cssi/SciSciGPT-SciSciNet huggingface dataset:
Prevalent Vertebral Fractures in Black Women and White Women

Vertebral fractures are the most common osteoporotic fracture. Hip and clinical fractures are less common in black women, but there is little information on vertebral fractures. We studied 7860 white and 472 black women ≥65 yr of age enrolled in the Study of Osteoporotic Fractures. Prevalent vertebral fractures were identified from lateral spine radiographs using vertebral morphometry and defined if any vertebral height ratio was >3 SD below race-specific means for each vertebral level. Information on risk factors was obtained by questionnaire or examination. Lumbar spine, total hip, and femoral neck BMD and BMC were measured by DXA. The prevalence of vertebral fractures was 10.6% in black and 19.1% in white women. In age-adjusted logistic regression models, a 1 SD decrease in femoral neck BMD was associated with 47% increased odds of fracture in black women (OR = 1.47; 95% CI, 1.12–1.94) and 80% increased odds in white women (OR = 1.80; 95% CI, 1.68–1.94; interaction p = 0.14). The overall lower odds of fracture among black women compared with white women was independent of femoral neck BMD and other risk factors (OR = 0.51; 95% CI, 0.37–0.72). However, the prevalence of vertebral fractures increased with increasing number of risk factors in both groups. The prevalence of vertebral fractures is lower in black compared with white women but increases with age, low BMD, and number of risk factors.
A subset of chicken statoacoustic ganglion neurites are repelled by Slit1 and Slit2.

Abstract Mechanosensory hair cells in the chicken inner ear are innervated by bipolar afferent neurons of the statoacoustic ganglion (SAG). During development, individual SAG neurons project their peripheral process to only one of eight distinct sensory organs. These neuronal subtypes may respond differently to guidance cues as they explore the periphery in search of their target. Previous gene expression data suggested that Slit repellants might channel SAG neurites into the sensory primordia, based on the presence of robo transcripts in the neurons and the confinement of slit transcripts to the flanks of the prosensory domains. This led to the prediction that excess Slit proteins would impede the outgrowth of SAG neurites. As predicted, axonal projections to the primordium of the anterior crista were reduced 2–3 days after electroporation of either slit1 or slit2 expression plasmids into the anterior pole of the otocyst on embryonic day 3 (E3). The posterior crista afferents, which normally grow through and adjacent to slit expression domains as they are navigating towards the posterior pole of the otocyst, did not show Slit responsiveness when similarly challenged by ectopic delivery of slit to their targets. The sensitivity to ectopic Slits shown by the anterior crista afferents was more the exception than the rule: responsiveness to Slits was not observed when the entire E4 SAG was challenged with Slits for 40 h in vitro. The corona of neurites emanating from SAG explants was unaffected by the presence of purified human Slit1 and Slit2 in the culture medium. Reduced axon outgrowth from E8 olfactory bulbs cultured under similar conditions for 24 h confirmed bioactivity of purified human Slits on chicken neurons. In summary, differential sensitivity to Slit repellents may influence the directional outgrowth of otic axons toward either the anterior or posterior otocyst.
Effect of protease inhibitors on androgen receptor analysis in rat prostate cytosol

Abstract Prostate androgen receptors are liable to proteolytic digestion during in vitro analysis; thus, various proteolytic enzyme Inhibitors were tested for their ability to improve the androgen receptor assay. The serine (phenylmethylsulfonylflourlde, aprotinin, p-aminobenzamidine) and thiol-serine (leupeptin, bacitracin) protease inhibitors individually present in the homogenization buffer significantly increased the measurable androgen binding sites by 30–35% in rat prostate cytosol as determined by saturation analysis with [ 3 H]-l7β-hydroxy-l7-methyl- 4,9 11-estratrien-3-one (R-1881) for 20 hr at 4°C. The apparent binding affinity was also increased by these compounds. Various combinations were tried and aprotinin/bacitracin was found to be additive in effect. This combination was also shown to prevent receptor degradation as determined by sucrose density gradient centrifugation. The carboxyl protease inhibitor, pepstatin A, was ineffective in improving the receptor assay. Rabbit bile, an inhibitor of seminin, interfered with receptor binding thus rendering it ineffective for use in saturation analysis. The results show that the use of serine-thiol protease inhibitors significantly improves the cytosol androgen receptor yield and assay sensitivity; therefore, we recommend routine inclusion of these compound(s) in the homogenization buffer for androgen receptor assays.
Experimentally Observed Dynamical Characteristics of Mutually Coupled Semiconductor Lasers With or Without Optoelectronic Feedback

Mutually-coupled semiconductor lasers are of great current interest because of the important insight they provide into coupled physical, chemical, and biological systems. Two semiconductor lasers either with or without optoelectronic feedback are mutually coupled together through optoelectronic paths. It is found that mutual coupling can significantly affect the dynamics of the semiconductor lasers, depending on the coupling delay time and the coupling strength. Interesting phenomena such as generation of chaos, quasiperiodic and period-doubling bifurcation to chaos, and death by delay are observed. Synchronization of the chaotic outputs from mutually coupled semiconductor lasers is also observed.
One-dimensional exciton fusion kinetics in dilute polymer blends

Exciton-exciton and exciton-excimer triplet fusion kinetics is monitored in medium molecular weight P1VN/PMMA films with concentrations from 0.005 to 100% (weight), at temperatures of 77 to 300 K, via time-resolved fluorescence and phosphorescence (10 ns to 10 s). The triplet-triplet annihilation is bimolecular at short times but pseudo-monomolecular at long times. Furthermore, the heterogeneity exponent (h) is 0.5 for isolated P1VN chains, zero (classical) for pure P1VN and “fractal-like” (0<h<0.5) throughout certain concentration regimes. However, h is not monotomic with blend concentration but rather oscillates between zero and 0.5. Correlation is made with morphology changes (phase separation, filamentation). The long-lived decays do fit stretched exponentials, with a parameter β=1-h. Distinction is also made between diffusion- limited and reaction-limited kinetic regimes. Furthermore, the blend topology is also studied with the aid of the time-modulation technique, in which the time decays are obtained for different excitation durations, i.e., single pulse vs. cw or multiple-pulse laser excitation, but with equal global exciton densities at the start (t=0) of the decays. As expected, the triplet exciton kinetics is dominated by short-range hops (about 5 A) and thus monitors the primary topology of the chains. At concentrations below 0.01%, the excitons are constrained to a truly one-dimensional topology. This is probably the most ideal case of a molecular wire conducting elementary excitations.
Breast carcinoma metastatic to bladder

Breast carcinoma metastatic to the bladder and presenting initially with urinary tract symptoms has been reported only sporadically. Two cases, one unique in that the bladder was the sole site of metastasis, are reported herein, along with a review of the literature.
Controversy within a cooperative or competitive context and cognitive perspective-taking

Abstract Forty-five undergraduates discussed a moral issue with a confederate who had the same opinion (no controversy) or opposite opinion (controversy). Subjects in the controversy conditions discussed within either a cooperative or a competitive context. Subjects in the controversy conditions indicated more conceptual conflict or uncertainty, engaged in more information seeking behavior, and were more accurate in taking the cognitive perspective of the confederate than were subjects in the no-controversy condition. These results support Piaget's and Kohlberg's views of the role of controversy in perspective-taking and cognitive development and Berlyne's theory of conceptual conflict and epistemic curiosity. Subjects in the competitive-context conditions experienced more uncertainty, engaged in more information-seeking behavior, and were more accurate in cognitive perspective-taking than were subjects in the cooperative-context condition. Subjects in the competitive-context condition also experienced more cognitive dissonance, derogated the confederate and the confederate's position and arguments to a greater extent, and indicated greater closed-mindedness in responding to the confederate and the confederate's arguments than did subjects in the cooperative-context or the no-controversy conditions.
Serial abuse in children who are shaken.

• Serious injury can occur to children who are shaken, especially if the shaking is repeated or part of a pattern of abuse. Serial abuse in connection with children who are shaken and their siblings has important therapeutic and legal ramifications. From an ongoing study of child abuse and head trauma, 12 of 24 victims of shaking that resulted in intracranial injury were identified who had coexisting evidence of direct external trauma. Seventeen children (71%) had evidence of prior abuse, neglect, or both, including 8 who had multiple intracranial hemorrhages. Of the 21 families represented, 9 had more than one child, 3(3%) of which had several siblings who had been victims of child abuse. Shaking of children usually is not an isolated event, as it frequently has been preceded by other types of abuse. ( AJDC . 1990;144:58-60)
Vanadium Complexes in a Lewis Basic Room-Temperature 1-Ethyl-3-methyl-1H-imidazolium Chloride/Aluminum Chloride Molten Salt

Complexes of VCl3 and VCl4 have been formed in a Lewis basic room-temperature molten salt consisting of 1-ethyl-3-methyl-1H-imidazolium chloride and aluminum chloride. Electrochemical and spectroscopic studies show that 3 equiv of chloride can be added to VCl3 to form higher order chloride complexes. Each vanadium(III) complex can be reversibly oxidized to a corresponding vanadium(IV) complex. The potentials for the couples VCl4- ↔ VCl4 + e-, VCl52- ↔ VCl5- + e-, and VCl63- ↔ VCl62- + e- occur at 1.33, 1.23, and 1.00 V, respectively, measured versus a reference electrode consisting of an aluminum wire in a 0.6 mole fraction AlCl3 melt. Although higher order chloride complexes of other transition metals have been reported in these melts, this is the first metal for which the stepwise addition of chloride accompanied by reversible electrochemistry for each species has been demonstrated. This also shows that molten salts are useful for stabilizing complexes which may be hydrolyzed by the residual water somet...
Planets: The first movement

How do large objects form from the dusty gas surrounding a young star? A simulation suggests that several familiar processes, among them gas turbulence and self-gravitation, might work together to get the job done.
Effect of silicon on antioxidant and stomatal response of two grapevine (Vitis vinifera L.) rootstocks grown in boron toxic, saline and boron toxic-saline soil

Abstract We investigated individual and combined effects of B toxicity and salinity in the presence or absence of silicon on the shoot growth, concentrations of sodium (Na), chloride (Cl), boron (B) and silicon (Si), and stomatal resistance (SR), lipid peroxidation (MDA), proline accumulation, H2O2 accumulation and the activities of major antioxidant enzymes (superoxide dismutase, SOD; catalase, CAT and ascorbate peroxidase, APX) activity grapevine rootstocks of 41B (V. Vinifera × V. Berlandieri) and 1103P (V. Berlandieri × V. Rupestris). Applied Si counteracted the deleterious effects of salinity and boron toxicity on shoot growth by lowering the accumulation of Na in 1103P, and B and Cl in the both rootstocks. Stomatal resistance, MDA, and the concentrations of H2O2 and proline were higher in the plants grown in conditions of B toxicity, salinity and their combination while applied Si lowered these parameters. Lowering SOD and CAT but increasing APX, Si treatment significantly affected the enzyme activities of both rootstocks. Based on the present work, it can be concluded that Si alleviates the adverse effects of salinity, B toxicity and combined salinity-B toxicity on grapevine rootstocks by preventing both oxidative membrane damage and translocation of Na and B from root to shoots and/or soil to plant, and also lowering the phytotoxic effects of Na and B within plant tissues. When considering the antioxidative response and membrane systems, it was concluded that the rootstock 1103P was responsive to Si under stress conditions. To our knowledge, this is the first report that Si improves the combined salt and B tolerance of grapevine grown under saline, B toxic, and B toxic and saline conditions which describes membrane related parameters and antioxidant responses.
Relation between structure and gas transport properties of polyethylene oxide networks based on crosslinked bisphenol A ethoxylate diacrylate

Abstract Poly(ethylene oxide) (PEO) networks prepared from the photopolymerization of bisphenol A ethoxylate diacrylate (BPA–EDA) have been investigated as a function of crosslinker molecular weight and copolymer composition. Dynamic mechanical and dielectric methods have been used to elucidate the thermal relaxation characteristics of the polymers as a function of network composition and architecture, and these properties were related to measured gas transport for CO 2 separations. Copolymerization strategies involving the insertion of flexible PEG side chains along the network backbone proved effective in enhancing network free volume and increasing permeability. The gas transport performance of rubbery amorphous membranes based on the n =15 BPA–EDA crosslinker (i.e., crosslinker encompassing 30 ethylene oxide repeat units between crosslinks) compared favorably to model polymers synthesized from poly(ethylene glycol) diacrylate.
Channel shape optimization of solid oxide fuel cells using advanced numerical techniques

Shape optimization of fuel channels in solid oxide fuel cells (SOFC) is presented. A three-dimensional, implicit, multi-species fuel cell solver is developed to compute the baseline solution. Sensitivity derivatives required for the optimization are computed using the discrete adjoint method. A gradient-based optimizer is utilized to update the design variables. The geometry of the fuel channel is parameterized to obtain meaningful design variables using a recently developed technique that is applicable for multi-disciplinary design optimization. During the design process, the mesh is continually modified to reflect the changes in the underlying geometry. An automated environment to sequentially execute the aforementioned processes is developed. Cost functions representating the cell voltage and uniform distribution of fuel among all channels are optimized with respect to the shape of the fuel channels.
MECHANISM OF RNA POLYMERASE ACTION: CHARACTERIZATION OF THE DNA-DEPENDENT SYNTHESIS OF POLYADENYLIC ACID.

Purified preparations of DNA-dependent RNA polymerase from Escherichia coli catalyse a DNA-dependent synthesis of long-chain polyadenylic acid when ATP is the only ribonucleoside triphosphate added to the reaction. Polyadenylic acid synthesis differs from DNA-dependent synthesis of complementary RNA in three important respects. First, the chain-length of the polyadenylic acid product is greater by 5 to 10 times than that of the deoxythymidylic acid sequence in DNA which serves as template. Secondly, addition of one, two or all three of the other ribonucleoside triphosphates to the reaction at low concentrations (less than 2×10 −6 M ) brings about a striking inhibition of polyadenylic acid synthesis. In the presence of all four of the ribonucleoside triphosphates, no polyadenylic acid is produced. Inhibition by any given ribonucleoside triphosphate is dependent on the presence in the DNA template of the nucleotide base complementary to that inhibiting triphosphate. Finally, only single-stranded DNA serves to direct polyadenylic acid synthesis. It is proposed that DNA-dependent polyadenylic acid synthesis is due to a reiterative copying of short sequences of thymidylic acid residues in the DNA template rather than to a separate polyadenylic acid polymerase. The inhibition of this synthesis by the other ribonucleoside triphosphates may be due to fixation of the enzyme on the template at a deoxynucleotide base complementary to the base of the inhibiting triphosphate, thus preventing further copying of thymidylic acid sequences. The relevance of these findings to the general mechanism of polynucleotide synthesis by this enzyme is discussed.
GEOGRAPHIC VARIATION IN HOST SPECIFICITY REVEALS HOST RANGE EVOLUTION IN UROLEUCON AMBROSIAE APHIDS

Some herbivorous insect taxa that exhibit otherwise conservative patterns of host association include species or populations with atypical host specificities. These species provide special opportunities to study the evolution of host range. Uroleucon ambrosiae aphids present an example. Most Uroleucon species are monophagous on particular host plants from the Asteraceae, and U. ambrosiae appears to specialize on the giant ragweed, Ambrosia trifida, in eastern North America. In the American Southwest, however, U. ambrosiae uses a variety of asteraceous taxa as hosts. For the present study, we assayed host-associated behaviors of U. ambrosiae from both eastern and southwestern regions of the United States on each of four asteraceous genera. Data from choice and no-choice experiments and electrical penetration graph analyses revealed highly significant differences in the acceptability of the four test plants. Plant taxa were ranked in the same order across multiple behavioral assays by aphids from both regions. However, eastern and southwestern aphids exhibited significantly different patterns of behavior. Ambrosia was the most highly accepted plant by aphids from both regions, but southwestern aphids accepted the other test plants more readily than did eastern aphids, indicating geographic variation in degree of host specificity. This regional differentiation held for aphids reared under controlled conditions for the EPG studies, indicating a genetic basis for population divergence in U. ambrosiae host-use traits. We speculate that the generalism within U. ambrosiae is an evolutionarily derived trait and represents an ecological adaptation to the scattered and unpredictable distribution of the preferred A. trifida host in the arid American Southwest.
Sentence processing in Chinese-American bilinguals

Abstract This study compares metalinguistic ratings for English words done by Chinese-English bilinguals and monolingual English speakers. Bilinguals generally rated English words as contributing more to both the meaning and structure of their sentences than did monolinguals. Further, on a relative basis, bilinguals rated English content words as contributing more to structure and function words as contributing more to meaning than monolinguals. Language-specific differences are shown to be consistent with these differences in the cognitive processing of linguistic information. These processing differences suggest ways in which the bilingual's languages interact during sentence processing.
Effect of feed consumption on plasma amino acid concentrations in lambs.

Abstract Increased consumption of a corn-soybean meal diet from maintenance through increments to approximately 2.5 times maintenance increased weight gain, gain :feed, plasma urea-nitrogen, and concentrations of most plasma free-amino acids. The failure of plasma sulfur-containing amino acids and histidine to increase with increased diet consumption may indicate that these amino acids were limiting performance. Since it influences plasma amino acid concentrations, feed intake is a major factor in interpretation of plasma amino acid data.
Determination of Volatile Organic Compounds (VOCs) in Potable Water Using Solid Phase Micro Extraction-Gas Chromatography (SPME-GC)

This study is aimed at detection and estimation of five Volatile Organic Compounds (carbon tetrachloride, tetrachloroethylene, 1,2-dichloroethane, 1,1,1-trichloroethane and 1,2,3-trichlorobenzene) by gas chromatography (GC). These compounds pose a risk to human health as well as environment. As the conventional sample extraction methods are laborious and tiresome involving frequent handling with solvents; solid phase micro extraction (SPME) technique was employed which is robust and cost-effective method of sample extraction with minimal exposure and handling of solvents. Sample extraction time was optimized as a first step by executing replicate analysis over 1, 5, 10 and 15 min while keeping certain other parameters constant; electron capture detector (ECD) was employed for the detection of analytes. As a second step, reproducibility of SPME fiber was verified by running replica; relative standard deviation was ranging from 3.5 to 19.3 %. Drinking water samples collected from selected gas and petrol stations were then analyzed as an application of the SPME-GC-ECD method. A total of 5 out of 27 sites were found to be contaminated with the compounds of concern mentioned above; two of them (1,2-dichloroethane, 1,1,1-trichlorobenzene) showed contamination above US-EPA’s prescribed limits.
Intraventricular NGF infusion in the mature rat brain enhances sympathetic innervation of cerebrovascular targets but fails to elicit sympathetic ingrowth

Abstract The ability of peripheral axons to regenerate long distances in the peripheral nervous system (PNS) is well documented; however, examples of axonal elongation within the adult mammalian central nervous system (CNS) are rare. One example of axonal growth in the mature brain is the sprouting of sympathetic axons into the hippocampal formation following disruption of the septohippocampal pathway. A current hypothesis is that elevated hippocampal NGF levels, secondary to loss of retrograde transport by septal neurons, elicits sympathetic ingrowth. In this study, we sought to determine whether elevation of hippocampal NGF activity without septal denervation is sufficient to elicit sympathetic sprouting. Forty-one female rats were infused for two weeks with NGF or cytochrome C in the right lateral ventricle through cannulae connected to an osmotic minipump. In some animals the brains were sectioned and stained for acetylcholinesterase (AChE) activity and norepinephrine histofluorescence; in others, CNS tissue was assayed for nerve growth factor (NGF) content with a two-site ELISA. A Farrand microspectrophotometer was used to measure the intensity of catecholamine fluorescence around the internal carotid artery. The average fluorescence intensity of the sympathetic innervation of the internal carotid artery in the NGF-injected animals was over twice that of vehicle-injected rats indicating that the infused NGF was both accessible to the sympathetic axons and biologically active. However, in none of the cases with elevated hippocampal NGF levels were sympathetic axons observed within the hippocampal formation or any other brain region. These results suggest that simple elevation of brain NGF, while perhaps necessary, is insufficient to permit the growth of sympathetic axons into the mature mammalian CNS.
A parameter adjustable regulator for a winding process

A parameter imbedding method for simplified near-optimum design of a class of nonlinear systems is presented. It is applied to the design of a tension regulator system for a strip winding process. The feedback controller is continuously adjusted to follow a slowly varying process variable. Results of a simulation test for a particular steel-strip rolling mill are included.
Posturally induced transitions in rhythmic multijoint limb movements.

The coordination dynamics (e.g., stability, loss of stability, switching) of multijoint arm movements are studied as a function of forearm rotation. Rhythmical coordination of flexion and extension of the right elbow and wrist was examined under the following conditions: (1) forearm supine (forearm angle 0°), simultaneous coordination of wrist flexion/elbow flexion and wrist extension/elbow extension (termed in-phase); and (2) forearm prone (forearm angle 160°), simultaneous coordination of wrist flexion/elbow extension and wrist extension/elbow flexion (termed anti-phase). Starting in either pattern, subjects rotated the forearm in nine 20° steps, producing 15 cycles of motion per step at a frequency of 1.25 Hz. Spontaneous transitions from pattern 1 to pattern 2 and from pattern 2 to pattern 1 were observed at a critical forearm angle. The critical angle depended on the direction of forearm rotational change, thus revealing the hysteretic nature of the switching process. En route to the transition, regardless of direction of forearm rotation, enhancement of phase fluctuations and an increase in perturbation response times (critical slowing down) were observed in the relative phasing between the joints. Such observations support loss of stability as a central, self-organizing process underlying coordinative change. Neurophysiological mechanisms supporting multijoint coordinative dynamics are discussed.
Homological methods in algebraic map theory

The primary intent of the present paper is to adapt familiar notions of algebraic topology, such as the fundamental group, homology, and cohomology to the context of algebraic maps and their (ramified) covering projections. The notion of a principal derived map is already fairly well understood in terms of the defining voltages; however, once it is recognized that voltages are essentially cohomological in nature, the functorial interplay among homology provides a very tractible methodology for studying such properties as connectivity or regularity of the covering, or for obtaining explicit constructions of the voltages affording the given covering map.
Optical effects of energetic copper-ion irradiation on copper mirrors

The optical effects of radiation damage to metal mirrors have been examined using copper-ion beams incident on copper mirrors. Incident ion energies of 2, 5, and 8 MeV were used and dose levels were examined up to 4 × 1016 ions/cm2. Both crystalline and OFHC copper mirrors were studied. In situ ellipsometric data were recorded (λ = 633 nm) during the irradiations to determine the dose-dependent behavior of the radiation effects. Spectral reflectivity and optical scattering were evaluated for samples before and after the irradiations. Complementary analysis of the samples was performed with scanning electron microscopy, Auger electron spectroscopy, and electron spectroscopy for chemical analysis. Significant changes in ellipometric parameters were noted during the irradiations. After exposure to large dose values, the optical properties of crystalline mirrors were consistent with the optical properties of bare copper. The ellipsometric changes have been attributed to alteration of the surface oxide film. Dose-dependent data have been used to determine the important damage mechanisms.
Electroconductivity and viscosity of complexes of poly(vinylpyridines) with alkali metal salts in organic solvents

The complexation of poly(4-vinylpyridine) (1), poly(2-methyl-5-vinylpyridine) (2) and poly(2-vinylpyridine) (3) with bromides, perchlorates and tetraphenylborates of alkali metals in organic solvents was investigated by means of electroconductivity, viscometry and nuclear magnetic resonance spectroscopy. The influence of the nature of the polymer, the low-molecular-weight salt and the solvent, salt and polymer concentration as well as the temperature on complexation was studied. The fraction of cations and that of polymer units bound were determined. The compositions of the complexes were found by means of viscometry. It was established that the mechanism of binding of the polymers with alkali metal salts is of the ion-dipole type.
Purifying the Body Politic: Steroids, Rafael Palmeiro, and the Rhetorical Cleansing of Major League Baseball

When President George W. Bush used his 2004 State of the Union address to condemn the use of performance-enhancing drugs in professional sports, many reacted with confusion or frustration that a seemingly trivial matter was placed in context with the “war on terror” and a struggling economy. However, these reactions overlook the consistency between the rhetoric that seeks to ban steroids and the broader rhetoric about national community after 9/11. In this essay, I argue that the attempt to purify and inoculate the “body politic” against foreign threats is metaphorically replicated by the attempt to purify the bodies within the national pastime by banning performance-enhancing drugs. Using baseball as a metaphor for the nation, Bush's attention to steroids was later dramatized through the suspension of Rafael Palmeiro. Thus, through the subsequent scapegoating of Palmeiro, the community of sport reproduced the politics of fear and division that have characterized post-9/11 America.
The role of meaning in interpreting graphical and textual feedback during a computer-based simulation

Abstract The purpose of this study was to investigate the ability of adult learners to process and interpret graphical and textual feedback during a computer-based simulation when the feedback originated from contexts varying widely in meaning. A total of 41 subjects interacted with a computer simulation of the laws of motion using a discovery-based approach embedded within one of two contexts (meaningful and arbitrary). In the meaningful context the simulation was designed to be analogous to miniature golf, whereas the arbitrary context used no such organizer. Both simulation contexts provided alternating forms of graphical and textual feedback. Four dependent measures were used: Pretest/Posttest Performance, Game Score, Interactivity, and Frustration. Results indicated no significant main effects or interactions between the meaningful and arbitrary contexts on any of the dependent measures. However, subjects scores on the posttest were significantly higher than on the pretest indicating general effectiveness of the simulation as a discovery-based learning environment. There were also significant within-subject main effects found on the type of feedback provided. Subjects completed the game task in less time and were less frustrated when given animated graphical feedback than when given textual feedback. Subjects also interacted less (in terms of mouse clicks) when given graphical feedback. In addition to the quantitative analysis, a qualitative analysis was also conducted with 14 additional subjects. This analysis revealed interesting trends in how some subjects used the various feedback representations in the simulation to construct and test learning strategies versus those whose interaction generally remained shallow and reactionary.
Functional analysis of an archaebacterial voltage-dependent K+ channel.

All living organisms use ion channels to regulate the transport of ions across cellular membranes1. Certain ion channels are classed as voltage-dependent because they have a voltage-sensing structure that induces their pores to open in response to changes in the cell membrane voltage. Until recently, the voltage-dependent K+, Ca2+ and Na+ channels were regarded as a unique development of eukaryotic cells, adapted to accomplish specialized electrical signalling, as exemplified in neurons. Here we present the functional characterization of a voltage-dependent K+ (KV) channel from a hyperthermophilic archaebacterium from an oceanic thermal vent. This channel possesses all the functional attributes of classical neuronal KV channels. The conservation of function reflects structural conservation in the voltage sensor as revealed by specific, high-affinity interactions with tarantula venom toxins, which evolved to inhibit eukaryotic KV channels.
Community or Colony: the Case of Online Newspapers and the Web

Although the development of relationships on the Net may be seen as “community,” the increasing global presence from commercial media such as online newspapers suggest that another metaphor may be jousting for preeminence – colonization. Findings from an on-going case study of online newspapers suggest the early ideals of democratic community-building in cyberspace are encountering resistance as newspaper organizations delineate “virtual geographic space” and stake out “territory” on the web by subtly discouraging access to other sites (i.e., a type of virtual “homesteading”). Additionally, changes in the production practices of print journalists due to the emergence of electronic newspapers are discussed.
Molecular Chaperones: Panning for chaperone-binding peptides

Experiments designed to define the substrate-binding preferences of the molecular chaperone BiP show that bound peptides are characterized by a heptameric motif with alternating hydrophobic residues.
Doty, R. Getting Started as a Pharmacy Preceptor. Washington, D.C. American Pharmacists Association; 2011, 153pp, $31.50 (paperback), ISBN 9781582121468.

Getting Started as a Pharmacy Preceptor is a book with 9 short chapters and case studies for preceptors to learn how to become and be a better preceptor. It is a great book to use for new and existing preceptors. It has useful tips and reiterates good practice for preceptors. Each chapter is divided by topics, so it is easy to find a specific area on which you need ideas and suggestions. Chapter 1 titled “Are You Precepting for the Right Reasons” gives 2 lists, one filled with right reasons and the other list with wrong reasons. The chapter goes on to explain the lists and how preceptors can broaden their impact on students. Chapter 2 helps preceptors determine what type of rotation IPPE and/or APPE to offer and the appropriate number of students to have at the site. Chapter 3, titled “Getting Ready,” provides information on the steps on how to become a preceptor. The steps include who to contact, what questions to ask, how to develop a syllabus, and useful tips on activities and evaluations. Chapter 4 gives suggestions for precepting your first student and how to receive feedback for improvement for future students. Chapter 5 explains the importance of integrating students into the site and gives suggestions on how to create valuable experiences for the students. Chapter 6 and 7 discuss the importance of giving and receiving feedback and how to use feedback for continuous improvement. The chapters remind preceptors to document regularly and thoroughly and to solicit feedback from students and peer reviews to use for improvement. Chapter 8 encourages preceptors to become artists and to be creative with the design of the experiences they have to offer students. Chapter 9 provides ideas on how to overcome student problems and to potentially avoid unintended consequences. A helpful table of descriptions of today’s generations is also provided in this chapter. There are 8 cases at the end of the book with a specific problem. Each case begins with a cartoon that preceptors can relate to and adds humor to the read. Each case makes preceptors aware of situations that may occur and provides plans on how to a handle the problem. The conclusion provides final tips for the reader. Overall, this book provides high-quality content in a simple, readable format. Preceptors can use the book as a resource on ways to become a preceptor, how to design and improve their rotation, and ideas for handling student issues. The book could be given to new graduates to encourage them to give back to their profession by becoming a preceptor and to new preceptors to show appreciation for becoming a preceptor.
Increased extracellular pressure stimulates tumor proliferation by a mechanosensitive calcium channel and PKC-β

Abstract Large tumors exhibit high interstitial pressure heightened by growth against the constraining stroma. Such pressures could stimulate tumor proliferation via a mechanosensitive ion channel. We studied the effects of 0–80 mmHg increased extracellular pressure for 24 h on proliferation of SW620, Caco-2, and CT-26 colon; MCF-7 breast; and MLL and PC3 prostate cancer cells, and delineated its mechanism in SW620 cells with specific inhibitors and siRNA. Finally, we compared NF-kB, phospho-IkB and cyclin D1 immunoreactivity in the high pressure centers and low pressure peripheries of human tumors. Pressure-stimulated proliferation in all cells. Pressure-driven SW620 proliferation required calcium influx via the T-type Ca2+ channel Cav3.3, which stimulated PKC-β to invoke the IKK-IkB–NF–kB pathway to increase proliferation and S-phase fraction. The mitotic index and immunoreactivity of NF-kB, phospho-IkB, and cyclin D1 in the center of 28 large human colon, lung, and head and neck tumors exceeded that in tumor peripheries. Extracellular pressure increases [Ca2+]i via Cav3.3, driving a PKC-β- IKK- IkB–NF–kB pathway that stimulates cancer cell proliferation. Rapid proliferation in large stiff tumors may increase intratumoral pressure, activating this pathway to stimulate further proliferation in a feedback cycle that potentiates tumor growth. Targeting this pathway may inhibit proliferation in large unresectable tumors.
Molecular recognition of diketide substrates by a β-ketoacyl-acyl carrier protein synthase domain within a bimodular polyketide synthase

Abstract Background: Modular polyketide synthases (PKSs) are large multifunctional proteins that catalyze the biosynthesis of structurally complex bioactive products. The modular organization of PKSs has allowed the application of a combinatorial approach to the synthesis of novel polyketides via the manipulation of these biocatalysts at the genetic level. The inherent specificity of PKSs for their natural substrates, however, may place limits on the spectrum of molecular diversity that can be achieved in polyketide products. With the aim of further understanding PKS specificity, as a route to exploiting PKSs in combinatorial synthesis, we chose to examine the substrate specificity of a single intact domain within a bimodular PKS to investigate its capacity to utilize unnatural substrates. Results: We used a blocked mutant of a bimodular PKS in which formation of the triketide product could occur only via uptake and processing of a synthetic diketide intermediate. By introducing systematic changes in the native diketide structure, by means of the synthesis of unnatural diketide analogs, we have shown that the ketosynthase domain of module 2 (KS2 domain) in 6-deoxyerythronolide B synthase (DEBS) tolerates a broad range of variations in substrate structure, but it strongly discriminates against some others. Conclusions: Defining the boundaries of substrate recognition within PKS domains is crucial to the rationally engineered biosynthesis of novel polyketide products, many of which could be prepared only with great difficulty, if at all, by direct chemical synthesis or semi-synthesis. Our results suggest that the KS2 domain of DEBS1 has a relatively relaxed specificity that can be exploited for the design and synthesis of medicinally important polyketide products.
Time Scales in Atmospheric Chemistry: Coupled Perturbations to N2O, NOy, and O3

Nitrous oxide (N2O) is one of the top three greenhouse gases whose emissions may be brought under control through the Framework Convention on Climate Change. Current understanding of its global budget, including the balance of natural and anthropogenic sources, is largely based on the atmospheric losses calculated with chemical models. A representative one-dimensional model used here describes the photochemical coupling between N2O and stratospheric ozone (O3), which can easily be decomposed into its natural modes. The primary, longest lived mode describes most of the atmospheric perturbation due to anthropogenic N2O sources, and this pattern may be observable. The photolytic link between O3 and N2O is identified as the mechanism causing this mode to decay 10 to 15 percent more rapidly than the N2O mean atmospheric lifetime, affecting the inference of anthropogenic sources.
A suggestion for computing objective function in model calibration

Abstract A parameter-optimization process (model calibration) is usually required for numerical model applications, which involves the use of an objective function to determine the model cost (model-data errors). The sum of square errors (SSR) has been widely adopted as the objective function in various optimization procedures. However, ‘square error’ calculation was found to be more sensitive to extreme or high values. Thus, we proposed that the sum of absolute errors (SAR) may be a better option than SSR for model calibration. To test this hypothesis, we used two case studies—a hydrological model calibration and a biogeochemical model calibration—to investigate the behavior of a group of potential objective functions: SSR, SAR, sum of squared relative deviation (SSRD), and sum of absolute relative deviation (SARD). Mathematical evaluation of model performance demonstrates that ‘absolute error’ (SAR and SARD) are superior to ‘square error’ (SSR and SSRD) in calculating objective function for model calibration, and SAR behaved the best (with the least error and highest efficiency). This study suggests that SSR might be overly used in real applications, and SAR may be a reasonable choice in common optimization implementations without emphasizing either high or low values (e.g., modeling for supporting resources management).
Mutually transformative missions: A postcolonial, process-relational Pentecostal missiology

This article comprises a development of Amos Yong’s three-phase Pentecostal missiology in the direction of postcolonialism fostering “mutually transformative missions.” An appropriation of theologi...
Inter-species sexual discrimination and approach-avoidance conflict in two species of fiddler crabs, Uca pugnax and Uca pugilator

Factors responsible for inter-species sex recognition and conflict in Uca pugnax and Uca pugilator were investigated. Although both species responded appropriately to conspecific males and females, U. pugilator males responded to female-like counterspecifics stimuli with courtship display, while U. pugnax responded with agonistic display toward counterspecific females. Uca pugnax responded on 93·3 per cent of the trials with agonistic display toward the male-like counterspecific stimuli, while U. pugilator responded likewise only 66·7 per cent of the time. Inter-species stimuli elicited agonistic display 80 per cent of the time from U. pugnax, but approach-avoidance conflict from U. pugilator. Data interpretations included: (a) methods of mate selection; (b) visual discrimination; and (c) environmental and evolutionary differences.
Photocatalytic degradation of bacteriophages evidenced by atomic force microscopy.

Methods to supply fresh water are becoming increasingly critical as the world population continues to grow. Small-diameter hazardous microbes such as viruses (20–100 nm diameter) can be filtered by size exclusion, but in this approach the filters are fouled. Thus, in our research, we are investigating an approach in which filters will be reusable. When exposed to ultraviolet (UV) illumination, titanate materials photocatalytically evolve •OH and O2•− radicals, which attack biological materials. In the proposed approach, titanate nanosheets are deposited on a substrate. Viruses adsorb on these nanosheets and degrade when exposed to UV light. Using atomic force microscopy (AFM), we image adsorbed viruses and demonstrate that they are removed by UV illumination in the presence of the nanosheets, but not in their absence.
Pericarditis of acute myocardial infarction.

Forty patients with acute myocardial infarction and pericarditis (AMI-P) were encountered over a three-year period. The incidence of AMI-P was 7.2 percent (40 of 554 patients). Fifty consecutive patients with acute transmural infarction without pericarditis (AMI-C) were used as a control group. There were no significant differences between the AMI-P and AMI-C groups regarding age, sex, infarct location, hospital stay or mortality. Painful symptoms of pericarditis were experienced by 37 patients (92 percent), all of whom had developed symptoms by the fourth hospital day. The pericardial friction rub lasted three days or less in 34 patients (85 percent), but an occasional rub could be heard for up to eight days. Twenty patients with AMI-P (50 percent) developed pleural effusions and/or parenchymal pulmonary infiltrates. Twenty-eight AMI-P patients (70 percent) were thought to have had congestive heart failure (CHF) on the basis of their symptoms and physical findings. Radiographic examination could confirm only 13 cases of CHF among the 28 patients in whom the diagnosis was made clinically. Glucocorticoids were given parenterally to 31 of the 37 patients (84 percent) who had symptomatic pericarditis and was felt to be effective in ameliorating painful symptoms. Followup data was obtained on 28 of the 32 surviving patients. Five patients (15 percent) had seven episodes of the postmyocardial infarction syndrome (PMIS). Pericarditis is generally a shortlived complication of acute myocardial infarction. Pleural and parenchymal pulmonary abnormalities are common and probably account for the tendency to “overdiagnose” CHF in patients with AMI-P. PMIS appears to occur more frequently in patients who have had pericarditis at the time of the acute myocardial infarction.
Comparison of functional activation foci in children and adults using a common stereotactic space

The development of methods allowing direct comparisons between child and adult neuroimaging data is an important prerequisite for studying the neural bases of cognitive development. Several issues arise when attempting to make such direct comparisons, including the comparability of anatomical localization of functional responses and the magnitude and time course of the hemodynamic responses themselves. Previous results suggest that, after transformation into a common stereotactic space, anatomical differences between children (ages 7 and 8) and adults are small relative to the resolution of fMRI data. Here, we investigate whether time courses (BOLD responses) and locations of functional activation foci show similarities as well. Event-related fMRI was performed on 16 children (ages 7 and 8) and 16 adults, who pressed buttons in response to a visual stimulus. After transforming images into Talairach space, the coordinates of four consistent activations in each hemisphere were determined for each subject: two foci in the sensorimotor cortex, one focus in the visual cortex, and one focus in the supplementary motor area (eight activations in total). In seven foci, time courses were similar between children and adults, and peak amplitudes of time courses were comparable in all eight foci. There were negligible between-group differences in location of all foci. Variability of activation location was statistically similar in the two groups. In voxelwise group comparison images, minimal differences were found between children and adults in visual and motor cortex regions. The small differences in time courses and locations of activation foci between child and adult brains validate the feasibility of direct statistical comparison of these groups within a common space.
When Do Votes Count? Regime Type, Electoral Conduct, and Political Competition in Africa

The effects of electoral systems have been tested recently in Africa, raising several questions: Are the systematic effects of electoral rules the same across regime types? Does the conduct of elec...