cssi/SciSciGPT-SciSciNet huggingface dataset:
Optimal extravascular dosing intervals.

An explicit formula is presented for simple calculations of the dosing time, tau, that results in a steadystate peak-to-trough ratio of 2 in extravascular dosings. Contrary to other formulae presented, the calculations are guaranteed to be well bound in the percentage error (less than 1%) for any parameter value combination. It is shown that the biexponential dosing interval problem can be transformed into a general, dimensionless problem enabling a global error analysis in the approximation. The proposed formula is demonstrated in the calculation of an “optimal” dosing interval for quinidine. An algorithm and FORTRAN computer program OPTAU for exact calculation of tau and dosing simulations is also demonstrated in the quinidine example.
Development of pH- and time-dependent oral microparticles to optimize budesonide delivery to ileum and colon

A microparticulate system consisting of non-enzymatically degrading poly(dl-lactide-co-glycolide) (PLGA) core and delivering budesonide site specifically to distal ileum and colon was developed. Budesonide-loaded microparticles were fabricated using solvent evaporation technique and formulation variables studied included different molecular weight grades of PLGA polymer as well as concentration of polymer, surfactant and drug. Eudragit® S-100, an enteric polymer, was then used to form a coating on the surface of budesonide-loaded PLGA microparticles for site specific delivery to the distal ileum and colon. Budesonide-loaded PLGA microparticles prepared from various formulation parameters showed mean encapsulation efficiencies ranging between 50% and 85% and mean particle size ranging between 10 and 35 μm. In vitro release kinetics studies showed a biphasic release pattern with an initial higher release followed by a slower drug release. Increasing polymer and surfactant concentrations exhibited sharply contrasting drug release profiles, with increasing polymer concentrations resulting in a lower drug release and vice versa. The budesonide-loaded PLGA microparticles coated with Eudragit® S-100 coating showed a decrease in entrapment efficiency with an accelerated in vitro drug release. Moreover, complete retardation of drug release in an acidic pH, and, once the coating layer of enteric polymer was dissolved at higher pH (7.4 and 6.8), a controlled release of the drug from the microparticles were observed. From the results of this investigation, the application of double microencapsulation technique employing PLGA matrix and Eudragit® S-100 coating shows promise for site specific and controlled delivery of budesonide in Crohn's disease.
TinySPICE: a parallel SPICE simulator on GPU for massively repeated small circuit simulations

In nowadays variation-aware IC designs, cell characterizations and SRAM memory yield analysis require many thousands or even millions of repeated SPICE simulations for relatively small nonlinear circuits. In this work, we present a massively parallel SPICE simulator on GPU, TinySPICE, for efficiently analyzing small nonlinear circuits, such as standard cell designs, SRAMs, etc. In order to gain high accuracy and efficiency, we present GPU-based parametric three-dimensional (3D) LUTs for fast device evaluations. A series of GPU-friendly data structures and algorithm flows have been proposed in TinySPICE to fully utilize the GPU hardware resources, and minimize data communications between the GPU and CPU. Our GPU implementation allows for a large number of small circuit simulations in GPU's shared memory that involves novel circuit linearization and matrix solution techniques, and eliminates most of the GPU device memory accesses during the Newton-Raphson (NR) iterations, which enables extremely high-throughput SPICE simulations on GPU. Compared with CPU-based TinySPICE simulator, GPU-based TinySPICE achieves up to 138X speedups for parametric SRAM yield analysis without loss of accuracy.
Studies on the mechanism of killing of Bacillus subtilis spores by hydrogen peroxide.

Aims: To determine the mechanism of killing of Bacillus subtilis spores by hydrogen peroxide. Methods and Results: Killing of spores of B. subtilis with hydrogen peroxide caused no release of dipicolinic acid (DPA) and hydrogen peroxide-killed spores were not appreciably sensitized for DPA release upon a subsequent heat treatment. Hydrogen peroxide-killed spores appeared to initiate germination normally, released DPA and hydrolysed significant amounts of their cortex. However, the germinated killed spores did not swell, did not accumulate ATP or reduced flavin mononucleotide and the cores of these germinated spores were not accessible to nucleic acid stains. Conclusions: These data indicate that treatment with hydrogen peroxide results in spores in which the core cannot swell properly during spore germination. Significance and Impact of the Study: The results provide further information on the mechanism of killing of spores of Bacillus species by hydrogen peroxide.
OCT III imaging of whiplash maculopathy

Sir, I read with interest the remarkable description of whiplash maculopathy in a 24-year-old woman following a motor vehicle accident.1 The authors point out that the patient noted a paracentral scotoma within hours of the accident. During the examination and on visual field testing 6 months later, a nasal parafoveal annular whitish lesion was noted and the scotoma could be documented by visual field assessment with laser beam and a Maddox cross, and quantified Octopus automated perimetry (10° centromacular field). Furthermore, the authors describe a change on optical coherence tomography (OCT) at the vitreoretinal interface. After a careful review of the imaging, including the OCT, I note an additional finding that may be a more likely cause of the scotoma in this patient. The OCT image demonstrates a severe disorganization of the inner segment–outer segment (IS–OS) retinal pigment epithelial (RPE) layer signals. Parafoveally, on the side closest to the visual field images in the composite figure, and presumably representing the nasal macula, the outer retina-RPE layers are not separately visible. Specifically, the IS–OS junction is obscured in this area, while it is distinctly visible elsewhere on this OCT image. The integrity of the IS–OS junction has increasingly become recognized as important for visual function. Reports in several conditions have shown that abnormalities in this layer are associated with poor visual function in the abnormal region, with decreased measured acuity or corresponding scotomata.2, 3, 4 Reinterpretation of the OCT image would thus suggest that the cause of the scotoma in this case of whiplash maculopathy may be disruption of the outer segment architecture, and not a small area of increased reflection at the vitreoretinal junction. This interpretation is supported by the findings of Parsons et al in an autopsy case of whiplash maculopathy, which demonstrated the pathologic features of retinoschisis between the photoreceptor nuclei and the intact, but folded, photoreceptor inner and outer segments and RPE detachment.5 This alternative interpretation of the OCT image may more plausibly explain the scotoma in this patient and in whiplash maculopathy in general.
Exact solution to a strongly coupled Hubbard model in one dimension for high-Tc superconductors.

A Hamiltonian for the motion of oxygen holes strongly coupled to the Cu spins in a one-dimensional (1D) Cu-o lattice is solved exactly for all dopings. This Hamiltonian retains the dominant O-hole hopping term, that is, spin-exchange hopping of the hole spin with the intervening Cu spin and neglects the weaker non-spin-exchange hopping term. The excitations naturally separate into two independent quasiparticles: spinons and holons. It is this Hamiltonian that should be taken as the correct zeroth-order Hamiltonian from which perturbation theory should be applied
Red Flints in the Chalk

ARE red flints common in the Chalk? A portion of our Colege farm lies on a gentle slope on the Upper Chalk, which rises westward from the banks of the Hampshire Avon. On the higher parts of this slope black flints are excessively abundant, so much so that after sheep have been folded on the land, the fields present the appearance of a newly macadamised road, and the flints are picked up and put into heaps until an opportunity offers to use them for road-metal; in the course of a year they “grow” again as thickly as before. But one field on a ridge near the foot of the slope is remarkable for the number of red flints it contains; on the dusty soil they look just like bits of broken earthenware, and might at first fail to attract attention. Their size is much less than the average size of the black flints; some are rounded and some angular, others almost flake like. As to the frequency of their occurrence, I found I was able to pick up at least one at every step I took.
Photorefractive holographic lenses and applications for dynamic focusing and dynamic image shifting

Wavelength-multiplexed reflective holographic lenses were recorded in a 1-mm-thick Fe-doped LiNbO3 crystal. A simple theoretical model based on Kogelnik’s coupled-wave theory and Kuktarev’s photorefractive-material equations was used to characterize the photorefractive lenses in terms of Bragg-limited field of view, optimum space-bandwidth-product, and wavelength selectivity. Experimental measurement verified the theoretical calculations. An f/3 lens was recorded, and nearly aperture-limited diffraction performance was observed. Applications of wavelength-multiplexed photorefractive lenses were shown by demonstration of dynamic focusing and lateral image shifting.
The Effects of Spatial Heterogeneity and in vivo Crowding on the Lac Genetic Circuit

Standard deterministic and stochastic models used to explore the dynamics of cellular biochemical networks typically ignore spatial degrees of freedom (by assuming the cell is well-stirred). Spatial heterogeneity has been neglected due to the lack of both data regarding cellular localization and computational methodologies to simulate such models. Advances in in vivo imaging techniques, including cryo-electron tomography and single-molecule fluorescence microscopy, have begun to reveal the organization and dynamics of biomolecules inside the cell. Likewise, graphics processing units (GPUs) now provide the computational power to perform three-dimensional simulations of cell-scale models.Here, the effects of incorporating spatial information and molecular crowding into a stochastic model of the lactose utilization genetic circuit are reported. We use our recently developed lattice-based Monte Carlo simulation technique [1] to sample the reaction-diffusion master equation describing the lac circuit in an Escherichia coli cell. Parameters are obtained from published in vivo single molecule studies. By comparing to the well-stirred model, it is shown that spatial degrees of freedom introduce a source of noise into the circuit. Such spatial noise is a component of the extrinsic noise of a genetic system and we put bounds on its contribution. In certain fluctuating environments, spatial noise is found to influence the switching properties of the circuit leading to population distributions that cannot be predicted using well-stirred models. Finally, the model suggests new single molecule experiments to probe the lac circuit and provides estimates of the spatial and temporal resolution required. The integration of lattice microbe models with systems biology descriptions of cellular networks is also discussed.[1] Roberts, Stone, Sepulveda, Hwu, and Luthey-Schulten, “Long time-scale simulations of in vivo diffusion using GPU hardware”, In The Eighth IEEE International Workshop on High-Performance Computational Biology (2009).
Treatment Preferences Among Depressed Primary Care Patients

OBJECTIVE: To understand patient factors that may affect the probability of receiving appropriate depression treatment, we examined treatment preferences and their predictors among depressed primary care patients.
Functional genomics of pollen tube-pistil interactions in Arabidopsis.

The pollen tube represents an attractive model system for functional genomic analysis of the cell–cell interactions that mediate guided cellular growth. The pollen tube extends through pistil tissues and responds to guidance cues that direct the tube towards an ovule, where it releases sperm for fertilization. Pollen is readily isolated from anthers, where it is produced, and can be induced to produce a tube in vitro. Interestingly, pollen tube growth is significantly enhanced in pistils, and pollen tubes are rendered competent to respond to guidance cues after growth in a pistil. This potentiation of the pollen tube by the pistil suggested that pollen tubes alter their gene-expression programme in response to their environment. Recently, the transcriptomes of pollen tubes grown in vitro or through pistil tissues were determined. Significant changes in the transcriptome were found to accompany growth in vitro and through the pistil tissues. Reverse genetic analysis of pollen-tube-induced genes identified a new set of factors critical for pollen tube extension and navigation of the pistil environment. Recent advances reviewed in the present paper suggest that functional genomic analysis of pollen tubes has the potential to uncover the regulatory networks that shape the genetic architecture of the pollen tube as it responds to migratory cues produced by the pistil.
Stationary source combustion: an R & D update.

(1976). Stationary Source Combustion: An R&D Update. Journal of the Air Pollution Control Association: Vol. 26, No. 2, pp. 111-115.
Postprocedural endophthalmitis: a review

The prevalence of postprocedural endophthalmitis has increased in recent years, due in part to a wider range of indications for ophthalmic procedures, better access to treatments and therefore an increase in the overall number of surgical interventions being performed. Although postprocedural endophthalmitis is a rare event, endophthalmitis is always a devastating complication for both the patient and surgeon. Prompt diagnosis and effective treatment are necessary to increase the likelihood of a good visual outcome. In this review, the authors aim to summarize data of postprocedural endophthalmitis as it pertains to cataract extraction, intravitreal injection, vitrectomy, keratoprosthesis placement, corneal transplants, glaucoma surgery, scleral buckle, strabismus surgery and pterygium excision.
Late Holocene palaeogeomorphic reconstructions in the area of the Bay of Navarino: Sandy Pylos

Numerous archaeological sites dot the environs of the marine embayment at Navarino in the southwest Peloponnese. This paper presents palaeogeomorphic reconstructions necessary for the understanding of the late bronze age palace complex (“Nestor's Palace”) excavated by Blegen and provides a necessary topographic framework for the interpretation of human occupancy of the region during the last three millennia BC. Palaeoenvironmental data show that the epithet “Sandy Pylos” of Homer's Iliad, can be readily explained and justifiably attributed to this region. The pollen data presented appear to correlate well with the transgression-regression sequences developed from the geological information from subsurface boreholes.
Transformed Xenopus embryos as a transient expression system to analyze gene expression at the midblastula transition

Abstract The onset of transcriptional activity during embryogenesis in Xenopus laevis is at the 4000- to 8000-cell stage (stage 8–8.5) and is referred to as the midblastula transition (MBT). Most exogenous circular DNA that is microinjected into the fertilized egg also is expressed at the MBT. The transformed Xenopus embryo at these early stages was used as a transient expression system in order to determine the effects of (1) promoter strength, (2) physical conformation, (3) degree of replication, and (4) a regulatory molecule on the expression of an injected gene coding for chloramphenicol acetyl transferase. This gene linked to a relatively strong promoter (SV40 early promoter -pSV2CAT), a weak promoter (adenovirus early promoter -pE3CAT), or in circular or linear form is expressed at stage 8–8.5 following injection into fertilized eggs. pE3CAT coinjected with the E1a protein (enhances the transcription of the E3 promoter) is also expressed at stage 8.5, but expression is enhanced 2–7.6 fold. These data suggest that the inhibition of transcription prior to the MBT could not be perturbed by either the presence of different promoters or a positive regulatory molecule such as the E1a protein.
Abortion as a stigma: In the eyes of the beholder

Abstract The purpose of this study was to investigate social perceptions of a man who impregnated a woman and advised her to have an abortion, and those of a woman who had an abortion. Each subject rated one of four persons on a social distance measure: either a man involved in an abortion, a woman having had an abortion, a male control target, or a female control target. Both abortion targets were perceived less favorably than the control targets. The female abortion target was rejected more by male subjects than by female subjects, and the male abortion target was more rejected by females than by males. While holding permissive attitudes toward abortion was related to willingness to meet the female abortion target, restrictive attitudes toward abortion predicted willingness to meet the male abortion target. Variables related to stigmatization of the man were lack of identification, restrictive attitudes toward abortion, and perceived responsibility. Restrictive attitudes toward women's rights and roles in this society and restrictive attitudes toward abortion predicted stigmatization of the woman. It is suggested that shifting one's attention from characteristics of the stigmatized to observers' characteristics provides a useful perspective on the stigmatization process.
Deciphering the role of docosahexaenoic acid in brain maturation and pathology with magnetic resonance imaging

Animal studies have found that deficits in brain docosahexaenoic acid (DHA, 22:6n-3) accrual during perinatal development leads to transient and enduring abnormalities in brain development and function. Determining the relevance of this evidence to brain disorders in humans has been hampered by an inability to determine antimortem brain DHA levels and limitations associated with a postmortem approach. Accordingly, there is a need for alternate or complementary approaches to better understand the role of DHA in cortical function and pathology, and conventional magnetic resonance imaging (MRI) techniques may be ideally suited for this application. A major advantage of neuroimaging is that it permits prospective evaluation of the effects of manipulating DHA status on both clinical and neuroimaging variables. Emerging evidence from MRI studies suggest that greater DHA status is associated with cortical structural and functional integrity, and suggest that reduced DHA status and abnormalities in cortical function observed in psychiatric disorders may be interrelated phenomenon. Preliminary evidence from animal MRI studies support a critical role of DHA in normal brain development. Neuroimaging research in both human and animals therefore holds tremendous promise for developing a better understanding of the role of DHA status in cortical function, as well as for elucidating the impact of DHA deficiency on neuropathological processes implicated in the etiology and progression of neurodevelopmental and psychiatric disorders.
THE EQUITY EFFECTS OF STATE SCHOOL FINANCE REFORMS: A METHODOLOGICAL CRITIQUE AND NEW EVIDENCE

Since 1970, over half the states have reformed their school finance systems with improvement in equity of revenue and resource distributions as one of the stated goals. While numerous studies evaluating the equity effects of these often expensive reforms have been undertaken, there remains much disagreement about how to assess the reforms' impacts. In this article, we address the problems of measuring equity effects with an emphasis on the need for multiple definitions and an understanding of the value judgments inherent in all measures of equity. Next, three methodologies that have been used to assess the equity impacts of school finance reform are critiqued. Finally, in an effort to correct shortcomings of each, a fourth methodology is developed and new empirical evidence on the effects of reform based on that methodology are presented. The article concludes with observations about the importance of the choice of a methodology with which to evaluate complex policy changes that involve value judgments about what is fair, just, and equitable.
Dream reports and the test of emotional styles: A convergent ‐ discriminant validity study

Thirty-eight undergraduates completed the forced-choice form of the Test of Emotional Styles and participated in a 4-day dream recall study. Correlational analysis was performed with the three dimensions of emotional style and two dream report aspects as variables. The dimensions failed to correlate significantly with any of the dream report variables, although the dimensions intercorrelated significantly among themselves. Doubt is expressed as to the construct validity of the subscales of the Test of Emotional Styles.
Pluto's climate modeled with new observational constraints

Abstract Pluto has a nitrogen atmosphere in vapor pressure equilibrium with surface ice. N 2 is mobile and is transported seasonally even at Pluto’s cold temperatures in the outer Solar System. A thermal model developed by Hansen and Paige in 1996 to model Pluto’s climate has been re-deployed in response to new data and in anticipation of the New Horizons flyby of Pluto in 2015. A number of stellar occultations have been observed in the last 11 years as Pluto has crossed the galactic plane. New Hubble Space Telescope images show a variegated surface. These recent observations allow us to model Pluto’s climate with much tighter constraints. Our findings suggest that Pluto’s atmosphere will not collapse prior to the arrival of New Horizons although pressure will be dropping as N 2 condenses on the south polar cap. This finding is in contrast to the Olkin et al. (Olkin et al. [2013]. arXiv1309.0841O) prediction that permanent volatiles in the northern hemisphere maintain Pluto’s atmospheric pressure throughout its orbit. The range of surface pressures predicted for 2015 for nine cases with very good matches to observables is 0.3–3.2 Pa. The best match predicts that New Horizons will detect an atmospheric pressure of 2.4 Pa.
Polygenic Control of Drosophila Morphogenesis During the Stages of Determination and Specification of Adult Structures

There are three processes in the development of Drosophila which may be studied independendy but which are a manifestation of interdependent events which result in the formation of the adult phenotype. These processes are determination, specification and differentiation. The mutant phenotype Abnormal-abdomen is characterized by a loss of abdominal tergites and is controlled by a major mutant gene, A53g and a polygenic modifier system. The development of the abnormal phenotype is influenced by events in early embryogenesis and in mid-larval stages. These developmentally sensitive stages are correlated with the periods of determination and specification of the cells which constitute the larval histoblast nests and which differentiate into the adult abdominal hypoderm. Evidence for gene control at these two development stages are 1) a maternal effect of the genome correlated with changes in the efficiency of enzymes catalyzing tRNA aminoacylating reactions, 2) observations which relate histological defects of embryos at the blastoderm stage to the action of the mutant genotype, and 3) a temperature sensitive period for the expression of the abnormal phenotype which has defined limits in the late second and early third larval instars. Developmental events which take place during oogenesis, early embryogenesis, and mid-larval stages are discussed with regard to their relationship to each other and to the final differentiation of the adult phenotype.
On global stability in distributed parameter systems

Abstract A mehtod is presented for determining finite stability regions for distributed parameter systems whose transient behavior is governed by a single parabolic differential equation. The case of an adiabatic catalytic reaction is discussed in detail. However, the same techniques can be applied to many other systems in which chemical reactions and diffusions are coupled. The method is based on the maximum principle for parabolic partial differential equations. It is shown that finite regions of stability can be determined immediately from the knowledge of the steady state profiles, without having to perform any additional computations. A discussion is included of the case in which the transient behavior is governed by two coupled partial differential equations.
GABAA α1 and α2 receptor subunit expression in rostral ventrolateral medulla in nonpregnant and pregnant rats

Abstract Pregnancy results in attenuated baroreflex mediated sympathoexcitatory responses which may be due to potentiation of γ-aminobutyric acid (GABA) inhibition in the rostral ventrolateral medulla (RVLM). The major metabolite of progesterone, 3α-hydroxy-dihydroprogesterone (3α-OH-DHP), which is elevated in pregnancy, is a potent neurosteroid positive modulator of GABA A receptors, and sensitivity of GABA A receptors to 3α-OH-DHP is dependent on the receptor subunit composition. The purpose of this study was to evaluate the GABA A α 1 and α 2 receptor subunit mRNA and protein expression in the RVLM of nonpregnant and late term pregnant rats. Micropunches of RVLM were collected from nonpregnant and late term pregnant rats and the expression levels of GABA A α 1 and α 2 receptor subunits were analyzed using quantitative competitive reverse transcriptase polymerase chain reaction (RT-PCR) and immunoblot techniques. The competitive RT-PCR analysis allows comparison of expression levels between different mRNA, and the mRNA expression level of GABA A α 1 was several hundred fold greater than GABA A α 2 in both groups. However, this relative distribution of GABA A α 1 and α 2 receptor subunits protein or mRNA expression was not altered in late term pregnant compared to nonpregnant rats. These data demonstrate, that within the RVLM of both nonpregnant and late term pregnant rats, the relative expression levels of GABA A α 1,2 receptor subunits favor GABA A receptors susceptible to positive modulation by progesterone metabolites.
Minimum wages and school enrollment of teenagers: a look at the 1990's

Abstract Interest in the effects of the minimum wage on teenagers’ school enrollment has grown in recent years. This issue is of increasing importance given recent calls for increasing the minimum wage. Some authors argue that higher minimum wages will hurt teenagers by lowering their school enrollment. In this paper we estimate the effects of higher minimum wages on school enrollment using the Common Core of Data, collected by the US Department of Education. These data cover the entire population of public school students in the United States. Controlling for local labor market conditions and state and year fixed effects we find some evidence that higher minimum wages reduce teen school enrollment in states where students can drop out before the age of 18. This appears to be driven by the grade 9 to grade 10 transition. We find no effects for higher-grade levels or in states where students cannot drop out until they are 18. This suggests that minimum wages may have a substantial effect on teens’ schooling effort in these early grades but also that these unintended effects can be offset by policies that encourage continued school enrollment.
Characterization of the induction of increased thermotolerance by high osmolarity inSalmonella

Factors limiting the growth ofSalmonellaat high temperature were analyzed in minimal medium. The growth ofS. typhimuriumwas curtailed at 44°C by high temperature-dependent block in methionine synthesis. At 45°C, the organism could not grow in glucose-mini- mal medium even with methionine, but growth could be restored at this temperature by the addition of NaCl in the final concentration range of 0.15–0.3m. Similar results were obtained with twoS. enteritidisstrains. The growth stimulatory effect of high osmolarity at 45°C was not altered by the osmoprotectant compound glycine betaine. Exposure to 0.3mNaCl also increased the resistance ofS. typhimuriumto thermal death at 50°C and to the oxidizing agent H2O2. However, the high osmolarity-dependent induction of enhanced resistance to 50°C and to H2O2was completely abolished by glycine betaine. The finding that glycine betaine blocks the induction of resistance to lethal high temperature by high osmolarity could provide a means for enhancing the bactericidal efficacy of heating, because it may be possible to increase the heat sensitivity of contaminating bacteria by supplementing food products with this naturally occurring plant metabolite, prior to thermal processing.
LacZ gene transfer to skeletal muscle using a replication-defective herpes simplex virus type 1 mutant vector.

ABSTRACT Herpes simplex virus type 1 (HSV-1) represents a promising new viral vector capable of efficient transduction of myofibers in vivo. Here we report on the use of a replication-defective HSV-1 mutant vector (DZ) deleted for the essential immediate early (IE) gene ICP4 for studies of reporter gene transfer and expression following direct inoculation of mouse skeletal muscle. The recombinant vector was engineered to contain the Escherichia coli lacZ gene under transcriptional control of the strong human cytomegalovirus (HCMV) IE promoter. The effect of vector cytotoxicity on the durability of transgene expression following infection of muscle cells in culture and myofibers in vivo revealed that this first-generation HSV vector was cytopathic, limiting the persistence of vector-transduced cells. UV irradiation of vector preparations reduced viral cytotoxicity for myoblasts in culture without reducing significantly β-galactosidase production. Moreover, muscle cell viability and the durability of transg...
Extended boundedness concept for the problem of Lur'e

The Lur'e problem is extended to systems in which the nonlinear function violates the sector condition for both small and large values of its argument. A suitable definition of a region of boundedness is made, and estimates of this region are found by means of the quadratic Lyapunov function, whose existence is guaranteed by satisfaction of a Popov condition.
Choline's phosphorylation in rat striatal slices is regulated by the activity of cholinergic neurons

The mechanism by which populations of brain cells regulate the flux of choline (Ch) into membrane or neurotransmitter biosynthesis was investigated using electrically stimulated superfused slices of rat corpus striatum. [Me-14C]Ch placed in the superfusion medium for 30 min during a 1-h stimulation period was incorporated into tissue [14C] phosphorylcholine (PCh) and [14C]phosphatidylcholine (PtdCh). Stimulation also caused a profound inhibition of PCh synthesis and a 10-fold increase in [14C]ACh release into the medium; it failed to affect tissue [14C]ACh levels. This effect was not explained by changes in ATP levels nor in the kinetic properties of Ch kinase (E.C. 2.7.1.32) or Ch acetyltransferase (ChAT) (E.C.2.3.1.7). To investigate the mechanism of these effects, Ch uptake studies were performed with and without hemicholinium-3 (HC3), a selective inhibitor of high affinity Ch uptake. A two-compartment model accurately fit the observed data and yielded a K(m) for Ch uptake of 5 microM into cholinergic structures and 72 microM into all other cells. Using this model it was estimated that cholinergic neurons account for 60% of observed uptake of Ch at physiologic Ch concentrations, even though they represent fewer than 1% of the total cells in the slice. The model also predicts that an increase in Ch uptake within cholinergic neurons, reported to be associated with depolarization [4,27,32], would significantly inhibit Ch uptake into all other cells, and would account for the observed decrease in PCh synthesis.
A noisy teenager

A 13 year old boy was referred for evaluation of his troublesome asthma symptoms. He had a six month history of episodic acute dyspnoea on minimal exertion—for example, climbing stairs. Between episodes he could exercise maximally without difficulty. Dyspnoea was accompanied by a loud inspiratory noise, described as “wheeze” but not cough. The episodes occurred only at school, lasted for five to 10 minutes, and resolved completely. He was diagnosed with asthma when he was 2 years old because of nocturnal cough, and he had been treated with inhaled steroids until recently. His father reported that his son’s pulse raced in the morning. On examination he was well. His height and weight both lay on the 75th centile. He had no stigmata of chronic lung disease, such as fingernail clubbing or chest wall deformity. He had a hoarse voice. The results of chest radiography and pulmonary function testing were normal. Electrocardiography showed a sinus tachycardia of 120 beats per minute. A diagnosis of vocal cord dysfunction was made and the boy was referred for speech therapy. One month later he developed nausea and vomiting, and was noted …
Fostering outdoor learning experiences with urban youth through place-based expeditionary learning

This paper is a conceptual discussion informed by practice, which offers a model of Place-Based Expeditionary Learning (PBEL) appropriate for integrating outdoor and experiential learning experiences into urban classrooms. The discussion examines issues related to the accessibility of outdoor experiential education programs, defines PBE and EL, and demonstrates the need for urban youth to develop a sense of place. The PBEL model is intended to be useful as a tool for individual educators in a variety of settings and contexts by providing a conceptual framework for integrating outdoor and experiential learning experiences through cultural and nature studies. Possible applications of such a model and suggestions for further research are offered.
Electron Spin Resonance and Electron Spin Echo Modulation Studies of Ion-Exchanged NiH−SAPO-17 and NiH−SAPO-35 Molecular Sieves: Comparison with Ion-Exchanged NiH−SAPO-34 Molecular Sieve

Erionite-like silicoaluminophosphate molecular sieve SAPO-17 and levyne-like SAPO-35, in which Ni ions were incorporated via solid-state ion-exchange into known extraframework sites, have been studied by electron spin resonance (ESR) and electron spin echo modulation (ESEM). The Ni ion reducibility, location, and interaction with several adsorbates have been investigated. Among these adsorbates, the interaction with nitric oxide was emphasized and compared to that of Ni ion with NO in the previously studied chabazite-like SAPO-34. Room-temperature adsorption of C2D4 on NiH−SAPO-17 after dehydration at 573 K, oxygen treatment at 823 K, evacuation, and subsequent hydrogen treatment at 573 K produces two Ni−ethylene complexes. Carbon monoxide adsorption gives rise to a Ni(I)−(CO)n complex with unresolved 13C hyperfine lines. Following the kinetics of nitric oxide adsorption on NiH−SAPO-17 shows that initially, a Ni(I)−(NO)+ complex, a NO radical, and a new species which appears to be another NO species are g...
Recurrent Guillain-Barré syndrome following influenza vaccine

Two patients recovered from an attack of Guillain-Barre syndrome and then had a second attack of this disease, with a shorter latent period, following monovalent influenza vaccination. These cases suggest that an attack of Guillain-Barre syndrome may result in greater risk of future episodes of the syndrome in conjunction with exposure to influenza or other vaccinations.
Are combined CT scans of the thorax being overused

Purpose A news article in June 2011 reported that Medicare claims showed considerable overuse of "double" CT scans of the thorax (ie, combined scans without contrast followed by with contrast) at a number of hospitals. Most radiologists agree that they should be done only on rare occasions. The aim of this study was to determine what proportion of all thoracic CT scans are combined scans in the Medicare population. Methods The data sources were the Medicare Part B Physician/Supplier Procedure Summary Master Files for 2001 to 2011. The 3 Current Procedural Terminology codes for thoracic CT (with contrast, without contrast, and without plus with contrast) were selected. Utilization rates per 1,000 beneficiaries and the percentage that were combined scans were calculated. Results The utilization rate of combined scans increased from 2001 through 2006, remained steady in 2007, but then decreased sharply thereafter. The compound annual rate of change from 2007 to 2011 was −10.4%. From 2001 through 2006, combined thoracic CT scans constituted 6.0% to 6.1% of all thoracic CT scans. However, from 2006 to 2011, this percentage progressively declined, reaching a low of 4.2% in 2011. Conclusions Despite the 2011 news report, only a very small percentage of thoracic CT scans nationwide are done both without and with contrast. Moreover, that percentage dropped by almost one-third from 2006 to 2011, suggesting that the practice is declining. The figure of 4.2% can be used as a benchmark against which to judge radiology facilities in the future.
Conjunctive bias in memory representations of logical connectivesa

The paper presents the conjunctive bias in memory—a novel phenomenon that helps to clarify representations of logical connectives. The conjunctive bias is a tendency toward more accurate recall and recognition of conjunctive forms than of forms based on other logical connectives and a tendency to recall and recognize other logical forms as if they were conjunctions. Three experiments, in which participants’ memory representations associated with different logical connectives were examined, were conducted to test the conjunctive bias hypothesis. In Experiment 1, participants learned picture-proposition pairs involving either conjunctions or disjunctions and then had to recall each proposition when cued with its picture. In Experiments 2 and 3, recognition memory for conjunctions, disjunctions, and conditionals was examined with an old/new recognition procedure. The findings of these experiments provide evidence for the conjunctive bias. Furthermore, the results of Experiment 3 suggest that conjunctive bias is not simply a pragmatically caused preference for conjunctions. The discussion focuses on the implications of these findings for current theories of deductive reasoning.
Using glutamate homeostasis as a target for treating addictive disorders

Well-developed cellular mechanisms exist to preserve glutamate homeostasis and regulate extrasynaptic glutamate levels. Accumulating evidence indicates that disruptions in glutamate homeostasis are associated with addictive disorders. The disruptions in glutamate concentrations observed after prolonged exposure to drugs of abuse are associated with changes in the function and activity of several key components within the homeostatic control mechanism, including the cystine/glutamate exchanger xc(-) and the glial glutamate transporter, EAAT2/GLT-1. Changes in the balance between synaptic and extrasynaptic glutamate levels in turn influence signaling through presynaptic and postsynaptic glutamate receptors, and thus affect synaptic plasticity and circuit-level activity. In this review, we describe the evidence for impaired glutamate homeostasis as a critical mediator of long-term drug-seeking behaviors, how chronic neuroadaptations in xc(-) and the glutamate transporter, GLT-1, mediate a disruption in glutamate homeostasis, and how targeting these components restores glutamate levels and inhibits drug-seeking behaviors.
Estimation of recruitment rates and survival from field census data with application to poikilotherm populations

A procedure is developed for estimating population recruitment rates based upon field census data of mixed ages of the population. Such estimation is necessary when sampling newly recruited individuals is much more difficult than the sampling of more mature members of the population. The method utilizes a population dynamics model in conjunction with least squares estimation. A procedure for poikilotherm organisms is used to estimate oviposition and survival rates of Hypera postica.
Sodium channel blockers and axonal protection in neuroinflammatory disease.

Although demyelination is a cardinal feature of neuroinflammatory conditions such as Guillain–Barre syndrome (GBS) and multiple sclerosis, axonal degeneration also occurs in these disorders. Because loss of axons causes permanent, non-remitting loss of neurological function, there is substantial interest in protection of axons in these situations. Protection of axons within white matter and peripheral nerves, however, is likely to require strategies different from those that might be expected to be protective in grey matter of the nervous system; the higher surface-to-volume ratio and different complement of molecules that are expressed in axons compared with neuronal cell bodies imply that the molecular mechanisms underlying axonal degeneration are different from those that cause neurons to die. Studies over the past decade have demonstrated that a sustained sodium influx through voltage-gated sodium channels can trigger reverse sodium–calcium exchange which imports damaging levels of calcium into axons after they are exposed to insults such as anoxia, thereby activating injurious calcium-mediated processes (Stys et al ., 1992 a ). Persistent sodium currents have, in fact, been demonstrated along the trunks of axons within the CNS (Stys et al ., 1993) and PNS (Tokuno et al ., 2003), and sodium channel blockers have been shown to have a protective effect, preventing axonal degeneration when axons are exposed to anoxia (Stys et al ., 1992 b ). A link to …
Addressing Trauma and Psychosocial Development in Juvenile Justice-Involved Youth: A Synthesis of the Developmental Neuroscience, Juvenile Justice and Trauma Literature

Youth incarcerated in the juvenile justice system are disproportionately exposed to traumas both in and outside of custody that are associated with poor social, behavioral, and developmental outcomes. The purpose of this paper is to describe one pathway through which trauma can impact a myriad of outcomes, including delinquency, violence, substance use, and other behaviors that are self-regulatory in nature. Relevant research from the developmental neuroscience, juvenile justice, and trauma literatures are drawn upon and synthesized to describe this pathway. Using a multi-disciplinary approach to understanding the role that brain development and neural activity play in the relationship between trauma and associated behavioral outcomes could serve to inform juvenile justice policy decisions and intervention practice. Such application could increase the effectiveness with which juvenile justice systems work with one of the most vulnerable and traumatized populations of youth in today’s society: those incarcerated in our juvenile justice system.
Two new species of Miconia sect. Sagraea (Melastomataceae) from the Macaya Biosphere Reserve, Haiti, and twelve relevant new species combinations

The Sagraea clade (Melastomataceae, tribe Miconieae) is briefly characterized, typified, and formally treated as a section within Miconia. In addition, two new species of Miconia sect. Sagraea, endemic to the floristically diverse Massif de la Hotte of southwestern Haiti and discovered during the course of a systematic revision of the Caribbean species of this section, are here described and illustrated. Miconia hottensis and M. navifolia, morphologically similar and possible sister species, are compared to each other and to the widespread Caribbean species M. capillaris and the southwestern Dominican Republic endemic M. tetraptera; these four species share rectangular stems with four low ridges or wings and minute, short-stalked, peltate or pseudopeltate hairs and likely form a clade.
Cellular targets and trophic functions of neurotrophin-3 in the developing rat hippocampus.

Abstract The expression of the neurotrophins and trk receptors in the hippocampus has directed attention toward their roles in the development and maintenance of this region. We have examined the effects of the neurotrophins NT-3, BDNF, and NGF in cultures of developing rat hippocmpal cells by two criteria: rapid induction of c- fos and neurotrophic responses. The selective induction of c- fos mRNA suggests the presence of functional receptors for NT-3 and BDNF, but not NGF, in embryonic hippocampal cultures. The NT-3-responsive cells were localized in pyramidal neurons of areas CAI through CA3 and dentate granular and hilar cells of postnatal organotypic slices, as detected by c-Fos immunocytochemistry. In addition to immediate early responses, NT-3 caused a 10-fold increase in the number of cells expressing the neuronal antigen calbindin-D 28k . This increase was dose dependent, with maximal stimulation at 10 ng/ml. In contrast, BDNF elicited small but significant calbindin responses. These results indicate biological responses to NT-3 in the CNS and suggest roles for for this neurotrophin during hippocampal neurogenesis.
Neurobehavioral effects from acute exposures to methyl isobutyl ketone and methyl ethyl ketone.

Abstract Subjects were tested for neurobehavioral performance in an environmental chamber to detect the presence of subclinical central nervous system effects from 4-hr exposures to methyl isobutyl ketone (MIBK) at 100 ppm, methyl ethyl ketone (MEK) at 200 ppm, MIBK at 50 ppm with MEK at 100 ppm, or a placebo (i.e., a 5-min presentation of 25 ppm MEK-MIBK at each exposure period outset). Subjects were 68 males and 75 females recruited from local universities; ages ranged from 18 to 32 years. Ethanol by ingestion (95% – 0.84 ml/kg) was used as a positive control. Five psychomotor tests (choice reaction time [CRT], simple reaction time [SRT], visual vigilance, dual task [auditory tone discrimination and tracking], memory scanning), one sensorimotor test (postural sway), and a test of mood (profile of mood states) were used to measure neurobehavioral effects. Additionally, chemical measurements (blood and breath) and reports of sensory andirritant effects were measured. The chemical exposures produced statistically significant performance effects on only 4 of 32 measures (% correct responsesvisual vigilance, movement time-CRT, SRT, % incorrect responses-dual task). These effects, however, were not substantial and could not be attributed directly to the chemical exposures. Alcohol ingestion, however, produced significant decrements on every performance test except memory scanning and mood. An interaction occurred between gender and alcohol ingestion, such that more statistically significant performance decrements were found for females than for males. Significant odor sensations and irritant effects were reported by the subjects during the chemical exposures. The MEK results agree with earlier MEK experiments at comparable exposure conditions, and the MIBK results are consistent with a recent Swedish study that used MIBK exposures and showed no significant behavioral performance decrements from single MIBK exposures at 50 ppm with 50 W exercise. Additionally, the MIBK-MEK combination exposure showed no evidence of any interaction effects on either the behavioral or chemical measurements. The principal effects resulting from exposures to MEK and MIBK at the durations and concentrations used in the study are limited to sensory and irritant effects.