cssi/SciSciGPT-SciSciNet huggingface dataset:
Inhibition of protein and lipid sulfation in oligodendrocytes blocks biological responses to FGF-2 and retards cytoarchitectural maturation, but not developmental lineage progression

We have examined the interfaces between protein and lipid sulfation, the response of progenitor cells to specific growth factors, and developmental lineage progression. The experimental system used is the oligodendrocyte (OL), the cell responsible for myelination of axons in the central nervous system. The ability to regulate the growth and differentiation of oligodendrocytes in primary cultures growing in defined medium offers a particularly attractive model for these interrelated areas of cell and developmental biology. Sulfation was inhibited in this system by growing cells in sodium chlorate, a competitive inhibitor of sulfation. Four principal conclusions are drawn from the data. First, heparan sulfate proteoglycan is a necessary cofactor for the environmental regulation by FGF-2 of nontransformed oligodendrocyte progenitors, including both the mitogenic response and the inhibition of terminal differentiation at a specific stage of the lineage. Second, the differentiation of oligodendrocyte progenitors from an early to a mature stage can occur in the absence of sulfation. Third, however, the formation of cellular processes and myelin-like sheets is retarded, leading to the prediction that sulfated molecules are critically involved in aspects of oligodendrocyte differentiation directly relating to myelination per se. Fourth, the developmental proligodendroblast antigen, POA, is a sulfated molecule. The results provide clear evidence for the importance of sulfation for the responses of OL progenitors to FGF-2 and for OL cytoarchitectural maturation, while demonstrating an ability of OL progenitors to undergo lineage progression in its absence.
Assembly and disassembly of bare chips using on-substrate linear micro vibromotor arrays

A new method for the on-substrate fine positioning of micro/meso-scale discrete components is proposed, where component positions are finely adjusted using micro linear sliders and fixtures on the substrate. Each micro linear slider is actuated by vibratory impacts exerted by two pairs of micro cantilever impacters. These micro cantilever impacters are selectively resonated by shaking the entire substrate with a piezoelectric vibrator realizing forward and backward slider motion to facilitate assembly and disassembly of a micro component on the substrate. An array of the prototype externally-resonated linear micro vibrometers is fabricated using the MCNC MUMPS service. These prototypes are tested for forward and backward motion via external vibration applied by a piezoelectric stack vibrator. The linear micro vibromotor array is to be integrated in a on-chip micro assembly device where the assembly of micro/meso-scale discrete components (bare chips) on a common substrate is done by the combination of vibratory palletization for gross positioning, and linear micro vibromotor for fine positioning.
Structural studies on FK-506, cyclosporin A and their immunophilin complexes

The immunosuppressants FK-506 and cyclosporin A (CsA), along with their macromolecular receptors FKBP12 and cyclophilin A (CyPA), have become important targets for structure-based drug design. In the last few years X-ray diffraction and NMR spectroscopy have combined to provide high-resolution structures of FK-506, CyA, FKBP12, CyPA, FKBP12-FK-506, CyPA-CyA, and other complexes. This review summarizes these structural studies and some of their implications. Because the immunosuppressant-immunophilin complex forms a composite binding surface that interacts with yet another protein, structure-based drug design in this area is unusually challenging.
Relative DNA content of cells in Festuca arundinacea and Dactylis glomerata calli of different ages.

Abstract Experiments were conducted to determine changes in nuclear DNA content in cells of tall fescue ( Festuca arundinacea ) and orchardgrass ( Dactylis glomerata ) embryo-derived calli ranging in age from 3 to 24 weeks. Calli were induced and maintained on a modified Murashige-Skoog medium containing 22.6 μM of 2,4-dichlorophenoxyacetic acid. Calli were divided with one pieces being fixed in 3:1 ethanol: acetic acid and the other transfered too fresh maintenance medium at 3, 6, 9, 12, 18 and 24 weeks after initial plating of mature embryos. Fixed calli were processed through a cold hydrolysis technique and Feulgen stained. Stained callus pieces were squashed in 45% acetic acid and relative DNA contents were measured with a microscope cytophotometer. Results showed predominately 2C nuclei in calli of both species regardless of callus age. More cells with high DNA contents ( ≧4 C ) were found in orchardgrass than in tall rescue calli. The proportion of 2C cells increased with increasing callus age, especially in tall fescue. Cells of various sizes and shapes were observed in calli of both species and very large cells with small (2C) nuclei were common in callus tissue of all ages. The mitotic index was low and decreased with increasing callus age, especially in tall fescue. Nuclei with 2C4C, 4C8C, or less than 2C, amounts of DNA may be due to anuploidy.
Large variability in radiation dose from CT-guided thoracic biopsies appears driven by differences in technical factor selection

Purpose To study factors associated with radiation dose variability from CT-guided thoracic biopsies performed at other institutions. Materials and Methods We conducted an IRB-approved retrospective review of CT-guided biopsy procedures performed between June 2009 and July 2011 that were submitted for digitization in our PACS but performed at other institutions. Complete CT dose reports and images were required. Effective dose estimates were obtained using an ED/DLP conversion factor of 0.017. Studies were partitioned into three imaging phases for analysis: pre-procedure localization, procedural guidance and post-procedure assessment. Technical parameters during CT imaging, biopsy target and patient factors were analyzed relative to effective radiation dose. Results 35 thoracic biopsies were identified from 18 institutions. Of 23 (66%) with available dose reports, 21 (60%) had complete data for analysis (11 females, 10 males; median 59 years). Biopsy targets included 15 solid lung nodules (median 25 mm, range 10-116 mm) and 6 chest wall lesions (median 41 mm, range 18-107 mm). Total estimated effective dose varied 27-fold from 1.6 - 43 mSv (9.4 mSv median). Pre-procedure imaging accounted for 48% of total procedure dose on average. Procedural guidance scans averaged 35% of total dose (median 5 scans, range 2-18). Post-procedure CT scans were obtained in 15 cases, accounting for 17% of dose. Comparing biopsies with dose ≤25th percentile (≤4.6 mSv) to those with dose ≥75th percentile (≥21 mSv), there was no difference in patient body weight (p=0.59), lesion size (p=0.39), skin-to-lesion distance (p=0.94) or number of guidance CT scans required (≤5 v >5, p=0.57). Dose from all three phases of biopsy imaging was significantly lower for those in the lowest dose quartile (p Conclusion Thoracic biopsy procedures performed at multiple other institutions showed substantial dose variability, apparently more related to technical factor selection than patient or lesion characteristics.
Functional and structural changes due to a serine to alanine mutation in the active-site flap of enolase.

Crystallographic and kinetic methods have been used to characterize a site-specific variant of yeast enolase in which Ser 39 in the active-site flap has been changed to Ala. In the wild-type enzyme, the carbonyl and hydroxyl groups of Ser 39 chelate the second equivalent of divalent metal ion, effectively anchoring the flap over the fully liganded active site. With Mg(2+) as the activating cation, S39A enolase has <0.01% of wild-type activity as reported previously [J.M. Brewer, C.V. Glover, M.J. Holland, L. Lebioda, Biochim. Biophys. Acta 1383 (2) (1998) 351-355]. Measurements of (2)H kinetic isotope effects indicate that the proton abstraction from 2-phosphoglycerate (2-PGA) is significantly rate determining. Analysis of the isotope effects provides information on the relative rates of formation and breakdown of the enolate intermediate. Moreover, assays with different species of divalent metal ions reveal that with S39A enolase (unlike the case of wild-type enolase), more electrophilic metal ions promote higher activities. The kinetic results with the S39A variant support the notions that a rate-limiting product release lowers the activity of wild-type enolase with more electrophilic metal ions and that the metal ions are used to acidify the C2-proton of 2-PGA. The S39A enolase was co-crystallized with Mg(2+) and the inhibitor phosphonoacetohydroxamate (PhAH). The structure was solved and refined at a resolution of 2.1 A. The structure confirms the conjecture that the active-site flap is opened in the mutant protein. PhAH chelates to both Mg ions as in the corresponding structure of the wild-type complex. Positions of the side chains of catalytic groups, Lys 345 and Glu 211, and of "auxiliary" residues Glu 168 and Lys 396 are virtually unchanged relative to the complex with the wild-type protein. His 159, which hydrogen bonds to the phosphonate oxygens in the wild-type complex, is 5.7 A from the closest phosphonate oxygen, and the loop (154-166) containing His 159 is shifted away from the active center. A peripheral loop, Glu 251-Gly 275, also moves to open access to the active site.
The Vesicle Trafficking Protein Sar1 Lowers Lipid Membrane Rigidity

The sculpting of membranes into dynamic, curved shapes is central to intracellular cargo trafficking. Though the generation of membrane curvature during trafficking necessarily involves both lipids and membrane-associated proteins, current mechanistic views focus primarily on the formation of rigid cages and curved scaffolds by protein assemblies. Here we report on a different mechanism for the control of membrane deformation, unrelated to the imposition of predefined curvature, involving modulation of membrane material properties: Sar1, a GTPase that regulates vesicle trafficking from the endoplasmic reticulum, lowers the rigidity of the lipid bilayer membrane to which it binds. In vitro assays in which optically trapped microspheres create controlled membrane deformations revealed a monotonic decline in bending modulus as a function of Sar1 concentration, down to nearly zero rigidity, indicating a dramatic lowering of the energetic cost of curvature generation. This is the first demonstration that a vesicle trafficking protein lowers the rigidity of its target membrane, leading to a new conceptual framework for vesicle biogenesis.
Public priorities for efficiency in air quality management

The results of a pilot study of the priorities that concerned parties assigned to efficiency attributes of air quality management measures are reported. The analysed priorities were those of the members of: (a) two task forces appointed to assist the South Coast Air Quality Management District of California evaluate alternative measures; and (b) the gallery , during the task force meetings. Major findings include: (a) a great majority of concerned parties assigned a more than two-times greater priority to the beneficial impacts of measures than to the negative impacts; (b) concerned parties with the highest priority for the beneficial impacts appear to disagree on the priority of specific categories of these impacts; (c) concerned parties with similar special interest affiliations and expertises hold statistically different priorities; and (d) distinct patterns of priorities exist necessitating separate efficiency assessments of measures in order to better understand the reasons for support (opposition) of each measure and the strength of this support. According to these findings, even when efficiency is chosen as the only criterion, a more involved process is needed than a pecuniary benefit-cost analysis. The objective of this process should be a multi-attribute evaluation of air quality management measures with the proactive participation of interested parties. Only such a process can assist conflict management and a more efficacious implementation of decisions.
Two eyes are better than one: Some reflections on the importance of having more than one viewpoint in mathematical modelling and other disciplines

Written in the form of a conversation between a mathematician, an engineer, and a palaeographer, this paper attempts to explore the value of complementary viewpoints: the physical and mathematical in modelling, the logical and the imaginative in mathematics, the historical and the artistic in palaeography.
Airway secretory IgA concentrations in patients with lung cancer. Evaluation of the uninvolved lung.

To determine whether concentrations of the primary airway immunoglobulins (SIgA, IgG) are altered in the uninvolved lung of patients with lung cancer, we determined concentrations of SIgA and IgG in bronchial washings recovered from a proximal airway of the uninvolved lung in 24 patients with lung cancer and in ten patients with benign lung disease. When standardized for the amount of total protein recovered (SIgA/TP, IgG/TP), bronchial washings recovered from the uninvolved lung of lung cancer patients demonstrated a significantly decreased SIgA/TP ratio compared to control subjects (.14 ± .02 vs .31 ± .05, SEM, p
Cometabolism of pentachlorophenol by microbial species

Abstract Pentachlorophenol (PCP) cometabolism in the presence of dextrose was investigated with a pure culture Pseudomonas cepacia and an acclimated mixed culture developed from a local activated sludge plant. The Ps. cepacia cells degraded PCP up to 50 mg/l without any significant lag, but at higher PCP concentrations (>50 mg/l and up to 100 mg/l) there was a significant lag period (up to 30 h) before the degradation started. Overall, PCP degradation was about 80% in these systems. PCP was found to be a non-competitive inhibitor of Ps. cepacia with an inhibition constant (Ki) of 222 mg/l. The Ps. cepacia cells were unable to use PCP as a sole carbon and energy source. The mixed culture cometabolized PCP in the presence of dextrose at rates somewhat similar to that of Ps. cepacia up to PCP concentrations of 100 mg/l. These cells, acclimated to PCP at a particular concentration, degraded PCP up to the acclimation concentration fairly rapidly, but at PCP concentrations higher than the acclimation concentration, the degradation rates were much slower. The mixed culture cells could be progressively acclimated to using up to 100 mg/l PCP as sole carbon and energy source with degradation rates similar to those when dextrose was present as a primary metabolite. The PCP and dextrose utilization by the mixed culture was characterized by a diauxic growth pattern.
Duration of the phases of mechanical systole in infants and children

Abstract In the present investigation, determinations of the duration of mechanical systole and left ventricular ejection were made from simultaneous recordings of the heart sounds and the carotid or axillary arterial pulsation in older children and in mature and premature neonatal infants without cardiovascular disease. In older children and mature neonates with heart rates ranging from 69 to 196 beats/min., both duration of total systole and left ventricular ejection time diminished linearly and in parallel with increasing heart rate up to a level of 150 beats/min. At high levels of heart rate the phases of systole diminished more gradually with increasing heart rate. The isovolumetric contraction time tended to remain constant throughout the range of heart rates studied. Among the premature neonates there was a wider distribution in the measured intervals, and left ventricular ejection time tended to be higher at any level of heart rate. The prolonged ejection time in this group can in part be attributed to the presence of anemia.
Impact of aging mechanism on model simulated carbonaceous aerosols

Abstract. Carbonaceous aerosols including organic carbon and black carbon have significant implications for both climate and air quality. In the current global climate or chemical transport models, a fixed hydrophobic-to-hydrophilic conversion lifetime for carbonaceous aerosol (τ) is generally assumed, which is usually around one day. We have implemented a new detailed aging scheme for carbonaceous aerosols in a chemical transport model (GEOS-Chem) to account for both the chemical oxidation and the physical condensation-coagulation effects, where τ is affected by local atmospheric environment including atmospheric concentrations of water vapor, ozone, hydroxyl radical and sulfuric acid. The updated τ exhibits large spatial and temporal variations with the global average (up to 11 km altitude) calculated to be 2.6 days. The chemical aging effects are found to be strongest over the tropical regions driven by the low ozone concentrations and high humidity there. The τ resulted from chemical aging generally decreases with altitude due to increases in ozone concentration and decreases in humidity. The condensation-coagulation effects are found to be most important for the high-latitude areas, in particular the polar regions, where the τ values are calculated to be up to 15 days. When both the chemical aging and condensation-coagulation effects are considered, the total atmospheric burdens and global average lifetimes of BC, black carbon, (OC, organic carbon) are calculated to increase by 9% (3%) compared to the control simulation, with considerable enhancements of BC and OC concentrations in the Southern Hemisphere. Model evaluations against data from multiple datasets show that the updated aging scheme improves model simulations of carbonaceous aerosols for some regions, especially for the remote areas in the Northern Hemisphere. The improvement helps explain the persistent low model bias for carbonaceous aerosols in the Northern Hemisphere reported in literature. Further model sensitivity simulations focusing on the continental outflow of carbonaceous aerosols demonstrate that previous studies using the old aging scheme could have significantly underestimated the intercontinental transport of carbonaceous aerosols.
Small Solutions for Big Problems: The Application of Nanoparticles to Brain Tumor Diagnosis and Therapy

Nanoparticles have the potential for advancing the diagnosis, operative management and adjuvant therapy brain tumors in the future. Nanoparticle-based MR contrast agents have the potential to uncover portions of tumor, especially along the tumor-brain interface, that would have been unclear with traditional gadolinium-enhanced MRI. In addition, several nanoparticles, developed with the objective of allowing the surgeon to see tumor margins intraoperatively, may ultimately enable neurosurgeons to improve the extent of brain tumor resection. Moreover, the delivery of chemotherapy and non-traditional therapies to brain tumors will likely be greatly improved by nanoparticle based-drug delivery devices. As our knowledge of their pharmacology and long-term health effects expands, nanoparticles are likely to play a central role in the future management of the brain tumor patient.
ERK activation by GM-CSF reduces effectiveness of p38 inhibitor on inhibiting TNFα release

Abstract Tumor necrosis factor α (TNFα), a pro-inflammatory factor, plays an important role in many inflammatory diseases. Inhibition of p38 is being pursued as a pharmaceutical treatment to reduce TNFα release. Since a variety of cytokines and factors may exist at different amounts in patients, we explored how differences in the cytokine environment impact p38 inhibitor potency. Cytokine co-stimulation with LPS was compared against LPS stimulation alone. In both differentiated U937 cells and peripheral monocytes, GM-CSF co-stimulation with LPS increased TNFα release and led to an increased residual TNFα levels with p38 inhibitor. Adding MEK inhibitor in the presence of p38 inhibitor further reduced TNFα release suggesting that the ERK pathway plays a role in GM-CSF induced reduction of the p38 inhibitor potency. When cells were stimulated with different concentrations of LPS and GM-CSF, the minimal TNFα level obtained by MEK inhibitor was not dependent on the stimulation condition; while it was dependent on GM-CSF level for p38 inhibitor. TNFα release in the presence of combinations of p38 and MEK inhibitors under different stimulation conditions was measured. A linear model was created using the initial relative ERK and p38 phosphorylation levels and p38 and MEK inhibitor concentrations to accurately predict released TNFα level, suggesting these four parameters are sufficient to predict TNFα levels. We then used the model to show that with same TNFα levels, higher ERK pathway activity reduces p38 inhibitor potency. These results suggest that p38 inhibitor will be a more potent anti-TNFα therapy for patients with low ERK pathway activity.
Ferromagnetic movements of middle ear implants and stapes prostheses in a 3-T magnetic resonance field.

Hypothesis A 3-T magnetic resonance field may cause motion or displacement of middle ear implants not seen in studies with 1.5-T magnets. Background Previous publications have described the safety limitations of some otologic implants in 1.5-T magnetic resonance fields. Several company-wide recalls of implants were issued. No studies to date have been reported for otologic implants within a 3-T magnetic resonance field, nor have there been comparisons with a 1.5-T field strength. Methods Eighteen commonly used middle ear implants and prostheses were selected. In Part 1, the prostheses were placed in Petri dishes and exposed to a 3-T magnetic resonance field. In Part 2, the particular prostheses that showed movement in Part 1 were placed into their intended use positions within temporal bone laboratory specimens and exposed to a 3-T field. Both parts were repeated in a 1.5-T field. Results In Part 1, three prostheses moved dramatically from their start positions when exposed to the 3-T magnetic resonance field. In Part 2, the three particular prostheses that showed movement in Part 1 showed no gross displacement or movement from their start positions within the temporal bone laboratory specimens. No implants moved in the 1.5-T field in either Part 1 or Part 2. Conclusion Certain stapes prostheses move dramatically in Petri dishes in 3-T fields. When placed into temporal bone laboratory specimens, the same prostheses show no signs of movement from the surgical site in a 3-T field, and it appears that the surgical position holds the implants firmly in place. Results of published 1.5-T field studies should not be used directly for safety recommendations in a 3-T magnetic resonance. Heat, voltage induction, and vibration during exposure to the magnetic resonance fields should be considered as additional possible safety issues. Preference should be given to platinum and titanium implants in manufacturing processes and surgical selection.
Calculation of the Vibrationally Resolved, Circularly Polarized Luminescence of d‐Camphorquinone and (S,S)‐trans‐β‐Hydrindanone

Circularly polarized luminescence (CPL), the differential emission of left- and right-handed circularly polarized light from a molecule, is modeled by using time-dependent density functional theory. Calculations of the CPL spectra for the first electronic excited states of d-camphorquinone and (S,S)-trans-beta-hydrindanone under the Franck-Condon approximation and using various functionals are presented, as well as calculations of absorption, emission, and circular dichroism spectra. The functionals B3LYP, BHLYP, and CAM-B3LYP are employed, along with the TZVP and aug-cc-pVDZ Gaussian-type basis sets. For the lowest-energy transitions, all functionals and basis sets perform comparably, with the long-range-corrected CAM-B3LYP better reproducing the excitation energy of camphorquinone but leading to a blue shift with respect to experiment for hydrindanone. The vibrationally resolved spectra of camphorquinone are very well reproduced in terms of peak location, widths, shapes, and intensities. The spectra of hydrindanone are well reproduced in terms of overall envelope shape and width, as well as the lack of prominent vibrational structure in the emission and CPL spectra. Overall the simulated spectra compare well with experiment, and reproduce the band shapes, emission red shifts, and presence or absence of visible vibrational fine structure.
Outcome of Revision Surgery in Pediatric Spine Deformity Patients

Abstract Study Design Retrospective case series. Objectives To report the complications and outcomes of pediatric revision spine surgery and review the surgical indications and treatment methods. Background Summary Recent reports have shown the necessity of revision spine surgery for pediatric deformities. Many reports have shown the result of revision surgery for pediatric spinal deformity. Materials and Methods We conducted a retrospective review of 638 patients with pediatric spinal deformity who were treated with surgery from 1996 to 2007. We identified 50 patients who underwent revision spinal fusion surgery with a minimum of 3 years of follow-up. Results Mean follow-up was 4 years (range, 3-8.3 years). The diagnosis at index surgery was idiopathic scoliosis in 18 patients, congenital scoliosis in 13, neuromuscular scoliosis in 13, tumor and spinal arteriovenous malformation in 4, burst fracture in thoracic spine in 1, and Scheuermann kyphosis in 1. The primary surgeries were 1 hemi epiphysiodesis, 3 anterior spinal fusions, 4 posterior decompressions, 8 combined anterior and posterior spinal fusions, and 34 posterior spinal fusions. A total of 16 patients had pseudarthrosis, 12 decompensation, 11 progressive kyphosis, 8 crankshaft phenomenon, 2 infections, and 1 junctional degeneration. All 50 reoperations included spinal instrumentation and fusion. The revision surgeries were 2 anterior spinal fusions, 14 posterior fusions, and 34 combined anterior and posterior spinal fusions. Spine arthrodesis was obtained in 98% of patients (49 of 50) and complications occurred in 14% of patients (7 of 50). The Scoliosis Research Society Patient Questionnaire outcomes at the latest follow-up were as follows: total 3.95, function 3.88, pain 3.83, self-image 3.98, and mental health 4.04. Conclusion Pseudarthrosis was the most common indication for revision surgery, and bony union was achieved in 98% with revision surgery. Despite the complications, pediatric revision spine surgery can achieve successful outcomes.
Evaluation of irreversible compression of digitized posterior-anterior chest radiographs

The purpose of this article is to assess lossy image compression of digitized chest radiographs using radiologist assessment of anatomic structures and numerical measurements of image accuracy. Forty posterior-anterior (PA) chest radiographs were digitized and compressed using an irreversible wavelet technique at 10, 20, 40, and 80∶1. These were presented in a blinded fashion with an uncompressed image for A-B comparison of 11 anatomic structures as well as overall quality assessments. Mean error, root-mean square (RMS) error, maximum pixel error, and number of pixels within 1% of original value were also computed for compression ratios from 5∶1 to 80∶1. We found that at low compression (10∶1) there was a slight preference for compressed images. There was no significant difference at 20∶1 and 40∶1. There was a slight preference on some structures for the original compared with 80∶1 compressed images. Numerical measures showed high image faithfulness, both in terms of number of pixels that were within 1% of their original value, and by the average error for all pixels. Our findings suggest that lossy compression at 40∶1 or more can be used without perceptible loss in the representation of anatomic structures. On this finding, we will do a receiver-operator characteristic (ROC) analysis of nodule detection in lossy compressed images using 40∶1 compression.
The influence of environmental factors on the community adjustment of the mentally ill.

The influence of social and geographic variables on the level of community adjustment of 60 former state hospital patients was examined. Community adjustment was operationalized to include measures of instrumental performance, social participation, and satisfaction with community circumstances. Hierarchical regression analysis was used to assess the contribution of social- and community-level predictors. The results of the study suggest that the character of a psychiatric patient's social milieu can influence the success he or she experiences in attempting to adjust to life in the community. Specifically, each of the measures of adjustment was closely related to significant other attitudes, i.e., expectations and tolerance of deviance. The nature of the community in which the patient resides seems to have less of an impact on community adjustment than social-level factors. Overall, the results suggest the importance of a social-environmental strategy as a means of achieving positive changes in patients' adjustment to community living.
Ceramic Nuclear Fuels in the System UO2‐ZrO2‐CaO

Potential nuclear fuels in the system UO2-ZrO2-CaO were investigated. Cubic fluorite-type solid solutions, as indicated by X-ray diffraction patterns, were formed by sintering U3O8-CaO-stabilized ZrO2 compacts in either air or hydrogen. A continuous solid solution was found between urania and stabilized zirconia after sintering in hydrogen at 1750°C. Sintering in air produced a limited solid-solution region in the stabilized zirconia portion of the system at 1450°C. Results on phase identification, oxidation behavior, and water corrosion are presented.
Sp1 and Sp3 control constitutive expression of the human NHE2 promoter by interactions with the proximal promoter and the transcription initiation site.

We have previously cloned the human Na+/H+ exchanger NHE2 gene and its promoter region. In the present study, the regulatory elements responsible for the constitutive expression of NHE2 were studied. Transient transfection assays revealed that the −40/+150 promoter region contains the core promoter responsible for the optimal promoter activity. A smaller fragment, −10/+40, containing the TIS (transcription initiation site) showed minimal activity. We identified a palindrome that overlaps the TIS and binds to the transcription factors Sp1 and Sp3. Mutations in the 5′ flank of the palindrome abolished the Sp1/Sp3 interaction and reduced promoter activity by approx. 45%. In addition, a conserved GC-box centered at −25 was found to play a critical role in basal promoter activity and also interacted with Sp1 and Sp3. An internal deletion in the GC-box severely reduced the promoter activity. Sp1/Sp3 binding to these elements was established using gel-mobility shift assays, confirmed by chromatin immunoprecipitation and co-transfections in Drosophila SL2 cells. Furthermore, we identified two positive regulatory elements in the DNA region corresponding to the 5′-UTR (5′-untranslated region). The results in the present study indicate that Sp1 and Sp3 are required for constitutive NHE2 expression and that the positive regulatory elements of the 5′-UTR may co-operate with the 5′-flanking region to achieve the optimal promoter activity.
Understanding comorbidity between PTSD and substance use disorders: two preliminary investigations.

Abstract While there is high level of comorbidity of PTSD and substance use disorders (SUDs), little research has focused on the overlapping symptom constellation characteristic of both PTSD and substance use/withdrawal. This report describes two preliminary investigations that address this area. In the first study, the pattern of PTSD symptoms in a sample of women ( n = 28) seeking treatment for a SUD and comorbid with PTSD was compared with the symptom pattern of a sample of women ( n = 28) with PTSD only. The PTSD + SUD group evidenced significantly more symptoms in the avoidance and arousal symptom clusters than the PTSD-only group. At the individual symptom level, the PTSD + SUD group reported significantly more sleep disturbance than the PTSD-only group. It was also determined that the PTSD + SUD group reported greater traumatic-event exposure than the PTSD-only group. In the second study, PTSD symptoms were compared in a sample of alcohol- dependent and a sample of cocaine-dependent individuals with PTSD. The alcohol-dependent group exhibited significantly more arousal symptoms than the cocaine-dependent group. Implications of the results for the assessment of individuals with comorbid PTSD and SUDs are discussed.
Vacancy Migration Barrier Energetics and Pathways in Silica

A study of vacancy defect migration pathways and energetics in a-quartz is carried out using an empirical simulation methodology that is coupled with the nudged elastic band method. Results from this study indicate that the migration pathway for migration is between adjacent sites. We anticipate the results will guide modifications to empirical potentials for use in the study of point defect formation of more complex systems.
Trajectories of delinquency from age 14 to 23 in the National Longitudinal Survey of Youth sample

This study utilized data from the National Longitudinal Survey of Youth to investigate risk trajectories for delinquency and factors associated with different trajectories, particularly substance use. The sample (N = 8,984) was 49% female. A group-based trajectory model was applied, which identified four distinct trajectories for both males and females: (1) a High group with delinquency rates consistently higher than other groups, with some decrease across the age range; (2) a Decreased group, beginning at high levels with substantial decrease to near zero; (3) a Moderate group experiencing some decline but remaining at moderate rates of delinquency through most of the age range; and (4) a consistently Low group, having low rates of delinquency declining to near zero by mid- to late-teens. The Low group was distinguished by several protective factors, including higher rates of maternal authoritative parenting style, possible lower acculturation (higher rates of non-English spoken at home), higher rates of religious activity, later substance use initiation, lower rates of early delinquent activity, less early experience with neighborhood or personal violence, and higher rates of perceiving penalty for wrongdoing. Conversely, the High group was characterized by several vulnerability factors-essentially the converse of the protective factors above.
The Effect of Annealing on NiFe/FeMn Thin Film Couples

The antiferromagnctic FeMn thin film has been used to stabilize the domains in NiFe films by exchange-coupling, thus eliminating the Barkhauscn noise in magnetoresistive sensor designs. T'he strength of this exchange-coupling is highly dependent on the interfacial structure, as well as the interfacial composition of this NiFe/FeMn thin film couple. We have conducted isothermal, as well as isochronal anneals of NiFe/FeMn thin film couples, and monitored their magnetic properties, in particular the strength of their exchange-coupling. The strength of exchange-coupling, measured by the shift of the B-H loop obtained from a hysteresis loop tracer, increased monotonically with annealing time for isothermal anneals between 200 and 300 °C. At higher temperatures (up to 500°C), the interdiffusion between the two layers is so extensive that the NiFe layer loses its sort-magnetic properties and the coupling strength is degraded. Composition depth-profiling by scanning Auger analysis was conducted to study the interdiffusion profiles of the annealed samples. Cross-section transmission electron microscopy (XTEM) was used to study the microstructure, crystallography, and composition of these thin films after annealing. Micro-beam composition analysis was also carried out and the compositional profile obtained was compared to the Auger depth-profile results. Transmitted electron diffraction using selected area electron diffraction (SAED) and elongated probe micro-diffraction (EPMD) of XTEM samples was used to study the crystallography of these films.
Photostimulated field emission - image rounded barrier model

Abstract A theory of photostimulated field emission (PFE) is presented which is analogous to that of the surface effect in photoemission. We generalize and extend previous calculations of Bagchi and Taranko. Results are compared with data of Lee and Reifenberger. The theory does not yield the observed oscillatory dependence of the current as a function of applied field.
Azacytidine plus verapamil induces the differentiation of a newly characterized biphenotypic human myeloid-B lymphoid leukemic cell line BW-90

Abstract The biphenotypic cell line BW-90 was established from the peripheral blood of a a patient with a refractory acute myelomonocytic leukemia. All cells were HLADr + , CD34 − . Dual color flow cytometry showed simultaneous expression of myeloid (CD33) and B-lymphoid surface markers (CD19) on 60% of cells, CD54 on 91% of cells. Lymphoid lineage markers included CD20/CD22 coexpressed on 89% of cells, CD71 (70%), CD11a (48%), CD18 (54%), and surface lambda light chain (33%). Exposure to various cytokines individually and in combination for up to 14 days had no effect on cell proliferation or differentiation. Only long-term (10–14 days) exposure to 5637 cell-conditioned medium (CCM) induced growth inhibition and differentiation along the monocytic pathway. Differentiation-inducing agents retinoic acid (RA), dimethyl sulfoxide (DMSO) and phorbol 12-myristate 13-acetate (PMA) did not induce differentiation. Differentiation into the monocytic pathway was induced by 5-azacytidine (5AzaC) alone or in combination with verapamil (VP). The BW-90 cell line may serve as a model to study early steps of leukemogenesis and early hematopoiesis. It may provide insight leading to development of an effective therapy for treatment-resistant biphenotypic leukemias.
Exposure to the opioid antagonist naltrexone throughout gestation alters postnatal heart development.

The influence of endogenous opioid blockade by naltrexone during prenatal life on postnatal heart development was studied in rats. Pregnant Sprague-Dawley rats received daily injections of 50 mg/kg naltrexone (NTX) or saline throughout gestation; offspring were cross-fostered at birth to mothers not receiving NTX. In general, NTX-treated offspring weighed more than controls throughout preweaning life, whereas heart weights were often increased from age-matched controls up to 35 days. Biochemical analyses of nucleic acids and protein demonstrated that DNA and protein content were increased throughout development in NTX-treated animals relative to controls. Morphometric analyses revealed increases in total area of the heart and myocardial area in NTX-exposed rats relative to control levels. These data suggest that endogenous opioids function to regulate cardiac growth during the prenatal period, and that disruption of this process has long-term implication for cardiac biology.
Maternal depression and locus of control orientation as predictors of dyadic play behavior

Maternal locus of control orientation and depression were examined in relation to joint negotiation and coordination of mother-child play at 20 months. Subjects were 51 high-social-risk mothers and children. Mothers completed the I-E Scale and the Beck Depression Inventory prenatally and at 20 months; mother-child interaction was videotaped in a laboratory playroom at 20 months. Tapes were coded using the Control-Autonomy Balance Scales to evaluate maternal control and sensitivity and child engagement and autonomy. Analyses of dyadic play behavior indicated that maternal controllingness was related to an external locus of control orientation. Child engagement during play was related to the resolution of mild maternal depression. Les marques maternelles d'orientation contrǒle et la depression maternelle ont ete examinees en relation avec l'interaction commune et la coordination des jeux mere-enfant a 20 mois. Les sujets con-sistaient en 51 meres et enfants a haut risque social. Les meres completerent 1'Echelle I-E et l'Inventaire de Depression Beck prenatalement et a 20 mois; l'interaction mere-enfant fut filmee dans une salle de jeu laboratoire a 20 mois. Le cassettes video furent codees en utilisant les Echelles d'Equilibre Contriǒle-Autonomie. Le manque de contrǒle maternel durant le jeu etait lie a une adaptation dyadique marginale ou insuffisante. Les patterns en temps de depression maternelle et les marques de contrǒle etaient plus fortement lies au comportement de I'enfant qu'au comportement de la mere pendant la seance de jeu. En general, les profils psychologiques maternaux les moins optimaux etaient lies a des patterns plus negatifs d'adaptation de l'enfant a la mere pendant la seance de jeu.
Evaluation of the antitumor effects of Herpes simplex virus lacking ribonucleotide reductase in a murine retinoblastoma model.

Purpose. To determine if an attenuated herpes simplex virus (HSV) lacking the large subunit of ribonucleotide reductase has antitumor effects in a transgenic mouse model of retinoblastoma (LHβTAg). Methods. LHβTAg mice were injected ocularly with 1 × 106 pfu of the hrR3 virus and tumor sizes were measured 3 weeks later. Replication of the virus in the eye and cultured murine retinoblastoma cells was tested by titration. Distribution of the virus in tumor was measured by X-gal staining. Results. Intraocular injection of mice with hrR3 (n = 24) did not result in a significant reduction in tumor size compared to uninjected (n = 24) or PBS injected controls (n = 16). Neither the hrR3, nor the HSV RE6 mutant, which was previously shown to have antitumor effects in vivo, replicated in cultured murine tumor cells in vitro, compared to wild-type HSV. The hrR3 virus also did not replicate significantly in tumor cells in vivo, compared to normal eye tissue. Conclusions. These results suggest that mutant HSV lacking...
Dislocation motion in high strain-rate deformation

We present a systematic investigation of dislocation motion, dislocation interactions, and the collective behaviour of dislocations in high strain-rate deformation. Based on results from three-dimensional dislocation dynamics simulations, we find that employing the accurate, full-dynamics, equation of motion (i.e. that includes inertial effects) significantly changes the predictions of microstructural evolution and the macroscopic response compared to the commonly used overdamped equation of motion (i.e. with no inertial effects), especially at high strain rates (103–106 s−1). While we find that inertial effects cannot be neglected, the net velocities are not high enough that ‘relativistic’ effects are important. We also present results on the effects of high strain rates on single-crystal deformation, which show good agreement with experimental trends, including increased hardening with increasing strain rate.
Some ethical issues in toxicology.

Abstract In May 1984 all Society of Toxicology (SOT) members having U.S. mailing addresses received a questionnaire concerning potential ethical problems in the practice of toxicology. This letter is to report on the results of that survey. As a preliminary matter it should be understood that the term ethics is being used to signify nothing more than a set of rules of behavior; it is in no way meant to be prescriptive. There are, in this sense, many types of ethical rules ( Frankena, 1973 ). Table 1 lists some examples of ethical rules. As can be seen, ethical rules can vary depending on the situation in which the individual is acting. The rules listed in Table 1 obviously are merely examples of some of the many rules that all of us as individuals follow at various times and in different situations. Ethical issues arise when two or more of the rules which an individual follows come into conflict. At that time a decision has to be made by the individual as to which of the rules will receive priority, i.e., which rules are more important than which other rules. The survey involved in this study was designed to get some rough idea of the rules given precedence by members of the Society of Toxicology.
Polymer Melting Kinetics Appears to be Driven by Heterogeneous Nucleation

A recently proposed method is used to parameterize the nucleation-driven kinetics of poly(e-caprolactone) melting. The method is based on fitting a theoretically derived temperature dependence of the effective activation energy to the experimental dependence obtained from the Kissinger plot. Although the theoretical dependence fits the experimental one accurately, the fit gives rise to a surface free energy that is significantly smaller than the one obtained from crystallization data. A similar result is reported in other publications that make use of a homogeneous nucleation model for poly­mer melting. It is argued that a heterogeneous nucleation model is a more appropriate representation of the melting process and that its use resolves the problem of estimating the unusually small surface free energies.
Asymptotic equidistribution of congruence classes with respect to the convolution iterates of a probability vector

Abstract Consider a positive integer d and a positive probability vector f over the numbers 0 , … , l . The n -fold convolution f ∗ n of f is a probability vector over the numbers 0 , … , n l , and these can be partitioned into congruence classes modulo d . The main result of this paper is that, asymptotically in n , these d congruence classes have equiprobability 1 / d . In the motivating application, one has N containers of capacity d and repeatedly retrieves one item from each of M randomly selected containers ( 0 M N ); containers are replenished to full capacity when emptied. The result implies that, over the long term, the number of containers requiring replenishment is M / d . This finding is relevant wherever one would be interested in the steady-state pace of replenishing fixed-capacity containers.
End Stage Heart Failure: Cardiologists’ Reluctance To Discuss End of Life Care

Purpose Advanced heart failure (HF) patients suffer from significant symptoms and complicated end of life (EOL) issues. There are documented studies that demonstrate increased survival for patients receiving hospice; however, hospice remains under-utilized and EOL discussions are delayed. We hypothesized that cardiologists do not integrate EOL care into their treatment algorithm in HF because they believe that it is not within their scope of practice. Methods and Materials IRB approval and permission from Dr. Paul Hauptman to use his survey of clinical practice in HF was obtained. This survey was sent electronically to all providers in the Division of Cardiology including faculty members, nurse practitioners, and fellows in training. Results Of 55 initial surveys taken, 38 surveys were complete. 66% of respondents believed that end stage HF patients experience moderate, severe, or extreme pain. All practitioners believed that patients experienced moderate, severe, or extreme dyspnea in end-stage HF. Of those individuals with worsening symptoms despite optimal medical therapy, 63% of care providers reported referring to palliative care often or always, and 37% sometimes or never. 89% agreed that cardiologists should initiate discussions about end of life care while only 11% believed that primary care providers should do so. Of 36 respondents who commented on their willingness to refer to hospice, 58% believed that the timing of the referral was a concern. 47% were concerned that the offer would not be accepted. 14% were unsure whether hospice referrals were within the scope of their cardiology practice. Conclusions Despite practitioners’ belief that patients with end stage HF have severe symptoms and that cardiologists should initiate EOL care discussions, almost half of respondents were unsure when to refer to hospice and whether it would be accepted. We believe that further education addressing the timing of EOL discussions and potential benefits of hospice would improve quality of care for the HF population.