cssi/SciSciGPT-SciSciNet huggingface dataset:
A disorganized innervation of the inner ear persists in the absence of ErbB2

ErbB2 protein is essential for the development of Schwann cells and for the normal fiber growth and myelin formation of peripheral nerves. We have investigated the fate of the otocyst-derived inner ear sensory neurons in the absence of ErbB2 using ErbB2 null mutants. Afferent innervation of the ear sensory epithelia shows numerous fibers overshooting the organ of Corti, followed by a reduction of those fibers in near term embryos. This suggests that mature Schwann cells do not play a role in targeting or maintaining the inner ear innervation. Comparable to the overshooting of nerve fibers, sensory neurons migrate beyond their normal locations into unusual positions in the modiolus. They may miss a stop signal provided by the Schwann cells that are absent as revealed with detailed histology. Reduction of overshooting afferents may be enhanced by a reduction of the neurotrophin Ntf3 transcript to about 25% of wild type. Ntf3 transcript reductions are comparable to an adult model that uses a dominant negative form of ErbB4 expressed in the supporting cells and Schwann cells of the organ of Corti. ErbB2 null mice retain afferents to inner hair cells possibly because of the prominent expression of the neurotrophin Bdnf in developing hair cells. Despite the normal presence of Bdnf transcript, afferent fibers are disoriented near the organ of Corti. Efferent fibers do not form an intraganglionic spiral bundle in the absence of spiral ganglia and appear reduced and disorganized. This suggests that either ErbB2 mediated alterations in sensory neurons or the absence of Schwann cells affects efferent fiber growth to the organ of Corti.
Virtual electrode theory explains pacing threshold increase caused by cardiac tissue damage

The virtual electrode polarization (VEP) effect is believed to play a key role in electrical stimulation of heart muscle. However, under certain conditions, including clinically, its existence and ...
Strongyloides spp.: Demonstration and partial characterization of acidic collagenolytic activity from infective larvae

Infective larvae of Strongyloides spp. have been shown to contain azocollytic enzymes which may aid in host skin penetration. Attempts to demonstrate classical, neutral pH-active collagenase activity in Strongyloides ratti were unsuccessful. In the current study, we investigated the presence of acidic collagenolytic activity in the infective larvae of Strongyloides ransomi, S. ratti, and S. stercoralis. All three species demonstrated collagenolytic activity in acidic homogenates as well as in neutral freeze-thaw fractions. Biochemical characterization of this collagenolytic activity from S. ratti and S. ransomi indicated that it was active over an acidic pH range, although it was stable at a neutral pH. This, along with molecular weight estimates and inhibitor susceptibilities, suggested that the collagenolytic activity was similar to vertebrate acidic cysteinyl proteinases. These studies also indicated that this activity is similar to the acidic cysteinyl proteinases in extracts of S. ransomi.
An attenuated total reflection study of silver film growth

Abstract We have used the Kretschmann configuration of the attenuated total reflection (ATR) technique to observe surface plasmons in thin evaporated silver films. An abrupt transition in the ATR was observed at a substrate temperature near 50 °C. When the substrate was held at temperatures below 50 °C during deposition, a sharp, well-defined plasmon was obtained. The silver film is thus indicated to be smooth and continuous. For substrate temperatures above 54 °C, the ATR curve had a broad minimum extending over most angles above the critical angle. This indicates silver to be discontinuous when deposited at higher temperatures. Although film structure is heavily dependent on parameters such as deposition rate, substrate temperature and gas pressure, this abrupt transition in such a narrow temperature range came as a surprise.
The Tactile Movement Aftereffect

The existence of a tactile movement aftereffect was established in a series of experiments on the palmar surface of the hand and fingers of psychophysical observers. During adaptation, observers cupped their hand around a moving drum for up to 3 min; following this period of stimulation, they typically reported an aftereffect consisting of movement sensations located on and deep to the skin, and lasting for up to 1 min. Preliminary experiments comparing a number of stimulus materials mounted on the drum demonstrated that a surface approximating a low-spatial-frequency square wave, with a smooth microtexture, was especially effective at inducing the aftereffect; this adapting stimulus was therefore used throughout the two main experiments. In Experiment 1, the vividness of the aftereffect produced by 2 min of adaptation was determined under three test conditions: with the hand (1) remaining on the now stationary drum; (2) in contact with a soft, textured surface; or (3) suspended in air. Subjects' free magnitude estimates of the peak vividness of the aftereffect were not significantly different across conditions; each subject experienced the aftereffect at least once under each condition. Thus the tactile movement aftereffect does not seem to depend critically on the ponditions of stimulation that obtain while it is being experienced. In Experiment 2, the vividness and duration of the aftereffect were measured as a function of the duration of the adapting stimulus. Both measures increased steadily over the range of durations explored (30-180 sec). In its dependence on adapting duration, the aftereffect resembles the waterfall illusion in vision. An explanation for the tactile movement aftereffect is proposed, based on the model of cortical dynamics of Whitsel et al. (1989, 1991). With assumed modest variation of one parameter across individuals, this application of the model is able to account both for the data of the majority of subjects, who experienced the aftereffect as opposite in direction to the adapting stimulus, and for those of an anomalous subject, who consistently experienced the aftereffect as being in the same direction as the adapting stimulus.
The Ability of Deaf and Hearing Children to Apply Morphological Rules

A paper and pencil test, devised to assess knowledge of morphological rules, was administered to 140 deaf students, aged 7 to 19, and to 176 hearing students, aged 7 to 18. Although the hearing sub...
Bringing statistical mechanics into chemistry: The early scientific work of Karl F. Herzfeld

The physicist Karl F. Herzfeld was instrumental in introducing the techniques of statistical mechanics to physical chemists in the years between 1920 and 1935. Herzfeld's work included an early derivation of the rate constant for a first order reaction. This was similar to and fifteen years earlier than Eyring's calculation of the rate constant. Herzfeld also carried out the first calculation of a relaxation equation for vibrational energy transfer. Herzfeld's success lay in his classical approach to physics, which, it is suggested, made his work accessible to chemists.
Low-Energy Chlorophyll States in the CP43 Antenna Protein Complex: Simulation of Various Optical Spectra. II

The CP43 protein complex of the core antenna of higher plant photosystem II (PSII) has two quasidegenerate "red" absorption states. It has been shown in the accompanying paper I (Dang, N. C., et al. J. Phys. Chem. B 2008, 112, 9921.) that the site distribution functions (SDFs) of red-states A and B are uncorrelated and the narrow holes are burned in subpopulations of chlorophylls (Chls) from states A and B that are the lowest-energy pigments in their particular CP43 complexes and cannot further transfer energy downhill. In this work, we present the results of a series of Monte Carlo simulations using the 3.0-A structure of the PSII core complex from cyanobacteria (Loll, B., et al. Nature 2005, 303, 1040.) to model absorption, emission, persistent, and transient hole burned (HB) spectra. At the current structural resolution, we found calculated site energies (obtained from INDO/S calculations) to be only suggestive because their values are different for the two monomers of CP43 in the PS II dimer. As a result, to probe the excitonic structure, a simple fitting procedure was employed to optimize Chl site energies from various starting values corresponding to different A/B pigment combinations to provide simultaneously good fits to several types of optical spectra. It is demonstrated that the shape of the calculated absorption, emission, and transient/persistent hole-burned spectra is consistent with experimental data and our model for excitation energy transfer between two quasi-degenerate lowest-E states (A and B) with uncorrelated SDFs discussed in paper I. Calculations revealed that absorption changes observed near 670 nm in the non-line-narrowed persistent HB spectra (assigned to photoconversion involving Chl-protein hydrogen-bonding by Hughes (Biochemistry 2006, 45, 12345.) are most likely the result of nonphotochemical hole-burning (NPHB) accompanied by the redistribution of oscillator strength due to modified excitonic interactions. We argue that a unique redistribution of oscillator strength during the NPHB process helps to assign Chls contributing to the low-energy states. It is demonstrated that the 4.2 K asymmetric triplet-bottleneck (transient) hole is mostly contributed to by both A and B states, with the hole profile described by a subensemble of pigments, which are the lowest-energy pigments (B s- and A s-type) in their complexes. The same lowest-energy Chls contribute to the observed fluorescence spectra. On the basis of our excitonic calculations, the best Chl candidates that contribute to the low-energy A and B states are Chl 44 and Chl 37, respectively.
Spin-State Effects on the Thermal Dihydrogen Release from Solid-State [MH(η2-H2)dppe2]+ (M = Fe, Ru, Os) Organometallic Complexes for Hydrogen Storage Applications.

Mossbauer spectroscopy, experimental thermodynamic measurements, and computational studies were performed to investigate the properties of molecular hydrogen binding to the organometallic fragments [MHdppe2]+ (M = Fe, Ru, Os; dppe =1,2-bis(diphenylphosphino)ethane) to form the dihydrogen complex fragments [MH(η2-H2)dppe2]+. Mossbauer spectroscopy showed that the dehydrogenated complex [FeHdppe2]+ adopts a geometry consistent with the triplet spin state, transitioning to a singlet state complex upon addition of the dihydrogen molecule in a manner similar to the previously studied dinitrogen complexes. From simulations, this spin transition behavior was found to be responsible for the strong binding behavior experimentally observed in the iron complex. Spin-singlet to spin-singlet transitions were found to exhibit thermodynamics consistent with the 5d > 3d > 4d binding trend observed for other transition metal dihydrogen complexes. Finally, the method for distinguishing between dihydrogen and dihydride comp...
Deformation behavior of hot dip galvanized coatings in complex sheet metal forming

The hot dipped galvanized coatings of flexible tubes with variable corrosion resistances were examined by x-ray diffraction and scanning electron microscopy (SEM). Accelerated corrosion was related to wide cracks formed during roll forming of coatings with coarse spangle sizes and preferred orientation of Zn basal planes parallel to the coating surface. Coarse spangled coatings with reduced preferred orientation of basal planes parallel to sheet surfaces formed only thin cracks and accommodated forming strain primarily by plastic flow. Coatings with fine spangle sizes and preferred parallel basal plane orientations developed networks of fine cracks during forming. The zinc coatings with fine cracks did not expose sufficient steel to cause accelerated galvanic corrosion.
Stability analysis of a predictor/multi-corrector method for staggered-grid Lagrangian shock hydrodynamics

This article presents the complete von Neumann stability analysis of a predictor/multi-corrector scheme derived from an implicit mid-point time integrator often used in shock hydrodynamics computations in combination with staggered spatial discretizations. It is shown that only even iterates of the method yield stable computations, while the odd iterates are, in the most general case, unconditionally unstable. These findings are confirmed by, and illustrated with, a number of numerical computations. Dispersion error analysis is also presented.
IN VIVO EFFECTS OF β-CAROTENE ON ACTIVATED NEUTROPHILS

Patients with gram negative sepsis may suffer neutropenia and respiratory distress associated with activation of polymorphonuclear neutrophils (PMN). Infusion with the synthetic analog of the bacterial chemoattractant N-Formyl-Methionyl-Leucyl-Phenylalanine (FMLP) causes a dramatic but transient neutropenia, hypotension and respiratory distress in rabbits. Employing this rabbit model, we have shown previously that pretreatment with vitamin E (vit E) accelerates the return of the absolute granulocyte count (AGC) and mean blood pressure (MBP) toward normal at 10 min but not at 5 min after FMLP infusion. To test the effects of another antioxidant β-carotene (BC) on neutrophil activation in vivo we pretreated rabbits with BC to raise plasma levels (test 1.1±.8ug/ml vs control .05±.06ug/ml p=0.02). When 0.5ug FMLP was administered iv AGC decreased (at 2.5 min % change was 34±1.3 control vs 25±10 test p=ns). By 5 min there was a significantly greater return of PMN to the peripheral circulation in the BC treated animals (% change 39.6± vs 61±5 controls p < 0.04). There was not a significant difference in % change of MBP between test and control animals at any time over the 30 minutes of monitoring. Thus, BC appears to be more effective than vit E in accelerating the return of PMN to the peripheral circulation following activation and may have therapeutic potential in diseases associated with PMN activation.
Synoptic Parameters as Discriminators between Hailfall and Less Significant Convective Activity in Northeast Colorado

Abstract Synoptic data are studied to determine which, if any, parameters representing large-scale physical processes can be used to discriminate effectively between days of insignificant convective activity and those with significant moist convection and high hail potential in northeast Colorado. Divergence, relative vorticity, vorticity advection, temperature advection, surface mixing ratio and a modified K index (George, 1960) were computed and associated with observed weather. Two methods were used to compare distributions of these parameters for their discriminative potential. The first involved ranking of the Student's t statistics for both hail versus no-hail and significant versus insignificant convection stratifications. The second method was a graphical technique for plotting cumulative relative frequencies of the stratified distributions. The most effective parameter on a comparative basis for discriminating between significant and insignificant convection was a measure of low-level and middle-...
Water-soluble cytochromes from a blue-green alga. I. Extraction, purification, and spectral properties of cytochromes C (549, 552, and 554, Anacystis nidulans)

Abstract 1. Three water-soluble cytochromes were isolated from the blue-green alga, Anacystis nidulans, by an aqueous extraction of lyophilized cells, the most satisfactory technique of the several tried. Separation of the cytochromes was accomplished on a DEAE-cellullose column and 2 of the cytochromes were highly purified using (NH4)2SO4 fractionation and further column chromatography. 2. The absorption spectra of the most highly purified samples of all 3 cytochromes resemble those of c- type cytochromes with α bands at 549, 552, and 554 mμ. 3. Cytochrome C (549) appears anomalous in its unusually low α peak at 549 mμ, and in being very autoxidizable. 4. The stability of cytochromes C (549 and 554) towards heat, and alkaline and acid pH is described.
Consumer return chronology alters recovery trajectory of stream ecosystem structure and function following drought

Consumers are increasingly being recognized as important drivers of ecological succession, yet it is still hard to predict the nature and direction of consumer effects in nonequilibrium environments. We used stream consumer exclosures and large outdoor mesocosms to study the impact of macroconsumers (i.e., fish and crayfish) on recovery of intermittent prairie streams after drying. In the stream, macroconsumers altered system recovery trajectory by decreasing algal and macroinvertebrate biomass, primary productivity, and benthic nutrient uptake rates. However, macroconsumer influence was transient, and differences between exclosures and controls disappeared after 35 days. Introducing and removing macroconsumers after 28 days resulted mainly in changes to macroinvertebrates. In mesocosms, a dominant consumer (the grazing minnow Phoxinus erythrogaster) reduced macroinvertebrate biomass but had little effect on algal assemblage structure and ecosystem rates during recovery. The weak effect of P. erythrogaster in mesocosms, in contrast to the strong consumer effect in the natural stream, suggests that both timing and diversity of returning consumers are important to their overall influence on stream recovery patterns. Although we found that consumers significantly altered ecosystem structure and function in a system experiencing rapid changes in abiotic and biotic factors following disturbance, consumer effects diminished over time and trajectories converged to similar states with respect to primary producers, in spite of differences in consumer colonization history. Thus, consumer impacts can be substantial in recovering ecosystems and are likely to be dependent on the disturbance regime and diversity of the consumer community.
THE INTERRELATIONSHIP OF PULP AND PERIODONTAL DISEASE.

Abstract In order to ascertain whether or not a relationship exists between periodontal and pulpal lesions, eighty-five teeth with periodontal lesions were examined histologically. Prior to extraction, subjective symptoms and the results of clinical tests were recorded. In addition, a medical and dental history was elicited. In many teeth a profusion of lateral and accessory canals and foramina were found, especially in the bifurcation and trifurcation regions of molars. Where the roots were fused with cementum, accessory canals were frequently seen. The pulps of only five teeth (6 per cent) were found to be uninvolved. Atrophic pulps were found in twenty-three teeth (27 per cent). The pulps were inflamed in forty-two teeth (49 per cent) and totally necrotic in fifteen teeth (18 per cent). These observations appeared to indicate that periodontal lesions produced a degenerative effect on the pulps of the involved teeth. In order to separate the effects of caries or operative procedures in the pulps of those teeth with periodontal involvements, we examined thirty-two periodontally involved teeth in which there was no evidence of caries or restorations. Among this group, twelve teeth (37 per cent) had pulps exhibiting various degrees of atrophy and twelve teeth (37 per cent) had inflammatory pulp lesions. In three teeth the pulps were completely necrotic. Further analyses indicated that pulps subjected to a combination of pulp and periodontal irritants showed a greater incidence of inflammatory reactions than those subjected to operative procedures alone. Pulp lesions were found to have an effect on the severity of the periodontal lesion. Inflammation of the periodontal membranes from inflamed and necrotic pulps was readily spread through lateral canals and accessory foramina, especially in molars. Also, extensive apical granulomas caused resorption of the crest of the interradicular alveolar ridge. Thus, retention of these teeth could be accomplished only through combined endodontic and periodontal therapy. Pain in periodontally involved teeth was also investigated. Atrophy or inflammation of the pulp was responsible for the greatest incidence of pain. The pain incidence appeared to increase when caries or restorations were present. Thermal responses in teeth with periodontal lesions increased significantly when the pulps were found to be inflamed, but there was no correlation between the type of pulp inflammation and a specific thermal test. The patients' complaints relating to pain on thermal stimuli were not found to be reliable indicators of the state of the pulp in periodontally involved teeth.
Cross-fostering immediately after birth induces a permanent microbiota shift that is shaped by the nursing mother

Current research has led to the appreciation that there are differences in the commensal microbiota between healthy individuals and individuals that are predisposed to disease. Treatments to reverse disease pathogenesis through the manipulation of the gastrointestinal (GI) microbiota are now being explored. Normalizing microbiota between different strains of mice in the same study is also needed to better understand disease pathogenesis. Current approaches require repeated delivery of bacteria and large numbers of animals and vary in treatment start time. A method is needed that can shift the microbiota of predisposed individuals to a healthy microbiota at an early age and sustain this shift through the lifetime of the individual. We tested cross-fostering of pups within 48 h of birth as a means to permanently shift the microbiota from birth. Taxonomical analysis revealed that the nursing mother was the critical factor in determining bacterial colonization, instead of the birth mother. Data was evaluated using bacterial 16S rDNA sequences from fecal pellets and sequencing was performed on an Illumina Miseq using a 251 bp paired-end library. The results show that cross-fostering is an effective means to induce an early and maintained shift in the commensal microbiota. This will allow for the evaluation of a prolonged microbial shift and its effects on disease pathogenesis. Cross-fostering will also eliminate variation within control models by normalizing the commensal microbiota between different strains of mice.
Chelation therapy in acute iron poisoning

Deferoxamine, a highly specific iron chelating agent, was used in association with supportive therapy in 14 children with acute iron intoxication of mild to moderate severity. The serum iron levels and iron excretion of these patients were compared with those of 8 patients who received only supportive therapy. A rapid drop in serum iron levels occurred in both groups. Increased urinary excretion of iron occurred in patients receiving deferoxamine. All of the children recovered. It is recommended that this chelating agent not be used routinely in mild cases of iron intoxication.
Rate of solute transport out of emulsion droplets in micron size range

An experimental verification of the theory for rate of external-phase-diffusion-controlled solute transport from emulsion droplets in the micron size range has been carried out. The Coulter counter was employed to follow the change in size distribution in aqueous sodium chloride solutions of dibutyl phthalate droplets with time. The rate was proportional to particle radius according to theory, and the diffusion coefficient of dibutyl phthalate calculated from data and theory agreed well with the Stokes-Einstein law predictions. The effect of the presence of a water immiscible component in the dibutyl phthalate droplet was also studied.
Functional Neuroimaging of Sleep Disorders

Functional neuroimaging methods provide a means to understand brain function in patients with sleep disorders. This paper summarizes functional neuroimaging findings in sleep disorders patients, and studies addressing the pharmacology of sleep and sleep disorders. Areas in which functional neuroimaging methods may be helpful in sleep medicine, and in which future development is advised, include: 1) clarification of pathophysiology; 2) aid in differential diagnosis; 3) assessment of treatment response; 4) guiding new drug development; and 5) monitoring treatment response.
Reliable nonlinear parameter estimation using interval analysis: error-in-variable approach

Abstract Parameter estimation is a key problem in the development of process models, both steady- and unsteady-state, and thus is an important issue in both process design and control. The error-in-variable (EIV) approach differs distinctly from the standard approach in that measurement errors in both dependent and independent system variables are taken into account when formulating the objective function in the parameter estimation problem. It is not uncommon for the objective function in nonlinear parameter estimation problems to have multiple local optima. However, the usual methods used to solve these problems are local methods that offer no guarantee that the global optimum, and thus the best set of model parameters, has been found. We demonstrate here a technique, based on interval analysis, that can solve the EIV parameter estimation problem with complete reliability, providing a mathematical and computational guarantee that the global optimum is found. As examples, we consider the estimation of parameters in both steady and unsteady-state models, including a vapor—liquid equilibrium (VLE) model, a CSTR model, and a reaction kinetics model.
Cultural Identity and Diversity in Deaf Education.

The article begins with a discussion of the sociocultural model of a deaf child as a member of a bilingual minority and examines its implications for deaf education. A case is made for recognizing ethnic diversity within the deaf community in designing and implementing educational programs and policies that strengthen the self-identities of deaf children. Several issues related to the accommodation of the diversity of deaf learners are discussed illustrating how such accommodation would enhance their educational experiences. The use of technology, its potential to accommodate diverse deaf learners, and its influence on the deaf community are also discussed.
Academic Success for Students of Color . . . At What Cost? The Importance of School Context at Birch High School

Kiara, an African American rising freshman, has aspirations to become a medical doctor. She enrolls at Birch High School because of the reputation of the principal, Mr. Brown, whose vision for acad...
Stability and Steady-State Vibrations in a High-Speed Slider-Crank Mechanism

The research presented in this paper is an analytical study of the vibrations associated with planar mechanical linkages. Specifically, the vibrations of a high-speed slider-crank mechanism with a uniform elastic connecting rod and a rigid crank are studied. The elastic connecting rod, with distributed mass, is taken to be externally, viscously damped with a concentrated mass present at its sliding end. The equations governing the longitudinal and transverse vibrations of the elastic connecting rod are derived, a small parameter is found, and the solution is developed as an asymptotic expansion in terms of this small parameter with the aid of the Krylov-Bogoliubov method of averaging. The elastic stability is studied and the steady-state solutions for both the longitudinal and transverse vibrations of the connecting rod are obtained.
Genetic programs of epithelial cell plasticity directed by transforming growth factor-β

Epithelial–mesenchymal transitions (EMTs) are an essential manifestation of epithelial cell plasticity during morphogenesis, wound healing, and tumor progression. Transforming growth factor-β (TGF-β) modulates epithelial plasticity in these physiological contexts by inducing EMT. Here we report a transcriptome screen of genetic programs of TGF-β-induced EMT in human keratinocytes and propose functional roles for extracellular response kinase (ERK) mitogen-activated protein kinase signaling in cell motility and disruption of adherens junctions. We used DNA arrays of 16,580 human cDNAs to identify 728 known genes regulated by TGF-β within 4 hours after treatment. TGF-β-stimulated ERK signaling mediated regulation of 80 target genes not previously associated with this pathway. This subset is enriched for genes with defined roles in cell–matrix interactions, cell motility, and endocytosis. ERK-independent genetic programs underlying the onset of EMT involve key pathways and regulators of epithelial dedifferentiation, undifferentiated transitional and mesenchymal progenitor phenotypes, and mediators of cytoskeletal reorganization. The gene expression profiling approach delineates complex context-dependent signaling pathways and transcriptional events that determine epithelial cell plasticity controlled by TGF-β. Investigation of the identified pathways and genes will advance the understanding of molecular mechanisms that underlie tumor invasiveness and metastasis.
A Hierarchical Network Controls Protein Translation during Murine Embryonic Stem Cell Self-Renewal and Differentiation

Stem cell differentiation involves changes in transcription, but little is known about translational control during differentiation. We comprehensively profiled gene expression during differentiation of murine embryonic stem cells (ESCs) into embryoid bodies by integrating transcriptome analysis with global assessment of ribosome loading. While protein synthesis was parsimonious during self-renewal, differentiation induced an anabolic switch, with global increases in transcript abundance, polysome content, protein synthesis, and protein content. Furthermore, 78% of transcripts showed increased ribosome loading, thereby enhancing translational efficiency. Transcripts under exclusive translational control included the transcription factor ATF5, the tumor suppressor DCC, and the beta-catenin agonist Wnt1. We show that a hierarchy of translational regulators, including mTOR, 4EBP1, and the RNA-binding proteins DAZL and GRSF1, control global and selective protein synthesis during ESC differentiation. Parsimonious translation in pluripotent state and hierarchical translational regulation during differentiation may be important quality controls for self-renewal and choice of fate in ESCs.
Efficient, two-photon pumped green upconverted cavity lasing in a new dye

Abstract Two-photon pumped green cavity lasing has been observed in a solution of a new dye in N,N-dimethyl formamide (DMF). The dye, 4-[N-(2-hydroxyethyl)-N-(methyl) amino phenyl]-4′-(6-hydroxyhexyl sulfonyl) stilbene, abbreviated as APSS, shows a strong two-photon absorption induced fluorescence when excited at 800 nm. The molecular two-photon absorption cross section was measured to be σ 2 = 1.5 × 10 −19 cm 4 /GW or σ ′ 2 = 3.8 × 10 −47 cm 4 /photon/s, and is 1 to 2 orders of magnitude higher than Rhodamine 6G. The peak of the lasing spectrum was around 555 nm, and is to the best of our knowledge, the shortest wavelength obtained from a two-photon pumped dye laser. The conversion efficiency from the absorbed pump energy to the lasing output energy was as high as 2.8%. The absorption and the fluorescence spectra of the new dye, along with the spectral and temporal behavior of the two-photon pumped lasing output is presented.
Comparison of EGFR Dimer Stabilities in the Presence and Absence of the Ligand EGF

EGFR is a member of the ErbB family of receptors. EGFR consists of a glycosylated extracellular domain, a single pass transmembrane segment, and an intracellular domain with kinase activity. Mutations or increased expression of this receptor have been linked to human cancers. EGF is a ligand that binds and activates EGFR. It is generally accepted that EGF binding increases the stability of EGFR dimers. However, the magnitude of this stabilizing effect has not been quantified yet. Here, we used spectral FRET, combined with two photon microscopy, to study the dimerization of EGFR in plasma membranes. We observed significant stabilization of the EGFR dimer in the presence of the EGF ligand. These data allowed us to quantify the increase in EGFR dimer stability upon EGF binding.
Effects of epidermal turnover on the dynamics of percutaneous drug absorption

A method was proposed to evaluate the effect of desquamation on the time to reach steady-state drug delivery rate and concentration in the skin layers. Evaluation of the effective time constant, in terms of key physicochemical properties of the system, does not require solving the fundamental equations. Laplace transforms and the residue theorem were applied to monitor the evolution of the medicament in the skin layers and subsequent uptake into the systemic circulation. The equilibrium flux and the effective time constant declined with increasing stratum corneum turnover velocity and were not affected by the speed at which cells in the viable epidermis moved toward the surface of the skin. Ninety eight percent of the equilibrium penetration rate was reached after four time constants. This dynamic metric helped measure the extent to which high lipophilicity or molecular weight delayed percutaneous drug absorption.
Localized bone marrow transplantation leads to skin allograft acceptance in nonmyeloablated recipients: comparison of intra-bone marrow and isolated limb perfusion.

It has been shown that engraftment of allogeneic bone marrow cells (BMC) induces tolerance to antigen-matched organs, and infusion of a megadose of cells improves the success of engraftment of T-cell-depleted BMC. This study explores intra-bone marrow injection (IB) and isolated limb perfusion (IL) as means of localized bone marrow transplantation (BMT) and assesses their tolerogenic effect. Intravenous (i.v.), IB, and IL infusion of syngeneic and allogeneic whole BMC rescued 90%-100% of myeloablated recipients. Tracing of PKH-labeled cells revealed early systemic dissipation after IB injection, indicating that it was equivalent to i.v. transplantation. In contrast, IL perfusion led to initial localization of donor BMC. BALB/c recipients conditioned with 70 microg/g busulfan had 58% +/- 5% and 44% +/- 4% donor lymphocytes at 4 weeks after i.v. and IL infusion, respectively, of 10(7) whole BMC from B10 donors. This suggests that cells migrated out of the IL femur and seeded other bones. All recipients accepted donor-matched skin grafts and acutely rejected third party grafts. T-cell depletion lowered the engraftment efficiency of i.v.-BMT by 35% (p < 0.001 versus whole BMC), but not when infused IL (p < 0.001). It is concluded that IL-BMT is a procedure for initial localization of donor cells, which is as efficient as i.v.- and IB-BMT in rescue of myeloablated mice, induction of hemopoietic chimerism, and donor-specific immune nonresponsiveness to secondary skin grafts without myeloablative conditioning. The megadose effect achieved by inoculation of a small hemopoietic space improved engraftment of T-cell-depleted BMC. This approach may have clinical applications.
Stereoselectivity of catalytic cyclopropanation reactions. Catalyst dependence in reactions of ethyl diazoacetate with alkenes

Les rendements en produits et les stereoselectivites des reactions de cyclopropanation, catalysees par Rh 2 (OAc) 4 du diazoacetate d'ethyle avec des enols ethers, dienes et simples alcenes sont rapportes et compares aux stereoselectivites des reactions de formation de cyclopropanes catalysees par Rh 6 (Co) 16 , CuCl•P(O-i-Pr) 3 et PdCl 2 •2PhCN
Young’s modulus calculations for cellulose Iβ by MM3 and quantum mechanics

Quantum mechanics (QM) and molecular mechanics (MM) calculations were performed to elucidate Young’s moduli for a series of cellulose Iβ models. Computations using the second generation empirical force field MM3 with a disaccharide cellulose model, 1,4′-O-dimethyl-β-cellobioside (DMCB), and an analogue, 2,3,6,2′,3′,6′-hexadeoxy-1,4′-O-dimethyl-β-cellobioside (DODMCB), that cannot make hydrogen bonds reveal a considerable contribution of intramolecular hydrogen bonding to the molecular stiffness of cellulose Iβ; the moduli for DMCB and DODMCB being 85.2 and 37.6 GPa, respectively. QM calculations confirm this contribution with modulus values of 99.7 GPa for DMCB and 33.0 GPa for DODMCB. However, modulus values for DMCB were considerably lower than values previously reported for cellulose Iβ. MM calculations with extended cellulose chains (10–40 glucose units) resulted in modulus values, 126.0–147.5 GPa, more akin to the values reported for cellulose Iβ. Comparison of the cellodecaose model, 1,4′-O-dimethyl-β-cellodecaoside (DMCD), modulus with that of its hydrogen bonding-deficient analogue, 2,3,6,2′,3′,6′-hexadeoxy-1,4′-O-dimethyl-β-cellodecaoside (DODMCD), corroborates the observed stiffness conferred by intramolecular hydrogen bonds; the moduli for DMCD and DODMCD being 126.0 and 63.3 GPa, respectively. Additional MM3 determinations revealed that modulus values were not strongly affected by intermolecular hydrogen bonding, with multiple strand models providing values similar to the single strand models; 87.5 GPa for a 7-strand DMCB model and 129.5 GPa for a 7 strand DMCD model.
The use of fatty acid profile as a potential marker for Brazilian coffee (Coffea arabica L.) for corn adulteration

Fatty acid methyl ester (FAME) composition of the coffee (Coffea arabica L.) varieties Catuai, Catucai, Bourbom, Mundo Novo, Rubi and Topazio known to produce beverage of intermediate, excellent, excellent, intermediate, intermediate and poor quality, respectively, was determined for the first time. Average area % of the FAMEs of the six varieties was: palmitic (38.2), stearic (8.3), oleic (8.6), linoleic (38.5), linolenic (1.6) and arachidic (3.6) acids, respectively. The method was very quick with complete characterization (>99%) of the samples studied being possible in less than 6 min. While these values may provide insights for evaluating the coffee quality, no significant effect (p < 0.05) of coffee variety was found on area % of the FAMEs. In addition, FAMEs of six corn samples, six commercial coffee brands and one commercial coffee sample intentionally contaminated with three levels of corn were compared. Although the linoleic/stearic ratio was significantly different in coffee and corn FAMEs, this probe could not be used a marker to detect corn adulteration in commercial coffees.
Human Immunodeficiency Virus and the Central Nervous System

Neurological disease frequently complicates HIV-1 infection. In addition to opportunistic infections, a syndrome of combined cognitive and motor impairment, referred to as the AIDS dementia complex, has been recognized. While presumed to relate to HIV-1 itself, the pathogenesis of this syndrome remains uncertain. Because of the limited extent of productive brain HIV-1 infection in many cases, and because such infection involves macrophages and microglia rather than cells of neuroectodermal origin, current speculation centers on indirect mechanisms of brain injury including virus- or cell-coded neurotoxins. We review clinical and laboratory studies and also describe models of the interaction of HIV-1 and immune responses that might account for brain injury.
Cyclic adenosine monophosphate regulation of ion transport in porcine vocal fold mucosae.

Objectives/Hypothesis: Cyclic adenosine monophosphate (cAMP) is an important biological molecule that regulates ion transport and inflammatory responses in epithelial tissue. The present study examined whether the adenylyl cyclase activator, forskolin, would increase cAMP concentration in porcine vocal fold mucosa and whether the effects of increased cAMP would be manifested as a functional increase in transepithelial ion transport. Additionally, changes in cAMP concentrations following exposure to an inflammatory mediator, tumor necrosis factor- (TNF) were investigated. Study Design: In vitro experimental design with matched treatment and control groups. Methods: Porcine vocal fold mucosae (N 30) and tracheal mucosae (N 20) were exposed to forskolin, TNF, or vehicle (dimethyl sulfoxide) treatment. cAMP concentrations were determined with enzyme-linked immunosorbent assay. Ion transport was measured using electrophysiological techniques. Results: Thirty minute exposure to forskolin significantly increased cAMP concentration and ion transport in porcine vocal fold and tracheal mucosae. However, 30-minute and 2-hour exposure to TNF did not significantly alter cAMP concentration. Conclusions: We demonstrate that forskolinsensitive adenylyl cyclase is present in vocal fold mucosa, and further, that the product, cAMP increases vocal fold ion transport. The results presented here contribute to our understanding of the intracellular mechanisms underlying vocal fold ion transport. As ion transport is important for maintaining superficial vocal fold hydration, data demonstrating forskolin-stimulated ion transport in vocal fold mucosa suggest opportunities for developing pharmacological treatments that increase surface hydration.
Iron/manganese ratio and manganese content in shield lavas from Ko’olau Volcano, Hawai’i

Precise Fe/Mn ratios and MnO contents have been determined for basalts from the Hawaiian shields of Ko’olau and Kilauea by inductively coupled plasma mass spectrometry. It is well known that the youngest Ko’olau (Makapu’u-stage) shield lavas define a geochemical endmember for Hawaiian lavas in terms of CaO and SiO2 contents and isotopic ratios of O, Sr, Nd, Hf, Pb, and Os. We find that their MnO content is also distinct. Despite the small range in MnO, 0.146 to 0.176 wt%, the precision of our data is su!cient to show that among unaltered Ko’olau lavas MnO content is correlated with Nd‐Hf‐Pb isotopic ratios, La/Nb and Al2O3/CaO elemental ratios, and contents of SiO2, MgO and Na2O + K2O adjusted for olivine fractionation. These trends are consistent with two-component mixing; one endmember is a SiO2-rich, MnO-, and MgO-poor dacite or andesite melt, generated by low degree (10‐20%) partial melting of eclogite. Since this low-MgO endmember (dacite or andesite melt) has very low FeO and MnO contents, mixing of high Fe/Mn dacite or andesite melt with a MgO-rich picritic melt, the other endmember, does not significantly increase the Fe/Mn in mixed magmas; consequently, Ko’olau and Kilauea lavas have similar Fe/Mn. We conclude that the high Fe/Mn in Hawaiian lavas relative to mid-ocean ridge basalt originates from the high MgO endmember in Hawaiian lavas. ! 2007 Elsevier Ltd. All rights reserved.
The Snail family member Worniu is continuously required in neuroblasts to prevent Elav-induced premature differentiation.

Summary Snail family transcription factors are best known for regulating epithelial-mesenchymal transition (EMT). The Drosophila Snail family member Worniu is specifically transcribed in neural progenitors (neuroblasts) throughout their lifespan, and worniu mutants show defects in neuroblast delamination (a form of EMT). However, the role of Worniu in neuroblasts beyond their formation is unknown. We performed RNA-seq on worniu mutant larval neuroblasts and observed reduced cell-cycle transcripts and increased neural differentiation transcripts. Consistent with these genomic data, worniu mutant neuroblasts showed a striking delay in prophase/metaphase transition by live imaging and increased levels of the conserved neuronal differentiation splicing factor Elav. Reducing Elav levels significantly suppressed the worniu mutant phenotype. We conclude that Worniu is continuously required in neuroblasts to maintain self-renewal by promoting cell-cycle progression and inhibiting premature differentiation.
CSF-1 receptor structure/function in MacCsf1r–/– macrophages: regulation of proliferation, differentiation, and morphology

CSF-1 is the major regulator of tissue macrophage development and function. A GM-CSF-dependent, CSF-1 receptor (CSF-1R)-deficient F4/80(hi)Mac-1(+)Gr1(-)CD11c(+) bone marrow macrophage (BMM) line (MacCsf1r-/-) was developed to study the roles of the eight intracellular CSF-1R tyrosines phosphorylated upon receptor activation. Retroviral expression of the wild-type CSF-1R rescued the CSF-1-induced survival, proliferation, differentiation, and morphological characteristics of primary BMM. Mutation of all eight tyrosines failed to rescue, whereas the individual Y --> F mutants (544, 559, 697, 706, 721, 807, 921, 974) rescued these CSF-1-inducible phenotypes to varying degrees. The juxtamembrane domain Y559F and activation loop Y807F mutations severely compromised proliferation and differentiation, whereas Y706, Y721F, and Y974F mutations altered morphological responses, and Y706F increased differentiation. Despite their retention of significant in vitro tyrosine kinase activity, Y559F and Y807F mutants exhibited severely impaired in vivo receptor tyrosine phosphorylation, consistent with the existence of cellular mechanisms inhibiting CSF-1R tyrosine phosphorylation that are relieved by phosphorylation of these two sites. The MacCsf1r-/- macrophage line will facilitate genetic and proteomic approaches to CSF-1R structure/function studies in the major disease-related CSF-1R-expressing cell type.
Permeation of Permanent Gases through Liquid Membranes

Abstract The permeation of the permanent gases, He, O2, CO2, and N2, through liquid membranes was investigated by two experimental methods. The first procedure utilized the simultaneous counterdiffusion of two pure gases through an aqueous-surfactant bubble membrane according to the technique developed by Cook. In the second, the transfer rate of a single pure gas was measured by utilizing a spherical soap bubble. Comparison of the data obtained from the two different tests indicated that these gas-liquid systems behaved ideally. That is, there were no observed interactions for the binary mixtures which could not be predicted from the behavior of the pure components. Finally, nonaqueous, silicone oil membranes were investigated as potential separative barriers. These oil films yielded the same separation factors as previously reported for silicone rubber membranes used in the separation of binary gas mixtures.
Antithrombin activity in children with chylothorax.

Objective: To determine whether increased antithrombin loss is present in children with chylothorax after cardiac surgery. Methods: Plasma and pleural effusion samples of children with chylous and non-chylous pleural effusion were assayed for antithrombin activity. Results: Ten children with chylothorax and five children with non-chylous pleural effusion were investigated. There was statistically significant increase in mean antithrombin activity in chylous samples (32.2 11.4%) compared to non-chylous samples (14.4 13.9%), and significant decrease in plasma of children with chylothorax (44.6 15.4%) compared to children with non-chylous pleural effusion (69.9 22.4%). Seven of 10 children with chylous and none of the children without chylous developed thrombosis (p < 0.007). Conclusions: Increased loss of antithrombin is present in children with chylothorax, potentially predisposing these children to an increased risk of thrombosis. Repeated antithrombin substitution should be considered in critically ill children with chylothorax. # 2005 Elsevier B.V. All rights reserved.
A Historical Review of Mother and Child Programs for Incarcerated Women

Programs for incarcerated mothers and their children have received little scholarly attention over the years. This article presents a historical review and discussion of programs for incarcerated mothers and their children in the United States. Recurring themes in the history of these programs include the pervasive effects of race and class, the state's attempt to regulate and control women's minds and bodies, and the persistent dilemmas posed by the presence of mothers in prison. The article begins with an examination of historical influences from England and continues with an overview of programs in the United States from the early 1800s to the present. A discussion and recommendations for further research are provided.