cssi/SciSciGPT-SciSciNet huggingface dataset:
Water soluble pentacene

A water soluble pentacene, potassium 3,3′-(pentacene-6,13-diylbis(sulfanediyl))dipropanoate (4), has been synthesized and characterized. The synthesis of 4 is straightforward and scalable, and its isolation does not require time consuming chromatographic separations. UV-vis spectra in several solvents indicate an optical HOMO–LUMO gap of approximately 1.91–1.97 eV. Water soluble pentacene 4 is long-lived in the solution phase and in the solid state. Because it forms stable solutions, inks based on 4 have been formulated and printed onto paper and flexible plastic using an unmodified commercial ink-jet printer. A bi-layer photovoltaic cell using 4 as donor and [60]fullerene as acceptor was fabricated and shown to be active. The crystal structure of the pentacene diacid precursor to water soluble pentacene 4 has been solved and shows a parallel displaced arrangement of pentacene rings, indicative of stabilizing π–π stacking interactions. DFT modeling for 4, however, suggests an unusual, low energy conformation in which both potassium carboxylate moieties are located on the same face (syn) of the pentacene π system. Likewise, calculated two-molecule stacks of 4 suggest a crystal packing arrangement in which potassium carboxylate moieties are intercalated between adjacent pentacene rings.
Synergy assessed by checkerboard a critical analysis

The checkerboard dilution test is widely used for evaluation of in vitro synergy for multiple drugs, although problems in performance, standardization, and interpretation have been noted. A major problem inherent in this commonly used method is the use of twofold dilutions for the antibiotic concentrations. We evaluated an alternative method proposed by Horrevorts and colleagues that preserved the twofold dilution scheme. Giant checkerboards were constructed from a series of component checkerboards using rifampin and minocycline against Staphylococcus aureus. We found that this method improved the stability of the fractional inhibitory concentration (FIC) indices, but required substantially more labor and generated other problems. FIC interpretation and calculation remained compromised by the twofold dilution scheme. We have analyzed the theoretical basis of the checkerboard and its FIC calculation and conclude that the twofold dilution with its exponential increase in dilutions makes this method of synergy evaluation inherently unstable. The principle of examining growth at multiple dilutions of combined antibiotics is valid for assessment of synergy, but newer methods need to be devised.
Volume changes during glycerol absorption by regenerated cellulose

The volume changes which a cellulose gel swollen with water undergoes on immersion in aqueous glycerol solutions containing from 10–80% glycerol have been studied. If the gel is considered from the standpoint of dry cellulose plus glycerol solution, the volume contraction (compared with the theoretical sum of the volumes of the components) is less than 1% over the entire range of glycerol concentrations studied. When the unsoftened gel film is immersed in softener solution, the volume increase of the gel is small (1–5%, corresponding to a concentration of 10–60% glycerol in the softener bath). It may therefore be concluded that, except possibly at very high glycerol contents, the internal volume relationships for softened and unsoftened gel film are the same.
Child Discipline in African American Families A Study of Patterns and Context

Child discipline is a fundamental component of child rearing in African American families. The authors examined the patterns and context of child disciplinary strategies used by African American parents to address repeated misbehavior in children. Results indicated that African American parents use a variety of disciplinary strategies to address recurring misbehavior. These disciplinary strategies represented a hierarchal pattern. Implications for counselor training and practice are presented.
Differentiating the undifferentiated: immunohistochemical profile of medullary carcinoma of the colon with an emphasis on intestinal differentiation

Undifferentiated or medullary carcinoma is characterized by its distinct histologic appearance and relatively better prognosis compared to poorly differentiated colonic carcinoma. These 2 entities may be difficult to differentiate by light microscopy alone. Only limited immunohistochemical studies investigating medullary carcinoma have been reported. These studies suggest a loss of intestinal differentiation, exemplified by a high percentage of CDX2 negativity. Our aim was to further characterize the immunohistochemical profile of medullary carcinoma, with particular emphasis on intestinal markers. Paraffin blocks from 16 cases of medullary carcinoma and 33 cases of poorly differentiated colonic carcinoma were retrieved, and tissue microarrays were constructed and stained with an immunohistochemical panel including CDX2, CK7, CK20, p53, intestinal trefoil factor 3, chromogranin, synaptophysin, MLH-1, MUC-1, MUC-2, and calretinin. A significantly higher proportion of medullary carcinomas, as opposed to poorly differentiated colonic carcinomas, showed loss of staining for MLH-1 and for the intestinal transcription factor CDX2, in accordance with previous studies. MLH-1 staining was present in only 21% of medullary carcinoma cases compared with 60% of the poorly differentiated colonic carcinoma cases (P = .02), whereas CDX2 was positive in 19% of medullary carcinomas and 55% of poorly differentiated colonic carcinomas (P = .03). Interestingly, calretinin staining was strongly positive in 73% of medullary carcinomas compared to only 12% of poorly differentiated colonic carcinomas (P < .0001). Evidence of intestinal differentiation by MUC-1, MUC-2, and TFF-3 staining was seen in 67%, 60%, and 53% of the medullary carcinomas, respectively. These 3 markers were frequently positive in many of the CDX2-negative medullary carcinoma cases. Medullary carcinoma of the colon retains a significant degree of intestinal differentiation as evidenced by its high percentage of staining for MUC-1, MUC-2, and TFF-3. Calretinin, MLH-1, and CDX2 may help to differentiate medullary carcinoma from poorly differentiated colonic carcinoma of the colon.
Cross-Talk between Estrogen Receptor and Growth Factor Pathways as a Molecular Target for Overcoming Endocrine Resistance

Introduced more than 100 years ago, endocrine therapy is still the most important systemic therapy for all stages of estrogen receptor (ER) -positive breast tumors. A major clinical problem limiting the usefulness of this therapy is tumor resistance, either de novo or acquired during the course of the treatment. Relatively new discoveries emphasize the complexity of ER signaling and its multiple regulatory interactions with growth factor and other kinase signaling pathways. Both genomic (nuclear) and nongenomic (membrane and cytoplasmic) ER activities contribute to this intimate cross-talk, which is probably a fundamental factor in endocrine resistance. New targeted therapies, especially against the epidermal growth factor receptor/HER-2 pathway, should be carefully evaluated in more (bio)logical strategies to enable them to be exploited appropriately. A strategy of combining endocrine therapy (particularly tamoxifen) with these inhibitors, to circumvent de novo and acquired resistance, will be discussed. We will also emphasize open questions and future challenges in the dynamic research field of molecular ER biology from the endocrine therapy perspective.
Developing self-control in preschool children through correspondence training

Twelve inner-city preschool children experienced one of two training procedures designed to establish correspondence between their verbalizations about behavioral self-control and execution of a self-control task. The children played the Scarecrow Game which involved the prolonged extension of their arms at their sides. The game is an analog of a “tolerance” type self-control situation. Group 1 experienced a saying (intention) then doing sequence. Group 2 was trained via a doing then saying (reporting) sequence. The experiment was conducted in three phases over 22 days. Both groups showed an increase over baseline in verbalization and play with the game, although reinforcement of verbalization alone did not produce an increase in self-control activity. A significant increase in correspondence did occur in both groups when a snack was delivered contingent upon the matching of verbal report to actual performance. In addition, the level of correspondence exhibited by the say-do group exceeded that of the do-say group.
Cartilage link protein 1 (Crtl1), an extracellular matrix component playing an important role in heart development.

Abstract To expand our insight into cardiac development, a comparative DNA microarray analysis was performed using tissues from the atrioventricular junction (AVJ) and ventricular chambers of mouse hearts at embryonic day (ED) 10.5–11.0. This comparison revealed differential expression of approximately 200 genes, including cartilage link protein 1 (Crtl1). Crtl1 stabilizes the interaction between hyaluronan (HA) and versican, two extracellular matrix components essential for cardiac development. Immunohistochemical studies showed that, initially, Crtl1, versican, and HA are co-expressed in the endocardial lining of the heart, and in the endocardially derived mesenchyme of the AVJ and outflow tract (OFT). At later stages, this co-expression becomes restricted to discrete populations of endocardially derived mesenchyme. Histological analysis of the Crtl1-deficient mouse revealed a spectrum of cardiac malformations, including AV septal and myocardial defects, while expression studies showed a significant reduction in versican levels. Subsequent analysis of the hdf mouse, which carries an insertional mutation in the versican gene (CSPG2), demonstrated that haploinsufficient versican mice display septal defects resembling those seen in Crtl1−/− embryos, suggesting that reduced versican expression may contribute to a subset of the cardiac abnormalities observed in the Crtl1−/− mouse. Combined, these findings establish an important role for Crtl1 in heart development.
Renal imaging: duplex ultrasound, computed tomography angiography, magnetic resonance angiography, and angiography

Renal artery stenosis (RAS) is one of the most common causes of severe hypertension (approximately 1-5% of all patients with hypertension). Presently, there is no universally accepted screening test for RAS. However, most clinicians use renal duplex ultrasound (RDU) imaging; while others use magnetic resonance angiography (MRA) or contrast computed tomography angiography in selected patients. This review will highlight various imaging modalities and discuss the pros and cons of each.
Modulation of cardiac Ca2+ channels by IGF1.

Abstract Although there are several reports on the regulation of neuronal and skeletal muscle voltage-sensitive calcium channels by IGF1, the effects of short-term IGF1 exposure on cardiac Ca 2+ channels have not been described. We measured the activity of nitrendipine-sensitive Ca 2+ channels of intact cardiac myocytes in the presence of IGF1 by monitoring unidirectional Mn 2+ influx measured as the quench of cytosolic fura-2 in electrically stimulated or K + -depolarized cells. Maximal channel activation was observed after 10 min of preincubation with IGF1, which gave an increase of 216 +/− 25%. Treatment with the protein kinase C inhibitors bisindolylmaleimide I and chelerythrine mimicked the augmentation effect of IGF1, whereas PMA blocked enhancement of Mn 2+ influx by IGF1. These results demonstrate that acute IGF1 augments dihydropyridine-sensitive sarcolemmal Ca 2+ channel activity and that protein kinase C may contribute to the regulation of cardiac Ca 2+ channels by IGF1.
Comments on “Solubility of Ethyl Maltol in Aqueous Ethanol Mixtures” (Liu, B.-S.; Liu, R.-J.; Hu, Y.-Q.; Hu, Q.-F. J. Chem. Eng. Data 2008, 53, 2712−2714)

where xm, x1, and x2 are the numerical values of the solubility of the solute in the mixture and solvents 1 and 2, respectively; f1 and f2 are the volume (mass or mole) fractions of solvents 1 and 2 in the mixture in the absence of the solute; and Si represent the model constants. The model could be rearranged to eq 2 by replacing f2 with 1 - f1 and further simplified as 2
Glossopteris Discovered in West Antarctica

Leaf impressions from the Polarstar Formation in the northern Ellsworth Mountains are the first Glossopteris and the oldest identifiable plant fossils reported from West Antarctica. Their occurrence in a thick, probably marine, geosynclinal sequence in close association with coals and probable glacial deposits increases the similarity between the late Paleozoic history of Antarctica and the other southern continents.
Glucose metabolism in Neurospora is altered by heat shock and by disruption of HSP30

We compared the metabolism of [1-13C]glucose by wild type cells of Neurospora crassa at normal growth temperature and at heat shock temperatures, using nuclear magnetic resonance analysis of cell extracts. High temperature led to increased incorporation of 13C into trehalose, relative to all other metabolites, and there was undetectable synthesis of glycerol, which was a prominent metabolite of glucose at normal temperature (30 degrees C). Heat shock strongly reduced formation of tricarboxylic acid cycle intermediates, approximately 10-fold, and mannitol synthesis was severely depressed at 46 degrees C, but only moderately reduced at 45 degrees C. A mutant strain of N. crassa that lacks the small alpha-crystallin-related heat shock protein, Hsp30, shows poor survival during heat shock on a nutrient medium with restricted glucose. An analysis of glucose metabolism of this strain showed that, unlike the wild type strain, Hsp30-deficient cells may accumulate unphosphorylated glucose at high temperature. This suggestion that glucose-phosphorylating hexokinase activity might be depressed in mutant cells led us to compare hexokinase activity in the two strains at high temperature. Hexokinase was reduced more than 35% in the mutant cell extracts, relative to wild type extracts. alpha-Crystallin and an Hsp30-enriched preparation protected purified hexokinase from thermal inactivation in vitro, supporting the proposal that Hsp30 may directly stabilize hexokinase in vivo during heat shock.
Root niche partitioning among grasses, saplings, and trees measured using a tracer technique.

Niche partitioning of resources by plants is believed to be a fundamental aspect of plant coexistence and biogeochemical cycles; however, measurements of the timing and location of resource use are often lacking because of the difficulties of belowground research. To measure niche partitioning of soil water by grasses, planted saplings, and trees in a mesic savanna (Kruger National Park, South Africa), we injected deuterium oxide into 102,000 points in 15, 154-m2 plots randomly assigned to one of five depths (0–120 cm) and one of three time periods during the 2008/2009 growing season. Grasses, saplings and trees all demonstrated an exponential decline in water uptake early in the season when resources were abundant. Later in the season, when resources were scarce, grasses continued to extract the most water from the shallowest soil depths (5 cm), but saplings and trees shifted water uptake to deeper depths (30–60 cm). Saplings, in particular, rapidly established roots to at least 1 m and used these deep roots to a greater extent than grasses or trees. Helping to resolve contradictory observations of the relative importance of deep and shallow roots, our results showed that grasses, saplings and trees all extract the most water from shallow soils when it is available but that woody plants can rapidly shift water uptake to deeper soils when resources are scarce. Results highlight the importance of temporal changes in water uptake and the problems with inferring spatial and temporal partitioning of soil water uptake from root biomass measurements alone.
On the hydroxyl radical formation in the reaction between hydrogen peroxide and biologically generated chromium(V) species.

Electron spin resonance (ESR) measurements on solutions and isolated powders provide direct evidence for the involvement of Cr(V) species in the reduction of Cr(VI) by NAD(P)H. ESR analysis of an isolated Cr(V)-NAD(P)H solid yields g∥ = 1.9831 and g⊥ = 1.9772, indicating that the unpaired electron occupies the dz2 orbital of the Cr(V) ion, with square-pyramidal geometry. Addition of hydrogen peroxide (H2O2) to the NAD(P)H-Cr(VI) reaction mixtures suppresses the Cr(V) species and generates hydroxyl (.OH) radicals. The .OH radicals were detected via ESR spin trapping, employing 5,5-dimethyl-1-pyrroline-N-oxide and α-(4-pyridyl-1-oxide)-N-tert-butylnitrone as spin traps. The dependence of Cr(V) and .OH radical formation on the H2O2 and Cr(VI) concentrations indicates that the Cr(V) species react with H2O2 to generate the .OH radicals. Similar results were obtained by using various diols (arabinose, cellobiose, FAD, fructose, glyceraldehyde, ribose, and tartaric acid), α-hydroxycarboxylic acids, and glutathione. Investigations with superoxide dismutase showed no significant participation of O2− in the generation of .OH radicals. These results thus indicate that the Cr(V) complexes, produced in the reduction of Cr(VI) by cellular reductants, react with H2O2 to generate .OH radicals, which might be the initiators of the primary events in the Cr(VI) cytotoxicity.
Hilbert Modular Varieties of Galois Quartic Fields

Abstract Letkbe a totally real number field of degreenoverQwith ring of integers O k. The Hilbert modular variety ofkis a desingularization of the (natural) compactification of PSL2( O k)\ H n. This paper focuses on Hilbert modular varieties of Galois quartic fields containing units of norm −1. The main result is that each of these varieties has arithmetic genus greater than one and hence is not rational.
A Review of the Current Status of Radiation Effects in Solid Nuclear Waste Forms

The current status of radiation effects in solid nuclear waste forms is reviewed. The general nature of radiation effects and the simulation techniques used are briefly discussed. Recently reported data on radiation effects are presented and discussed, and those areas requiring further theoretical or experimental study are identified.
Design and Optimization of an Aluminum Nitride Sublimation Growth System

In this paper, an integrated model considering induction heating, heat transfer, growth kinetics and thermo-elastic stress has been developed to study temperature distribution in the growth system, crystal shape and stress distribution in the asgrown aluminum nitride (AIN) crystal. The electromagnetic field and induction heat generation are calculated by the Maxwell equations. Transient temperature distribution in the growth chamber is simulated by energy accounting for conduction/radiation within and between various components. To reduce thermal stress and dislocation, a growth method to enlarge the ingot diameter from a smaller seed and maintain low thermal stress in the crystal has been proposed. The thermo-elastic stress fields have been calculated for several designed temperature profiles along the crucible inner wall and stress distribution has been correlated to dislocation density distribution.Copyright © 2003 by ASME
Corn residue, tillage, and nitrogen rate effects on soil carbon and nutrient stocks in Illinois

Abstract Removal of crop residues for use as ethanol production feedstock might deplete soil carbon and nutrient pools in site- and management-specific ways. We investigated the effect of residue removal (RR), tillage (T), and N fertilizer rate (Nr) after five years of continuous corn (Zea mays L.) on total soil carbon (TC) and nutrient stocks at four sites within Illinois. The experimental design was a split–split plot arrangement of treatments in a randomized complete block design with four replications, and all treatments remained in the same place each year. Main plots consist of one of three levels of corn residue removal (RR: full, partial, and none); split plots were two tillage systems (T: chisel tilled and no-till) and split–split plots were four N fertilizer rates (Nr: 67, 134, 201, and 268 kg N ha− 1). The highest TC stocks were found under no-till without residue removal; removing any residue under no-till lowered TC to the levels found under chisel tillage. Removing residue in tilled soils produced higher TC values similar to the levels found with no residue removal and no-till. Residue removal tended to lower P and lowered K and EC in the surface 15 cm soil. Tillage decreased the N and K stocks in the surface soil. Increasing the rate of N fertilizer lowered P, K, and pH, generally in an increasing, curvilinear manner, but the response of EC was concave, increasing at the highest N rate used. These responses were closely related to corn grain yields, indicating that the amount of nutrient removed by harvest of grain and residue and the amount of residue retained after harvest affect TC and nutrient stocks in Illinois soils. This information will help producers and policy makers to make better decisions regarding the feasibility of harvesting corn residue, and on agronomic practices that might accompany residue removal in order to prevent soil nutrient depletion.
Computer-assisted detection of pulmonary embolism

In this study, a computerized method for detection of pulmonary embolism in spiral CT angiography was developed. The method is based on segmentation of pulmonary vessels to limit the search space for thrombi. Several three-dimensional image features such as local contrast, second derivatives, and distance to the vessel wall were employed for detection of thrombi and for elimination of false positives. Volume rendering was applied for display of detection results. Preliminary results based on several clinical data show the potential of our method.
Cholinergic neurons in the rat central nervous system demonstrated by in situ hybridization of choline acetyltransferase mRNA.

Abstract Digoxigenin-labeled RNA probes and in situ hybridization histochemistry were used to examine choline acetyltransferase gene expression in the rat central nervous system. Hybridization signal was present only in brain sections processed with the antisense riboprobe. The sense probe did not yield labeling, further validating the specificity of tissue reactivity. Telencephalic neurons containing the mRNA for the cholinergic synthetic enzyme were found in the caudate-putamen nucleus, nucleus accumbens, olfactory tubercule, islands of Calleja complex, medial septal nucleus, vertical and horizontal limbs of the diagonal band, substantia innominata, nucleus basalis, and nucleus of the ansa lenticularis. Some somata evincing hybridization signal were observed in the anterior amygdalar area, and an occasional such cell was seen in the basolateral and central amygdalar nuclei. Neurons in the cerebral cortex, hippocampus, and primary olfactory structures did not demonstrate hybridocytochemically detectable amounts of choline acetyltransferase mRNA. Thalamic cells were devoid of reactivity, with the exception of several neurons located primarily in the ventral two-thirds of the medial habenula. A few somata labeled with riboprobe were found in the lateral hypothalamus, caudal extension of the internal capsule, and zona incerta. Neurons in the pedunculopontine and laterodorsal tegmental nuclei were moderately reactive, whereas cells of the parabigeminal nucleus exhibited a very weak hybridization signal. No somata in the brainstem raphe nuclei, including raphe obscurus and raphe magnus, were observed to bind riboprobe. In contrast, motor neurons of the cranial nerve nuclei demonstrated relatively large amounts of choline acetyltransferase mRNA. Putative cholinergic somata in the ventral horns and intermediolateral cell columns of the spinal cord were also labeled with riboprobe, as were a few cells around the central canal. We conclude that hybridocytochemistry with digoxigenin-labeled riboprobes confirms the existence of cholinergic neurons (i.e. those that synthesize and use acetylcholine as a neurotransmitter) in most of the neural regions deduced to contain them on the basis of previous histochemical and immunocytochemical data. Notable exceptions are the cerebral cortex and hippocampus, which do not possess neurons expressing detectable levels of choline acetyltransferase mRNA.
Quantitative 13C NMR Analysis of Sequence Distributions in Poly(ethylene-co-1-hexene)

Different 13C NMR methods of determining triad distributions in two poly(ethylene-co-1-hexene) copolymers are examined using high signal-to-noise ratio 13C NMR spectra of the copolymers dissolved in deuterated 1,2,4-trichlorobenzene at 398 K. This examination includes a comparison of three integration techniques. The experimental impact of decoupler sidebands and significantly nonequal 13C NOE values are examined. A least-squares regression analysis technique for solving for triad mole fractions is tested and appears to be more reliable than two published algebraic expressions (and other expressions examined in the work reported here). The resultant triad mole fractions are compared to sequence distribution parameters expected by Bernoullian and first-order Markovian statistical models. On the basis of 13C NMR-determined average reactivity ratios, the copolymer designated sample B (5.3 mol % 1-hexene) appears to be a Bernoullian copolymer resulting from a single-site catalytic system. The copolymer design...
Double-Blind Evaluation of Oral Ribavirin (Virazole) in Experimental Influenza A Virus Infection in Volunteers

The prophylactic effectiveness of oral administration of ribavirin (1-beta-d-ribofuranosyl-1,2,4-triazole-3-carboxamide) against experimentally induced influenza A infection was evaluated in a double-blind clinical trial in normal volunteers. Fourteen men received ribavirin capsules (1,000 mg/day in four divided doses) and 15 other men received identical-appearing placebo capsules beginning 6 h after the intranasal inoculation of 3.4 log(10) 50% tissue culture infectious doses of influenza virus A/Victoria/3/75 H3N2 and continuing for 5 days after challenge. The total number of moderate-to-severe symptom scores and the total number of temperatures >/=100 degrees F (37.8 degrees C) were significantly lower in the ribavirin group compared with the placebo group. The mean quantity of virus shed in nasal wash specimens and the total number of days that there were viral titers greater than 1.0 log(10) 50% tissue culture infectious doses per ml were significantly greater in the placebo group. There was no difference between the frequencies of virus isolated or the antibody responses in the two groups. Therefore, prophylactic ribavirin ameliorated symptoms and fever indicative of moderate-to-severe illness, but had no effect on the manifestations of mild illness in response to influenza A challenge. A transient rise in total serum bilirubin occurred in 29% of the ribavirin-treated volunteers and in none of the placebo-treated volunteers.
ORAL BIOAVAILABILITY OF PENTACHLOROPHENOL FROM SOILS OF VARYING CHARACTERISTICS USING A RAT MODEL

Evidence accumulated during the last two decades suggests that only a fraction of any chemical in soil is available to organisms, and soil-related effects on bioavailability should be considered in optimizing soil remediation cleanup levels. In the current study, the absolute and relative bioavailabilities of pentachlorophenol (PCP) from freshly spiked and environmentally aged soils varying in organic carbon content, clay content, and pH were examined using a rat model. PCP is a broad-spectrum biocide widely used as a wood preservative, and thus is ubiquitous in the environment. Soils and corn oil containing equivalent levels of PCP were administered to male Sprague-Dawley rats by gavage at 2 dose levels: 100 and 200 μg/kg body weight. Equivalent doses were also given intravenously. The areas under the plasma concentration of PCP versus time curves were calculated, and absolute and relative bioavailabilities of PCP from each soil were determined. At a dose of 100 μg/kg body weight, the absolute bioavailab...
Impact of Uncertainty and Risk Aversion on Price and Order Quantity in the Newsvendor Problem

We consider a single-period inventory model in which a risk-averse retailer faces uncertain customer demand and makes a purchasing-order-quantity and a selling-price decision with the objective of maximizing expected utility. This problem is similar to the classic newsvendor problem, except: (a) the distribution of demand is a function of the selling price, which is determined by the retailer; and (b) the objective of the retailer is to maximize his/her expected utility. We consider two different ways in which price affects the distribution of demand. In the first model, we assume that a change in price affects the scale of the distribution. In the second model, a change in price only affects the location of the distribution. We present methodology by which this problem with two decision variables can be simplified by reducing it to a problem in a single variable. We show that in comparison to a risk-neutral retailer, a risk-averse retailer in the first model will charge a higher price and order less; where as, in the second model a risk-averse retailer will charge a lower price. The implications of these findings for supply-chain strategy and channel design are discussed. Our research provides a better understanding of retailers' pricing behavior that could lead to improved price contracts and channel-management policies.
A facile, general method for the preparation of fluorinated enynes

Fluorinated vinyl iodides, R1CFCFl [where R1F, CF3, Ph, (iPrO)2P(O)], couple directly with 1-alkynes in the presence of palladium and cuprous iodide in triethylamine to give excellent yields of the fluorinated enynes.
Inequalities, Democracy, and Fieldwork in the Chicago Schools of Yesterday and Today

Barriers to public discourse and participation in a democracy were central to the social reform concerns of Mead. Urban ethnographies of the last thirty years that are associated with the University of Chicago and the Chicago School contribute to this aspect of Mead's work. These ethnographies help to illuminate how extreme poverty and racism affect public discourse between groups. The Chicago tradition linked to the work of Park and Wirth has emphasized the importance of persistent inequalities and a lack of public discourse and participation rather than a symbolic interactionist approach that emphasizes the ability of people to create a place for themselves in an open, fluid world. Through field research in poor, often minority urban communities, the sociologists linked more closely to the former group have explored issues of the maintenance of patterns of extreme inequalities, the muting of public dialogue, and blockages to participation while maintaining a focus on the agency of the poor and their efforts to create their social worlds.
Dual regulation by μ, δ and κ opioid receptor agonists of K+ conductance of DRG neurons and neuroblastoma × DRG neuron hybrid F11 cells

Abstract The effects of the μ opioid receptor agonists, morphine and Tyr- d -Ala-Gly-N-methyl-Phe-Gly-ol (DAGO), the δ opioid receptor agonist, Tyr- d -Pen-Gly-Phe- d -penicillamine (DPDPE0 and the κ-opiod receptor agonist, dynorphin A-(1–13) on the whole-cell K+ currents (IK) of cultured mouse DRG neurons and neuroblastoma × DRG neuron hybrid F11 cells were studied. These opioid ligands all elicited dual effects. Low concentrations (
Grid size dependence on convergence for computation of the navier-stokes equations

Application de la methode de calcul numerique a l'ecoulement d'un fluide visqueux compressible dans une tuyere transsonique convergente-divergente
Environmental Health Disparities in Housing

The physical infrastructure and housing make human interaction possible and provide shelter. How well that infrastructure performs and which groups it serves have important implications for social equity and health. Populations in inadequate housing are more likely to have environmental diseases and injuries. Substantial disparities in housing have remained largely unchanged. Approximately 2.6 million (7.5%) non-Hispanic Blacks and 5.9 million Whites (2.8%) live in substandard housing. Segregation, lack of housing mobility, and homelessness are all associated with adverse health outcomes. Yet the experience with childhood lead poisoning in the United States has shown that housing-related disparities can be reduced. Effective interventions should be implemented to reduce environmental health disparities related to housing.
Dinámica competitiva y modelos de negocio

Este articulo introduce la nocion de la competencia en modelos de negocio, presenta el concepto de ciclo virtuoso, e ilustra como un buen diseno de modelo de negocio genera rentabilidades superiores sostenibles. El enfoque de la formulacion estrategica desde el punto de vista de los modelos de negocio ofrece una nueva perspectiva para abordar aspectos fundamentales de estrategia tales como las amenazas a la sostenibilidad de la ventaja competitiva y los riesgos y virtudes del crecimiento empresarial.
The determination of film hardness from the composite response of film and substrate to nanometer scale indentations

Two equations for determining the hardness of thin films from depth-sensing indentation data are examined. The first equation is based on an empirical fit of hardness versus indenter displacement data obtained from finite element calculations on a variety of hypothetical films. The second equation is based on a model which assumes that measured hardness is determined by the weighted average of the volume of plastically deformed material in the coating and that in the substrate. The equations are evaluated by fitting the predicted hardness versus contact depth to data obtained from titanium coatings on a sapphire substrate. Only the volume fractions model allows the data to be fitted with a single adjustable parameter, the film hardness; the finite element equation requires two thickness-dependent parameters to obtain acceptable fits. It is argued that the difficulty in applying the finite element model lies in the use of an unrealistic area function for the indenter. For real indenters, which have finite radii, the area function must appear explicitly in the final equation. This is difficult to do with the finite element approach, but is naturally incorporated into the volume fractions equation. Finally, using the volume fractions approach the hardnesses of the titanium films are found to be relatively insensitive to film thickness. Thus, the apparent increase in hardness with decreasing film thickness for the titanium films is most likely due to increased interactions between the film and substrate for the thinner films rather than to a change in the basic structure of the titanium films.
Frequency‐dependent alterations in enolase activity in Escherichia coli caused by exposure to electric and magnetic fields

Some neurochemical effects of low-intensity electric and magnetic fields have been shown to be nonlinear functions of exposure parameters. These effects occurred within narrow ranges of frequency and intensity. Previous studies on membrane-associated endpoints in cell culture preparations demonstrated changes in calcium efflux and in acetylcholinesterase activity following exposure to radiofrequency radiation, amplitude modulated (AM) at 16 and at 60 Hz, at a specific absorption rate of 0.05 W/kg. In this study, these modulation frequencies were tested for their influence on the activity of a cytoplasmic enzyme, enolase, which is being tested clinically for detection of neoplasia. Escherichia coli cultures containing a plasmid with a mammalian gene for enolase were exposed for 30 min, and cell extracts were assayed for enolase activity by measuring absorbance at 240 nm. The enolase activity in exposed cultures was compared to the activity in paired control cultures. Exposure to 147 MHz carrier waves at 0.05 W/kg, AM at 16 Hz showed enolase activity enhanced by 62%, and AM at 60 Hz showed enolase activity reduced by 28%. Similarly, exposure to 16 Hz fields alone, at 21.2 V/mrms (electric) and 97 nTrms (magnetic), showed enhancement in enolase activity by 59%, whereas exposure to 60 Hz fields alone, at 14.1 V/mrms (electric) and 65 nTrms (magnetic), showed reduction in activity by 24%. Sham exposures as well as exposure to continuous-wave 147 MHz radiation at 0.05 W/kg showed no change in enolase activity. Although the underlying basis for these field effects in the cytoplasmic compartment has not been established, differential sensitivities to 16 Hz and to 60 Hz signals provide a clear focus for additional research to determine the responsible mechanism. © 1994 Wiley-Liss, Inc.
Determinants of Agricultural Disaster Payments in the Southeastern U.S.: County Level Analysis

This paper evaluates the relevance of weather and climate data in explaining county-level crop disaster payments in Georgia. Following previous research, regional socio-economic and community data are also used to control for factors other than weather. While weather and ENSO data explain the payments well, available economic variables do not.
Order effects and memory for evidence in individual versus group decision making in auditing

Sequential processing of evidence may lead to recency effect, a potential bias in judgment. The present research seeks to extend the literature on recency effects by assessing the potential moderating influence of team work: whether group decision making moderates the severity of recency effects predicted by Hogarth and Einhorn (1992), and whether group processing influences the accuracy of, and confidence in memory for evidence. Experienced auditors from a Big-6 accounting firm made audit judgments, either individually or as groups. They were randomly assigned to one of two levels of evidence presentation order. After performing the judgment task, participants completed two evidence recognition tests. Consistent with prior findings, recency effects on judgments were observed, but only for individuals. Group judgments or audit reports were not affected by recency. Order effects, however, did not translate into different choices of audit reports, and did not persist in memories of either individuals or groups. As expected, group memory was more accurate than individual memory and groups were more confident than individuals. Overall, confidence in accurate memories was greater than in inaccurate ones. Copyright © 1999 John Wiley & Sons, Ltd.
Mutual coupling effects in infinite planar arrays of rectangular waveguide horns

The radiation admittance and effective power transmission coefficient are derived by a field matching method for arbitrary scan of an infinite array of open rectangular waveguides. Higher order waveguide modes, as well as higher order modes in the free space cell above the array, are included in the field matching problem. The convergence of the solution was studied, and the number of external free space and internal waveguide modes necessary for an adequate answer are given. Numerical results are obtained and compared with previous theory and with experiment for rectangular grids. Comparison is also made with experiment on a triangular grid which exhibited an anomalous notch in the element pattern. The experimental results in both cases seem to substantiate the theory, at least to the extent that could be expected from the small test arrays that were used for the measurements. The comparison indicates that the method of analysis includes all of the necessary features required for the study of mutual coupling effects in infinite arrays of rectangular waveguides having thick walls.
Discrete approximations to continuous curves

We consider the problem of approximating a continuous curve by a piecewise linear one whose segments are assumed to be connected by universal joints. Rather than taking a least-squares approach, we require that the endpoints of the line segments lie on the continuous curve. We show that under these assumptions a single rotational degree of freedom remains. An algorithm is derived to determine the set of angles characterizing the relative orientation of each consecutive pair of line segments as a function of this rotational degree of freedom. Two examples are given to illustrate the procedure. The motivating application for this work is the control of a snake-like robot using a set of gaits designed from shape primitives
Cellulose Synthesis in Higher Plants

AbstractCellulose microfibrils play essential roles in the organization of plant cell walls, thereby allowing a growth habit based on turgor. The fibrils are made by 30 nm diameter plasma membrane complexes composed of approximately 36 subunits representing at least three types of related CESA proteins. The complexes assemble in the Golgi, where they are inactive, and move to the plasma membrane, where they become activated. The complexes move through the plasma membrane during cellulose synthesis in directions that coincide with the orientation of microtubules. Recent, simultaneous, live-cell imaging of cellulose synthase and microtubules indicates that the microtubules exert a direct influence on the orientation of cellulose deposition. Genetic studies in Arabidopsis have identified a number of genes that contribute to the overall process of cellulose synthesis, but the role of these proteins is not yet known.
Visual detection of bacterial pathogens via PNA-based padlock probe assembly and isothermal amplification of DNAzymes

We have developed a self-reporting isothermal system for visual bacterial pathogen detection with single base resolution. The new DNA diagnostic is based on combination of peptide nucleic acid (PNA) technology, rolling circle amplification (RCA) and DNAzymes. PNAs are used as exceedingly selective chemical tools that bind genomic DNA at a predetermined sequence under nondenaturing conditions. After assembly of the PNA-DNA construct a padlock probe is circularized on the free strand. The probe incorporates a G-quadruplex structure flanked by nicking enzyme recognition sites. The assembled circle serves as a template for a novel hybrid RCA strategy that allows for exponential amplification and production of short single-stranded DNA pieces. These DNA fragments fold into G-quadruplex structures and when complexed with hemin become functional DNAzymes. The catalytic activity of each DNAzyme unit leads to colorimetric detection and provides the second amplification step. The combination of PNA, RCA, and DNAzymes allows for sequence-specific and highly sensitive detection of bacteria with a colorimetric output observed with the naked eye. Herein, we apply this method for the discrimination of Escherichia coli, Salmonella typhimurium, and Clostridium difficile genomes.
VSP normal moveout stretch

The vertical seismic profiling, common depth‐point (VSPCDP) transformation is a technique used to image the reflected waves in an offset VSP. This coordinate transformation procedure maps reflection amplitudes from receiver depth and reflection times to lateral offset and reflector depth (Wyatt and Wyatt, 1981). The process involves the application of moveout correction followed by stacking. This moveout correction results in a distortion of the original waveform and a smear of the reflection event that consequently degrades the lateral resolution of the transformation (Owusu, 1991). Therefore, to determine the optimum processing parameters for the transformation we need to understand the effects of the VSP moveout stretch.
Impaired Cerebellar and Limbic Responses to the Valsalva Maneuver in Heart Failure

Heart failure (HF) patients show an inability to regulate autonomic functions, a characteristic which is associated with increased mortality. These autonomic deficits may stem from earlier demonstrated injury to central autonomic regulatory areas, providing a structural basis for the autonomic abnormalities. However, knowledge of structural injury provides insufficient insights into timing and magnitude of signal patterns within affected areas which lead to impaired autonomic outflow. Among damaged brain areas, cerebellar sites are key for timely coordination of sympathetic and parasympathetic attributes, and for dampening extremes of hypotension and hypertension induced by other injured sites, including hypothalamic and limbic areas. We collected functional magnetic resonance imaging (fMRI) signals in cerebellar and limbic areas to characterize amplitude and timing patterns of neural responses to the Valsalva maneuver, an autonomic challenge that elicits sequential sympathetic and parasympathetic responses, in 16 HF patients and 33 control subjects. HF patients showed distorted fMRI signal patterns during the challenge period in the cerebellar vermis, left cerebellar crus II, and left insula, whereas the right crus II and insula, and bilateral amygdalae showed normal patterns. However, all structures, except the left crus II, showed altered responses in HF during the recovery period. Crus II patterns reflected a failure of HF subjects to demonstrate the normal lateralized responses, while in the insula, HF subjects exhibited abnormal left-right patterns, relative to controls. The abnormal timing and response patterns in these injured areas critical for autonomic regulation likely contribute to the enhanced sympathetic outflow and autonomic dysfunction characteristic of HF.
Functional Interactions between Starch Synthase III and Isoamylase-Type Starch-Debranching Enzyme in Maize Endosperm

This study characterized genetic interactions between the maize (Zea mays) genes dull1 (du1), encoding starch synthase III (SSIII), and isa2, encoding a noncatalytic subunit of heteromeric isoamylase-type starch-debranching enzyme (ISA1/ISA2 heteromer). Mutants lacking ISA2 still possess the ISA1 homomeric enzyme. Eight du1- mutations were characterized, and structural changes in amylopectin resulting from each were measured. In every instance, the same complex pattern of alterations in discontinuous spans of chain lengths was observed, which cannot be explained solely by a discrete range of substrates preferred by SSIII. Homozygous double mutants were constructed containing the null mutation isa2-339 and either du1-Ref, encoding a truncated SSIII protein lacking the catalytic domain, or the null allele du1-R4059. In contrast to the single mutant parents, double mutant endosperms affected in both SSIII and ISA2 were starch deficient and accumulated phytoglycogen. This phenotype was previously observed only in maize sugary1 mutants impaired for the catalytic subunit ISA1. ISA1 homomeric enzyme complexes assembled in both double mutants and were enzymatically active in vitro. Thus, SSIII is required for normal starch crystallization and the prevention of phytoglycogen accumulation when the only isoamylase-type debranching activity present is ISA1 homomer, but not in the wild-type condition, when both ISA1 homomer and ISA1/ISA2 heteromer are present. Previous genetic and biochemical analyses showed that SSIII also is required for normal glucan accumulation when the only isoamylase-type debranching enzyme activity present is ISA1/ISA heteromer. These data indicate that isoamylase-type debranching enzyme and SSIII work in a coordinated fashion to repress phytoglycogen accumulation.
Crimes and Misdemeanors: A Review of Recent Research on Suicides in Prison.

By contrast with the attention that jail suicide has received in the last decade, suicide among longer-term prisoners has occasioned little public concern and less scholarly interest. This article reviews recent empirical studies of prison suicides, whose results call into question the conventional belief that longer-term prisoners rarely kill themselves. These studies suggest that completed suicide in prison is a serious public health problem, and that for certain sub-groups, the risks of completed suicide approach, and perhaps exceed those of jail detainees. Recent research bears out the connection between outward-turned aggression and suicide, and raises doubts about conventional conceptions of the anti-social personality. The implications for future suicide rates of the “graying” of the prison population, and of the AIDS epidemic within prisons are discussed, as are the needs for future research.