cssi/SciSciGPT-SciSciNet huggingface dataset:
Effect of growth hormone on hepatic glucose and insulin metabolism after oral glucose in conscious dogs.

This study examined the effect of growth hormone (GH) on hepatic glucose metabolism and on the fractional extraction of insulin and glucagon after oral glucose administration. GH treatment [canine GH (0.75 mg/day for 7 days)] significantly increased basal portal vein and hepatic artery flow (P < 0.01 compared with pre-GH treatment). After GH treatment and after oral glucose, glucose levels significantly exceeded those before GH at 100 and 120 min in arterial and portal vein plasma and 120 min in the hepatic vein. The net hepatic uptake of glucose was similar before and after GH treatment. The increment of net nonhepatic splanchnic insulin balance above basal was 131 +/- 31 mU.kg-1.3 h-1 before and 272 +/- 46 mU.kg-1.3 h-1 after GH treatment (P < 0.05). An increase in fractional hepatic extraction of insulin occurred before GH treatment and was significantly greater at 60 min. In summary, despite the increased insulin content after GH administration, there was no change in hepatic uptake of glucose, indicating that the liver was also the site of insulin resistance.
Phytoplankton modeling involving random rate constants (part ii): Stochastic formulation†

The stochastic analysis of a model for phytoplankton production in a marine ecosystem is developed as an extension of the deterministic model presented previously in part IJ| A system of linear differential equations modeling the flow of nutrient through three components of an ecoiogical system is considered as if the parameters governing this nutrient flow are not fixed constants but are considered as random variables with specified probability distributions. The theory necessary to view the model in this more realistic stochastic setting is presented. Mean, variance, and correlation behavior of the solution process are investigated under various probabilistic structures for the parameters. Examination of these statistical aspects of the solution yields new insights into the predation dynamics and parameter relationships of the model.
Attachment cognitions and college and work functioning two years later in late adolescent women

This longitudinal study of 134 female high school seniors investigated the relationship between attachment cognitions and school and work functioning two years later. School functioning was indexed by interviewer-rated strain, stressful events, academic performance, and self-reported attitudes toward college. Work functioning was indexed by interviewer-rated strain, stressful events, and self-reported attitudes toward work. Attachment cognitions were found to be correlated with school strain, number and stress of school-related events as well as self-reported satisfaction, stress, and problems meeting deadlines. Attachment cognitions were found to be correlated with work strain, work satisfaction, tendency to overcommit, and performance anxiety. Most of these relationships persisted even when initial symptomatology was accounted for. These findings lend support to the hypothesis, derived from attachment theory, that secure attachment cognitions provide a secure base that allows the late adolescent to negotiate the challenges of college and work successfully.
Quality Assurance in Health Education

Abstract The mechanisms by which the profession of health education is seeking to promote increased competency, visibility, marketability, and quality among practitioners include professional preparation with a health education emphasis, certification by examination, and recertification with a specified number of continuing education contact hours. These requirements are not without critics and concerns. A discussion about examination construction and the benefits of continuing education are provided to help clarify some of the key concepts in the health education credentialing movement.
Infants of drug addicts: At risk for child abuse, neglect, and placement in foster care

In a methadone maintenance program for pregnant, drug dependent women, an investigation was undertaken (1) to study the occurrence of violence experienced by the women as children and as adults and (2) to lean whether those who report past violence/abuse are more likely to neglect and/or abandon their children to the care of others. Subjects included 178 drug dependent women who completed a Violence Questionnaire and 70 comparable, but drug-free women. Results revealed that a history of violence or abuse is related to drug abuse and also to the placement of one's child(ren) in foster care.
Synthesis of thermotropic LCPs using p-methoxycarbonyloxy aromatic acids

4-Methoxycarbonyloxybenzoic acid (MCOBA) and 6-methoxycarbonyloxy-2-naphthoic acid (MCONA) were synthesized as new monomers to replace 4-acetoxybenzoic acid (ABA) and 6-acetoxy-2-naphthoic acid (ANA) in the synthesis of liquid crystal polymers. MCOBA and MCONA (73 : 27, mol : mol) were reacted at temperatures ranging from 220 to 325°C in bulk. The copolymer (Mw = 14,200) has a Tg (90°C) and a Tm (249°C). The MCOBA/MCONA copolymer is lighter in color than the ABA/ANA copolymer. During the copolymerization, six by-products were collected, isolated, and analyzed, and their formation was investigated. The copolymerization rate was studied by the measurement of evolved carbon dioxide. The polymerization of MCOBA and MCONA is cleaner and faster than the polymerization of ABA and ANA. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 1703–1707, 1999
Effects of serotonin agonists on lordosis, myoclonus, and cytoplasmic progestin receptors in guinea pigs.

Abstract Peripheral treatment with the serotonin releaser fenfluramine or the serotonin agonist quipazine abolished lordosis behavior in ovariectomized estradiol and progesterone-primed female guinea pigs. Quipazine was also effective when administered into a lateral cerebroventricle. The lowest dose of fenfluramine that induced myoclonus (10 mg/kg) was higher than the dose needed to inhibit lordosis (5 mg/kg). Therefore, it appears that myoclonus and lordosis are differentially sensitive to serotonin agonists. The effects of quipazine on lordosis were time dependent. Quipazine had no effect on lordosis when given prior to the onset of sexual receptivity. These data suggest that serotonin agonists might be effective only when progesterone has had sufficient time to induce sexual receptivity. Quipazine did not affect cytoplasmic progestin receptors in brain areas involved in steroid hormone effects on lordosis. This finding, and the finding that quipazine had no effect on lordosis when given prior to the onset of sexual receptivity, suggest increased serotonin transmission does not interfere with estrogen priming or sensitivity of hypothalamic cells to progesterone.
Play behavior and occupational therapy.

The effectiveness of treatment methods on a person's ability to carry out occupational roles competently is of interest to occupational therapists. This case study demonstrated how play, as an occupational role of childhood and as a measure of competence, can be used to evaluate the effectiveness of occupational therapy that uses a sensory integrative approach. The positive changes in C.C.'s play behavior support the basic philosophy of sensory integration, which states that an increase in sensory integrative functions will improve competence (in this study, competence is defined as play), that is, that a person will have the ability to carry out occupational roles in an adaptive and competent manner. In addition, improvements in other areas, such as the organization and execution of self-care skills and improvements in gross and fine motor skills, provide further support to sensory integrative philosophy. Further exploration of these concepts would add to a growing body of knowledge aimed at the documentation of the effectiveness and efficacy of occupational therapy interventions.
Optimization of SAM-based multilayer SERS substrates for intracellular analyses: the effect of terminating functional groups

Surface-enhanced Raman scattering (SERS) has become an attractive analytical tool for intracellular analyses due to its minimally invasive nature and molecular specificity. However, highly reproducible and optimized SERS substrates have been seen as a key to developing SERS as a reliable analytical methodology. This research focuses on optimizing self assembled monolayer (SAM)-based multilayer SERS substrates for a wide range of applications, including ultratrace detection of biomolecules within individual living cells. Multilayer SERS substrates are comprised of alternating layers of metal film and dielectric spacer cast on a monolayer of nanostructures. Using these substrates, varying degrees of SERS enhancement factors (EF) have been achieved, some as large as 10-fold relative to optimized single film over nanostructures substrates. To gain a mechanistic understanding of multilayered SERS enhancements, SAMs have been used to systematically vary spacer thickness. The results revealed spacer-dependent SERS EFs. To further the understanding of multilayer SERS enhancement, this work discusses the use of terminating functional groups in the optimization of SAM multilayer SERS substrates. SAMs having various functional groups were used as dielectric spacers to systematically vary the dielectric constant. To investigate the effect of the pH on the uniformity of the SAMs and their multilayer SERS enhancement, SAMs were formed in alkylthiol solutions of different pH and the subsequent SERS enhancement were evaluated. It was found that using alklythiol SAMs with appropriate terminating functional groups the SAM multilayer can achieve SERS EFs ranging between 10 8 and10 10 and the substrates yielded highly reproducible SERS signals. The effect of the pH on the SERS enhancement is selective on the type of the terminating functional group of the alkylthiol used for SAM formation.
Surface-Enhanced Raman Scattering from Substrates with Conducting or Insulator Overlayers: Electromagnetic Model Predictions and Comparisons with Experiment

Model electromagnetic (EM) calculations are presented of the surface-enhanced Raman scattering (SERS) intensities expected for gold and silver particles coated with conducting as well as insulating dielectric films, with the objective of assessing their thickness-dependent properties and hence the anticipated scope of such ''overlayer SERS'' tactics to chemically diverse interfacial materials. Most calculations refer to Raman enhancements at the film outer edge, relevant to species adsorbed on the overlayer. Spheroidal and spherical metal particles are treated by using the electrostatic approximation, with a first-order electrodynamic correction for ''radiation damping'', in vacuum and aqueous environments. The presence of simple insulating dielectric (such as organic) overlayers yields progressive decays in the calculated Raman enhancement factor, G, at the film edge with increasing thickness, d, throughout the visible optical region of experimental significance, even though the largest G values are necessarily obtained close to the plasmon resonance energy. These G-d dependencies are markedly milder than predicted for bare metal particles in water or vacuum, suggesting the potential broad-based analytical utility of nanoscale (~1-10 nm thick) molecular dielectric overlayers in SERS. Furthermore, Raman enhancements increasing with film thicknesses are typically obtained at locations close to the inner film edge, relevant to moieties imbedded in dielectric overlayers. Sharper G-d decays are predicted at the film edge of transition-metal overlayers, especially near the plasmon resonance; unlike dielectric insulators, the metal overlayers progressively ''quench'' the optical frequency-dependent enhancement at the film edge arising from substrate plasmon resonance. Reasonable agreement is obtained in comparison with the Raman intensity-thickness dependence measured for chemisorbed carbon monoxide on rhodium films electrodeposited onto gold. The model calculations can also account qualitatively for the nonmonotonic Raman intensity-thickness dependencies observed for phonon bands from semiconducting (cadmium chalcogenide) overlayers on gold, attributed to film-induced redshifts in the substrate plasmon resonance. More general implications for the analytical utility of ''overlayer SERS'' tactics are also pointed out.
Alkaline phosphatase from bovine mammary tissue: Purification and some molecular and catalytic properties

Abstract 1. 1. Alkaline phosphatase (EC 3.1.3.1.) from bovine mammary tissue was solubilized from the microsomal membranes by butanol treatment and purified 17,300-fold. using Sephadex G-200 gel filtration, ultrafiltration and concanavalin A affinity chromatography, to a final specific activity of 364 U/'mg protein. 2. 2. It had a minimum molecular weight of 70,500 daltons: a carbohydrate content of 30% based on glucose equivalents, and its absorption spectrum gave an A280/A260 ratio of 1.2.
Characterization of the Acyl Substrate Binding Pocket of Acetyl-CoA Synthetase†

AMP-forming acetyl-CoA synthetase [ACS; acetate:CoA ligase (AMP-forming), EC 6.2.1.1] catalyzes the activation of acetate to acetyl-CoA in a two-step reaction. This enzyme is a member of the adenylate-forming enzyme superfamily that includes firefly luciferase, nonribosomal peptide synthetases, and acyl- and aryl-CoA synthetases/ligases. Although the structures of several superfamily members demonstrate that these enzymes have a similar fold and domain structure, the low sequence conservation and diversity of the substrates utilized have limited the utility of these structures in understanding substrate binding in more distantly related enzymes in this superfamily. The crystal structures of the Salmonella enterica ACS and Saccharomyces cerevisiae ACS1 have allowed a directed approach to investigating substrate binding and catalysis in ACS. In the S. enterica ACS structure, the propyl group of adenosine 5'-propylphosphate, which mimics the acyl-adenylate intermediate, lies in a hydrophobic pocket. Modeling of the Methanothermobacter thermautotrophicus Z245 ACS (MT-ACS1) on the S. cerevisiae ACS structure showed similar active site architecture, and alignment of the amino acid sequences of proven ACSs indicates that the four residues that compose the putative acetate binding pocket are well conserved. These four residues, Ile312, Thr313, Val388, and Trp416 of MT-ACS1, were targeted for alteration, and our results support that they do indeed form the acetate binding pocket and that alterations at these positions significantly alter the enzyme's affinity for acetate as well as the range of acyl substrates that can be utilized. In particular, Trp416 appears to be the primary determinant for acyl chain length that can be accommodated in the binding site.
The stability of individual differences in behavior across experimental conflict situations

Abstract Four experimental conflict situations having theoretical implications have been reported upon with some frequency. The purpose of this study was to compare individual differences on a common measure, response latency, in order to determine the stability of behavior across these four conflict situations using a comparable latency measure. The results of this study do indicate that behavior in experimental conflict studies shows a stability of performance by individual subjects. There are also group mean differences between the four procedures that reflect situational contribution to conflict behavior.
On sufficient conditions for the sum of two weak closed convex sets to be weak closed

1. The question as to when the sum of two closed sets is closed arises naturally in applied mathematics and is of interest in its own right. For subsets of an infinite dimensional space, answers to this question have been given by Choquet [1], Ky Fan [3], Dieudonn+ [2] and more recently by Jameson [4]. Ky Fan, in particular, has shown that the sum of two weakly closed convex subsets of a locally convex topological vector space is weakly closed under a condition that takes account of the mutual position of the two sets. In this note, we offer another sufficient condition of this genre for subsets in the dual of a locally convex topological vector space. Despite its simplicity, this result seems to have been overlooked in the literature. We also give simple examples which bring out the difference between our sufficient condition and those of the others. It is worth mentioning that our result is directly inspired by a problem in mathematical economies, see [5]. 2. Let (E, z) be a real, Hausdorff locally convex vector space and E' its topological dual, i.e., the space of all z-continuous linear functions on E. a (E', E) denotes the weak �9 topology on E'. Following [6, Definition 12-3-7], we say that E is strictly hypercomplete if for any S c E', S n U ~ is weak �9 compact implies S is weak �9 closed, where U ~ is the polar of any neighborhood of zero in E. We can now state
Molecular physiology of gap junction channels.

SUMMARY 1. Cloning and sequencing of cDNA encoding gap junction proteins (connexins) has allowed analysis of tissue- and stage-specific patterns of expression as well as the manipulation of expression of both wild-type and mutant connexin proteins. 2. These studies reveal that the 13 rodent connexins have different biophysical properties, such as unitary conductance and permeability/selectivity, are differentially sensitive to various gating stimuli and couple to one another with variable affinity. Moreover, the physiological roles of gap junction channels are being revealed, as both genetic and epigenetic human diseases are ascribed to aberrant gap junction expression, and as animal models are generated by genetic manipulation. 3. This symposium brought together physiological insights achieved through the use of molecular techniques, resulting in novel appreciation of the roles of gap junction channels in normal and pathological tissue function.
Chronic Ethanol Exposure Enhances Signaling Through Muscarinic Receptors Expressed by cRNA Injection in Xenopus Oocytes: Implications for Mechanism of Action

The molecular mechanisms underlying the cerebral symptoms of ethanol withdrawal syndrome are poorly understood. In addition to ethanol's effect on GABA and NMDA receptors, ethanol affects muscarinic acetylcholine signaling. This interaction has attracted attention because of the importance of muscarinic signaling in consciousness. Chronic ethanol exposure increases muscarinic receptor binding. Increased transcription of receptor message has been suggested as the underlying mechanism, but this hypothesis has not been tested directly. Therefore, we studied the effects of ethanol on muscarinic signaling in a model that bypasses transcription of muscarinic receptor genes. We expressed rat m1 muscarinic receptors by cRNA microinjection in Xenopus oocytes. Cells were voltage-clamped at -70 mV and effects of prolonged (24, 48, and 72 hr) exposure to ethanol (25, 50, and 100 mM) on methylcholine-induced calcium-activated Cl- currents were determined. Effects of prolonged ethanol exposure on currents induced by stimulation of lysophosphatidate receptors, direct G protein activation, or inositol trisphosphate receptor activation were studied as well. Prolonged ethanol exposure enhanced methylcholine (or lysophosphatidate-)-induced currents in a time- and concentration-dependent manner. Thus, enhanced muscarinic gene transcription is not required for ethanol enhancement of muscarinic signaling. Lack of ethanol effect on inositol trisphosphate-induced signaling suggests that intracellular signaling systems downstream of phospholipase C are not involved. In contrast, currents induced by direct G protein stimulation were enhanced significantly. Therefore, one potential site of ethanol's action on muscarinic signaling is upregulation of the associated G protein or enhancement of its functioning.
Aerobic and anoxic biodegradation of benzoate: stability of biodegradative capability under endogenous conditions

Aromatic organic compounds are degraded by different enzyme systems under aerobic and anoxic conditions. This raises the question of how bacteria in biological nitrogen removal processes, which cycle bacteria between aerobic and anoxic environments, regulate their enzyme systems for degrading aromatic compounds. As a first step in answering that question, mixed microbial communities were grown on benzoate as sole carbon source in chemostats under fully aerobic and fully anoxic (nitrate as the electron acceptor) conditions and tested for their ability to degrade benzoate in batch reactors after exposure to aerobic or anoxic conditions in the absence of substrate. Aerobically grown biomass retained its ability to degrade benzoate without loss of activity after endogenous exposure to aerobic conditions for up to 8 h. However, when exposed to anoxic conditions, the biomass rapidly lost its aerobic benzoate degrading activity, retaining less than 20% of the initial activity after 8 h. Similarly, anoxically grown biomass retained its ability to degrade benzoate without loss of activity after endogenous exposure to anoxic conditions for up to 8 h. However, when anoxically grown biomass was exposed to aerobic conditions, only 20% of its initial activity was lost in the first 2 h, after which the remaining activity was retained for up to 8 h. Similar experiments with pyruvate showed that the 20% loss of activity was not due to loss of denitrifying enzymes, suggesting that it was due to loss of catabolic enzymes.
Two-Step Water Splitting Using Mixed-Metal Ferrites: Thermodynamic Analysis and Characterization of Synthesized Materials

We report a comprehensive thermodynamic analysis of thermal oxidation−reduction cycles for producing hydrogen that use metal ferrites with the spinel structure (MFe2O4; M = Fe, Co, Ni, and Zn) as the redox material. Solution phases (both solid and liquid) were included in the calculations as well as the expected line compounds. Omitting solution phases, whose existence is experimentally well-documented, has a very significant impact upon the results of the calculations. Thermodynamic modeling of the three important material-related aspects of the process was performed, including synthesis of the ferrite materials from bulk oxides, thermal reduction at high temperatures, and reoxidation by reaction with steam. An experimental investigation of the NixFe3−xO4 system was performed to provide compositional data for comparison to model predictions. The results indicate that the Fe/Ni ratio, thermal reduction reaction kinetics, and the specifics of the cooling process affect the composition of the synthesized ma...
The Effect of Poverty on Child Development and Educational Outcomes

Poverty affects a child's development and educational outcomes beginning in the earliest years of life, both directly and indirectly through mediated, moderated, and transactional processes. School readiness, or the child's ability to use and profit from school, has been recognized as playing a unique role in escape from poverty in the United States and increasingly in developing countries. It is a critical element but needs to be supported by many other components of a poverty-alleviation strategy, such as improved opportunity structures and empowerment of families. The paper reviews evidence from interventions to improve school readiness of children in poverty, both in the United States and in developing countries, and provides recommendations for future research and action.
α-Acylamino radical cyclizations using allenes and vinylsilanes as addends: applications to the synthesis of (+)-heliotridine and (-)-dihydroxyheliotridine

Abstract Total syntheses of the pyrrolizidine bases (+)-heliotridine ( 4 ) and (-)-dihydroxyheliotridane ( 5 ) from ( S )-3-acetoxysuccinimide are described. The syntheses of 4 and 5 revolve around free radical cyclizations involving the use of allenes and vinylsilanes, respectively, as addends.
Significance of marrow‐derived nicotinamide adenine dinucleotide phosphate oxidase in experimental ischemic stroke

Objective Reperfusion after stroke leads to infiltration of inflammatory cells into the ischemic brain. NADPH oxidase (NOX2) is a major enzyme system which generates superoxide in immune cells. We studied the effect of NOX2 derived from the immune cells in the brain and in blood cells in experimental stroke.
Meter in Theodore Roethke's MY PAPA’S WALTZ

Since the publication in 1950 of Kenneth Burke's essay “The Vegetal Radicalism of Theodore Roethke,” psychological and biographical approaches have underlain critical responses to Roethke's poetry....
Voltammetric Study of an Unusual Dimer/Monomer Redox System Involving a Chromium(III) Complex of a Tridentate CNN Ligand

In an attempt to prepare an alkylidene complex of chromium, the metallacycle, Cp * Cr(L)(CH 2 ) 2 Si(CH 3 ) 2 (L=THF), was treated with 2,2'-bipyridine. Instead of producing the desired trimethylsilylmethylidine complex, a new complex (η 5 -(pentamethylcyclopentadienyl)(2(2,2-dimethyl-2-silapropyl)-1,2-dihydro[2,2']bipyridine-1,3-diyl)chromium(III), 1) with a methylene bridge between silicon and the C 2 carbon of the bidentate 2,2'-bipyridine ligand was formed. The modified bipyridine ligand contains one carbon and two nitrogen donor atoms (CNN ligand). When 1 was treated with [Cp 2 Fe] + [PF 6 ] - , oxidative dimerization occurred giving a dimer dication (2) linked at the C 3 carbon atoms of each 2,2'-bipyridine ligand. This dimer was isolated as the hexafluorophosphate salt. In the present work the electrochemical behavior of 1 and 2 has been explored and it has been shown that anodic oxidation of 1, like the chemical oxidation, produces 2 by way of dimerization of an initially formed transient cation. The dimerization rate constant was 2 × 10 4 M -1 s -1 and the equilibrium constant for dimerization must exceed 5 × 10 6 M -1 . Studies of the cathodic reduction of 2 show that it undergoes an overall two-electron reduction giving mainly 1 as product. The reduction apparently proceeds by one-electron reduction to a detectable intermediate monocation that dissociates to 1 and the cation of 1 which in turn is reduced to 1. It was also found that 2 undergoes an irreversible two-electron oxidation, the products of which were not identified.
Emotional Expressions in Antismoking Television Advertisements: Consequences of Anger and Sadness Framing on Pathways to Persuasion

The authors conducted an experiment among U.S. college students (N = 115) to assess the effects of anger- and sadness-framed television antismoking advertisements on viewers' emotional response, impressions of the speaker, source likability, and empathy toward the speaker. The study was based on the fundamental assumptions of discrete emotions and was operationalized using the principles of universal facial expressions. The authors also constructed a path model to investigate how these variables predicted one's attitude toward smoking, attitude toward the tobacco industry, and intentions to smoke. Supporting study hypotheses, the anger-framed message increased the perceived dominance of the speaker relative to the other conditions. Perceived dominance, in turn, was negatively associated with smoking attitudes and, indirectly, smoking intentions. Contrary to study hypotheses, the sadness-framed message did not increase sad emotional responses, source likability, or empathy relative to the no emotion-framed...
Quantum confinement controlled photocatalytic water splitting by suspended CdSe nanocrystals

The photocatalytic hydrogen production of CdSe nanocrystals (1.75–4.81 nm) in the presence of aqueous sodium sulphite depends exponentially on the bandgap of the particles, confirming that the material’s activity is controlled by the degree of quantum confinement.
Telescopic replication in hierarchically structured process-control programs

Presents a hierarchical control structure incorporating telescopic replication for providing cost-effective redundancy for nodes providing centralized control. The lowest-level nodes of the hierarchy are designed to be inherently fault-tolerant. The higher-level nodes formulate optimal strategies and coordinate lower-level activities. Telescopic replication yields a good performance/cost ratio and allows the system to adapt to failures of higher-level nodes gradually, without the use of backward recovery. >
Conservation and variation in the feeding mechanism of the spiny dogfish squalus acanthias

Changes in the feeding mechanism with feeding behavior were investigated using high-speed video and electromyography to examine the kinematics and motor pattern of prey capture, manipulation and transport in the spiny dogfish Squalus acanthias (Squalidae: Squaliformes). In this study, Squalus acanthias used both suction and ram behaviors to capture and manipulate prey, while only suction was used to transport prey. The basic kinematic feeding sequence observed in other aquatic-feeding lower vertebrates is conserved in the spiny dogfish. Prey capture, bite manipulation and suction transport events are characterized by a common pattern of head movements and motor activity, but are distinguishable by differences in duration and relative timing. In general, capture events are longer in duration than manipulation and transport events, as found in other aquatic-feeding lower vertebrates. Numerous individual effects were found, indicating that individual sharks are capable of varying head movements and motor activity among successful feeding events. Upper jaw protrusion in the spiny dogfish is not restricted by its orbitostylic jaw suspension; rather, the upper jaw is protruded by 30 % of its head length, considerably more than in the lemon shark Negaprion brevirostris (Carcharhinidae: Carcharhiniformes) (18 %) with its hyostylic jaw suspension. One function of upper jaw protrusion is to assist in jaw closure by protruding the upper jaw as well as elevating the lower jaw to close the gape, thus decreasing the time to jaw closure. The mechanism of upper jaw protrusion was found to differ between squaliform and carcharhiniform sharks. Whereas the levator palatoquadrati muscle assists in retracting the upper jaw in the spiny dogfish, it assists in protruding the upper jaw in the lemon shark. This study represents the first comprehensive electromyographic and kinematic analysis of the feeding mechanism in a squaliform shark. Summary
Tropical forests and global warming: slowing it down or speeding it up?

The world's tropical forests take up and emit large amounts of carbon (C) through photosynthesis and respiration. Their response to global changes in the atmosphere and climate could therefore act as a feedback. Only recently has research been focused on the possibility that tropical forests may not be in C balance. There is currently a vigorous debate about whether these ecosystems might be accelerating or slowing down the rate of atmospheric CO2 accumulation, and thus global warming. The evidence is thin in either direction, and in some cases highly uncertain. Some findings raise the possibility that higher temperatures could make tropical forests increasing C sources to the atmosphere – a positive feedback effect. To project where our climate is headed, it is critical to resolve two questions: how tropical forests are reacting to changing climate, atmosphere, and land use, and how they will continue to respond over the coming decades.
On the steady-state phase distribution in a hexagonally coupled oscillator array

The distribution of the phase of the oscillations of a set of mutually injection locked electronic oscillators is investigated for the case of a hexagonal nearest neighbor coupling topology. It is shown that planar distributions are not, in general, steady-state solutions of the system of nonlinear differential equations governing the system. An exact steady-state solution of the equations is obtained and shown to be planar only for six discrete azimuth angles. The degree of deviation from a planar distribution is determined and its impact on the directivity of a phased array excited by the oscillator output signals is estimated.
Easily testable DCVS multiplier

Clocked differential cascode voltage switch (DCVS) circuits are dynamic CMOS circuits which have the advantage of being protected against test-set invalidation due to circuit delays. A C-testable DCVS design of a carry-save parallel multiplier is presented. This design is C-testable with only six test vectors which detect all detectable stuck-at, stuck-on, and stuck-open faults in the circuit. The hardware needed for an n*n multiplier consists of n(n-1) full-adders, a summand generator consisting of n/sup 2/ 2-input AND gates, as well as (at most) four extra 2-input AND gates to enhance the controllability of the circuit. An additional controllable input t is required. The design of the multiplier is discussed. The set of vectors to test the individual building blocks of the multiplier is presented. The input assignments to the DCVS multiplier, which result in the application of the appropriate tests to each module, are discussed, and the validity of the test set for detecting the detectable single stuck-at, stuck-open, and stuck-on faults is proved. >
OBDD-Based Sectionalizing Strategies for Parallel Power System Restoration

After a power system is subjected to a blackout, parallel restoration is an efficient means to speed up the restoration process. The system sectionalizing strategy consists of determining the proper splitting points to sectionalize the entire blackout area into several subsystems, so that parallel restoration can be carried out within the subsystems. For a large-scale power system, this system sectionalizing problem is quite complicated when considering black-start constraints, generation/load balance constraints, and voltage stability constraints. This paper presents an ordered binary decision diagram (OBDD) -based system sectionalizing method, by which the splitting points can be found quickly. Simulation results on the IEEE 118-bus test systems show that the method can successfully sectionalize the system into subsystems satisfying black-start constraints, generation/load balance constraints, and voltage stability constraints.
Distinct element method for multiscale modeling of cross-linked carbon nanotube bundles: From soft to strong nanomaterials

Predicting the impact of cross-links on the mechanics of carbon nanotube-based materials is a challenging endeavor, as the micro- and nanostructure is composed of continuous nanofibers, discontinuous interfaces, and covalent bridges. Here we demonstrate a new modeling solution in the context of the distinct element method (DEM). By representing nanotubes as bonded cylinder segments undergoing van der Waals adhesion, viscous friction, and contact bonding, we are able to simulate how cross-linking transforms a soft bundle into a strong one. We predict that the sp3- sp cross-links formed by interstitial carbon atoms can improve the tensile strength by an order of magnitude, in agreement with experiment and molecular dynamics simulations. The DEM methodology allows performing the multiscale simulation needed for developing strategies to further enhance the mechanical performance.
Haptic Attributes and Human Motor Skills

Most human fine motor skills involve the use of a tool to complete the given task. The task to be completed is often defined in terms of some desired trajectory and humans generate certain forces to achieve the desired trajectory. In this paper we describe our efforts to experimentally and theoretically classify forces associated with these skilled tasks. The idea is then to develop a system that can capture and playback exhibition of skill through haptics from person to person. Our preliminary results from experiments show that the forces generated by an individual are unique for a given task. Furthermore, for a given person, these forces show little variance over repeated exhibition of the same task. A virtual writing simulator was used to collect data from human subjects. The significance of this research is that not only was the forces generated by a person for a given skill unique, but is also verifiably different from another human subject performing the same task.
Uses and gratifications on social networking sites: Analysis of use and value of social networking sites for three types of social capital on college students

Social networking sites (SNS), such as Facebook and LinkedIn, have recently emerged as popular media worldwide. The rapid adoption of SNS by college students in the United States raises many questions. Why do youths like SNS? How do they use them? Will these SNS activities replace or complement face-to-face relationships? To address these questions, this research provides a quantitative examination of college students’ uses and gratifications of SNS, with a focus on social capital. More specifically, it examines how individuals’ perceived value of social capital drives the generation of user-created content, and how gratifications obtained from SNS are different from other media. SNS usage and satisfaction were explored as the consequences of social capital motives toward SNS. This study found that different types of social capital, especially “bridging” social capital, impacted students’ use of SNS. Also the most obvious finding in this study is that SNS did not substitute for face-to-face relationships, but instead assisted students’ communication with different connections. User-created content enables users to create and publish different kinds of media content to make visible communication. Additionally, users may perform different activities on SNS for various reasons and motivations. Users’ social interactions are undergoing a true revolution, and social capital has been tightly related to today’s SNS. Another major finding was that the motivations for obtaining “bonding,” “bridging” and “linking” social capital had affected individuals’ user-created content activity.
Potential of antifeedants to control larval feeding of selected Neodiprion sawflies (Hymenoptera: Diprionidae).

Antifeedants for controlling larval feeding of several Neodiprion sawflies were evaluated in laboratory and field studies. Nine commercially available insect antifeedants and a hexane extract of the juvenile foliage of jack pine, Pinus banksiana Lambert, were tested on larvae of six species. In laboratory bioassays larvae exhibited varying sensitivity to antifeedants; generally species with monophagous or restricted oligophagous feeding habits were most sensitive. In the laboratory the Swaine jack pine sawfly, Neodiprion swainei Middleton, had severely restricted feeding, development, survival, and fecundity. Triphenyltin hydroxide was toxic to N . swainei and to European pine sawfly, N . sertifer (Geoffroy). In field tests certain antifeedants disrupted N . swainei feeding and development. The colonial behavior of larvae often was disrupted and solitary larvae fell from trees or wandered on twigs. Colony disruption by most antifeedants was temporary and many larvae resumed feeding.
Application of Millimeter-Wave Radiometry for Remote Chemical Detection

Passive millimeter-wave systems have been used in the past to remotely map solid targets and to measure low-pressure spectral lines of stratospheric and interstellar gases; however, its application to pressure-broadened spectral line detection of industrial emissions is new. We developed a radiative transfer model to determine feasibility and system requirements for passive millimeter-wave spectral detection of terrestrial gases. We designed and built a Dicke-switched multispectral radiometer in the 146-154-GHz band to detect nitric oxide (NO), a prototypical gas of nuclear fuel processing operations. We first tested the spectral detection capability of the radiometer in the laboratory using a gas cell and then field tested it at the Nevada test site at a distance of 600 m from a stack that released hot plumes of NO and air. With features such as Dicke-switched integration, frequent online calibration, and spectral baseline subtraction, we demonstrated the feasibility of remote detection of terrestrial gases by a ground-based radiometer.
Ligand redox non-innocence in the stoichiometric oxidation of Mn2(2,5-dioxidoterephthalate) (Mn-MOF-74).

Unsaturated metal sites within the nodes of metal–organic frameworks (MOFs) can be interrogated by redox reagents common to small molecule chemistry. We show, for the first time, that an analogue of the iconic M2(2,5-dioxidoterephthalate) (M2DOBDC, MOF-74) class of materials can be stoichiometrically oxidized by one electron per metal center. The reaction of Mn2DOBDC with C6H5ICl2 produces the oxidized material Cl2Mn2DOBDC, which retains crystallinity and porosity. Surprisingly, magnetic measurements, X-ray absorption, and infrared spectroscopic data indicate that the Mn ions maintain a formal oxidation state of +2, suggesting instead the oxidation of the DOBDC4– ligand to the quinone DOBDC2–. These results describe the first example of ligand redox non-innocence in a MOF and a rare instance of stoichiometric electron transfer involving the metal nodes. The methods described herein offer a synthetic toolkit that will be of general use for further explorations of the redox reactivity of MOF nodes.
Identity Processes and Memory Controllability in Middle and Later Adulthood

Memory is a salient area of functioning in adulthood known to be influenced by beliefs about performance. To date, individual variations in memory beliefs have not been systematically examined. The present study used hierarchical linear regressions to examine the relationship between Memory Controllability Index (MCI) subscales and identity processes in 250 adults (M = 58.01, 40 to 91 years), controlling for age, gender, and self-rated health. The ability to integrate age-related changes into identity was positively related to MCI scales measuring assessment of ability, potential to improve memory, and belief in the value of using memory strategies. The identity scale measuring negative age-related changes was related to lower memory self-assessment, ability to improve, and the belief that memory decline is inevitable. Contrary to expectation, the tendency to resist making changes in identity was not related to controllability. Findings support the utility of understanding memory-related beliefs in middle...
An Ethological Perspective on Homosexuality during Adolescence

An ethological perspective is presented as an alternative to traditional developmental approaches to adolescence. From an evolutionary point of view, the onset of reproductive capability during adolescence marks the significance of this time during the life course. Thus, the apparent anomaly of male and female youth "preferring" not to engage in heterosexual activities that have the potential to maximize genetic fitness but to participate in homosexual activities that do not have the same adaptive repercussion poses a challenge for an ethological perspective to interpret. To better understand an ethological perspective, basic ethological principles are applied to the emergence and expression of homosexuality during adolescence. First, evidence bearing on the genetic etiological under-pinnings of homosexuality within humans is reviewed through an examination of (a) behavioral genetic studies and (b) hormonal research. Next, adaptive considerations are presented, in particular the prevalence of homosexual behavior among various animal species and human societies, as well as evolutionary pressures that maintain a stable level of homosexuality in the human population. Balanced polymorphism and kin selection are reviewed as answers to the ultimate or functional question. Finally, the "naturalness" of adolescent homosexuality as an outcome of an ethological perspective is proposed. Homosexuality is thus presented as a sexual orientation that is not so much a matter of choice but of biological necessity. Language: en
Cause and control: education and training of professional industrial hygienists for 2020.

By the year 2020, the environmental movement will have established a recognized profession, expert at studying deleterious effects in the working and public domains. Environmental science practitioners will be better able to identify and relate ill effects to the presence of adverse agents in the environment; they will not, however, necessarily be skilled at developing systems for control. Industrial hygienists should provide the unique and special skills required to establish economically optimum control systems. Industrial hygiene should by then have been redefined to emphasize this critical role of its professional members. A new orientation for education is therefore proposed to provide a sound basis for the professional needs of industrial hygienists who should be at the peak of their careers in 2020. Members of the profession should then be the leaders in research on, and practice of, the science and engineering of design, installation, and monitoring of control systems for occupational and environm...
Facial expression analysis for predicting unsafe driving behavior

A system for tracking driver facial features aims to enhance the predictive accuracy of driver-assistance systems. The authors identify key facial features at varying pre-accident intervals and use them to predict minor and major accidents.
Röntgens Vortrag „Über eine neue Art von Strahlen“ vor der Physikalisch-Medizinischen Gesellschaft zu Würzburg am 23. Januar 1896

Am 13. Januar 1896 hielt Rontgen den im 5. Kapitel ausfuhrlicher besprochenen Vortag vor Kaiser Wilhelm II., scheint aber sonst in keiner Weise uber seine Entdeckung gesprochen zu haben, bis zu jenem denkwurdigen Vortrag in der Sitzung der Wurzburger Physikalisch-Medizinischen Gesellschaft am Abend des 23. Januar 1896.
Towards Involvement of Interactions of Nucleic Acid Bases with Minerals in the Origin of Life: Quantum Chemical Approach

This review describes the results of studies of interactions of nucleic acid bases with water, cations and minerals. It focuses on three areas investigated computationally: (1) carbon fixation cycle; (2) 1-methylcytosine tautomerism due to presence of water and cation; (3) adsorption of thymine and uracil on clay minerals. It reveals how the individual reactions responsible for the generation of acetic acid on iron-nickel sulfide surfaces as catalysts could have operated to produce carboxylic acids from carbon oxide and water. The importance of these results in terms of a primordial chemistry on iron-nickel sulfide surfaces is discussed. The interaction with the Na+ cation has a dramatic effect on equilibrium between oxo-amino and oxo-imino tautomers of methylcytosine and can lead to a decrease in concentration of imino-oxo tautomer (present in the cell during DNA synthesis) responsible for the point mutations in DNA during formation of a mismatched base pair. Thymine and uracil interact quite strongly with the kaolinite mineral surfaces but uracil is slightly better stabilized than thymine on these clays. The adsorption leads to their structural changes, which are induced by the deposition way and are driven by the surface potential. Explicit addition of water molecule changes only slightly its adsorption properties, comparing the presence of the sodium cation.
Puzzled: Breaking chocolate bars

Welcome to three new puzzles. Solutions to the first two will be published next month; the third is (as yet) unsolved. In each, the issue is how your intuition matches up with the mathematics.