cssi/SciSciGPT-SciSciNet huggingface dataset:
Contact Transformations and Determinable Parameters in Spectroscopic Fitting Hamiltonians

Abstract In recent least-squares fits of torsion–rotation spectra of acetaldehyde and methanol it was found possible to adjust more fourth-order parameters than would be expected from traditional contact-transformation considerations. To investigate this discrepancy between theory and practice we have carried out numerical fitting experiments on the simpler three-dimensional (three-Eulerian-angle) asymmetric rotor problem, using J ≤ 20 unitless energy levels generated artificially from a full orthorhombic Hamiltonian with quadratic through octic operators in the angular momentum components. Results are analyzed using the condition number κ of the least-squares matrix, which is a measure of its invertibility in the presence of round-off and other errors. When κ is very large, parameters must be removed from the fit until κ becomes acceptably small, corresponding to procedures which lead to reduced Hamiltonians in molecular spectroscopy. We find that under certain circumstances κ can be decreased to an acceptable level for Hamiltonians which are only partially reduced when compared to Watson A and S reductions. Some insight into this behavior is obtained from classical mechanics and from the concept of delayed contact transformations. Transferring this numerical and algebraic understanding to the more complicated four-dimensional methyl-top internal rotor problem supports the empirical observation that presently existing data sets for methanol and acetaldehyde are most efficiently fit using partially reduced Hamiltonians and further suggests that expanding the methanol data set to transitions involving levels of higher J , K , and v t would favor even more strongly the use of partially reduced fourth-order Hamiltonians.
Virus induction of human IFNβ gene expression requires the assembly of an enhanceosome

We present evidence that transcriptional activation of the human interferon-beta (IFN beta) gene requires the assembly of a higher order transcription enhancer complex (enhanceosome). This multicomponent complex includes at least three distinct transcription factors and the high mobility group protein HMG I(Y). Both the in vitro assembly and in vivo transcriptional activity of this complex require a precise helical relationship between individual transcription factor-binding sites. In addition, HMG I(Y), which binds specifically to three sites within the enhancer, promotes cooperative binding of transcriptional factors in vitro and is required for transcriptional synergy between these factors in vivo. Thus, HMG I(Y) plays an essential role in the assembly and function of the IFN beta gene enhanceosome.
How might cannabinoids influence sexual behavior

Marijuana and hashish are widespread drugs of abuse that contain Δ9-tetrahydrocannabinol (THC), a bioactive ingredient best known for its psychotropic effects. Remarkably, THC also produces multiple nonpsychotropic effects: for example, analgesia, hypotension, modulation of bronchospasm, and reduction of inflammation (1–6). That THC also influences sexual behavior was clearly demonstrated for the first time in the early 1980s; yet the precise molecular mechanism of this effect has remained unsolved. In this issue of PNAS, Mani et al. (7) revisit these seminal experiments. They identify the molecular target by which THC affects sexual behavior, and unveil a remarkable operative cross talk mechanism between THC and the progesterone and dopamine signaling pathways, which were already known to play a central role in reproductive behavior.
Effects of acidic and basic fibroblast growth factors (aFGF, bFGF) on glial precursor cell proliferation: Age dependency and brain region specificity☆

Acidic fibroblast growth factor (aFGF) and basic fibroblast growth factor (bFGF) are present in high levels in most areas of the embryonic rodent brain. To begin to understand the role of these growth factors in brain development, the effects of aFGF and bFGF on dissociated cell cultures prepared from embryonic and neonatal rat brain were studied. Addition of aFGF and heparin or bFGF alone to serum-free cultures of the dissociated Embryonic Day (E) 14.5 mesencephalon stimulates cell proliferation, as judged by [3H]thymidine autoradiography, leading to a maximal 75-fold increase in the total number of cells. This effect is dose-dependent with half-maximal increases at concentrations of about 5-6 ng/ml of aFGF or bFGF and is inhibited by the FGF antagonist HBGF-1U. The effect of aFGF on cell proliferation in cultures prepared from E14.5 mesencephalon is similar to that in cultures prepared from E14.5 cortex. However, in cultures prepared from E14.5 rhombencephalon or diencephalon, the proliferative effect of aFGF is much reduced. In all brain areas studied, the proliferative effect of aFGF declines with increasing age. Immunocytochemical analysis of E14.5 mesencephalic cultures demonstrated that the aFGF-induced increase in cell number is due to the proliferation of A2B5-immunoreactive (IR) glial precursor cells, but not of neuronal precursors, fibroblasts, or microglial cells. Moreover, differentiated glial fibrillary acidic protein-IR astrocytes and 2',3'-cyclic nucleotide 3'-phosphohydrolase-IR oligodendrocytes were not observed in cultures continuously treated with aFGF or bFGF, but were observed in high numbers after removal of the growth factors. These results suggest (1) that aFGF and bFGF are potent mitogens for glial precursor cells in all embryonic brain regions, (2) that the magnitude of the effects of aFGF depends on embryonic age and brain region, and (3) that both growth factors inhibit the differentiation of astrocyte or oligodendrocyte precursors. These observations made in vitro strongly support the hypothesis that FGF plays a critical role in gliogenesis and the timing of glial differentiation in the brain.
Theory Construction in SLA

There are indications that a determined effort toward theory construction is currently being mounted in SLA (Gregg, 1989, 1990; Long, 1990; Spolsky, 1989). This raises a number of epistemological issues, one of which is the question of multiple theories and lack of convergence (and the related question of distinguishing science from nonscience–and from nonsense). In a field where there are many different therorise, is the relationship between them one of complementarity or of opposition? Are there criteria for appraisal and choice? Issues relating to theory construction have received considerable attention in the literature (e.g., Lightbown, 1984; McLaughlin, 1987). This article aims to build on such initiative asking: (a) Are there multiple theories of SLA? (b) Is it a problem? and (c) what criteria have SLA researchers used to appraise and choose between theories, and how compelling are they? Following this, consideration is given to top-down and bottom-up approaches to SLA theory construction. I conclude by advancing the modest claim that rationality in SLA therory construction is possible, in spite of insistent problems.
Optimal Matching of an Optimally Chosen Subset in Observational Studies

An algorithm is proposed for optimally matching to controls an optimally chosen subset of treated subjects. The algorithm makes three optimal decisions at once: (i) the number of treated subjects to match, (ii) the identity of the treated subjects to match, and (iii) the identity of the controls with whom they are paired. The algorithm finds an optimal assignment for an augmented distance matrix. An example from critical care medicine is considered in detail. An R-workspace is available under “supplemental materials”; it can reproduce the matches in the example.
Effect of substrate contact shape and placement on RF characteristics of 45 nm low power CMOS devices

The substrate resistance of 45 nm CMOS devices shows a strong dependence on the distance between the device edge and the substrate ring; as well as on the number of sides that the device is surrounded by the contact ring. We find that the unilateral gain is impacted by the substrate resistance (R sx ) through the gate-body capacitance feedback path at low to medium frequencies (≪ 20GHz). At mm wave frequencies, the unilateral gain is affected by the R sx through the drain-body capacitance pole, and deviates from the ideal −20dB/dec slope. The impact of substrate resistance on f T , maximum available gain, high frequency noise and power characteristics of the devices is minimal.
Congenital malformation of the central nervous system associated with genital type (type 2) herpesvirus

A newborn infant was observed in whom micrencephaly, intracranial calcification, microphthalmus, and retinal dysplasia were associated with vesicular skin lesions from which herpesvirus type 2 was recovered. The mother and infant had antibody to only the type 2 virus. The history suggests that the infant became infected with the herpesvirus transplacentally early in gestation. A previously reported case of similar malformations was also associated with herpesvirus isolation from skin lesions. These two cases, considered together, suggest that the herpesvirus has a neurotropic teratogenic potential.
Morphological study of the extrusion of secretory materials by the parotid glands of mouse and rat.

Ultrastructural changes that were interpreted as manifestations of the extrusion of secretory materials are described in acinous and striated-duct cells of parotid glands of mouse and rat; the changes appeared to be identical in both species. In acinous cells: secretion granules discharged their contents by a process in which the membrane of the secretion granule became a part of the plasma membrane of the cell; small masses of cytoplasm were separated from the remaining cytoplasm by the coalescence of numerous tiny membranous vesicles, and extruded into the lumen; vacuoles, which formed by the swelling of various pre-existent membranous structures, extruded their contents in the same manner as secretion granules. In the striated ducts the apical ends of epithelial cells, which were usually characterized by a microvillous surface, lost their microvilli and swelled, sending large bleb-like projections of cytoplasm into the lumen. The blebs were apparently separated from their cells of origin, becoming a part of the secretion of the gland.
Capillary zone electrophoresis at subzero temperatures. I. Separation of the cis and trans conformers of small peptides.

Abstract The cis-trans conformers of two dipeptides, Phe-Pro and Leu-Pro, and two opioid heptapeptides containing one or two proline residues were separated by capillary zone electrophoresis (CZE) in borate buffer at low temperatures down to −17°C. At temperatures near ambient, the relaxation time of the cis-trans isomerization is on the time-scale of minutes for the dipeptides and thus commensurate with the migration times in CZE under usual operating conditions. The conformers of both dipeptides could be separated with baseline resolution below 10°C in neat aqueous 100 mM sodium borate (pH 8.4). The conformer peaks on the electropherograms were identified by using authentic samples of the cis and trans forms of Phe-Pro and Leu-Pro that were obtained by reversed-phase HPLC at 0°C, validated by NMR spectroscopy and stored in liquid nitrogen. The interplay of the electrophoretic migration and on-column isomerization reaction in CZE of Phe-Pro under various conditions was analyzed in the light of the Damkohler number (Da). The results showed that besides employing low temperature increasing the voltage and/or decreasing the capillary length also reduce the magnitude of Da to bring about the separation of interconverting species. In this work the use of low temperature in this work was preferred due to the experimental simplicity. The separation of cis-trans conformers of two opioid heptapeptides was carried out by CZE at subzero temperatures with aqueous sodium borate containing 23% (v/v) glycerol at pH∗ 11.3 as measured with a glass electrode. The two conformers of Tyr-Pro-Phe-Asp-Val-Val-Gly-NH2 were baseline separated at −12°C and the four conformers of Tyr-Pro-Phe-Gly-Tyr-Pro-Ser-NH2 due to the presence of two peptidyl-proline bonds in the molecule, were also resolved at −12°C. From the electrophoretic mobilities, the hydrodynamic radii of the cis-trans conformers of the dipeptides Phe-Pro and Leu-Pro were estimated. In both cases, the trans isomers had 1.3 times greater Stokes radii than the cis conformers. This agrees with the observed migration order and molecular modeling results. The hydrodynamic radii of the Phe-Pro conformers were smaller than those of the Leu-Pro isomers despite the lower molecular mass of the latter. The results demonstrate that CZE is suitable for measuring certain molecular properties and suggest that the methods introduced here are applicable to the study of other systems of interconverting conformers.
Systematic comparison of a theory-based transport model with a multi-tokamak profile database

A theoretical model of flux-surface-averaged radial transport in tokamaks has been tested and calibrated against a well-documented set of temperature and density profiles from a pre-defined set of discharges from seven tokamaks. The transport theory includes neoclassical, drift/ηi, circulating electron mode, kinetic ballooning, neoclassical MHD, and resistive ballooning effects. Allowing for no explicitly adjustable free parameters, the nominal theory results are compared with experimental density and temperature profiles from the reference set of discharges from Alcator-C, ASDEX, ISX-B, TFTR, DIII-D, and JET. Profile results are also given for an additional set of six discharges including Alcator-C, ASDEX, DIII-D, TFTR, JET, and JFT-2M in addition to five TFTR discharges as part of a ρ* and β scan. Employed is a statistical model of calibration/modeling and measurement variances allowing detailed analysis of results and further calibration of the model along with a well defined procedure for setting the time dependent boundary conditions at an appropriate location just inside the inner-most "closed" magnetic flux surface.
Disease and ecology: crossroads in primate evolution

What is more significant for primate survival and behavior: a leopard stalking baboons on the African floodplain, or a pin worm crawling through the colon of a squirrel monkey? In Infectious Diseases in Primates, Nunn and Altizer argue that, although pathogens and parasites are more cryptic and less spectacular than fanged predators, they could in fact have a role equal to or greater than both predation and resources in affecting the distribution, behavior and abundance of primates. This is an innovative view compared with more traditional primate ecology, where resource competition and predation have been regarded as the overriding forces that influence primate social systems.
Cyclin D1 as a universally expressed mantle cell lymphoma-associated tumor antigen for immunotherapy

Mantle cell lymphoma (MCL) accounts for 5-10% of all non-Hodgkin lymphomas and has the worst prognosis among all lymphomas. The hallmark of MCL is a t(11;14) translocation that results in overexpression of cyclin D1 by tumor cells of virtually all patients. In this study, we examined whether cyclin D1 could be an effective tumor-associated antigen for immunotherapy. We identified cyclin D1 peptides for HLA-A(*)0201 and generated peptide-specific CD8(+) T-cell lines from HLA-A(*)0201(+) blood donors and MCL patients. These cell lines proliferated in response to cyclin D1 peptide-pulsed stimulatory cells. Moreover, the T cells efficiently lysed peptide-pulsed but not unpulsed T2 cells and autologous dendritic cells; cyclin D1(+) and HLA-A(*)0201(+) human MCL lines MINO, SP53, Jeko-1 and Granta 519; and more importantly, HLA-A(*)0201(+) primary lymphoma cells from MCL patients. No killing was observed with HLA-A(*)0201(-) primary lymphoma cells or HLA-A(*)0201(+) normal blood cells, including B cells. These results indicate that these T cells are potent cytotoxic T cells and recognize cyclin D1 peptides naturally presented by patient lymphoma cells in the context of HLA-A(*)0201 molecules. Taken together, our work identifies cyclin D1 as a potentially important antigen for immunotherapy of MCL.
Styrene inhalation toxicity studies in mice. I. Hepatotoxicity in B6C3F1 mice.

Studies were conducted to evaluate the toxic effects of shortterm repeated styrene inhalation in B6C3F1 mice. Male and female mice were exposed to 0, 125, 250, or 500 ppm styrene, 6 hr/day, for up to 14 days. Styrene toxicity was characterized by severe centrilobular hepatic necrosis and deaths after one exposure to 500 ppm or two exposures to 250 ppm. Mortality and hepatotoxicity were not increased by additional exposures, and in surviving mice, regeneration and repair of initial hepatic injury occurred in spite of continued exposure for 14 days. A marked sex difference was observed, with male mice significantly more susceptible to styrene toxicity than females. A non-linear dose response was observed where mortality in male and female mice was greater in the 250 ppm dose group than that in the 500 ppm dose group. Severe congestion and necrosis of the liver was present in moribund mice; hepatic congestion and serum alanine aminotransferase and sorbitol dehydrogenase were significantly greater in moribund animals.
Gut microbiota, intestinal permeability, obesity-induced inflammation, and liver injury.

Obesity and its metabolic complications are major health problems in the United States and worldwide, and increasing evidence implicates the microbiota in these important health issues. Indeed, it appears that the microbiota function much like a metabolic “organ,” influencing nutrient acquisition, energy homeostasis, and, ultimately, the control of body weight. Moreover, alterations in gut microbiota, increased intestinal permeability, and metabolic endotoxemia likely play a role in the development of a chronic low-grade inflammatory state in the host that contributes to the development of obesity and associated chronic metabolic diseases such as nonalcoholic fatty liver disease. Supporting these concepts are the observations that increased gut permeability, low-grade endotoxemia, and fatty liver are observed in animal models of obesity caused by either high-fat or high-fructose feeding. Consistent with these observations, germ-free mice are protected from obesity and many forms of liver injury. Last, man...
Cell-microcarrier adhesion to gas-liquid interfaces and foam.

The interaction of microcarriers, both with and without cells attached, with gas bubbles was studied. These studies consisted of qualitative microscopic observations of microcarriers with bubbles, quantitative measurements of microcarrier entrapment in foam, and quantitative measurements of the effect of bubble rupture at gas-medium interfaces. Ten different “protective additives” were evaluated for their ability to change the dynamic surface tension of the culture media and to prevent microcarrier adhesion to air bubbles during gas sparging and to prevent entrapment in the foam layer. These studies indicate that microcarriers, with and without cells, readily attach to gasmedium interfaces; yet unlike suspended cells, cells attached to microcarriers are not damaged by bubble ruptures at gas-medium interfaces. Only one surfactant was found to substantially prevent microcarrier entrapment in the foam layer; however, this surfactant was toxic to cells. No correlation was observed between surface tension and the prevention of microcarrier adhesion to gas-liquid interfaces. It is suggested that cell damage as a result of sparging in microcarrier cultures is the result of cells, attached to microcarriers, attaching to rising bubbles and then detaching from the microcarrier as this combination rises through the medium. It is further suggested that the hydrodynamic drag force of the rising microcarrier is sufficiently high to remove the bubble-attached cell from the microcarrier.
Comparison of the postoperative intraocular pressure with Betagan, Betoptic, Timoptic, Iopidine, Diamox, Pilopine Gel, and Miostat.

Abstract A randomized, masked study measuring postoperative intraocular pressure at 4, 8, and 24 hours, two to seven days, and one month after planned extracapsular cataract extraction with posterior chamber lens implantation was conducted. Seven commonly used ocular hypotensive agents and a control, given at the completion of surgery, were compared: timolol maleate (Timoptic®), levobunolol hydrochloride (Betagan®), betaxolol hydrochloride (Betoptic®), pilocarpine hydrochloride (Pilopine Gel®), carbachol (Miostat®), apraclonidine hydrochloride (Iopidine®), acetazolamide (Diamox®). There were significant differences between agents. Miostat was the most effective in controlling postoperative IOP, followed by Timoptic. Diamox, Pilopine Gel, and Betagan were equally effective. Betoptic was somewhat less effective and Iopidine was not significantly better than the control.
Exploring multiple profiles of L2 writing using multi-dimensional analysis

Abstract In this paper, we explore the application of corpus-based multi-dimensional analysis (MDA) pioneered by Biber, 1988 , Biber, 1995 , Biber, 2006 in understanding microscopic linguistic variation in an L2 writing corpus. The primary goals of our study are: (1) to identify the functional dimensions of L2 academic essays from the corpus collected for this special issue of the Journal of Second Language Writing, and (2) to analyze linguistic variation in the corpus across parameters of time and average assessment scores (in language, vocabulary, and total average score). The corpus was tagged for part-of-speech and additional semantic categories (e.g., semantic categories of verbs and nouns) using the Biber tagger ( Biber, 2006 ). Rates of occurrence were computed for over 80 linguistic features across 209 essays based on tag counts for each text. The values of these variables were then subjected to an exploratory factor analysis. A total of four functional dimensions were identified and interpreted. These are: (1) Involved vs. Informational Focus, (2) Addressee-Focused Description vs. Personal Narrative, (3) Simplified vs. Elaborated Description, and (4) Personal Opinion vs. Impersonal Evaluation/Assessment. Overall, our study shows a successful application of MDA on a micro-level producing a range of functional profiles along different parameters in L2 writing.
On steady state availability of a system with lognormal repair time

Assuming two-parameter lognormal distribution for repair times, statistical inference for the steady state availability of a system is considered. For the failure time distribution, weibull, gamma, and lognormal distributions were considered. Using the generalized p-value approach, we propose confidence intervals and exact tests for the steady state availability of a system. A couple of examples are given to illustrate the proposed procedures.
Thermoelectric Generators for Automotive Waste Heat Recovery Systems Part II: Parametric Evaluation and Topological Studies

A comprehensive numerical model has been proposed to model thermoelectric generators (TEGs) for automotive waste heat recovery. Details of the model and results from the analysis of General Motors’ prototype TEG were described in part I of the study. In part II of this study, parametric evaluations are considered to assess the influence of heat exchanger, geometry, and thermoelectric module configurations to achieve optimization of the baseline model. The computational tool is also adapted to model other topologies such as transverse and circular configurations (hexagonal and cylindrical) maintaining the same volume as the baseline TEG. Performance analysis of these different topologies and parameters is presented and compared with the baseline design.
Queries as anchors: selection by association

This paper introduces a new method for linking the world view of the search engine user community with that of the search engine itself. This new method is based on collecting and aggregating associative query trails in the form of query reformulation sessions. Those associative query trails are then used to expand the documents indexed by the search engine. Our method is shown to reduce the time spent searching the index, reduce the need to reformulate queries, and also increase the proportion of queries which fulfill the user's information need. Our work provides a mere glimpse into a new field of study by introducing new types of linking between documents and users' world views. Such links from world views have never previously been considered content that can be indexed and searched over.
A comparison of two different bronchial cuff designs and four different bronchial cuff inflation methods.

Abstract Objective: To compare directly measured pressures at the cuff/trachea interface that are associated with two different bronchial cuff designs and four different methods of bronchial cuff inflation suggested for use with one-lung ventilation. Design: In vitro study. Setting: Experimental laboratory in a university-affiliated hospital. Interventions: The bronchial cuffs of two different endotracheal tubes were inflated using one of four different methods of determining the cuff volume and pressure necessary to “just seal” the bronchus and obtain lung separation: positive-pressure test, negative-pressure test, CO2 analysis, and a new test using an anesthesia ventilator. When each method predicted the “just-seal” state, the pressure at the cuff/bronchus interface as well as cuff inflation pressure and volume were recorded. Measurements and Main Results: Although the new test was incompatible with the bronchial blocker, the other three tests all accurately predicted lung separation with the Univent, with no significant differences in pressures exerted on the trachea. However, when used with the double-lumen tube, the new test produced significantly lower measured parameters than the other inflation methods. CO2 analysis did not reliably predict bronchial seal with the double-lumen tube. Conclusions: To achieve lung separation with the lowest pressure on the trachea, the new test is the most appropriate method for use with the double-lumen tube; however, the negative-pressure test appeared to be the easiest and fastest method for use with the bronchial blocker. Although the bronchial blocker was associated with lower pressures transmitted from the cuff to the trachea, the in vitro model cannot predict which bronchial cuff design would be superior in vivo.
Cadmium sensitivity of soybean related to efficiency in iron utilization

Abstract The comparative response of T203 (PI-56319-5-1), Hawkeye, and Williams soybean ( Glycine max (L.) Merr.) genotypes to cadmium treatment was examined. T203 (highly iron-inefficient), Williams (moderately iron-inefficient), and Hawkeye (iron-efficient) seedlings were grown for 2 weeks in sand culture amended with 0, 0.05, or 0.30 ppm Cd as CdCl 2 in the nutrient solution. Symptoms of cadmium toxicity, resembling iron deficiency chlorosis, appeared earlier and were more severe in the iron-inefficient than in the iron-efficient plants. Foliar concentrations of cadmium were similar in all genotypes. However, the high cadmium treatment reduced the iron concentration of T203 shoots by 55% and that of Williams and Hawkeye by 20 and 14%, respectively. The high cadmium treatment also reduced the zinc content of T203 plants and had a negative impact on the stem height, leaf area, and dry matter accumulation of all three cultivars. In addition, diffusive resistance was significantly increased and transpiration significantly decreased with cadmium treatment. Generally, the magnitude of the cadmium effect was greatest in T203, followed by Williams and then Hawkeye soybeans. These results support the hypothesis that the response of T203, Williams, and Hawkeye soybeans to cadmium is dependent, directly or indirectly, on their relative ability to utilize iron efficiently.
PRIMARY AND SECONDARY MOTIVATIONAL PROPERTIES OF A LIGHT STIMULUS

Rats were trained on a continuous reward schedule (CRF) in a 2-bar test box with or without light contingency associated with food reward. During extinction trials with the light contingency presented on CRF, the light contingency was shown to facilitate extinction on the basis of response totals (energizing effect) and percentage of responses on the reward bar (directional effect). For these extinction trials, no evidence was obtained for secondary reinforcing (Sr) properties of the light contingency. However, a second experiment found a strong Sr energizing effect when the light contingency was presented on a FR-5 or FR-10 schedule during extinction trials. These energizing effects were also obtained for rats trained without the light contingency, but to a lesser degree than for rats trained with the light contingency. Presentation of the light contingency on a FR schedule during extinction trials also resulted in a strong directional effect for all groups, regardless of the training condition. A modera...
Strand Exchange Protein 1 (Sep1) from Saccharomyces cerevisiae Does Not Promote Branch Migration in Vitro

Abstract It has been shown in vitro thatSaccharomyces cerevisiae strand exchange protein 1 (Sep1) promotes the transfer of one strand of a linear duplex DNA to a homologous single-stranded DNA circle. Sep1 also has an exonuclease active on DNA and RNA. By using exonuclease III-treated linear duplex DNA with various lengths of single-stranded tail as well as Ca2+ to inhibit the exonuclease activity of Sep1, we show that the processivity of exonuclease activity of Sep1 is greater than previously reported. The results in this work also demonstrate that the joint molecule between the linear duplex and single-stranded circle observed from the Sep1-promoted strand transfer reaction is just the pairing between the long single-stranded tail of the linear duplex DNA (generated by the exonuclease activity of Sep1) and the single-stranded circular DNA. When a synthetic Holliday junction was used as substrate, branch migration facilitated by Sep1 could not be detected. Finally, using electron microscopy no α-structure, a joint molecule with displaced single-stranded DNA tail that indicates branch migration could be observed. The results imply that Sep1 cannot promote branch migration in vitro. Further investigation is needed to determine the role of Sep1 in recombination in vivo.
Geometrical Rectification Of Spin-Scan Images From Pioneer 11

Images of Saturn received from Pioneer 11 suffer from geometrical distortions due to the curvilinear scan lines and the unequal sampling intervals in orthogonal directions, which are inherent in spin-scan imaging. In this paper we discuss geometrical image rectification by polynomial transformation based on control points. Factors that affect the accuracy of reconstruction are shown to include the spatial distribution and spatial density of control points and the order of the polynomial distortion model. A computer implementation of the technique is described.
Wrinkle-resistant cotton by photoinitiated reaction with glycidyl methacrylate followed by crosslinking reactions

A wrinkle-resistant cotton fabric was produced by photoinitiated free-radical reaction of a glycidyl methacrylate monomer from a methanol-water solution to form a poly(glycidyl methacrylate) copolymer, followed by crosslinking reactions of oxirane groups of the copolymer with cellulose. The product had increased conditioned and wet recovery angles and retained breaking and tearing strengths and stiffness values in the ranges normally obtained for wrinkle-resistant cottons. The effects of these reactions on the fiber structure were determined by transmission electron microscopy. The modified fibers were resistant to dissolution in cupriethylenediamine dihydroxide.
Removal of GC background interferences from reagents used in fumigant analysis.

Description des protocoles d'elimination des interferences lors du dosage des fumigants dans les cereales et derives : utilisation de l'azote pour eliminer les contaminants volatils dans l'eau desionisee, l'acide phosphorique a 10 % dans l'eau, la glycerine a 30 % dans l'eau. Le trimethyl-2,2,4-pentane est elimine par chromatographie sur albumine, l'acetone est purifiee par partition liquide-liquide suivie d'une redistillation azeotrope
The effective size of annual plant populations: the interaction of a seed bank with fluctuating population size in maintaining genetic variation.

Abstract: Many annual plant populations undergo dramatic fluctuations in size. Such fluctuations can result in the loss of genetic variability. Here I formalize the potential for a seed bank to buffer against such genetic loss. The average time to seed germination (T) defines the generation time of “annuals” with a seed bank, and assuming random seed germination, I show that, under otherwise ideal conditions, a population’s effective size (Ne) equals NT, where N is the number of adult plants. This result supports the general principle that lengthening the prereproductive period increases Ne. When adult numbers vary, Ne at any time depends on N and on the numbers contributing to the seed bank in previous seasons. Averaging these effects over time gives \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \usepackage[...
In-flight radiometric calibration of the airborne visible/infrared imaging spectrometer (AVIRIS)

A reflectance-based method was used to provide an analysis of the in-flight radiometric performance of AVIRIS. Field spectral reflectance measurements of the surface and extinction measurements of the atmosphere using solar radiation were used as input to atmospheric radiative transfer calculations. Five separate codes were used in the analysis. Four include multiple scattering, and the computed radiances from these for flight conditions were in good agreement. Code-generated radiances were compared with AVIRIS-predicted radiances based on two laboratory calibrations (pre- and post-season of flight) for a uniform highly reflecting natural dry lake target. For one spectrometer (C), the pre- and post-season calibration factors were found to give identical results, and to be in agreement with the atmospheric models that include multiple scattering. This positive result validates the field and laboratory calibration technique. Results for the other spectrometers (A, B and D) were widely at variance with the models no matter which calibration factors were used. Potential causes of these discrepancies are discussed.
Selection for linkage modification. I. Random mating populations.

Abstract The diploid system with chromosomes MAB, MAb, MaB and Mab is at equilibrium under selection and recombination between A a and B b loci. The M locus controls this recombination. Using local analysis near the original equilibrium, the fate of a selectively neutral recombination modifying allele ‘m’ introduced at the ‘M’ locus is investigated in the cases where the selective regimes are additive, multiplicative and symmetric. It is found that if initially there is linkage disequilibrium, ‘m’ will increase if it produces tighter linkage between the other two loci. The existence of epistasis, either additive or multiplicative, is shown not to be sufficient for recombination to be modified at a geometric rate.
Highly conductive metallomacrocyclic assemblies. Synthetic approaches to molecular metals with variable band-filling

Abstract The enforced cofacial structure of the polymer [Si(Pc)O]n has been employed to introduce new oxidation states in phthalocyanine molecular metals. Thus, oxidative electrochemical techniques have produced materials with doping levels as high as {[Si(Pc)O](BF4)0.50}n, {[Si(Pc)O] (p-toluene-sulfonate)0.85}n and {[Si(Pc)O](SO4)0.09}n. Controlled potential coulometry and X-ray diffraction studies of the [Si(Pc)O]n/BF4− system suggest that ‘break-in’ phenomena have a structural basis (orthorhombic → tetragonal) and that doping is relatively homogeneous. Optical, magnetic, and charge transport properties of the {[Si(Pc)O](BF)4y}n series are reported as a function of y. Electrochemical techniques have also been employed to synthesize partially reduced polymers such as {(Et4N)0.25[Si(Pc)O]}n and {[Li0.25[Si(Pc)O]}n. Incremental doping of [Si(Pc)O]n with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) produces materials with doping levels as high as {[Si(Pc)O]DDQy}n, y = 0.91. Optical and charge transport measurements show that as y is progressively increased, the polymer is transformed from a filled band insulator (y = 0.00), to a molecular metal (y ≈ 0.30 – 0.50), to an integral oxidation state Mott insulator (y ⪆ 0.90) .
Test for nonreciprocal circular birefringence in YBa 2 Cu 3 O 7 thin films as evidence for broken time-reversal symmetry

We have measured the amount of nonreciprocal circular birefringence of 50 to 800 \AA{} ${\mathrm{YBa}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{7}$ films in transmission with a 15-\ensuremath{\mu}m beam diameter. A novel instrument with a sensitivity of 2 \ensuremath{\mu}rad for nonreciprocal phase shifts was developed by modifying a fiber-optic gyroscope. It is insensitive to reciprocal phase shifts. We observed no nonreciprocal phase shifts in any samples.
Cointegration, error-correction, and joint efficiency in forward and futures markets for major foreign currencies

Abstract The paper employs cointegration and the associated error-correction model to examine the weak-form joint efficiency in forward and futures markets for the British pound, the German mark, the Japanese yen, the Canadian dollar, and the Swiss franc. The paper utilizes high frequency daily data on forward and futures prices of each currency for the period December 1, 1987 to October 16, 1989. The empirical findings, based upon the DW and the ADF tests in conjunction with the estimates of error-correction models, suggest that the forward and the futures markets for the British pound, the Japanese yen, and the Swiss franc are jointly efficient at the 1% level of significance. In contrast, the markets for the German mark and the Canadian dollar are found to be jointly weak-form inefficient at all conventional levels of significance.
Bimanual isometric force control: Asymmetry and coordination evidence post stroke

Abstract Objective This study determined the nature of bimanual deficits during visually-guided isometric force production in chronic stroke. Methods Stroke survivors and age-matched controls performed bimanual isometric wrist/finger extension contractions for 20 s to target submaximal force levels. Force asymmetry was indexed by the proportion of force contributed by the impaired hand to total force. Force coordination was determined by computing time-series cross-correlations and time-lag between force outputs of both hands. Results The stroke group demonstrated greater asymmetry and reduced coordination in force produced by each hand. The extent of asymmetry in the force magnitude remained constant across the three submaximal force levels in both groups. Bimanual force coordination increased at higher forces in controls but not in stroke. Finally, the less-impaired hand forces time-lagged the impaired hand. Conclusions Bimanual motor impairments in chronic stroke are characterized by increased asymmetry and reduced coordination between individual hand forces. Distinct control mechanisms are involved in the production and coordination of forces following stroke. Significance An implication involves rehabilitation protocols that emphasize bimanual coordination for training the hands to produce symmetric forces that are temporally coordinated.
Responses of host motor and sensory neurons to a neural tube implant in amputated chick limbs.

Abstract The right wingbuds of state 23–25 chick embryos were amputated at the future elbow region and a segment of 2-day neural tube was implanted longitudinally into the limb stump of experimental embryos to induce limb regeneration. Control embryos had no implant in the amputated limb stump. To analyze effects of the neural tube implant (NTI) upon the host nervous system, quantitative determinations were made of the peripheral limb field (PLF), dorsal root ganglia (DRG) and spinal cord lateral motor column (LMC) of the amputated side for comparison with similar determinations of the unamputated side in all embryos. The PLF was estimated by determining the area of the skeletal elements of the amputated and unamputated limb of each embryo. The size of the DRG was estimated by determining the sectional-profile area of a pair of ganglia; the LMC was determined by counting the neurons on both sides of a single spinal cord segment. The PLF was less on the amputated than on the unamputated side but was significantly greater in amputated limbs that received a NTI. The size of the DRG was positively correlated with the size of the PLF in all groups, indicating the DRG was not directly affected by the NTI but did respond to target structures. The number of neurons in the LMC was not positively correlated with the PLF and was not reduced by limb amputation in embryos with a NTI. The data suggest that the NTI may have protected host spinal cord cells from the induced-cell death expected to follow limb amputation; perhaps the implant produces a neuronal survival factor.
Pathogenicity of the Facultative Parasite, Chroniodiplogaster aerivora (Cobb) (Rhabditida: Diplogasteridae) to Corn Earworm (Helicoverpa zea [Boddie]) (Lepidoptera: Noctuidae)

Abstract Corn earworm pupae (Helicoverpa zea [Boddie]) were found naturally infected by Chroniodiplogaster aerivora (Cobb) (Rhabditida: Diplogasteridae) in sandy soil in a corn field in Little River Co., Arkansas, in July 1990. Six H. zea pupae of 481 examined (1.25%) were infected with the nematode. The soil was dry and hot during the pupal period of the host. This is the second report of H. zea as a natural host for diplogasterids. In laboratory bioassays mixed stages of C. aerivora killed low (12%) but significant numbers of Galleria mellonella (L.) larvae. Significantly more H. zea larvae died after exposure to 500 mixed stages/larva of C. aerivora (92.5%) than died in the controls (25%) in a bioassay. In a subsequent bioassay comparing the pathogenicity of Steinernema carpocapsae (Weiser), Heterorhabditis bacteriophora Poinar, and C. aerivora to H. zea, S. carpocapsae, and H. bacteriophora caused significantly higher mortality than C. aerivora (80, 90, and 6.25% mean mortality, respectively). Weakened or stressed H. zea appeared to be more susceptible to C. aerivora. Most mortality in both G. mellonella and H. zea exposed to C. aerivora occurred 7 or more days post-treatment. Nematodes frequently penetrated into the hemocoel through the hindgut.
Comparison of Luteolytic Potencies of Aminoglutethimide Enantiomers in the Rabbit and Rat

The luteolytic potency of D- and L-aminoglutethimide (D- and L-AG) was compared in in vivo assays in the rat and rabbit. By assay of plasma progesterone depletion in the rabbit, the potency of L-AG relative to D-AG was 0.21. By the plasma procedure in the rat, the relative potencies of L-AG and of the racemic mixture to D-AG were 0.04 and 0.37, respectively. By the ovarian progesterone depletion method, the L-form had very little activity and the DL-mixture was half as active as the D-isomer. Thus, in both species, almost all of the activity of the racemic mixture results from the content of D-AG. Interpretation of paradoxical data implies that in the rat, L-AG may inhibit liver degradation of progesterone at levels which do not modify secretion from the corpus luteum.
Critical assessment of how to study addiction and its treatment: Human and non-human animal models

Laboratory models, both animal and human, have made enormous contributions to our understanding of addiction. For addictive disorders, animal models have the great advantage of possessing both face validity and a significant degree of predictive validity, already demonstrated. Another important advantage to this field is the ability of reciprocal interplay between preclinical and clinical experiments. These models have made important contributions to the development of medications to treat addictive disorders and will likely result in even more advances in the future. Human laboratory models have gone beyond data obtained from patient histories and enabled investigators to make direct observations of human drug self-administration and test the effects of putative medications on this behavior. This review examines in detail some animal and human models that have led not only to important theories of addiction mechanisms but also to medications shown to be effective in the clinic.
Measuring nutritional status in children with chronic kidney disease

Children with chronic kidney disease (CKD) are at risk of protein-energy malnutrition. Existing clinical practice guidelines recognize this and recommend specific methods to assess nutritional status in patients with CKD. This review summarizes the methods for nutritional assessment currently recommended in the United States for children with CKD and details the strengths and limitations of these techniques in the clinical setting. Dietary assessment, serum albumin, height, estimated dry weight, weight/height index, upper arm anthropometry, head circumference, and the protein equivalent of nitrogen appearance are reviewed. We also describe methods for body-composition assessment, such as dual-energy X-ray absorptiometry, bioelectrical impedance analysis (BIA), total body potassium, densitometry, and in vivo neutron activation analysis, pointing out some advantages and disadvantages of each. In CKD, fluid overload is the most important factor leading to misinterpretation of nutritional assessment measures. Abnormalities in the distribution of fat and lean tissue may also compromise the interpretation of some anthropometric measures. In addition, metabolic abnormalities may influence the results obtained by some techniques. Issues specific to evaluating nutritional status in the pediatric population are also discussed, including normalization of nutritional measures to body size and sexual maturity. We stress the importance of expressing body-composition measures relative to height in a population in whom short stature is highly prevalent.