cssi/SciSciGPT-SciSciNet huggingface dataset:
0.33-k1 ArF lithography for 100-nm DRAM

We have evaluated 0.33k1 ArF lithography using 0.63NA scanner to develop 100 nm DRAM. ArF resist problems were resist pattern shrinkage during CD SEM measurement, resist pattern collapse during wet development and poor etch resistance. Off-Site Measurement (OSM) method has been developed for decreasing pattern shrinkage. With OSM method, 8nm of CD shrinkage was down to 2nm for 100nm L/S patterns. We have found a proper BARC material that prevents resist patterns falling down. Lack of etch resistance was compensated by hard mask. With W/SiN hard mask, acrylate- type resist patterns were transferred well into W/poly-Si gate patterns. We have simulated process window of critical DRAM cell patterns (isolation, gate, bit line contact, storage node) in the simple off-axis illumination (OAI) and optical proximity correction (OPC) conditions based on single exposure. Simulation results were verified by lithography tests and it turned out that 0.33k1 process was possible with exposure latitude of above 10% and focus latitude of more than 0.4 micrometers . 0.33k1 ArF lithography was successfully implemented into 100 nm DRAM with CD uniformity of 10nm (3 (sigma) ) and overlay accuracy of 30 nm (mean +3 (sigma) ). We have also evaluated double exposure technique using dipole illumination targeting 90 nm in order to see the possibility of 0.29k1 process. 0.29k1 process was also likely to be possible, although some specific improvements were recommended for the wider process window. From the simulation and resist patterning results, we believe that 0.85 NA lens will be able to extend ArF lithography into 75 nm by single exposure technology using crosspole illumination (0.33k1 process) and 65 nm by double exposure technology using dipole and crosspole illumination (0.29k1 process).
Acetylcholine receptor fiber-optic evanescent fluorosensor.

An acetylcholine receptor-based optical biosensor was developed, which uses the evanescent wave to excite fluorescein isothiocyanate-labeled alpha-bungarotoxin (FITC-alpha-BGT), that is bound to a receptor protein immobilized on the surface of a quartz fiber. After excitation of the fluorophore just outside the waveguide boundary, the resultant fluorescence was trapped by and propagated back up the fiber. Pure nicotinic acetylcholine receptor (nAChR) protein, isolated from Torpedo electric organ, was immobilized noncovalently on quartz optic fibers and its density was quantitated by 125I-BGT binding. In the absence of nAChR, FITC-alpha-BGT alone bound to the quartz fiber. This nonspecific (i.e., nonreceptor) binding of FITC-alpha-BGT was totally eliminated by the addition of 0.1 mg/ml bovine serum albumin to the phosphate-buffered saline medium. This solution did not interfere with FITC-alpha-BGT binding to the nAChR that was immobilized on the fiber. Thus, only specific binding was observed under these conditions, resulting in a very high signal-to-noise ratio of greater than 99. Specific FITC-alpha-BGT binding to the nAChR protein on the optic fibers was inhibited by agonists (e.g., acetylcholine, nicotine, and carbamylcholine) and antagonists (e.g., pancuronium and d-tubocurarine) of the nAChR and was insensitive to high salt concentrations (e.g., 154 mM NaCl). The binding was most sensitive to the highly nAChR-specific alpha-BGT and alpha-cobratoxin. The optic-fiber sensor in its present form does not distinguish between receptor agonists or antagonist and cannot be regenerated for repeated use.(ABSTRACT TRUNCATED AT 250 WORDS)
Infrared matrix-assisted laser desorption/ionization of polycyclic aromatic hydrocarbons with a sulfolane matrix.

Infrared matrix-assisted laser desorption/ionization (IR-MALDI) of the polyaromatic hydrocarbons (PAHs) anthracene, benzo[a]pyrene, and dibenz[a,h]anthracene was performed using a 10.6-µm CO2 laser and a liquid matrix. Sulfolane (tetrahydrothiophene 1,1-dioxide) was found to be an effective matrix for PAH ionization: mass spectra obtained with a sulfolane matrix contain an intense molecular ion peak; interference from PAH fragment and matrix peaks is negligible in all cases. The main limitation of the sulfolane matrix is sample evaporation after 3 to 5 min in vacuum. This sample lifetime can be increased to between 15 and 30 min using a 2:1 (v/v) mixture of sulfolane and glycerol, but the resulting spectra have greater matrix interference and decreased shot-to-shot signal stability. Copyright © 2001 John Wiley & Sons, Ltd.
Immunotyping of radial glia and their glial derivatives during development of the rat spinal cord

The differentiation of glia in the central nervous system is not well understood. A major problem is the absence of an objective identification system for involved cells, particularly the early-appearing radial glia. The intermediate filament structural proteins vimentin and glial fibrillary acidic protein have been used to define the early and late stages, respectively, of astrocyte development. However, because of the non-specificity of vimentin and the temporal overlap in expression patterns of both proteins, it is difficult to refine our view of the process. This is especially true of the early differentiation events involving radial glia. Using the developmentally-expressed intermediate filament-associated protein IFAP-70/280 kD in conjunction with vimentin and glial fibrillary acidic protein markers, a comprehensive investigation of this problem was undertaken using immunofluorescence microscopy of developing rat spinal cord (E13-P28 plus adult). The phenotypes of the cells were defined on the basis of their immunologic composition with respect to IFAP-70/280 kD (I), vimentin (V) and GFAP (G). A definitive immunotype for radial glia was established, viz, I+/V+/G-; thus reliance upon strictly morphological criteria for this early developmental cell was no longer necessary. Based upon the immunotypes of the cells involved, four major stages of macroglial development were delineated: (1) radial glia (I+/V+/G-); (2) macroglial progenitors (I+/V+/G+); (3) immature macroglia (I-/V+/G+); and (4) mature astrocytes (I-/V+/G+ primarily in white matter and I-/V-/G+, the predominant type in gray matter). It is of interest to note that the cells of the floor plate were distinguished from radial glia by their lack of IFAP-70/280 kD immunoreactivity. Introduction of the IFAP-70/280 kD marker has therefore provided a more refined interpretation of the various differentiation stages from radial glia to mature astrocytes.
Towards a better capstone experience

The computer science capstone experience is designed to bridge the gap from university expectations to those of industry. Yet trying to solve this problem with a single course sequence, even one spanning the senior year, has some shortcomings, in terms of learning outcomes which can be achieved, and also instructional strategies that can be employed. We describe here an alternative plan which first provides a junior year of practice on a client-based project integrated with learning design and other related topics, followed by a senior year in which students can work more independently to hone these skills on a harder year-long project with another client. This two-year sequence, with scaffolding provided at first that is gradually removed, has proven to be especially effective in preparing undergraduates for a career in the soft- ware industry. The approach also integrates well with the need for these students to become proficient at working in engineering teams.
SOME COMMONLY OVERLOOKED PROPERTIES OF CALCIUM BUFFER SYSTEMS : A SIMPLE METHOD FOR DETECTING AND CORRECTING STOICHIOMETRIC IMBALANCE IN CAEGTA STOCK SOLUTIONS

When the two-solution approach is used to make CaEGTA buffers, the most critical requirement is that the CaEGTA stock solution contain equimolar quantities of calcium and chelator. The impact on [Ca2+] of errors in the molar ratio is magnified at high buffer ratios, so stoichiometric imbalance is most readily detected there. In this paper we examine some of the properties of calcium buffer systems that illustrate these principles, and describe a simple and sensitive method for detecting and correcting stoichiometric imbalance in the CaEGTA stock solution. The method derives its high sensitivity from the fact that the CaEGTA stock solution itself represents a calcium buffer system with a very high buffer ratio.
Effects of rotational infrastructure within pasture-raised pig operations on ground cover, soil nutrient distribution, and bulk density

Interest in pasture-based pork products has increased significantly in recent years. However, nitrogen (N) losses resulting from these systems are common due to importation of feed, high stocking rates, and pig behavior. This study was conducted to evaluate soil inorganic N, soil-test phosphorus (STP), ground cover, and compaction changes as impacted by rotational shade, water, and feed structures in a pasture-raised pig operation over two 12-week pig occupations. Shade and watering structures were rotated weekly for 12 weeks within a rotational (mobile) scheme; data were compared to a stationary structure system as well as to a managed hay operation with no pigs. Soil samples were acquired from subplots and analyzed for distribution of inorganic N concentrations among main plot treatments, including nitrate (NO3), ammonium (NH4), and STP values. Soil inorganic N concentrations were higher in exterior subplot positions than in interior positions. This pattern was not maintained after a second pig group occupied the plots. Soil test phosphorus was unaffected by either pig occupation. Ground cover percentages were higher in control (hay) treatments than for pig treatments, however no difference was found between mobile and stationary structure treatments in either pig occupation. Soil compaction, as measured by soil bulk density, was found to be higher under permanent shade structure locations as compared to mobile and control treatments. Mobile and control compaction levels were not different for the second occupation, utilizing a more intensive sampling scheme, suggesting a benefit to the rotation of shade, water and feed infrastructure. The weekly rotation of infrastructure performed during both occupations was both labor intensive and time consuming. The observed lack of improvement in nutrient distribution to a rotational infrastructure may limit its utility in pastured-pig systems. However, further options are available that would allow the production of pasture-raised pigs while minimizing associated nutrient loading and pasture degradation.
Balloon expandable intravascular stents: Aortic implantation and late further dilation in growing minipigs

Abstract Intravascular stents have been implanted in children with congenital and acquired vascular stenoses. Little information is known regarding the long-term results in growing patients, the implantation of multiple stents (in series), and the feasibility of further dilation. Nine stents were implanted in the abdominal aortas of 6 mini-pigs; in 3 pigs, 2 stents were implanted in series. Five pigs were recatheterized 196 ± 17 days after stent implant. All stents were patent, with mild narrowing at the stent relative to the adjacent aorta; further stent dilation was performed. The stent diameter increased from 8.3 ± 0.6 mm to 11.2 ± 1.3 mm ( p = 0.002), and the narrowing was relieved. These five pigs were catheterized 253 ± 73 days after stent redilation. Each stent was patent without narrowing or pressure gradient. We conclude that intravascular stents do not interfere with normal growth, can be implanted in series, and can be further dilated.
PROMISES AND PERILS OF MANAGED CARE FOR OLDER PATIENTS WITH CARDIAC DISEASE

Managed care in the United States is evolving rapidly and currently presents a complex mosaic of administrative and clinical practices that show considerable regional variation. The concept of managed care has existed for many years, but until recently older patients with chronic conditions, such as cardiovascular disease, have not been sought after by managed care organizations. This situation is hardly surprising because such patients account for a disproportionate share of health care costs and could endanger the profitability of any enterprise that assumes their care for a preset fee. The success of managed care in moderating health care spending among the employed and societal and political pressures to control the growth of Medicare costs, however, have led to the expansion of managed care options for older populations. This article represents only a snapshot of a huge moving picture and is, of necessity, incomplete because experience in this population is limited. For purposes of this article, managed care is defined as a system to structure critical aspects of the delivery of care in a way that controls cost, while maintaining or improving the quality of care. Even within such a simple definition, a wide variety of models may exist, with varying degrees of control over provider behaviors that influence costs and outcomes of care. The promise of managed care lies in the use of strategies that provide maximal health care value, which can be defined as the optimal tradeoff of technical quality, functional outcomes, costs, access to care, and patient and provider satisfaction. The perils, however, are the facts that health care value is not easily assessed and that short-term marketplace success may depend on selection of healthier patients and denial of complex but necessary care. For older patients with cardiac disease, these promises and perils are critically important because these patients have more to gain from improved systems of care, yet are more likely to suffer if their needs are not met.
Metformin impairs the growth of liver kinase B1-intact cervical cancer cells.

Objective Metformin is one of the most widely used drugs for the treatment of type 2 diabetes. Recent investigations demonstrated that application of metformin reduces cancer risk. The present study aimed to determine the role of liver kinase B1 (LKB1) in the response of cervical cancer cells to metformin.
Offshore outsourcing and political risk: India in 2004

The results of the 2004 Indian elections were surprising as the victory of the Congress party was unforeseen by most pre-poll and exit surveys. The unexpected political change, with an associated shift from a centre-right to a centre-left government presented an unanticipated discontinuity in the business environment. We examine whether US companies that had offshored to India faced heightened levels of political risk when election results were announced. A unique contribution of the paper is that we also examine whether US companies that offshored to India in early-2004, faced greater political risk than companies that offshored to the country in 2002 and 2003. Results indicate an increase in political risk as manifested as an increase in systematic risk. Companies that offshored in 2004 faced greater political risk as compared to companies that offshored earlier. Our findings validate the use of a political risk premium when evaluating offshore ITES projects.
Isolation and biochemical characterization of brush borders from rabbit kidney.

A technique for the isolation of intact brush borders from rabbit renal cortex was evaluated. The procedure was monitored by phase and electron microscopy and marker enzymes, i.e. ATP:NMN adenylyl transferase, nuclear; cytochrome oxidase, mitochondrial; beta-glucuronidase, lysosomal; and glucose-6-Pase, microsomal; and indicated an essentially pure preparation of brush borders. The disaccharidase, trehalase, previously reported in renal tubules, was localized uniquely in brush borders. Maltase was also found; the specific activities of the two enzymes in the brush borders were increased 10- to 20-fold. Other disaccharidases, such as sucrase, isomaltase, lactase, and cellobiase, were absent. It is suggested that trehalase and maltase are appropriate candidates for marker enzymes of the renal brush border. Isolated brush borders possessed a ouabain-sensitive (Na(+) + K(+)) ATPase, an oligomycin-insensitive Mg(++) ATPase, and a Ca(++)-activated ATPase. Alkaline phosphatases, dephosphorylating beta-glycero-P, and trehalose-6-P were also present. The specific activities of these enzymes were increased three-to-five fold in the brush-border preparations; however, activities were found in other subcellular fractions of the renal cortex. Hexokinase, although evident in the isolated brush border, was found prominently associated with other membranous fractions. Phosphoglucomutase and UDPG pyrophosphorylase were localized in the soluble fraction of the renal cortex.
Introduction: centrally acting agents in male sexual dysfunction.

This supplement delves into central nervous system (CNS) aspects of male sexual dysfunction. Our understanding of the role of the CNS in potentiating sexual behavior is progressing rapidly. However, we are still in the early phases of research to determine if CNS-acting agents can be used to help treat various types of sexual dysfunction.
Water uptake in to polyanhydride devices: kinetics of uptake and effects of model compounds incorporated, and device geometry on water uptake

Polyanhydrides are known as surface eroding biodegradable polymers since they are hydrophobic, which is believed to prevent penetration of water into the bulk and hence only the labile bonds on the surface are hydrolyzed. We wanted to test the hypothesis that polyanhydrides, specifically poly(fatty acid dimer-sebacic acid; FAD-SA) undergo pure surface erosion. If P(FAD-SA) does indeed undergo pure surface erosion, very little water should be present in the device since the polymer is hydrophobic and hydrolyzed on contact with water. An understanding of water uptake is also necessary to predict the stability and release of the incorporated drug. The specific aims of this study were to establish the rate of water uptake into P(FAD-SA) devices of cylinder and disk shapes at various pH conditions, and to study the effect of loaded model drug compounds (having different molecular size, aqueous solubility and dissolution rate) on water uptake. The model compounds included: mannitol, inulin and stearic acid, loaded at 10% (w/w) in disk-shaped devices. Water uptake was estimated from the amount of tritiated water found in the devices after they were soaked and gently mixed with buffers (pH 1–9) containing tritiated water (1 μCi/ml) at various time intervals. The results showed that water uptake by the device is a function of pH (pH 9 > pH 7.4 ⋙ pH 1–5). Significantly higher amount of water was taken up at pH 7.4 and 9.0 (8–9% (v/v) for cylindrical devices, 15–25% (v/v) for disk-shaped device in 2 weeks), compared to less than 5% (v/v) uptake between pH 1 and 5. Disk-shaped devices showed a faster uptake rate compared to cylinder-shaped devices due to their higher surface area to volume ratio. The loaded compounds had no significant effect on either the water uptake profile or water uptake kinetics at all pH values examined. From the large amount of water (up to 20% (v/v)) found in the devices at pH 7.4 and pH 9.0, it appears that P(FAD-SA) does not undergo pure surface erosion. The photomicrographs of the devices at various stages of water uptake showed channels on the rough surface indicative of bulk erosion rather than pure surface erosion.
Use of preventive health behaviors by lesbian, bisexual, and heterosexual women: questionnaire survey.

Objectives To determine whether lesbians and bisexual women are less likely than heterosexual women to use preventive health measures. Design Written, anonymous, self-administered questionnaire. Setting 33 physicians' offices and community clinics mainly in urban areas of 13 states. Participants 524 lesbians, 143 bisexual women, and 637 heterosexual women. Results Bisexual women were less likely than heterosexual women to have had appropriate cholesterol screening (odds ratio 0.29, 95% confidence interval 0.11 to 0.73) or appropriate mammography (0.33, 0.13 to 0.84). Human immunodeficiency virus testing was more common in lesbians (2.38, 1.51 to 3.74) and bisexual women (1.99, 1.17 to 3.38) than in heterosexual women. Illicit drug use was higher in lesbians (2.04, 1.14 to 3.70) and bisexual women (1.96, 1.07 to 3.57) than in heterosexual women. Lesbians were more likely than heterosexual women to practice safer sex (2.60, 1.23 to 5.49) and less likely to have ever been infected with human papillomavirus (0.48, 0.25 to 0.89). Conclusion There were important differences in the preventive health measures taken by lesbians and bisexual women and those taken by heterosexual women. All patients should receive standard health tests, such as cholesterol screening and mammography, regardless of their sexual orientation. Lesbians and bisexual women who report illicit drug use should receive counseling, as appropriate.
Correlation of serum immunoglobulin subclass concentrations with antibody responses of children to immunization with Haemophilus influenzae type b polysaccharide-pertussis vaccine.

Children less than 24 months of age respond poorly to immunization with the capsular polysaccharide ofHaemophilus influenzae type b. Because human antibodies to polysaccharide antigens are relatively restricted to IgG2, a late-maturing subclass, we examined the relationship between serum subclass concentrations and anticapsular antibody responses of 41 healthy children, 9 to 38 months of age, following immunization with type b polysaccharide mixed with pertussis vaccine. Both total and IgG anticapsular antibody responses correlated significantly with preimmune serum concentrations of IgG2 but not with those if IgG1. This correlation was age dependent, however, and after the effect of age was removed by partial correlation, the correlation between anticapsular antibody responses and serum IgG2 concentrations was no longer significant. These findings indicate that the ability to respond to this vaccine coincides with maturation of the ability to secrete immunoglobulin of the IgG2 subclass; however, individual variation in IgG2 that is independent of age does not correlate with antibody response to the type b polysaccharide.
Long term stability of a recombinant Plasmodium falciparum AMA1 malaria vaccine adjuvanted with Montanide(®) ISA 720 and stabilized with glycine.

Abstract Plasmodium falciparum apical membrane antigen 1 (AMA1) is an asexual blood-stage vaccine candidate against the malaria parasite. AMA1-C1/ISA720 refers to a mixture of recombinant AMA1 proteins representing the FVO and 3D7 alleles in 1:1 mass ratio, formulated with Montanide ® ISA 720 as a water-in oil emulsion. In order to develop the AMA1-C1/ISA720 vaccine for human use, it was important to determine the shelf life of this formulation. Previously it was found 267 mM glycine stabilized the proteins in Montanide ® ISA 720 formulations for a short period of time at 2–8 °C [25] . We now test the long term stability of AMA1-C1 at 10 and 40 μg/mL formulated with Montanide ® ISA 720 with 50 mM glycine as a stabilizer. Stability of AMA1-C1/ISA720 at different time points following formulation (0, 5, 12 or 18 months) was evaluated by determining the mean particle size (diameter of the mean droplet volume), total protein content by a Modified Lowry assay, identity and integrity using western blot and SDS–PAGE. Our results showed that the mean particle size of these emulsions increased over time, whereas protein content, as determined by an ELISA method using a monoclonal antibody against penta-his, decreased over time. For the 10 μg/mL AMA1-C1/ISA720 vaccine, the protein content was 6.5 ± 2.2 μg/mL, and for the 40 μg/mL AMA1-C1/ISA720 vaccine, the protein content was only 8.2 ± 2.3 μg/mL after 18 months of storage at 2–8 °C. These results suggest that the integrity of the protein was affected by long-term storage. The results of the present study indicate that the AMA1-C1/ISA720 emulsion was unstable after 12 months of storage, after which AMA1-C1 proteins were partially degraded.
Nonlinear Effects of Coexisting Surface and Atmospheric Forcing of Anthropogenic Absorbing Aerosols: Impact on the South Asian Monsoon Onset

AbstractThe direct radiative effect of absorbing aerosols consists of absorption-induced atmospheric heating together with scattering- and absorption-induced surface cooling. It is thus important to understand whether some of the reported climate impacts of anthropogenic absorbing aerosols are mainly due to the coexistence of these two opposite effects and to what extent the nonlinearity raised from such coexistence would become a critical factor. To answer these questions specifically regarding the South Asia summer monsoon with focus on aerosol-induced changes in monsoon onset, a set of century-long simulations using the Community Earth System Model, version 1.0.3 (CESM 1.0.3), of NCAR with fully coupled atmosphere and ocean components was conducted. Prescribed direct heating to the atmosphere and cooling to the surface were applied in the simulations over the Indian subcontinent, either alone or combined, during the aerosol-laden months of May and June. Over many places in the Indian subcontinent, the ...
Education for Environmental Protection: Successes, Challenges, and Opportunities for USEPA's Environmental Education Program

We are moving beyond a time when we can rely on a cadre of environmental experts to fix our environmental problems.… A stronger public understanding of environmental science and related issues is a...
Remodeling human cortex through training: comment on May.

In his recent review, May [1] highlights longitudinal adult human magnetic resonance imaging (MRI) studies reporting gray and white matter changes with short-term training. As May notes, these longitudinal, compared with cross-sectional, studies potentially provide the strongest evidence for the causal effect of training on adult brain structure. However, both the robustness and interpretation of these results deserve careful consideration.
The effect of maternal partial exchange transfusion on the infants of patients with sickle cell anemia

The reproductive outcome of pregnancies complicated by severe sickle cell hemoglobinopathies is not usually satisfactory. In this study, prophylactic partial exchange transfusions have been used in 35 patients with sickle hemoglobinopathies. There was significant improvement in results, both maternal and neonatal, as compared to those in 29 pregnancies complicated by similar disease processes who did not receive this therapy. The former group was also compared to 61 normal pregnant patients and 31 patients with sickle cell trait, none of whom received blood as part of their therapy. The results were similar in the group receiving transfusions and in the group with sickle cell trait. There was a decrease in perinatal wastage, prematurity, and incidence of low-birth-weight infants in the transfusion group when compared to the patients with hemoglobinopathies who were treated conservatively.
Rats become acutely tolerant to cathine after amphetamine or cathinone administration.

The drug discrimination paradigm was used to evaluate in rats the ability of the discriminate response to either 0.8 mg/kgd-amphetamine or 0.8 mg/kgl-cathinone to generalize to 2.4–6.0 mg/kg of the active cathinone metabolited-norpseudoephedrine, also known as cathine. When tested 24 h after vehicle administration, cathine generalized in a dose-related fashion in rats (n=6) trained with cathinone (ED50=3.03 mg/kg) and in rats (n=8) trained with amphetamine (ED50=2.93 mg/kg). In contrast, when cathine was tested 24 h after the administration of either amphetamine or cathinone, it produced significantly decreased discriminative performance. The possibility that this acute tolerance may have been produced by release, and subsequent depletion, of brain dopamine was tested by pretreating rats with the dopamine release inhibitor CGS 10746B. When CGS 10746B was administered prior to cathinone it significantly decreased cathinone discrimination. In addition, acute tolerance to cathine at 24 h after vehicle-cathinone co-administration was reversed when cathine was tested 24 h after CGS 10746B-cathinone co-administration. The results suggest that cathinone-produced discriminative stimulus, as well as the acute tolerance to cathine, may be dopaminergically mediated.
Pseudomigraine With Prolonged Aphasia in a Child With Cranial Irradiation for Medulloblastoma

We report a 12-year-old child with episodes of migraine-like headaches with visual and motor auras a year after the surgical resection and radiation therapy for medulloblastoma. The patient presented with an episode of headache, prolonged aphasia, right hemiparesis, status epilepticus, and salt wasting. There was no evidence of a structural lesion. The neurologic deficits resolved over a period of 6 weeks. Because of the progressive deterioration in neurologic deficits, the patient underwent an extensive battery of laboratory tests and multiple neuroimages, all of which were normal. The unusually prolonged neurologic deficit in this patient without demonstrable structural lesions and his eventual complete recovery were most likely caused by ischemia in the left hemisphere secondary to vasospasm. This presentation mimics migraine headache. Evidence suggesting that this represents a long-term complication of treatment of children with central nervous system neoplasia is presented. (J Child Neurol 2002;17:13...
Liquid and gas chromatographic analyses of several fossil proteins

Abstract 1. 1. Comparative liquid column and gas chromatographic analyses have been made of residual proteins extracted from fossil shells of ages up through the Cretaceous. 2. 2. They demonstrate that after a preliminary resin column clean-up of hydrolysates for the gas chromatography, results obtained by the two techniques are in excellent agreement. 3. 3. The gas analytical procedure requires 1/30 to 1/50 as much protein as the other and this substantially enlarges the range of fossils that can be successfully analyzed.
Variation in the tissue water relations of two sympatric Hawaiian Dubautia species and their natural hybrid.

At one site of sympatry on the Island of Hawaii, Dubautia ciliolata and D. scabra are restricted to different lava flows, even though individuals of the two species may be found growing within a few meters of one another. Associated with this habitat difference is a difference in the tissue water deficits experienced by these two species. Midday water potentials in D. ciliolata are typically 0.4–0.5 MPa lower than in D. scabra.
Determination of phosphorus in steel with a stabilized-temperature graphite furnace and zeeman-corrected atomic absorption spectrometry

Abstract The determination of phosphorus in steel by graphite furnace a.a.s. is plagued by a spectral interference from the iron matrix which results in overcompensation when a continuum-source background corrector is used. Zeeman background correction using an alternating transverse magnetic field at the furnace eliminates this problem and allows a routine determination of phosphorus down to 0.002% in steel. Lanthanum is an effective matrix modifier for the phosphorus determination, but its enhancing effect depends largely upon the tube material used and the sample matrix. A 0.2% lanthanum solution was found to be optimum. The stabilized-temperature platform furnace concept allows an interference-free determination of phosphorus in steel, down to 0.002%, directly against aqueous standards. Atomizing the sample from a pyrolytic graphite platform in an uncoated graphite tube provides the optimum environment for a phosphorus determination.
Vibrational frequency distribution for nonconservative model of double-walled carbon nanotube

The paper presents the mathematical results for a double-walled carbon nanotube model with nonconservative boundary conditions, given in the form of two Timoshenko beams coupled through a distributed Van Der Waals force. The system is clamped at the left end and subject to a four-parameter family of dynamical boundary conditions at the right end. We also present the four-branch vibrational spectrum of the system. All the results are purely analytical; they will be complemented by numerical simulations in a forthcoming work.
Preschoolers' fantasy-reality distinctions of emotional events.

Abstract Research suggests that emotions influence children’s ability to discern fantasy from reality; however, reasons for this association remain unknown. The current research sought to better understand the mechanisms underlying children’s distinctions by examining the roles discrete emotions and context have in 3- to 5-year-olds’ evaluations of fantasy and reality. In Study 1, children’s fantasy–reality distinctions of images depicting happy, frightening, or sad events were obtained under two conditions: Children responded freely or were motivated to respond accurately. When responding freely, older children reported that happy and sad fantastic and real events could occur but frightening events could not. When motivated to respond accurately, children’s accuracy improved for fantasy but not for reality. Study 2 examined real events exclusively and found that children may lack the knowledge that frightening, but not happy or sad, real events can occur. The findings provide new insight into how emotions affect children’s fantasy–reality distinctions.
Angular Dependence for ν‘, j‘-Resolved States in F + H2 → HF(ν‘, j‘) + H Reactive Scattering Using a New Atomic Fluorine Beam Source

Angular distributions are measured for individually resolved ν‘, j‘ states of HF produced by F + H2 → HF(ν‘ = 1, j‘) + H and F + H2 → HF(ν‘=2, j‘) + H reactive collisions in a crossed-beams scattering apparatus. Simultaneous resolution of the HF vibrational and rotational states is achieved spectroscopically for the first time, using laser excitation in conjunction with bolometric detection. The technique is sensitive to population differences between ν‘ = 1, j‘ and ν‘ = 2, j‘ − 1 states optically coupled by specific P2(j‘) lines of a vib-rotational chemical laser. The measurements are greatly facilitated by the development of a new high-temperature atomic fluorine beam source, which exhibits excellent stability, very high intensity, and narrow velocity distributions. Features common to individual product rotational states are as follows: strong backward scattering into ν‘ = 2, j‘; weaker backward scattering into ν‘ = 1, j‘; and heretofore unobserved scattering into ν‘ = 1, j‘ in the forward hemisphere. ...
Superficial Femoral Vein Graft Interposition In Situ Repair for Femoral Mycotic Aneurysm

Femoral mycotic aneurysms require surgical treatment to prevent progressive sepsis and hemorrhage. Some surgeons recommend simple debridement and ligation of the femoral artery, whereas others recommend reconstruction in selected cases or all cases due to concerns about high risk of limb loss. In situ reconstruction has been discouraged due to concerns about anastomotic or graft disruption by persistent infection. However, the superficial femoral vein has been used successfully as an in situ replacement after removal of infected aortic prostheses. We present two patients with femoral mycotic aneurysms, both of whom were treated successfully with in situ reconstruction using autogenous superficial femoral vein.
The Role of Poverty and Chaos in the Development of Task Persistence Among Adolescents

Late adolescents (N = 256; Mage = 17.5) who spent a larger proportion of their early life in poverty exhibited less persistence when confronted by a challenging task. Greater chaos during early adolescence also predicted less task persistence at age 17. However, the effects of poverty were moderated by chaos such that if chaos levels were high during early adolescence, task persistence was uniformly lower among late adolescents, irrespective of childhood poverty. Only when chaos levels were relatively low did poverty matter for future task persistence. Furthermore, the interactive effects of chaos and early childhood poverty were independent of child ability, and of concurrent chaos and poverty.
Effects and Interactions of Environmental Chemicals on Human Cells in Tissue Culture

The toxicity of environmental chemicals was determined using HeLa cells and human skin fibroblasts. Aspirin, caffeine, a polychlorinated biphenyl plasticizer, carbaryl, parathion, DDT, and several insecticide metabolites were studied. The dosage causing a 50% inhibition in culture growth was determined and the interaction between these chemicals and their effect on protein and nucleic acid synthesis was determined. Both cell types responded nearly equally to the presence of an individual chemical. Aspirin and caffeine were 8 to 20 times less toxic than the other chemicals studied, while the plasticizer was as toxic as DDT. Parathion was more toxic than its metabolite para- oxon. Para-nitrophenol was as toxic as parathion. 1-Naphthol was less toxic than its parent compound carbaryl. The toxicities of DDT and DDE were dependent upon cell type. Little significant interaction on nucleic acid or protein synthesis was seen.
Photoemission Studies of Copper and Silver: Theory

Theoretical expressions are derived for the quantum yield and for the energy distribution of photoelectrons assuming bulk photoemission from a solid. The effects of electrons which escape without inelastic scattering after optical excitation, and of those electrons which escape after one inelastic-scattering event, are considered. The expressions relate optical transition probabilities, optical constants, and mean free paths for inelastic scattering in a solid to quantities which can be measured in photoemission experiments. Examples of photoemission data are interpreted to show how the contribution of once-scattered electrons can be separated from the contribution of those electrons which have not suffered an inelastic-scattering event before escaping. The contribution to photoemission of those electrons which have not been scattered is analyzed to show the way in which direct and nondirect optical transitions can be identified and the way in which the density of states in a solid can be determined. The contribution of once-scattered electrons to photoemission is analyzed to show the way in which the nature and strength of inelastic-scattering mechanisms can be determined. The effects of electron-electron scattering, scattering by plasmon creation, and the Auger process are described, and methods of obtaining mean free paths and other scattering parameters are suggested.
Particle transfer from a continuous oil to a dispersed water phase: Model particle study

The surface free energy of glass microbeads was controlled by varying the extent of reaction between t-butyldimethylchlorosilane with the surface silanols. This system was chosen so that the surface free energy of the particles could be varied without introducing an extraneous wetting agent. The wicking method was used to obtain the liquid-particle-air contact angles. Water-air contact angles on glass beads increased with increasing silanizing reaction. The dispersive and the nondispersive contributions of the surface free energy were calculated from the contact-angle data. Nondispersive contribution decreased with increasing silanizing reaction while dispersive component remained unchanged. These silanized glass beads were dispersed in the continuous oil phase and the extent of particle retention at the water-oil interface and distribution to the water phase were determined. The experimental data indicate that the surface free energy of particles is the controlling parameter determining the transfer of particles from the oil phase to the water phase. Particle size in the range 5–20 μm had no significant effect, either on the particles retained or distributed to the water droplets.
Infant-directed behavior in young rhesus monkeys: Sex differences and effects of prenatal androgens.

Young (3-4 years old) laboratory-reared rhesus monkeys were observed in five 15-minute tests with 1-15-day-old infants. Males and females were equally likely to investigate infants. Females communicated more with infants by grin-lipsmacking and gurgling--gestures that were not shown by any males. More females presented the ventrum to infants than did males. Females contacted infants more than did males by grooming, crouching over, and having full body contact with them. To see whether prenatal androgens produced the male pattern of response, we conducted similar tests with pseudohermaphrodites (prenatally androgenized genetic females) and neonatally castrated males. On most sexually dimorphic behaviors, pseudohermaphrodites behaved more like females than like males. Castrated males, like females and pseudohermaphrodites, crouched over infants more than did intact males. Castrated males differed from females only on one infant-directed response, the grin-lipsmack. These comparisons showed that defeminization of the repertoire of infant-directed responses was measurable only in intact males. We conclude accordingly that prenatal androgens alone are not responsible for defeminization of this repertoire and that a contribution from postnatal androgens is likely to be necessary.
Central Role of the Early Colonizer Veillonella sp. in Establishing Multispecies Biofilm Communities with Initial, Middle, and Late Colonizers of Enamel

Human dental biofilm communities comprise several species, which can interact cooperatively or competitively. Bacterial interactions influence biofilm formation, metabolic changes, and physiological function of the community. Lactic acid, a common metabolite of oral bacteria, was measured in the flow cell effluent of one-, two- and three-species communities growing on saliva as the sole nutritional source. We investigated single-species and multispecies colonization by using known initial, early, middle, and late colonizers of enamel. Fluorescent-antibody staining and image analysis were used to quantify the biomass in saliva-fed flow cells. Of six species tested, only the initial colonizer Actinomyces oris exhibited significant growth. The initial colonizer Streptococcus oralis produced lactic acid but showed no significant growth. The early colonizer Veillonella sp. utilized lactic acid in two- and three-species biofilm communities. The biovolumes of all two-species biofilms increased when Veillonella sp. was present as one of the partners, indicating that this early colonizer promotes mutualistic community development. All three-species combinations exhibited enhanced growth except one, i.e., A. oris, Veillonella sp., and the middle colonizer Porphyromonas gingivalis, indicating specificity among three-species communities. Further specificity was seen when Fusobacterium nucleatum (a middle colonizer), Aggregatibacter actinomycetemcomitans (a late colonizer), and P. gingivalis did not grow with S. oralis in two-species biofilms, but inclusion of Veillonella sp. resulted in growth of all three-species combinations. We propose that commensal veillonellae use lactic acid for growth in saliva and that they communicate metabolically with initial, early, middle, and late colonizers to establish multispecies communities on enamel.
Modelling the differential impact of 1984 and 1950 sea-surface temperatures on sahel rainfall

Experiments with the GISS general circulation model are analysed to evaluate the differential impact of the contrastingly different 1984 and 1950 sea-surface temperature (SST) patterns on simulated precipitation over sub-Saharan Africa. Simulations yielded significantly lower August rainfall with 1984 SST as compared with 1950 SST. Differences in the moisture convergence into the Sahel responsible for the different resultant precipitation conditions are related to different evolutions of key circulation features. These are, in turn, consistent with some 1984 vs. 1950 SST differences in the Atlantic Ocean. In the model scenario, anomalously warm surface waters in July 1984 deepened the near-equatorial trough over the coastal waters adjacent to north-west Africa, promoting a circulation that eventually inhibited moisture advection from the Gulf of Guinea to the Sahel. This atmospheric evolution included a southward expansion of the West African Mid-tropospheric jet, which has been observed to occur during dry summers. The study suggests that this structure is a symptom of drought rather than a cause.
Chronic Liver Disease in Abusers of Alcohol and Parenteral Drugs: A Report of 204 Consecutive Biopsy‐Proven Cases

We studied a consecutive series of 204 patients who were admitted to a hospital for addictive diseases during 40 months and who had a liver biopsy. Parenteral drug abusers (n = 34) were significantly younger than alcohol abusers (n = 23) or abusers of both (n = 147) and had lower levels of serum alkaline phosphatase, total bilirubin, and aspartate aminotransferase than the other two groups. Chronic active hepatitis and chronic persistent hepatitis were more frequent (p less than 0.001) in abusers of parenteral drugs alone, whereas cirrhosis was found most often (p less than 0.001) in abusers of both alcohol and parenteral drugs. Cirrhosis was present in 10 of 39 (26%) simultaneous abusers of alcohol and parenteral drugs compared with 58 of 96 (60%) alcohol-abusing former parenteral drug abusers (p less than 0.001). Methadone maintenance treatment was not associated with cirrhosis. Thus, methadone-maintained patients who abuse alcohol and develop cirrhosis should remain in methadone maintenance treatment and receive concomitant alcoholism treatment. Also, these data further support the hypothesis that abusers of both alcohol and parenteral drugs have an increased risk of developing cirrhosis.
Statistical mechanics: The physics of where to go

Humans tend to explore unknown locations, but preferentially return to familiar places. The interplay between these two basic behaviours accounts for many of the scaling relations observed in human-mobility patterns.
Generation-recombination noise limited detectivities of impurity and intrinsic photoconductive 8 14μ infrared detectors

Abstract An analysis has been made of the dependences of the detectivities (D ∗ ) of impurity and intrinsic photoconductive 8–14μ infrared detectors on temperature for the situation in which only the bulk generation-recombination (gr) noise is important ; this case determines the upper limit to the detectivity of a background noise limited detector attainable by narrowing the field of view from the usual 180° angle to approach 0°. Hg-doped Ge and Hg0.8Cdo.2Te are considered as examples of impurity and intrinsic photoconductors, respectively, and it is found that for realistic optimum values of material parameters one can achieve a given D∗ at a higher operating temperature with the intrinsic photoconductor than with the impurity photoconductor, up to a certain D ∗ level.
Effects of Vertical Viscosity on Kelvin Waves

Abstract An analytic theory is presented for free, barotropic Kelvin waves subject to constant, vertical eddy viscosity on a semi-infinite, f-plane shelf of constant depth bordering a straight, vertical coast. A coastal boundary condition closes the solutions of Sverdrup (1927) and Fjeldstad (1929) by requiring that the component of vertically integrated, volume transport normal to the coast be zero just seaward of coastal boundary layers. This condition on offshore transport is then found to hold everywhere seaward of the coastal layers. One condition on the complex wavenumber components is the dispersion relation in which frictional bottom stress appears in an equivalent depth. The coastal boundary condition then fixes the wavenumber components. The effects of vertical viscosity are found to depend on the frequency ω′ relative to the inertial frequency and on the Ekman number E or, more conveniently, the vertical scale E½ of steady, bottom Ekman layers. Below a frequency dependent on E½, low-frequency K...