cssi/SciSciGPT-SciSciNet huggingface dataset:
LPA-2 Receptor

The LPA2 receptor belongs to a group of G protein-coupled receptors called lysophospholipid receptors, which are activated by lysophosphatidic acid (LPA) and/or sphingosine 1-phosphate …
Entitlements in the crosshairs: how sovereign credit ratings judge the welfare state in advanced market economies

How do credit rating agencies (CRAs) judge welfare policies in advanced market economies (AMEs)? Scholars worry that market pressures constrain AMEs’ ability to retain their welfare arrangements, b...
A rare cause of atraumatic fractures: case series of four patients with tumor-induced osteomalacia.

Tumor-induced osteomalacia (TIO) is a rare paraneoplastic syndrome that presents with hypophosphatemia, bone pain, muscle weakness and fractures. We report a case series of four patients with TIO that resulted in significant muscle weakness and multiple atraumatic fractures. Four patients were referred to an endocrinology clinic for the evaluation of multiple atraumatic fractures, muscle weakness, generalized muscle and joint pain. Laboratory evaluation was notable for persistent hypophosphatemia due to urinary phosphate wasting, low to low-normal 1,25-dihydroxyvitamin D, elevated alkaline phosphatase and elevated fibroblast growth factor 23 (FGF23). Tumor localization was successful, and all four patients underwent resection of phosphaturic mesenchymal tumors. Post-operatively, patients exhibited normalization of serum phosphorus, in addition to significant improvement in their ambulatory function. Hypophosphatemia with elevated FGF23 and low 1,25-dihydroxyvitamin D level in the setting of multiple atraumatic fractures necessitates careful evaluation for biochemical evidence of tumor-induced osteomalacia.
A theoretical consideration of the ballistic response of continuous graphene membranes

Abstract The remarkable properties of graphene, including unusually high mechanical strength and stiffness, have been well-documented. In this paper, we combine an analytical solution for ballistic impact into a thin isotropic membrane, with ab initio density functional theory calculations for graphene under uniaxial tension, to predict the penetration resistance of multi-layer graphene membranes. The calculations show that continuous graphene membranes could enable ballistic barriers of extraordinary performance, enabling resistance to penetration at masses up to 100× lighter than existing state-of-the-art barrier materials. The very high elastic wave speed and strain energy to failure are the major drivers of this increase in performance. However, the in-plane mechanical isotropy of graphene, as compared to conventional orthotropic woven textiles, also contributes significantly to the efficiency of graphene as a barrier material. This result suggests that, for barrier applications, isotropic membranes composed of covalently bonded two-dimensional molecular networks could provide distinct advantages over fiber-based textiles derived from linear polymers.
Dynamics and nonmonotonic drag for individually driven skyrmions

We examine the motion of an individual skyrmion driven through an assembly of other skyrmions by a constant or increasing force in the absence of quenched disorder. The skyrmion behavior is determined by the ratio of the damping and Magnus terms, as expressed in terms of the intrinsic skyrmion Hall angle. For a fixed driving force in the damping dominated regime, the effective viscosity decreases monotonically with increasing skyrmion density, similar to what is observed in overdamped systems where it becomes difficult for the driven particle to traverse the surrounding medium at high densities. In contrast, in the Magnus dominated regime the velocity dependence on the density is nonmonotonic, and there is a regime in which the skyrmion moves faster with increasing density, as well as a pronounced speed-up effect in which a skyrmion traveling through a dense medium moves more rapidly than it would at low densities or in the single particle limit. At higher densities, the effective damping increases and the velocity decreases. The velocity-force curves in the Magnus-dominated regime show marked differences from those in the damping-dominated regimes. Under an increasing drive we find that there is a threshold force for skyrmion motion which increases with density. Additionally, the skyrmion Hall angle is drive dependent, starting near zero at the threshold for motion and increasing with increasing drive before reaching a saturation value, similar to the behavior found for skyrmions driven over quenched disorder. We map dynamic phase diagrams showing the threshold for motion, nonlinear flow, speed-up, and saturation regimes. We also find that in some cases, increasing the density can reduce the skyrmion Hall angle while producing a velocity boost, which could be valuable for applications.
Understanding the Si 7x 7: Energetics, Topology, and Stress

Several experiments [1-4] strongly support the “dimer adatom stacking-fault” (OAS) model of TAKAYANAGI et al.[1] as being the correct structural model for the Si 7×7. Attention is now shifting towards attempts to understand the reasons for the formation of this structure. McRAE [5] has suggested that relief of a strong compressive surface stress [6] is the driving force for the reconstruction. QIAN and CHAOI [7] and NORTHRUP [8] have emohasized danglinqbond reduction and adatom formation as the driving mechanisms. A successful theory should discriminate among these possibilities, identify the factors which determine the DAS periodicity, elucidate the relationship of the Si 7×7 to the Ge c2×8, and explain experiments showing a strain-dependence of the surface reconstruction pattern [9-13].
Histological preparation of Xenopus laevis oocytes and embryos.

Publisher Summary This chapter outlines the techniques that are used successfully in laboratory to examine morphologically oogenesis and particularly embryogenesis under normal and experimental conditions. Modified Karnovsky fixative containing dimethyl sulfoxide (DMSO) is ideal for preserving Xenopus tissue for transmission (TEM) and scanning electron microscopy (SEM); however it is not suitable for immunostaining. Fixatives specific for electron microscopy are generally not ideal for immunohistochemical analyses because (1) paraformaldehyde alone may maintain antigenicity however is not the most optimal fixative for preserving ultrastructural elements; and (2) glutaraldehyde, an excellent cross-linker, may severely reduce the antigenicity of many proteins. For immunostaining, the chapter describes a fixative thatmeets the important criteria of balancing the maintenance of antigenicity within the tissue with the best possible retention of the normal cellular morphology. The chapter outlines two such variations which not only illustrate differences but actually show results which complement each other.
QUALITY OF RAW CHICKEN BREAST STORED AT 5C AND PACKAGED UNDER DIFFERENT MODIFIED ATMOSPHERES

The objective of this study was to determine the quality of raw chicken breast store at 5C and packaged under different modified atmospheres. The samples of raw chicken breast (20 samples per treatment) were individually wrapped and packed in high-density plastic bags. Before sealing, the air was removed automatically by an air removal system (vacuum) and then injected into different mixtures of purified natural gas. Physicochemical analysis of texture, pH, thiobarbituric acid (TBA), total volatile bases (TVB), color and microbiological analyses (mesophilic aerobic, Staphylococcus, psychrotrophic, Salmonella and Escherichia coli) were carried out. The cutting strengths and TBA of the control sample after 9 days of storage were 0.94 kgf and 0.601, respectively, there was lower browning, variation in pH, TBA and nitrogen TVB, and a lower growth of psychrotrophic, mesophilic and Staphylococcus was shown; the absence of Salmonella and Escherichia coli is noted. It can be concluded that the best treatment is C after 9 days of storage obtaining a longer shelf life of the chicken breast meat. PRACTICAL APPLICATIONS The deterioration of foods caused by internal and external factors are responsible for considerable economic loss. Chicken breast meat is easily perishable by microorganisms depending on conditions of supply and production chain. An alternative to try to minimize the losses and increase the shelf life of this product is the use of modified atmospheres. The use of modified atmospheres in this study was effective to retard spoilage and reduce the volatile compounds in chicken breast meat, thus increasing food security without bringing risk to public health.
Differential gene expression in Arabidopsis wild‐type and mutant anthers: insights into anther cell differentiation and regulatory networks

Summary In flowering plants, the anther contains highly specialized reproductive and somatic cells that are required for male fertility. Genetic studies have uncovered several genes that are important for anther development. However, little information is available regarding most genes active during anther development, including possible relationships between these genes and genetically defined regulators. In Arabidopsis, two previously isolated male-sterile mutants display dramatically altered anther cell differentiation patterns. The sporocyteless (spl)/nozzle (nzz) mutant is defective in the differentiation of primary sporogenous cells into microsporocytes, and does not properly form the anther wall. The excess microsporocytes1 (ems1)/extrasporogenous cells (exs) mutants produce excess microsporocytes at the expense of the tapetum. To gain additional insights into microsporocyte and tapetum differentiation and to uncover potential genetic interactions, expression profiles were compared between wild-type anthers (stage 4–6) and those of the spl or ems1 mutants. A total of 1954 genes were found to be differentially expressed in the ems1 and/or spl anthers, and these were grouped into 14 co-expression clusters. The presence of genes with known and predicted functions in specific clusters suggests potential functions for other genes in the same cluster. To obtain clues about possible co-regulation within co-expression clusters, we searched for shared cis-regulatory motifs in putative promoter regions. Our analyses were combined with data from previous studies to develop a model of the anther gene regulatory network. This model includes hypotheses that can be tested experimentally to gain further understanding of the mechanisms controlling anther development.
Resolution of linear/nonlinear inconsistencies in charge-conservative FET models

The presence of a nonlinear capacitor in a circuit model mathematically implies the existence of a parallel transcapacitor, if the value of its capacitance is a function of a remote voltage. As a consequence, simulating small-signal excursions with a nonlinear model produces data which is inconsistent with the simulations using the small-signal model, if the latter does not include the transcapacitance. However including the transcapacitance in the small-signal model is complicated by several effects. Furthermore, the transcapacitance seems to confound the convergence of the harmonic balance simulation algorithm. Herein, a new mathematical formulation has been concocted which renders the transcapacitance equal to zero at any prescribed quiescent point, and thus negligible for moderate large-signal excursions therefrom. As a result, the small and large signal models are consistent and harmonic balance convergence capabilities is improved.
Detecting the Noteworthiness of Utterances in Human Meetings

Our goal is to make note-taking easier in meetings by automatically detecting noteworthy utterances in verbal exchanges and suggesting them to meeting participants for inclusion in their notes. To show feasibility of such a process we conducted a Wizard of Oz study where the Wizard picked automatically transcribed utterances that he judged as noteworthy, and suggested their contents to the participants as notes. Over 9 meetings, participants accepted 35% of these suggestions. Further, 41.5% of their notes at the end of the meeting contained Wizard-suggested text. Next, in order to perform noteworthiness detection automatically, we annotated a set of 6 meetings with a 3-level noteworthiness annotation scheme, which is a break from the binary "in summary"/"not in summary" labeling typically used in speech summarization. We report Kappa of 0.44 for the 3-way classification, and 0.58 when two of the 3 labels are merged into one. Finally, we trained an SVM classifier on this annotated data; this classifier's performance lies between that of trivial baselines and inter-annotator agreement.
Nanoclay-induced morphology development in chaotic mixing of immiscible polymers

This study investigated the role of layered silicate clay on morphology development in chaotic mixing of two immiscible polymers, polypropylene (PP) and polyamide 6 (PA6). The study showed that clay particles helped to produce droplets of much smaller size and with narrower size distribution due to their direct influence on the breakup of PP domains. In the experiments, a small quantity of organically modified layered silicate clay was initially mixed in PP and the mixture was blended with PA6 in a chaotic mixer. All morphological forms, such as lamellas, fibrils, and droplets were seen as in the case with no clay. The clay particles reduced interfacial tension between PP and PA6 phases. As a consequence, the PP domains sustained lamellar and fibrillar forms, and thin fibrils were formed. These thin fibrils in turn broke rapidly into smaller droplets. It was also found that a large fraction of clay particles migrated into PA6 phase and contained intercalated PA6 chains in their galleries. These results indicate that clay particles did not participate in compatibilization in this system. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 3638–3651, 2005
Electromyographic Feedback and Taped Relaxation Instructions to Modify Hypnotic Susceptibility and Amnesia

Abstract The comparative effectiveness of electromyographic (EMG) feedback and taped verbal relaxation instructions in increasing both hypnotic susceptibility and hypnotic amnesia was assessed. Twenty-four moderately susceptible, nonamnesic subjects were pretested on the Stanford Hypnotic Susceptibility Scale — Form A and then randomly assigned to one of three conditions: EMG feedback, verbal relaxation training, or no contact control. All subjects were posttested with the Stanford Hypnotic Susceptibility Scale — Form B, ten days after initial contact. The hypnotic susceptibility scores of the subjects who received EMG feedback increased significantly. Amnesia scores for these subjects did not change significantly. The relaxation and control groups did not change significantly on either measure. Implications of the results were discussed with respect to previous work in the area.
Topographic nomenclature on planetary bodies

Abstract General guidlines are presented for International Astronomical Union decisions on nomenclature for surface features on the planets and their satellites.
Formin Tip Tracking

Eukaryotic cells, including those of humans, depend on filaments of actin protein for their physical integrity and movements. Formins are a class of proteins that regulate actin assembly, producing filaments that participate in cell division, cell migration, and intracellular transport, among other cellular processes ( 1 ). Although many proteins have been identified that regulate actin, we need to better understand their modes of action at the molecular level. Technical advances, such as single-molecule imaging in real time with purified proteins and in live cells, are extending this knowledge. On page 80 of this issue, Mizuno et al. ( 2 ) present a method for visualizing the rotational movement of actin filaments as they grow from immobilized formin proteins. The study confirms that actin elongation is coupled to rotation motion of the filament, and provides clues about how formins might transmit actin-generated force to other cellular structures.
Absorption effects in photopolymerized ceramic suspensions

Abstract The effects of concentration of photoinitiator and concentration of an ultraviolet-absorbing dye on the cure depth and cure width of photopolymerized ceramic suspensions were investigated. Both the cure depth and cure width have a semilogarithmic dependence on the energy dose, with the suspension characterized by the following parameters: the depth critical energy dose and depth sensitivity and width critical energy dose and width sensitivity. The values of these four parameters are highly dependent on the concentration of absorbers in the suspension. The depth sensitivities and width sensitivities are given by the absorption model, while the depth critical energy doses and width critical energy doses are given by the inhibitor exhaustion model. Furthermore, the relationship between concentration of absorbers and the broadening depth was determined. The concentration of photoinitiator did not significantly change the broadening depth, while the concentration of dye decreased the broadening depth.
Electrophoretic light scattering studies of poly(L‐lysine) in the ordinary and extraordinary phase. Effects of salt, molecular weight, and polyion concentration

Electrophoretic light scattering (ELS) is employed to determine the electrophoretic mobilities μE and apparent diffusion coefficients DELS obtained from ELS linewidths for three samples of poly(L‐lysine)HBr (PLL) of degree of polymerization n=406, n=946, and n=2273 as a function of salt (Cs) and polyion (Cp) concentration. Dynamic light scattering (DLS) is used to determine apparent diffusion coefficients Dapp of these same PLL samples in the absence of the applied field. The polyelectrolyte system exhibits an ordinary to extraordinary phase transition at low salt concentrations that is manifested by a more than 50‐fold decrease in Dapp as well as a twofold decrease in scattered intensity. In the extraordinary phase, the DELS values are typically very small, though still somewhat (frequently twofold) larger than Dapp. When the salt concentration is raised to enter the ordinary phase DELS remains small, less than one tenth of Dapp, in the low‐salt end of the ordinary phase, but increases with increasing Cs...
Encoding First Order Proofs in SMT

We present a method for encoding first order proofs in SMT. Our implementation, called ChewTPTP-SMT, transforms a set of first order clauses into a propositional encoding (modulo theories) of the existence of a rigid first order connection tableau and the satisfiability of unification constraints, which is then fed to Yices. For the unification constraints, terms are represented as recursive datatypes, and unification constraints are equations on terms. The finiteness of the tableau is encoded by linear real arithmetic inequalities. We compare our implementation with our previous implementation ChewTPTP-SAT, encoding rigid connection tableau in SAT, and show that for Horn clauses many fewer propositional clauses are generated by ChewTPTP-SMT, and ChewTPTP-SMT is much faster than ChewTPTP-SAT. This is not the case for our non-Horn clause encoding. We explain this, and we conjecture a rule of thumb on when to use theories in encoding a problem.
Reduced damping of surface plasmons at low temperatures

We investigated the effectiveness of low temperatures in reducing plasmon damping by measuring the homogeneous linewidth of plasmon resonances $(\ensuremath{\sim}1.5\text{ }\text{eV})$ in nanoscale gold bipyramids at temperatures from 293 to 6 K. The linewidth drops linearly with temperature and approaches a constant value at approximately 50 K. Measurements were performed on monodisperse ensembles as well as on single particles. The 30% decrease in the homogeneous linewidth with decreasing temperature is well accounted for by the reduced electron-phonon scattering. The other relaxation mechanisms---electron-electron scattering, electron-surface scattering, and radiative relaxation---do not change significantly with temperature.
Reducing Mortality Related to Adverse Events in Children

Since the launch of the 100,000 Lives Campaign by the Institute for Healthcare Improvement (IHI), preventing medical adverse events to reduce avoidable mortality has emerged as a central focus for health care providers, institutions, regulators, insurance companies, and patients. Evidence-based interventions targeting the 6 interventions in the campaign have been associated with a reduction in preventable hospital deaths in the United States. The generalizability of the IHI's campaign to the pediatric population is only partly applicable. Pediatric experiences with rapid response teams and preventing central-line infections parallel the published experience of adults, with promise to significantly reduce preventable pediatric mortality.
Fatigue crack growth in unidirectional graphite-epoxy composites under cyclic compression

It is shown that in addition to the well-known failure process involving kink band formation, the application of cyclic compressive loads to notched plates of graphitr-epoxy composites can lead to the nucleation and growth of a single fatigue crack normal to the compression axis and to the fibre direction. This stable mode I compression fatigue fracture is a consequence of the generation of a zone of residual tensile stresses within the notch-tip region where deformation occurs in the form of matrix cracking, fibre breakage, fibre buckling nad/or interfacial debonding
The Epidemiology of Venous Thromboembolism

Venous thromboembolism (VTE) is categorized by the U.S. Surgeon General as a major public health problem. VTE is relatively common and associated with reduced survival and substantial health-care costs, and recurs frequently. VTE is a complex (multifactorial) disease, involving interactions between acquired or inherited predispositions to thrombosis and VTE risk factors, including increasing patient age and obesity, hospitalization for surgery or acute illness, nursing-home confinement, active cancer, trauma or fracture, immobility or leg paresis, superficial vein thrombosis, and, in women, pregnancy and puerperium, oral contraception, and hormone therapy. Although independent VTE risk factors and predictors of VTE recurrence have been identified, and effective primary and secondary prophylaxis is available, the occurrence of VTE seems to be relatively constant, or even increasing.
N-Band Polymorphism of Human Acrocentric Chromosomes and Its Relevance to Satellite Association

With the aid of Q- and N-banding techniques we investigated the relationship between the length of satellite stalks, the appearance of N-bands and the frequency of satellite association of individual acrocentric chromosomes in the cells of seven individuals, including one male with a satellited and small Y-chromosome. The appearance of N-bands seemed to be a constant and characteristic property of individual acrocentric chromosomes, independent of the status of concentration of the chromosomes at metaphase. The homolog with longer satellite stalks had larger N-bands and participated in satellite association at a higher frequency than the one with shorter stalks. It appeared that N-bands were present along the whole length of the satellite stalk, the size of which could possibly reflect the amount of rDNA present in the nucleolar organizers in human chromosomes.
Microdielectric monitoring of prepreg cure

The feasibility of using a microdielectric sensor to characterize the cure behavior of a commercial prepreg roving was investigated. Chemical and physical characterization methods were first used to determine the uniformity of the prepreg material. Thermal, dynamic mechanical, and dielectric methods were then utilized to monitor the cure cycle. The dielectric response was found to be independent of the glass fibers of the prepreg and to show reproducible changes in the early part of cure over a temperature range of 80 to 135°C. The manufacturer's recommended cure temperature of 121°C (250°F) was found to correspond to the onset of the ultimate glass transition of the material. Variations in the dielectric response in the latter part of cure at this temperature and above were attributed in part to this event.
Construction of a physical model of the human carotid artery based upon in vivo magnetic resonance images.

To verify the validity of model transformation represented byEq. ~16!, we compared its numerical solution to that of the origi-nal problem statement, Eqs. ~1! and ~2!. The numerical solution ofEqs. ~1! and ~2! was obtained using the method of lines imple-mented by DSS/2 as described by Schiesser and Silebi @2#. Thisprogram discretizes the spatial derivatives while incorporating theboundary conditions to produce a set of differential-differenceequations. The resulting initial-value problem was solved numeri-cally using a stiff-sparse integrator, LSODES@3#, which is avail-able from odepack/lsodes.f at http://www.netlib.org/liblist.html.To solve Eq. ~16!, we applied the Gauss–Kronrod program for theconvolution integral and RKF45 as the ODE intergrator. Thecodes for DSS/2 and RKF45 can be downloaded from http://www.lehigh.edu/;wes1/ctp/library/library.html. We veriﬁed thatthe numerical solutions of these two model representations areidentical within an arbitrarily small error. Using LSODES, wenumerically evaluated the approximate model transformation rep-resented by Eq. ~17!. The approximate transformation as a singleODE can be solved much faster than the exact transformation as asingle differential-convolution integral equation.
THE PATTERN RECOGNITION PROBLEMIMAN, MACHINE AND THEIR INTERACTION

Perception of texture has long been recognized as important for pattern identification. This paper examines the interaction between machine solutions and human judgement regarding dissimilarity among map pairs by testing twenty human subjects and using four choropleth maps of population density. Judged relations among the four systematically-contrived density maps produced a 'tone-texture' model in which individual differences existed almost exclusively in terms of how these two dimensions were weighted. Since significant individual differences exist in visual pattern discrimination an efficient man-machine interactive data processing system requires careful human engineering design so that the differentiated individual abilities can be taken into consideration. On a depuis longtemps reconnu l'importance de la perception des textures dans l'identification des motifs. A l'aide de vingt sujets humains de quatre cartes choroplethes de densite demographique, l'auteur etudie l'interaction des solutions mecaniq...
A requirement for an unconjugated pteridine for the growth of Paramecium aurelia

Abstract The ciliated protozoan Paramecium aurelia requires exceptionally high levels (microgram amounts) of folic acid for optimal growth when cultured in a compex synthetic medium. This requirement may be replaced by nanogram quantities of the vitamin provided the unconjugated pteridine biopterin is present in the medium. Both folic acid and biopterin are essential for optimal growth. Evidence has been obtained that the growth-promoting effect of abnormally high concentrations of folic acid may be due to the ability of the protozoan to convert small quantities of the vitamin into biopterin or other nutritionally active pteridines.
Efficient temporal compression in wireless sensor networks

Energy efficiency is critical in the design and deployment of wireless sensor networks. Data compression is a significant approach to reducing energy consumption of data gathering in multi-hop sensor networks. Existing compression algorithms, however, only apply to either lossless or lossy compression, but not to both. This paper presents a unified algorithmic framework to both lossless and lossy data compression, thus effectively supporting the desirable flexibility of choosing either lossless or lossy compression in an on-demand fashion based on given applications. We analytically prove that the performance of the proposed framework for lossless compression is superior to or at least equivalent to that of traditional predictive coding schemes regardless of any entropy encoders used. We demonstrate the merits of our proposed framework in comparison with other recently proposed compression algorithms for wireless sensor networks including LEC, S-LZW and LTC using various real-world sensor data sets.
Preparation of thin gold films by the forward-sputtering method

Abstract Au films are deposited on air-cleaved MgO(100) substrate by forward sputtering under various conditions of ion energy and ion species and the differences in their structural features are examined. The films have a mixture of (111) and (100) orientations. When the ion energy decreases or when the ion mass increases, the growth of (100)-oriented deposits is enhanced. Mostly (100)-oriented Au films are obtained below 500 °C. The defect density in Au films deposited by Au 3+ ions seems to be lower than that in Au films deposited by other ions. The surface morphology is also changed by the ion species. With lighter ions (C + , O + ) a relatively uniform surface is observed, while with heavier ions (Si + , Au 3+ ) a grain structure becomes clear. From these results it is believed that the structural features of Au deposits can be favourably changed by forward-sputtering deposition.
The Morality of May 2, 2011: A Content Analysis of U.S. Headlines Regarding the Death of Osama bin Laden

Following the death of Osama bin Laden in the late hours of May 1, 2011, many print newspapers throughout the United States and the world ran front-page coverage of his death the following day. Although public support for bin Laden's death was largely consistent, newspaper headlines across the country varied in their presentation of the story, from “Got the Bastard!” to a more stoic “bin Laden dead.” Content analysis derived from the model of intuitive morality and exemplars (MIME) was applied to explain variance in headlines as a function of the dominant political philosophy found in different areas of the United States—philosophies rooted in moral salience structures. The MIME suggests a reciprocal relationship between basic motivations underlying moral judgment for distinct audiences and media content produced for those audiences. Consistent with predictions, findings suggest that newspapers in conservative-leaning regions presented the story as a patriotic “killing” (an emphasis on authority and loyal...
REGENERATION OF PERIPHERAL-NERVE DEFECTS BY IRRADIATED HOMOGRAFTS

A new method, employing ionizing radiation, is described for preparing peripheral nerves for homografting procedures. Nerve grafts were removed and immediately placed in polyethylene tubing, stored at -12 deg F, and later irradiated with 2,000,000 rep high-energy electrons for 10 sec at the temperature of dry ice with a Van de Graaff generator. Wistar and Long-Evans rats were used as donors and recipients to test the irradiated nerves. In each recipient rat an irradiated nerve and a nerve treated in a similar manner but without irradiation were implanted subcutaneously into separate legs. The nonirradiated grafts provoked a strong inflammatory response, and those which had been irradiated provoked little or no such response. Also, 3- to 4-cm defects were created in the proximal portion of the peroneal nerves of mongrel dogs, and irradiated nerve grafts prepared in the same manner were sutured into place. Within six months, return of function was seen in all the dogs. Because the results in these animal experiments were so uniformly successful, clinical use of the same technique was planned. Irradiated human nerve grafts were prepared from the tibial nerve of an amputated leg, and the successful results in the first two patients are reported. Amore » 3-in. homograft was inserted in the median nerve at the wrist of a patient who had lost a segment of nerve a year previously. Four months after the grafting of irradiated nerve the patient had return of sensation in the thumb and 4 fingers. Clinical repair was also attempted in a 19-yrold boy who had lost 5 in. of his ulnar nerve from a gunshot injury, with complete loss of function. A 51/2-in. irradiated tibial graft was inserted into this large defect and 5 months later he had a return of sensation in ihe palm and fourth finger. (BBB)« less
Electrostatics of DNA–DNA juxtapositions: consequences for type II topoisomerase function

Type II topoisomerases resolve problematic DNA topologies such as knots, catenanes, and supercoils that arise as a consequence of DNA replication and recombination. Failure to remove problematic DNA topologies prohibits cell division and can result in cell death or genetic mutation. Such catastrophic consequences make topoisomerases an effective target for antibiotics and anticancer agents. Despite their biological and clinical importance, little is understood about how a topoisomerase differentiates DNA topologies in a molecule that is significantly larger than the topoisomerase itself. It has been proposed that type II topoisomerases recognize angle and curvature between two DNA helices characteristic of knotted and catenated DNA to account for the enzyme's preference to unlink instead of link DNA. Here we consider the electrostatic potential of DNA juxtapositions to determine the possibility of juxtapositions occurring through Brownian diffusion. We found that despite the large negative electrostatic potential formed between two juxtaposed DNA helices, a bulk counterion concentration as small as 50 mM provides sufficient electrostatic screening to prohibit significant interaction beyond an interhelical separation of 3 nm in both hooked and free juxtapositions. This suggests that instead of electrostatics, mechanical forces such as those occurring in anaphase, knots, catenanes, or the writhe of supercoiled DNA may be responsible for the formation of DNA juxtapositions.
Higher multipole and retardation corrections to the dipole angular distributions of L-shell photoelectrons ejected by polarized photons.

We calculate first-retardation and multipole corrections to the dipole angular distributions of L-shell photoelectrons ejected by polarized photons. The calculation is performed nonrelativistically in the framework of the independent-particle model. It leads to general expressions for the s and p subshell retardation correction in terms of radial matrix elements and relative phase shifts. In the 2s case the retardation effects may contribute as much as 10--30% to the angular distribution even close to threshold, especially for higher-Z elements. In the 2p case the retardation effects are small close to threshold but can contribute as much as 10--20% for relatively low final electron energies of 1--3 keV. We have also obtained simple semianalytical expressions for the retardation corrections, based on the assumption that for inner shells screening effects beyond normalizations and phase shifts can be treated perturbatively. The semianalytic formulas compare quite well with the results of numerical calculations for the 2s subshell; they are somewhat worse for 2p photoelectrons, especially for lower energies and lower Z. This is due to the fact that in the latter case larger distances become more important in the integrals determining radial matrix elements. In the 2s case the retardation effects result in forward or backward peaking of the angular distributions. For the 2p initial state and linearly polarized photons, they lead to deviations from dipole predictions for a uniform angular distribution of photoelectrons whose momenta are perpendicular to the direction of photon polarization.
Ethnic peace, ethnic conflict: Complexity theory on why the Baltic is not the Balkans

Abstract As Communist rule weakened across East Central Europe and new governments emerged, the Baltic region differed from the Balkans in two ways that need to be explained. The first difference was the near absence of ethnic violence in Estonia, Latvia, and Lithuania – compared to civil and cross-border war in most of the former Yugoslavia. The second contrast was the rapid consolidation of democracy and market economics in the Baltic countries compared to halting movements toward political and economic freedom in most Balkan polities.
Worldliness or Unwordliness? The Issue between Bonhoeffer and Bultmann as seen by Ronald Gregor Smith

The names of Dietrich Bonhoeffer and Rudolf Bultmann have frequently and inevitably been associated in theological debate since the Second World War. On a popular level in the English-speaking world, it was perhaps J. A. T. Robinson's Honest to God (1963) which most notably placed Bonhoeffer alongside Bultmann, along with Tillich, as close allies in the search for a fresh and viable understanding of God.
"Better the devil you know": a preliminary study of the differential modulating effects of reputation on reward processing for boys with and without externalizing behavior problems.

Very little is known about the neurobiological correlates of reward processing during social decision-making in the developing brain and whether prior social and moral information (reputations) modulates reward responses in youth as has been demonstrated in adults. Moreover, although externalizing behavior problems in youth are associated with deficits in reward processing and social cognition, a real-life social interaction paradigm using functional neuroimaging (fMRI) has not yet been applied to probe reward processing in such youth. Functional neuroimaging was used to examine the neural correlates of reward-related decision-making during a trust task in two samples of age-matched 11 to 16-year-old boys: with (n = 10) and without (n = 10) externalizing behavior problems. The task required subjects to decide whether to share or keep monetary rewards from partners they themselves identified during a real-life peer sociometric procedure as interpersonally aggressive or kind (vs. neutral). Results supported the notion that prior social and moral information (reputations) modulated reward responses in the adolescent brain. Moreover, boys with externalizing problems showed differential activation in the bilateral insula during the decision phase of the game as well as the caudate and anterior insula during the outcome phase of the game. Similar activation in adolescents in response to reward related stimuli as found in adults suggests some developmental continuity in corticostriatal circuits. Group differences are interpreted with caution given the small group sizes in the current study. Notwithstanding this limitation, the study provides preliminary evidence for anomalous reward responses in boys with externalizing behavior problems, thereby providing a possible biological correlate of well-established social-cognitive and reward-related theories of externalizing behavior disorders.
The Use of Tetrahymena to Evaluate the Effects of Gamma Radiation on Essential Nutrilites

The complete synthetic medium for the growth of Tetrahymena pyriformis E was subjected to gamma-radiation from cobalt60. A dose-response curve indicated the range of radiation which damaged the medium so that growth of Tetrahymena was inhibited. The essential vitamins and amino acids which comprise the medium were individually irradiated in solution. Media were prepared with single irradiated components and tested for their ability to support growth of the protozoa. Thiamine, riboflavin, pantothenate, pyridoxine, folic acid, and thioctic acid were destroyed by less than 1 × 106 rep, while 2 × 106 rep was required to inactivate nicotinic acid. Most amino acids proved to be relatively radiation-resistant. At the high radiation levels of 1 × 107 rep and 2.3 × 107 rep respectively, only serine and methionine were damaged. All other amino acids remained biologically active even after receiving 2.3 × 107 rep, the highest level of radiation employed. Organoleptic observations, however, showed radiation-caused color and odor changes in many of those amino acids whose biological activity for Tetrahymena was unaffected. The nucleotide, guanylic acid, was also inactivated at 2.3 × 107 rep.
Comparison of the CEDIA and MEIA assays for measurement of tacrolimus in organ transplant recipients.

Abstract Objectives Tacrolimus is widely used in organ transplantation. We evaluated 2 immunoassays, CEDIA® and MEIA®, for the measurement of whole blood tacrolimus concentrations. Methods For each assay the following were evaluated: total precision, limit of detection (analytical sensitivity), limit of quantitation (functional sensitivity), linearity, and accuracy. Patient correlation studies were performed, comparing each assay with liquid chromatography-tandem mass spectrometry (LC-MS/MS). Results Total precision for MEIA, corresponding to mean concentrations of 6.8 and 22.5 ng/ml, was 17.4 and 11.9%, respectively. The limit of detection was 0.9 ng/ml, and the limit of quantitation was 4.7 ng/ml. Total precision for CEDIA, corresponding to mean concentrations of 5.3 and 19.9 ng/ml, was 20.6 and 6.3%, respectively. The limit of detection was 0.8 ng/ml, with a limit of quantitation of 4.9 ng/ml. Analysis of proficiency material demonstrated acceptable performance for both assays. In addition, both assays were acceptably linear over their respective reportable ranges. Analysis of patient correlation data using Passing–Bablok analysis and Bland–Altman plots demonstrated a positive average bias for both assays versus LC-MS/MS results. Conclusion Based on our evaluation, both assays demonstrated acceptable performance for use in clinical monitoring of tacrolimus.
A probabilistic heuristic for a computationally difficult set covering problem

An efficient probabilistic set covering heuristic is presented. The heuristic is evaluated on empirically difficult to solve set covering problems that arise from Steiner triple systems. The optimal solution to only a few of these instances is known. The heuristic provides these solutions as well as the best known solutions to all other instances attempted.
On the fly nodal searches in importance sampled fixed-node diffusion Monte Carlo using a parallel, fine-grained, genetic algorithm

Abstract A method for finding nodal surfaces on the fly in importance-sampled, fixed-node diffusion Monte Carlo calculations is described. The procedure relies on minimizing the difference between the nodal functions of the guiding wave function, Ψ T , and H ˆ Ψ T , where H ˆ is the Hamiltonian. This is done by allowing the trial function to depend on a set of parameters whose values are then optimized using a parallel genetic algorithm (e.g., the Pikaia code developed in astrophysics). Application is made to the calculation of several excited states of a non-integrable two-dimensional quartic oscillator and to excited states of the He–C 2 H 2 complex.
Description of the ground state electronic structures of Cu2O, Cu2S, Ag2O and Ag2S

Abstract The electronic structures of the copper and silver oxides Cu 2 O, Cu 2 S, Ag 2 O and Ag 2 S have been calculated in the local density functional approximation. The structures closely resemble an O − or S − bridging an M + 2 as shown by the geometries and the charge distributions. The symmetric stretch frequency exceeds that of the asymmetric stretch as well as the stretch in the free diatomic. The electronic structures of the oxides and sulfides are similar with the HOMO having most of its density on the oxygen or sulfur. The predicted ionization potentials are also similar.
Scopolamine effects on memory retention in mice: A model of dementia?

Scopolamine-treated normal young human subjects exhibit memory dysfunctions analogous to those observed in demented patients. The dysfunctions are reversible by physostigmine but not by d-amphetamine which suggests that the memory impairment is specifically related to reduced cholinergic transmission caused by scopolamine. Scopolamine-induced amnesia has been proposed as a model for dementia where reduced cholinergic function is the suspected cause. We report seven experiments in young adult mice which examine scopolamine's effects on memory retention and whether its amnestic effects are specifically blocked by cholinergic agonists or cholinomimetics. Young adult mice were trained to avoid footshock in a T maze and their retention tested 1 week after training. Pretraining subcutaneous injection of scopolamine improved retention scores of “undertrained” mice at a dose of 0.01 mg/kg but impaired at a dose of 0.1 mg/kg. Post-training injection showed no effect at 0.01 mg/kg, enhanced retention scores at 0.1 mg/kg, and impaired at 1.0 mg/kg. The impairment by 1.0 mg/kg was blocked by injection 45 min post-training of each of two cholinergic drugs but was also counteracted by six drugs which act upon five other neural systems (catecholamine, serotonin, glycine, GABA, and hormonal). When scopolamine was injected 40 min pretraining, and each of eight drugs was injected immediately after training, the amnestic effect of scopolamine was only partially counteracted. This suggests that scopolamine impaired acquisition, in addition to some impairment of memory processing. This was confirmed by a direct study of acquisition rates of the avoidance response; 0.1 mg/kg of scopolamine impaired acquisition. The overall results indicate that pretraining administration of scopolamine impairs learning and to some degree memory processing. Counteracting scopolamine-induced amnesia, by either pretraining or post-training drug administration, is not specific to the cholinergic system.
Divide and Conquer: A Theory of Intraday and Day-of-the-Week Mean Effects

This article develops a model in which pattern in buy and sell volume, order imbalances, and expected price changes arise endogenously. The model covers cases in which the market maker is competitive and is a monopolist. Our results provide an explanation for the existence of patterns in mean returns within the trading day and across trading days.
Age-related prognosis after acute myocardial infarction (The multicenter diltiazem postinfarction trial)

Abstract The basis for the excess mortality with age after acute myocardial infarction (AMI) is not clear, nor is it known whether the mode of death is altered with age. Age-related factors predictive of mortality and age-related mechanisms of the 333 deaths were examined in 2,466 patients who were enrolled in a placebo-controlled trial to determine the effect of diltiazem on mortality and reinfarction after AMI. There were 3 age groups with increasing mortality rates: ages 25 to 49 (n = 499), 50 to 64 (n = 1,228) and 65 to 75 years (n = 739). There was a significant age-related increase in the proportion of patients with baseline risk factors. These baseline characteristics did not differ by treatment (placebo vs diltiazem). However, multi-variate survivorship analysis still identified age as an independent risk factor for cardiac death. The proportion of arrhythmic and myocardial failure deaths did not differ by treatment or age group.
Design of Optimal Second-Order State Estimators

The present consideration of the design of online computation-saving second-order state estimators for second-order vector-matrix differential systems proposes a class of such estimators which is proven to possess guaranteed convergence. A class of optimal second-order estimators is then obtained, and the conditions required for optimality are identified. The estimator proposed offers high performance in conjunction with online computation reductions sufficiently great to allow the estimation of the large number of state variables associated with control of large, flexible space structures represented by high-dimensional second-order systems.