile impact, key differences were noted in the interbody and facet loading. Language: en