cssi/SciSciGPT-SciSciNet huggingface dataset:
The effects of pH on the growth of Chlorella vulgaris and its interactions with cadmium toxicity.

The effects of pH alone, and in combination with exposure to 0.89 μM cadmium, on the growth response of the green algaChlorella vulgaris were evaluated. Acidic (3.0–6.2) and alkaline (8.3–9.0) pH values retarded the growth of this alga. Optimal growth occurred when the pH of the medium was adjusted to values of 7.5 and 8.0. When the cells were exposed to pH adjusted medium plus the presence of 0.89 μM Cd, a value known to reduce population growth by 50% at the control pH of 6.9, the affects were additive at the acidic (3.0–5.0) pH ranges. At alkaline pH values of 8.3–9.0 all toxicity responses could be explained by pH adjustment alone, indicating that additional cadmium toxicity was absent. At pH values of 7.5 and 8.0, cadmium toxicity was mitigated against, and resultant growth at pH 8.0 was at the same enhanced rate as this pH without cadmium.
Gender distinctions and lateral asymmetry in the low-level auditory brainstem response of the human neonate

Threshold measures of auditory brainstem response (ABR) were generated in 72 full-term newborn infants in response to clicks and tone burst stimuli between 500 and 8000 Hz as detailed in a previous study. These results were further analyzed for differences in response related to ear (lateral asymmetry) and subject gender. Thresholds obtained in male infants were significantly lower than those of females (P = 0.0485). The greatest differences in threshold between male and female infants occurs in the right ear (7.45 dB) as opposed to the left ear (1.56 dB). Both male and female infants have significantly larger wave V amplitude elicited from the right ear than the left (P = 0.0002) using low-level stimuli. Also, as has been noted in adults, female infants have larger amplitude ABRs than males (P = 0.0018), but amplitude differences across gender are significant only in the right ear (ear by gender interaction P = 0.0278). Results of this study indicate that gender differences and lateral asymmetry in auditory function are not a result of gender bias for or unbalanced auditory trauma, but a biologically significant phenomenon that is present at birth. The argument is made that superior right ear performance may be part of cerebral laterality in auditory function.
In vitro preparation and characterization of a 700 nm absorbing chlorophyll-water adduct according to the proposed primary molecular unit in photosynthesis.

Abstract 1. This study characterizes chlorophyll a -H 2 O adducts in vitro in order to establish their generic relationship to the recently proposed [15, 18–20, 31] primary molecular adduct in photosynthesis. The effects of water titration and temperature on the absorption, fluorescence, excitation, and redox properties of the various in vitro chlorophyll a aggregate species are investigated. 2. From fluorescence measurements, we conclude that the driest chlorophyll a sample contains an equimolar amount of water. This conclusion is consistent with earlier experimental work [2, 3, 14, 17, 31], and clarifies the origin of the controversial [15] Katz model [14] of chlorophyll a -H 2 O interactions. 3. With increasing water concentration or as the temperature is lowered below room temperature, the A -663 monohydrate chlorophyll a · H 2 O (species absorbing at 663 nm) is favored at the expense of the A -678 anhydrous aggregate according to the equilibrium 2H 2 O + chlorophyll a 2 ai 2 chlorophyll a · H 2 O. Under excess water conditions, A -663 is converted to A -743 (chlorophyll a · 2H 2 O) n . 4. On slow sample cooling to T ⪅ 200 °K, we observe the growth of A -700 at the expense of A -663. There is a direct correspondence between the increasing (decreasing) absorption by A -700 ( A -663) and increasing (decreasing) fluorescence at 720 nm (664 nm). 5. It is concluded that A -700 is most probably the dimer participating in the equilibrium 2 chlorophyll a · H 2 O ai (chlorophyll a · H 2 O) 2 . The A -700 band consists of two exciton components (separated by ≈ 280 cm −1 ) that are interpretable in terms of the dimeric origin of A -700. 6. The deconvoluted A -700 absorption spectrum and the excitation spectrum of the 720 nm fluorescence are compared with the light-minus-dark spectra of P -700. 7. It is found that A -700 is reversibly bleached by I 2 ( E 0 = 0.54 V). The significance of this observation is discussed in terms of the redox properties of monomeric chlorophyll a and P -700.
Improved survival with screening for hepatocellular carcinoma

Hepatocellular cancer (HCC) is a frequent cause of cancer death worldwide. Although successful screening programs exist in Asian countries, the role for screening in the United States is not dear. The purpose of this study is to determine if screening has an effect on survival in a predominantly Asian population in Hawaii. We retrospectively reviewed cases of HCC from 1993 to 1998 for demographic data, risk factors, symptoms, stage, treatment, and survival. Patients were divided into 3 groups according to presentation: symptomatic (S), asymptomatic (A), and asymptomatic but screened for disease (A/Sc). Kaplan-Meier analysis was performed on overall survival by group. Ninety-one patients were referred for HCC. There were 56 patients in group S, 19 patients in group A, and 16 patients in group A/Sc. Patients in group A/Sc survived significantly longer than those in group S (P = .009), with the former group having a median survival of 1,399 versus 234 days for group S. Median survival for group A was 545 days and did not differ significantly from the other groups. Patients who are asymptomatic and screened for HCC have an increased survival compared with those patients who present with symptoms. This may justify the use of a formal screening program for HCC in Hawaii, but we would need to investigate this prospectively.
keV particle bombardment of semiconductors: A molecular-dynamics simulation.

Molecular-dynamics simulations have been performed for the keV particle bombardment of Si{110} and Si{100} using a many-body potential developed by Tersoff. Energy and angle distributions are presented along with an analysis of the important ejection mechanisms. We have developed a computer logic that only integrates the equations of motion of the atoms that are struck, thus decreasing the computer time by a factor of 3 from a complete molecular-dynamics simulation.
Spontaneous nickel monosilicide nanowire formation by metal induced growth

Abstract Nickel monosilicide (NiSi) nanowires (NWs) were grown at a relatively low temperature of 575 °C by the Metal Induced Growth (MIG) method without using a gas type silicon source. In the MIG technique, silicon dioxide is first plasma deposited onto a Si wafer followed by 20–160 nm of Ni. Si is then deposited by D.C. magnetron sputtering on the heated substrate. A nickel silicide is first formed which then leads to nanowire formation. Nanowires were a single crystal structure, 20–100 nm in diameter and 1–10 μm in length. Composition and structure were verified by high-resolution transmission electron microscopy (HRTEM) and Raman spectroscopy. The mechanism of NiSi nanowire formation is discussed herein.
UNION ORGANIZATION IN ADVANCED INDUSTRIAL DEMOCRACIES

I suggest a new explanation of cross-national differences in unionization rates: the size of the labor force. Size matters because the gains unions are able to achieve in collective bargaining depend on the proportion of substitutable workers who are organized, while the costs of organizing depend in part on the absolute number to be recruited. The comparison of the costs and benefits of organizing new workers yields the conclusion that unions in larger labor markets will accept lower levels of unionization. Statistical analysis of cross-national differences in unionization rates among advanced industrial societies in the late 1970s indicates that the size of the labor force and the cumulative participation of leftist parties in government explain most of the variance.
Role Of Torsional Dynamics In The Photophysics Of Xanthene Dyes

ABSTRACT Fluorescence lifetime data for rhodamine B in a series of normal alcohols have been measured as a function of-temperature, solvent polarity, and viscosity. Nonradiative rates for internal conversion have been extracted from this data. The solvent dependence of the nonradiative rates is discussed in terms of two activated barrier crossing models. In one model the activation energy is a linear function of the solvent polarity parameter Eip(30). In another model, the solvent dependence of the nonradiative rate is taken into account by a viscosity (dependent pre-exponential factor. Consistent results are obtained when a polarity-dependent activation energy is used. 1. INTRODUCTION Solvent effects are important in determining the photophysical properties of dye molecules in solution. The fluorescence lifetime of rhodamine B is very sensitive to the nature of the solvent in which the dye is dissolved. This has been attributed to the rotation of the diethylamino groups on the xanthene ring:1Electron delocalization causes the xanthene ring and amino groups to be coplanar in the ground state. In the excited state the bond order of the CN bond decreases, lowering the torsional barrier. Examination of steric effects in molecular models shows that the twisted state is likely to be a stable configuration. When these groups are immobilized in the planar configuration as in rhodamine 101, the fluorescence quantum yield is found to be virtually unity.1"3The photophysics of rhodamine B can be analyzed in terms of the photophysicalkpttpSOmechanism, where k^ is the radiative rate constant, kpt is the rate constant for rotation about the CN bond from the planar conformation at 9p to the twisted conformation at 6t along the S^ potential energy surface, ktp is the rate constant for rotation about the CN bond from the twisted back to the planar conformation along the S± potential energy surface, and k^c is the internal conversion rate constant in twisted configuration. The set of processes above provides a mechanism by which torsional motion can induce internal conversion. Internal conversion from the planar form at 0p is not important, because such a process would give rise to a finite nonradiative decay path at low temperatures, with a fluorescence quantum yield of less than unity, contrary to what has been experimentally found.2"3 If rotation about the CN bond is the rate-limiting step in this mechanism, the nonradiative rate knr will be equal to kpt.
Scream: A new code for solar cell degradation prediction using the displacement damage dose approach

based executable code has been developed called SCREAM (Solar Cell Radiation Environment Analysis Models) which implements the displacement damage dose (DDD) approach to solar cell degradation prediction in a space radiation environment.
Molecular cloning of a complementary deoxyribonucleic acid encoding the thyrotropin-releasing hormone receptor and regulation of its messenger ribonucleic acid in rat GH cells

Rat pituitary GH cells have been used extensively to study the biochemical actions of TRH on lactotropic cells. To investigate the structure and regulation of the rat TRH receptor (rTRHR), we have cloned its cDNA from GH4C1 cells. Using the polymerase chain reaction with degenerate primers and pools of cloned cDNAs from a GH4C1 cDNA library, a fragment sharing high similarity to the mouse thyrotrope TRHR (mTRHR) was identified. Conventional library screening with this fragment was used to isolate a single cDNA. mRNA synthesized in vitro from this cDNA was injected into Xenopus oocytes, and a characteristic conductance response to TRH was detected by voltage clamp recording. DNA sequence analysis revealed a molecule of 412 amino acid residues, with 96% similarity to the mTRHR. However, in contrast to the mTRHR, the rTRHR had an additional 19 amino acid residues at its carboxy-terminus. A mRNA of about 4 kilobases was identified in GH3 cells. Regulation of the rTRHR mRNA concentration was studied in GH3 cells. Steady state rTRHR mRNA levels were decreased to 30% of the control level by incubation with TRH for 48 h and increased 4-fold by incubation with dexamethasone for 12 h. Southern blot analysis of genomic DNA from GH3 cells gave a simple banding pattern consistent with a single copy gene. We conclude that the rTRHR shares high primary sequence similarity to the mTRHR, but the rTRHR has an extension of 19 amino acids at its carboxy-terminus, which is lacking in the mTRHR.
Writing Scale Development and Use Within a Language Program

Developing assessments within a program can create more useful measures of our students' language. This includes rating scales used in performance assessments such as writing or speaking tests. This article describes the process of development, use, and revision of a writing placement scale by teachers in an intensive English language program. To develop the scale, writing from students in the program was examined by instructors to create a data-driven scale. After piloting, the scale underwent years of use and continued study. This sustained investigation of the scale led to revisions, but also to confidence and program fit. Following the narrative of the scale reveals a process for programs to develop and evaluate measures locally with teacher involvement.
Impact of Managerial Power on Persuasive Strategy Selection by Female and Male Managers

This article compares and contrasts the persuasive communication of male and female middle managers, focusing on the mediating influence of a manager's power on his or her selection of anticipated ...
Police minority recruitment: A note on its effectiveness in improving black evaluations of the police

Abstract This research note explores the relationship between police minority recruitment and black attitudes toward the police. Two specific measures of the independent variable—minority recruitment—were examined. In spite of considerable speculation to the contrary, neither program variable was found to have the expected effect on minority attitudes. This held for a variety of dependent variables. Several suggestions about the results are offered and discussed.
Studying links via closed braids IV: composite links and split links

The main result concerns changing an arbitrary closed braid representative of a split or composite link to one which is obviously recognizable as being split or composite. Exchange moves are introduced; they change the conjugacy class of a closed braid without changing its link type or its braid index. A closed braid representative of a composite (respectively split) link is composite (split) if there is a 2-sphere which realizes the connected sum decomposition (splitting) and meets the braid axis in 2 points. It is proved that exchange moves are the only obstruction to representing composite or split links by composite or split closed braids. A special version of these theorems holds for 3 and 4 braids, answering a question of H. Morton. As an immediate Corollary, it follows that braid index is additive (resp. additive minus 1) under disjoint union (resp. connected sum).
Paley-Wiener subspace of vectors in a Hilbert space with applications to integral transforms

Article history: The goal of this article is to introduce an analogue of the Paley-Wiener space of bandlimited functions, PWω, in Hilbert spaces and then apply the general result to more specific examples. Guided by the role that the differentiation operator plays in some of the characterizations of the Paley-Wiener space, we construct a space of vectors using a self- adjoint operator D in a Hilbert space H, and denote this space by PWω(D) .T he article can be virtually divided into two parts. In the first part we show that the space PWω(D) has similar properties to those of the space PWω, including an analogue of the Bernstein inequality and the Riesz interpolation formula. We also develop a new characterization of the abstract Paley-Wiener space in terms of solutions of Cauchy problems associated with abstract Schrodinger equations. Finally, we prove two sampling theorems for vectors in PWω(D), one of which uses the notion of Hilbert frames and the other is based on the notion of variational splines in H. In the second part of the paper we apply our abstract results to integral transforms associated with singular Sturm-Liouville problems. In particular we obtain two new sampling formulas related to one-dimensional Schrodinger
Practical Methods for Solid-State NMR Distance Measurements on Large Biomolecules: Constant-Time Rotational Resonance

Simple modifications of the rotational resonance experiment substantially reduce the total experimental time needed to measure weak homonuclear dipolar couplings, a critical factor for achieving routine internuclear distance measurements in large biomolecular systems. These modifications also address several problems cited in the literature. Here we introduce a constant-time rotational resonance experiment that eliminates the need for control spectra to correct for effects from variable RF heating, particularly critical for accurate long-distance measurements. This reduces the total number of experiments needed by as much as a factor of 2. Other improvements incorporated include achieving selective inversion with a delay rather than a weak pulse (P. R. Costa et al., J. Am. Chem. Soc. 119, 10487-10493, 1997), which we observe results in the elimination of oscillations in peak intensities for short mixing time points. This reduces the total experiment time in two ways. First, there is no longer a need to average different "zero"-time points (S. O. Smith et al., Biochemistry 33, 6334-6341, 1994) to correct for intensity variations. Second, short-mixing-time lineshape differences observed in large membrane-bound proteins only appear with the weak-pulse inversion and not when using the delay inversion. Consistent lineshapes between short and long mixing times permit the use of a single spectrum for subtraction of natural abundance background signals from all labeled-protein time points. Elimination of these effects improves the accuracy and efficiency of rotational resonance internuclear distance measurements.
A new approach to production equilibria in vector lattices

Abstract We prove the existence of a competitive quasi-equilibrium in a production economy in which the commodity space is a vector lattice endowed with a topology, but is not necessarily a topological vector lattice. The key assumption necessary to prove the existence theorem is that both preferences and production sets are proper as defined by Mas-Colell (1986a, b). We show that the definition of proper production can be weakened significantly in the case where the commodity space is a topological vector lattice.
EFFECT OF THYROID HORMONE TREATMENT ON THYROMEGALY IN CHILDREN AND ADOLESCENTS WITH HASHIMOTO'S THYROIDITIS

The effectiveness of thyroxine treatment in childhood to reduce thyromegaly in Hashimoto's thyroiditis is controversial. Previous data are based on responses of both adults and children, and thyroid function is frequently not well documented. The present study was undertaken to determine whether certain subgroups of children with goitrous Hashimoto's disease might more readily show a reduction in the size of their thyroid glands when treated with thyroid hormone. Sixty-nine patients ≤ 18 years of age evaluated since 1982 with antibody proven Hashimoto's disease and more than minimally enlarged thyroid glands were identified. All patients were followed for ≥ 1 year and examined by palpation at least twice in the 12 month period after diagnosis. Only clearly identifiable changes in thyroid gland size were used to categorize patients. Thirteen of 50 patients treated with thyroxine were euthyroid prior to therapy; in no case did treatment affect gland size. A different response (p < 0.001) was observed in the 21 hypothyroid children: 16 (76%) had a reduction of their gland size while only in 5 (24%) patients thyromegaly persisted without change. Of 16 treated patients with compensated hypothyroidism (mean TSH 16.4 ± 3.9 mU/L), 12 (75%) showed no change and 4 (25%) a reduction. Variable courses independent of TSH levels were observed in the 19 untreated patients: smaller in 5 (26%), unchanged in 10 (53%) and larger in 4 (21%). We conclude that only hypothyroid children with Hashimoto's disease respond to thyroxine treatment with a reduction of thyromegaly (in 76% of cases), whereas no significant benefit of treatment could be shown in patients with normal plasma thyroxine levels prior to therapy regardless of TSH levels.
A Rediscovered Alliance: Can New Music Performance Teaching Policy Save Music Education? A New Framework for the Music Studio

Music education in K–12 school programs may continue to lose ground to other subjects unless music education and performance studies are viewed as interdependent. The author argues that the reinvigoration of both music education and performance requires that the studio experience integrate a research-based pedagogy, multi-stylistic range of repertoire, and improvisation studies.
A New Method for Credit-Enhancement Standards

A new approach, based on corporate bond default data, is proposed to determine the quantity of new equity capital a bond issuer must consistently raise (or the amount of current debt it must retire) to enhance its bond ratings. The current approach of the rating industry to determine such standards for upgrading bond ratings assumes that the probability of bond default by the issuer is unaffected by the new equity capital or retiring of debt. The specification in the new approach relaxes this assumption. The estimates show dramatically different standards for bond-rating upgrades between the approach suggested here and the standard industry approach.
Protein-mediated selenium biomethylation in evaporation pond water

Selenium (Se) is a contaminant of agricultural drainage water in the San Joaquin Valley, California and the cause of major toxicity problems among the wildlife. The objective of this study was to investigate the stimulatory properties of proteins and their components with respect to biological Se dissipation. Laboratory studies showed that Se biomethylation is protein-peptidelimited rather than nitrogen-, amino acid- or carbon-limited. Crude casein and its components, ∂-, β-, and κ-caseins and peptides (1 g carbon [C] L−1 pond water) were equally stimulatory producing a >50-fold enhancement in dimethylselenide (DMSe) yield. Dephosphorylation of casein resulted in a 57% reduction in Se volatilization. Dialysis studies indicated that the active ingredient of casein is likely to be a peptide or peptide mixture. Casein did not appear to increase Se methylation through any physicochemical characteristics such as a change in pH or chelation of pond water ions. Alternative protein sources including cottonseed meal, cheese whey and yeast sludge dramatically increased methylation (29-fold, 300-fold and 41-fold, respectively) over unamended samples, with over 10% of the Se inventory converted into DMSe in 17 d. A single casein amendment (0.2 g CL−1) to water columns in the field caused a 38% Se loss from the initial inventory of a San Joaquin Valley evaporation pond in 142 d. Under optimum conditions, protein-mediated deseleinfication of agricultural drainage water is a promising and novel bioremediation technique to permanently remove Se on site.
Limits to ‘The Learning Region’: What University-centered Economic Development Can (and Cannot) do to Create Knowledge-based Regional Economies:

Proponents of the learning region assert that investments should be made in the infrastructure that supports regionally-located innovative firms and that both institutional and governmental resources should be directed to drive the success of the regional innovation system. In this paper, we look at critical limitations to the realization of the learning region and at potential conflicts arising from the relative power of private and public interests in determining the learning region agenda. We draw on examples from Europe and the US, but pay special attention to the US case where the divide between regional economic development goals and the incentives driving the research university are particularly dramatic.
Eine Synthese der Anomeren des 4.6‐Benzal‐methyl‐D‐glucosaminids über Derivate des N‐Formyl‐D‐glucosamins

Die Synthese der genannten Anomeren erfolgte durch Benzylidierung und Glykosidierung des N-Formyl-D-glucosamins und alkalische Hydrolyse der N-Formyl-Gruppe.
Abnormal chloride conductance in multidrug resistant HL60/AR cells.

Chloride channel currents were measured in drug sensitive parental HL60 and multidrug resistant (MDR) subline HL60AR cells, using a whole cell patch-clamp technique. In addition, the in vitro effects of 4,4′ diisothiocyana-tostilbene-2,2′-disulfonic acid (DIDS), a Cl− channel blocker, on intracellular accumulation and sensitivity to daunorubicin and intracellular pH (pHi) in HL60 cells were examined. Baseline DIDS blockable Cl− currents were consistently lower in HL60AR cells (0.9 pA/pF) as compared to HL60 cells (7.0 pA/pF). Similarly cAMP-activated Cl− currents were minimal in HL60AR cells (0.2 pA/pF) as compared to HL60 cells (8 pA/pF). In vitro treatment of drug sensitive HL60 cells with DIDS resulted in concentration-dependent decreased accumulation and increased resistance to daunorubicin and decreased pHi. These data show that altered Cl− permeability is associated with MDR and suggest that Cl− channels may play a role in MDR.
Analysis of a graph coloring based distributed load balancing algorithm

Abstract We present the analysis of a distributed load balancing algorithm based on edge coloring of undirected graphs. One version (linear version) can be studied directly using linear system theory. We show that the performance of another version (integer version), which is more realistic in that the loads are integers, can be studied as a perturbation of the linear version. Both versions of our algorithm converge to stable behavior for arbitrary topologies. In the case of the binary n -cube processor network we prove that after n steps of the integer version, for any initial load distribution, each processor has a load not more than n /2 away from the average.
Chemical Vapor Deposition in the Boron‐Carbon‐Nitrogen System

The preparation of a two-phase coating of B4C-BN was addressed as a potential wear coating because of its likelihood of having a high fracture toughness resulting from its composite nature and inherent lubrication due to the presence of BN. Equilibrium analysis identified appropriate deposition conditions; however, deposited coatings were found to be single-phase BN with a high degree of substitution of carbon for nitrogen.
Global Cognitive Factors Modulate Correlated Response Variability between V4 Neurons

Recent studies have shown that cognitive factors such as spatial and feature-based attention, learning, and task-switching can change the extent to which the trial-to-trial variability in the responses of neurons in sensory cortex is shared between pairs of neurons (for review, see Cohen and Kohn, 2011). Global cognitive factors related to concentration, motivation, effort, arousal, or alertness also affect performance on perceptual tasks and the responses of individual neurons in many cortical areas (Spitzer et al., 1988; Spitzer and Richmond, 1991; Motter, 1993; Bichot et al., 2001; Hasegawa et al., 2004; Boudreau et al., 2006; Niwa et al., 2012). The question of how global cognitive factors affect correlated response variability is important because these factors likely vary both across and within all psychophysical and physiological studies. Furthermore, global cognitive factors might provide a convenient platform for studying the neuronal mechanisms underlying how cognitive factors affect correlated variability because they can be manipulated easily without training complex perceptual tasks. We recorded simultaneously from groups of neurons in visual area V4 while rhesus monkeys performed a contrast discrimination task whose difficulty changed in blocks of trials. We found that correlated variability decreased when the task was more difficult, even when the visual stimuli were far outside the receptive fields of the recorded neurons. Our results suggest that studying global cognitive factors might provide a general framework for studying how cognitive factors affect the responses of neurons throughout sensory cortex.
Defective cholinergic innervation in pyloric muscle of patients with hypertrophic pyloric stenosis

The etiology of hypertrophic pyloric stenosis (HPS) is not known. Many investigators have studied the myenteric plexus and muscle in HPS, but there are no reports of cholinergic nerve distribution in this condition. A histochemical technique for the detection of acetylcholinesterase (AChE) has been used to study cholinergic nerve distribution. Recently, it has been shown that the development and survival of cholinergic neurons in the peripheral and central nervous system depend on the presence of nerve growth factor (NGF) and its receptor (NGFR). We examined pyloric muscle from 18 patients with HPS and 10 controls using monoclonal antibody to NGFR and AChE histochemistry. Myenteric plexus displayed strong NGFR and AChE reactivity. Quantitative assessment of immunoreactivity in nerve fibres within pyloric muscle demonstrated selective absence of NGFR and AChE-positive nerve fibres in the circular and longitudinal muscle of HPS, whereas these fibres were in abundance in the muscle of controls. These findings suggest that NGFR is an important neurotrophic factor in the maintenance of cholinergic neuronal function and that NGFR deficiency, resulting in defective cholinergic innervation of pyloric muscle, may have an important role in the pathogenesis of HPS.
Activation of serotonin1A receptors inhibits midbrain periaqueductal gray neurons of the rat

Abstract The midbrain periaqueductal gray (PAG) is involved in a variety of functions including pain modulation, vocalization, autonomic control, fear and anxiety. This area contains serotonin receptors, particularl 5-HT 1A that are known to play a role in the above functions The goals of this study were to characterize the effects of 8-OH-DPAT, a selective 5-HT 1A agonist, on the firing characteristics and membrane properties of PAG neurons. Both in vivo and in vitro preparations were used. The effects of 8-OH-DPAT on baseline activity of 91 neurons were tested in the in vivo preparation. In 50/91 cells, 8-OH-DPAT produced a decrease in the firing rate that ranged between 21 and 98% (mean±S.E.M. decrease of49±1.9%). This inhibitory effect was dose dependent and could be blocked by spiperone. In 10/91 cells, 8-OH-DPAT produced an increase in the firing rate that range between 13 and 290%, with mean increase of83±7.4%. The baseline fate of the remaining 31 cells was not affected by 8-OH-DPAT. In the PAG slice preparation, the effects of 8-OH-DPAT on synaptic and membrane properties of 17 PAG neurons were tested using whole-cell voltage clamp-recording procedures. In 14 cells, application of 8-OH-DPAT produced hyperpolarization that ranged between 6 and 21 mV, with mean of8.4±2.0mV. This hyperpolarization was associated with a decrease in membrane impedance that ranged between 8 and 45%, with mean decrease of21.6±4.5%. The remaining three neurons did not respond to 8-OH-DPAT. Under voltage clamp conditions and in the presence of TTX, application of 8-OH-DPAT produced a reversal potential that ranged between −70 and −90 mV, with mean of−80±2.68mV. In conclusion: (1) 8-OH-DPAT has a strong influence on neurons in all regions of the PAG in particular on cells located in the dorsal PAG; (2) in both in vivo and in vitro preparations, the 5-HT 1A -mediated response of PAG neurons in inhibitory; and (3) the inhibitory effect of 5-HT 1A is associated with hyperpolarization of the cell membrane that is likely due to an increase in K conductance.
Activation of lecithin : cholesterol acyltransferase by apolipoproteins E-2, E-3, and A-IV isolated from human plasma

Apolipoprotein A-IV, apolipoprotein E-2 and apolipoprotein E-3 were individually incorporated into defined phosphatidylcholine/cholesterol liposomes for study of lecithin:cholesterol acyltransferase activation. Enzyme activities obtained with these liposomes were compared with that from liposomes containing purified apolipoprotein A-I. Apolipoprotein A-IV, apolipoprotein E-2, and apolipoprotein E-3 all activated lecithin:cholesterol acyltransferase. With purified enzyme and with egg yolk phosphatidylcholine as the acyl donor, maximal activation was obtained at a concentration of approximately 0.5 nmol for apolipoprotein A-IV and 0.4 nmol for the apolipoprotein E isoforms. Apolipoprotein A-IV was approximately 25% as efficient as apolipoprotein A-I for the activation of purified enzyme; apolipoprotein E-2 was 40% as efficient, and apolipoprotein E-3, 30%. Similar activation results were obtained using plasma as the enzyme source. Analysis of the plasma of patients with absence of apolipoprotein A-I or with only trace amounts of apolipoprotein A-I exhibited a reduced rate of cholesterol esterification and lecithin:cholesterol acyltransferase activity that was proportional to the reduced level of the enzyme's mass. These results indicate that apolipoprotein A-IV and apolipoprotein E may serve as physiological cofactors for the enzyme reaction.
The Physical Education Teacher Education Faculty Shortage

(2006). The Physical Education Teacher Education Faculty Shortage. Journal of Physical Education, Recreation & Dance: Vol. 77, No. 3, pp. 3-56.
Mast cells are required for angiogenesis and macroscopic expansion of Myc-induced pancreatic islet tumors

An association between inflammation and cancer has long been recognized, but the cause and effect relationship linking the two remains unclear. Myc is a pleiotropic transcription factor that is overexpressed in many human cancers and instructs many extracellular aspects of the tumor tissue phenotype, including remodeling of tumor stroma and angiogenesis. Here we show in a beta-cell tumor model that activation of Myc in vivo triggers rapid recruitment of mast cells to the tumor site-a recruitment that is absolutely required for macroscopic tumor expansion. In addition, treatment of established beta-cell tumors with a mast cell inhibitor rapidly triggers hypoxia and cell death of tumor and endothelial cells. Inhibitors of mast cell function may therefore prove therapeutically useful in restraining expansion and survival of pancreatic and other cancers.
Impact of metabotropic glutamate 2/3 receptor stimulation on activated dopamine release and locomotion.

Rationale Activation of metabotropic glutamate (mGlu) 2/3 receptors may provide a novel strategy for treating schizophrenia. This effect is thought to be mediated through dopamine-independent mechanisms because mGlu2/3-receptor agonists have no considerable affinity for dopamine receptors. These agonists, however, reduce amphetamine-induced hyperlocomotion suggesting that they influence dopamine neurotransmission.
Rigid cyclic group actions on cohomology complex projective spaces

In this paper we discuss smooth and locally smooth cyclic actions on cohomology complex projective spaces. We shall show that in low dimensions the presence of a codimension-two fixed-point component forces many algebraic invariants to behave as they do in the linear examples.
Modeling decision-making in single- and multi-modal medical images

This research introduces a mode-specific model of visual saliency that can be used to highlight likely lesion locations and potential errors (false positives and false negatives) in single-mode PET and MRI images and multi-modal fused PET/MRI images. Fused-modality digital images are a relatively recent technological improvement in medical imaging; therefore, a novel component of this research is to characterize the perceptual response to these fused images. Three different fusion techniques were compared to single-mode displays in terms of observer error rates using synthetic human brain images generated from an anthropomorphic phantom. An eye-tracking experiment was performed with naive (non-radiologist) observers who viewed the single- and multi-modal images. The eye-tracking data allowed the errors to be classified into four categories: false positives, search errors (false negatives never fixated), recognition errors (false negatives fixated less than 350 milliseconds), and decision errors (false negatives fixated greater than 350 milliseconds). A saliency model consisting of a set of differentially weighted low-level feature maps is derived from the known error and ground truth locations extracted from a subset of the test images for each modality. The saliency model shows that lesion and error locations attract visual attention according to low-level image features such as color, luminance, and texture.
The Role of Stress Arousal in the Dynamics of the Stressor‐to‐Illness Process among Accountants*

. This study investigates the Kahn et al. (1964) measure of job-related stressors, and the Everly et al. (1989) measure of stress (i.e., cognitive-affective) arousal to ascertain whether the scales are measuring two distinct constructs. Data gathered from a sample of 1,618 members of the American Institute of Certified Public Accountants are analyzed to measure the psychometric properties of both instruments. Results from internal consistency, exploratory and confirmatory factor analyses, and item analyses indicate that both scales are reliable measures and the two scales are measuring different constructs, This study also examines the mediating effect of stress arousal on the relationship between sources of job stress, and resultant coping behaviors and psychological stress symptoms by means of structural modeling analyses. The results indicate that stress arousal is indeed a significant mediator in the stressor-to-illness process. Resume. Les auteurs analysent l'instrument de mesure utilise par Kahn et al. (1964) pour evaluer les facteurs de stress lies au travail ainsi que la mesure de la manifestation (cognitive-affective) du stress proposee par Everly et al. (1989) pour confirmer si les echelles utilisees circonscrivent deux concepts distincts. Ils analysent les donnees colligees a partir d'un echantillon de 1 618 membres de l'American Institute of Certified Public Accountants afin d'evaluer les proprietes psychometriques des deux instruments de mesure. Les resultats tires des analyses des facteurs de coherence interne, des facteurs exploratoires et des facteurs de corroboration, ainsi que les analyses des elements indiquent que les deux echelles de mesure sont fiables et qu'elles circonscrivent des concepts differents. Les auteurs examinent egalement l'effet de mediation de la manifestation du stress sur la relation entre les sources de stress au travail et les comportements d'adaptation qui en resultent et les symptomes de stress psychologique, au moyen d'analyses de modelisation des structures. Les resultats de l'etude indiquent que la manifestation du stress est, de fait, un mediateur d'importance dans le processus qui conduit du facteur de stress a la maladie.
Elemental Subsets: The Building Blocks of Regression

Abstract In a regression dataset an elemental subset consists of the minimum number of cases required to estimate the unknown parameters of a regression model. The resulting elemental regression provides an exact fit to the cases in the elemental subset. Early methods of regression estimation were based on combining the results of elemental regressions. This approach was abandoned because of its computational infeasibility in all but the smallest datasets and because of the arrival of the least squares method. With the computing power available today, there has been renewed interest in making use of the elemental regressions for model fitting and diagnostic purposes. In this paper we consider the elemental subsets and their associated elemental regressions as useful “building blocks” for the estimation of regression models. Many existing estimators can be expressed in terms of the elemental regressions. We introduce a new classification of regression estimators that generalizes a characterization of ordin...
Bladder Dysfunction and Altered Somatic Sensitivity in PACAP−/− Mice

Purpose: PACAP and receptors are expressed in micturition pathways. Studies show that PACAP has a role in detrusor smooth muscle contraction to facilitate adenosine triphosphate release from urothelium and PACAP antagonism decreases cyclophosphamide induced bladder hyperreflexia.Materials and Methods: PACAP contributions to micturition and somatic sensation were studied in PACAP knockout (PACAP−/−), litter mate heterozygote (PACAP+/−) and WT mice by conscious cystometry with continuous intravesical saline or acetic acid (0.5%) instillation, urination patterns, somatic sensitivity testing of hind paw and pelvic regions with calibrated von Frey filaments, and morphological bladder assessments.Results: PACAP−/− mice had an increased bladder mass with fewer but larger urine spots. In PACAP−/− mice the lamina propria and detrusor smooth muscle were significantly thicker but the urothelium was unchanged. PACAP−/− mice had increased bladder capacity, voided volume and intercontraction interval with significantly...
Controllability, coping behavior, and stress-induced analgesia in the rat.

Abstract Exposure to painful or stressful stimuli produces an analgesic reaction which can persist for 1–2 h post-stress. In the typical stress-induced analgesia study the subject is not permitted to alter or exert control over the aversive event to which it is exposed. That is, its behavior affects neither the duration or intensity of the event. The experiments reported here attempted to determine whether this inability of the subject to control the aversive event is an important determinant of stress-induced analgesia, or whether simple exposure to painful events is a sufficient condition for its production. In the first experiment rats were given either escapable electric shocks (the subject's behavior could terminate the shock), equal amounts of inescapable shock, or no shock. Tail-flick to radiant heat was assessed 30 min later. The group given inescapable shock was strongly analgesic, while the group given an equal amount of escapable shock was only mildly analgesic. Thus the controllability of the shock or the availability of a coping response determined the antinociceptive reaction which followed. The second experiment revealed that this differential effect of controllability on tail-flick responding is masked, shortly after the end of the shock session, by a transient analgesic effect of shock which is not sensitive to the controllability dimension. The implications of these results for stress-induced analgesia and the activation of opioid systems are discussed.
Regulating incentives: the past and present role of the state in health care systems

The desire of national policymakers to encourage entrepreneurial behavior in the health sector has generated not only a new structure of market-oriented incentives, but also a new regulatory role for the State. To ensure that entrepreneurial behavior will be directed toward achieving planned market objectives, the State must shift modalities from staid bureaucratic models of command-and-control to more sensitive and sophisticated systems of oversight and supervision. Available evidence suggests that this structural transformation is currently occurring in several Northern European countries. Successful implementation of that shift will require a new, intensive, and expensive strategy for human resources development, raising questions about the financial feasibility of this incentives-plus-regulation model for less-well-off CEE/CIS and developing countries.
Growth Responses of Avena Stem Segments to Various Sugars

THE internodal extension which occurs in stems of grasses with onset of reproductive phase is a remarkably striking morphogenetic process1, the causal basis for which has not been elucidated. We have been attacking this problem from several points of view, one of which is to culture excised stem segments on various substrates to assay by quantitative means the intercalary growth that occurs in internode portions of these segments. We wish to report here on the growth responses of Avena segments to a variety of sugars. It is quite possible that several of these may be directly implicated in intercalary growth of internodes of this plant in vivo.
Technology: Photonics illuminates the future of radar

The first implementation of a fully photonics-based coherent radar system shows how photonic methods for radio-frequency signal generation and measurement may facilitate the development of software-defined radar systems. See Letter p.341 The next generation of radar systems will need to be highly automated and use software-defined signal generation and detection for flexible operation in surveillance and wireless communication applications. However, the necessary analogue-to-digital conversion poses serious technical limits for conventional microwave electronic components. That makes photonic radar an attractive option, well suited to digital operation. Until now photonics-based generation and detection of radio signals have generally been studied separately. Here Paolo Ghelfi et al. combine the individual components to produce a functioning, complete photonic radar system. The system's effectiveness and precision are demonstrated in a field trial involving the detection of passing aircraft.
Floating-point to fixed-point conversion with decision errors due to quantization

Most existing analyses of quantization effects are given under the condition that all decision-making blocks, if they exist in a system, produce identical decisions in both fixed-point and infinite-precision (IP) implementations. However, in doing floating-point to fixed-point conversion (FFC), a fixed-point design with occasional decision errors may still be an acceptable approximation of the IP system. We study the effect of this decision error, and relate its probability to the fixed-point data types. Our previous FFC methodology is then extended to include systems with possible decision errors due to quantization. The extended approach is applied to both CORDIC and a BPSK transceiver.
Edge detection in optical flow fields

Optical flow is potentially valuable as a source of spatial information. Current techniques provide flow fields which are noisy and sparse, making the recovery of spatial properties difficult at best. This paper describes a technique for locating discontinuities in optical flow, which typically correspond to object boundaries. A simple blurring interpolator is used to smooth out noise and produce denser fields. Discontinuities are found by locating the vector field equivalent of zero crossings in the Laplacian of a scalar field. The technique is illustrated by applying it to realistic vector fields which are both noisy and sparse.
Forming a three dimensional environment model using multiple observations

An autonomous navigating agent must form a three-dimensional model of its environment using passive sensors. Typical stereo algorithms produce sparse depth maps and cannot be used to distinguish between holes and solid objects in the environment. The authors present a novel methodology for creating a three-dimensional model of the environment. They divide the environment into a set of disjoint cells. Using multiple images obtained from different view points, they estimate the mean and variance of intensity observed for each cell. The computed variance can be used to distinguish between empty and full cells in the environment. The technique, unlike the typical stereo methodology, does not rely on solving the correspondence problem. The resulting model of the environment is dense and can be used directly for navigation. Experimental results are presented. >