cssi/SciSciGPT-SciSciNet huggingface dataset:
Heavy metals uptake mechanisms in a fixed-bed column by calcium-treated anaerobic biomass

Abstract This study investigated the feasibility of using anaerobic granules as a novel type of biosorbent for lead, copper, cadmium, and nickel removal from aqueous solutions using continuous column operation. Calcium treated anaerobic biomass was shown to be highly effective. The average biosorption column capacity for lead, copper, cadmium, and nickel before breakthrough occurred was 1.55, 0.88, 0.89, and 0.51 meq/g, respectively. The removal of Pb2+, Cu2+, Cd2+, and Ni2+ ions from the bed was accompanied by the elution of Ca2+ ions. While the feed pH was 4.0 for the four metals studied, the exit solution pH increased slightly (pH 5.0 to 5.5) for most of the experiments before the breakthrough point. At the breakthrough point, the pH value decreased to the value of the feed solution. The adsorbed metal ions were desorbed from the biomass by feeding into the column a 0.5 M of CaCl2 solution. Ion exchange was identified to be the dominant mechanism for the biosorption of nickel by the anaerobic biomass. For copper and cadmium, 77% and 82% of the total amount adsorbed was attributed to ion exchange, respectively. Eighteen percent and 15% of the total amount adsorbed of copper and cadmium was attributed to a complexation process, respectively. For the case of Pb ions, it was found that ion exchange accounted for almost 50% of the total uptake mechanism. Thirty percent of the total uptake mechanism was attributed to a precipitation mechanism. The remaining 20% was due to complexation. The results of this study indicate that the anaerobic sludge could be used as an effective biosorbent for the removal of heavy metals in a continuous flow system.
The effects of concurrent picture presentations on retelling of orally presented stories by adults with aphasia

This study investigated whether measures of verbal productivity, verbal disruption, information content, grammatical complexity, and grammatical well formedness would vary as a function of experimental conditions in which the presence of pictured stimuli was manipulated during the oral presentation and retelling of stories. Fifteen adults with aphasia retold stories under three experimental conditions: (i) concurrent presentation of oral and pictured versions of stories followed by a picture-supported retell, (ii) concurrent presentation of oral and pictured versions of stories followed by a 'free' retell, and (iii) orally presented stories followed by a free retell. Group analyses revealed no significant differences across experimental conditions for any of the dependent measures. Analyses of individual subjects' data revealed clinically important differences for several measures of information content, with individual subjects responding differently to the experimental conditions.
Hot vibrating white dwarf models of pulsating X-ray sources

The hypothesis that pulsating X-ray sources could be vibrating white dwarfs is investigated. The masses are calculated for several white-dwarf models having various modes of vibration which have the observed eigenfrequencies of the Centaurus X-3 and the Hercules X-1 sources. If the hypothesis is correct, Cen X-3 is vibrating radially in the fundamental mode or not higher than the first two overtones, and its mass is in the range 0.7-1.2 solar masses. The Her X-1 source would be vibrating in a quadrupole P mode, and would have a mass in the range 1.1-1.25 solar masses.
Distance Education: New Technologies and New Directions

Distance education has been undergoing incremental change over the past decade or so since the advent of the commercial Internet and the World Wide Web. However, we are currently on the cusp of advances that will facilitate experiential learning at a distance, reduce the cost of distance education production, expand access to education, and closely integrate formal education into the fabric of everyday life. Following a review of distance education technology past and present, this paper presents the evolving technologies that will facilitate the most important advances in the field and reviews their early applications.
OASIS-V: A Data-Base Driven CAI System.

AbstractA CAI system was designed to accommodate various educational presentation techniques. The system consists of a single program with data bases containing the material to be displayed. Control lines were added to each data base to direct the system in its presentation and to act as a controlling interface between user and computer. Editing, loading, and other support programs were written to transfer the burden of material and maintenance tasks from the user to the computer.
The laws of excluded middle and contradiction in checklist paradigm based fuzzy interval logic

This paper continues a study in fuzzy interval logic based on the Checklist Paradigm(CP) semantics of Bandler and Kohout. The law of excluded middle and the law of contradiction are investigated in the fuzzy interval logic system of negation, [¬ Bot, ¬ Top], which was defined by the Nicod(NOR) and the Sheffer(NAND) connectives of m 1 interval system, respectively. Both laws don't hold in the fuzzy logic with a classic negation, ¬ a = 1 − a; however, they do hold both with ¬ Bot and with ¬ Top in the checklist paradigm based fuzzy interval logic.
Racial and ethnic diversity in academic library collections: Ownership and access of African American and U.S. Latino periodical literature

Diversity is a familiar topic in library and information science, but how diverse are ARL collections and periodical indexes? This study measures ownership of and access to African American and Latino periodical literature to illustrate both the successes and failures in promoting racial and ethnic diversity in research libraries.
Medical Education in an Era of Health-Care Reform

Medical educators are facing a challenge today that is quite analogous to that addressed by Abraham Flexner, namely how to transform a legacy system of education that is no longer preparing future physicians adequately to meet contemporary expectations and responsibilities. In facing up this challenge, however, today's educators not only must equip students to deal effectively with the rapidly changing paradigms in health care and medical practice, they also must adapt their curricula and pedagogical methods to the demanding new paradigms of medical education. Their success in addressing these dual imperatives will determine whether the educational transformations currently underway will have as momentous an effect on the public's health as did those stimulated by Flexner a century ago.
Scale-dependent hydraulic conductivity in anisotropic media from dimensional cross-over

A cross-over from 1D conduction to 3D conduction with increasing scale is shown to account for the kind of scale-dependent hydraulic conductivity sometimes observed in anisotropic systems. The cross-over is investigated in the context of the application of continuum percolation theory to a random fractal model. The dimensional cross-over is defined in terms of a comparison between the correlation length from percolation theory and the system dimensions.
Western US college students: Banking preferences and marketplace performance

Retail banks generate new checking accounts by routinely promoting products and services to college students. Prospecting for new student customers is an ongoing and challenging task. Therefore, it is useful to know why students would switch from a bank currently serving them to a competing bank. With this knowledge, bank marketers can focus on relevant features and benefits when interacting with potential student customers. Retaining students as customers poses another challenge, so it is also important to know how well banks in the marketplace perform on certain attributes. This information enables a bank marketer to place attention on salient characteristics and ones that can differentiate a bank from competitors. This study yielded insights into the college–student market by evaluating reasons for students switching banks and selecting new banks. Students’ perceptions of bank performance in relation to product quality, price and service quality dimensions were also obtained. Aggregating student's opinions of different banks indicated the marketplace performance on these dimensions, thus suggesting areas for differentiation to achieve a competitive advantage.
Simulated Mutagenesis of the Hypervariable Loops of a Llama VHH Domain for the Recovery of Canonical Conformations

In this work, wildtype and mutated hypervariable regions of an anti-hCG llama VHH antibody were simulated via a molecular dynamics replica exchange method (REM). Seven mutants were simulated with the goal of identifying structural determinants that return the noncanonical H1 loop of the wildtype antibody to the type 1 canonical structure predicted by database methods formulated for conventional antibodies. Two cases with three point mutations yielded a stable type 1 H1 structure. In addition, other mutants with fewer mutations showed evidence of such conformations. Overall, the mutagenesis results suggest a marked influence of interloop interactions on the attainment of canonical conformations for this antibody. On the methodological front, a novel REM scheme was developed to quickly screen diverse mutants based on their relative propensities for attaining favorable structures. This multimutant REM (MMREM) was used to successfully identify mutations that stabilize a canonical H1 loop grafted on the llama ...
VCAM-1 signals during lymphocyte migration: role of reactive oxygen species

Vascular cell adhesion molecule-1 (VCAM-1) regulates leukocyte migration from the blood into tissues. VCAM-1 expression is induced on endothelial cells during inflammatory bowel disease, atherosclerosis, allograft rejection, infection, and asthmatic responses. During these responses, VCAM-1 forms a scaffold for leukocyte migration. VCAM-1 also activates signals within endothelial cells resulting in the opening of an "endothelial cell gate" through which leukocytes migrate. Immediately following this migration, the endothelial cell-endothelial cell contact is re-established. VCAM-1 outside-in signals are mediated by NADPH oxidase production of reactive oxygen species and subsequently activation of matrix metalloproteinases. These signals are required for endothelial cell shape changes and leukocyte migration. In addition, VCAM-1-activated signals in endothelial cells are regulated by cytokines indicating that it is important to consider both endothelial cell adhesion molecule expression and function during inflammatory processes.
Adding and subtracting vectors: The problem with the arrow representation

k) in generic mathematical and physics contexts. First, we replicated a number of previous findings of student difficulties in the arrow format and discovered several additional difficulties, including the finding that different relative arrow orientations can prompt different solution paths and different kinds of mistakes, which suggests that students need to practice with a variety of relative orientations. Most importantly, we found that average performance in the ijk format was typically excellent and often much better than performance in the arrow format in either the generic or physics contexts. Further, while we find that the arrow format tends to prompt students to a more physically intuitive solution path, we also find that, when prompted, student solutions in the ijk format also display significant physical insights into the problem. We also find a hierarchy in correct answering between the two formats, with correct answering in the ijk format being more fundamental than for the arrow format. Overall, the results suggest that many student difficulties with these simple vector problems lie with the arrow representation itself. For instruction, these results imply that introducing the ijk notation (or some equivalent) with the arrow notation concurrently may be a very useful way to improve student performance as well as help students to learn physics concepts involving vector addition and subtraction.
Apple Sauce Improves Detection of Esophageal Motor Dysfunction During High-Resolution Manometry Evaluation of Dysphagia

Background Esophageal manometry utilizes water swallows to evaluate esophageal motor abnormalities in patients with dysphagia, chest pain, or reflux symptoms. Although manometry is the gold standard for evaluation of these symptoms, patients with dysphagia often have normal results in manometry studies.
Estimating cotinine associations and a saliva cotinine level to identify active cigarette smoking in alaska native pregnant women.

Studies indicate nicotine metabolism varies by race and can change during pregnancy. Given high rates of tobacco use and limited studies among Alaska Native (AN) women, we estimated associations of saliva cotinine levels with cigarette use and second-hand smoke (SHS) exposure and estimated a saliva cotinine cutoff to distinguish smoking from non-smoking pregnant AN women. Using questionnaire data and saliva cotinine, we utilized multi-variable linear regression (n = 370) to estimate cotinine associations with tobacco use, SHS exposure, demographic, and pregnancy-related factors. Additionally, we estimated an optimal saliva cotinine cutoff for indication of active cigarette use in AN pregnant women using receiver operating characteristic (ROC) curve analysis (n = 377). Saliva cotinine significantly decreased with maternal age and significantly increased with cigarettes smoked per day, SHS exposure, and number of previous full term pregnancies. Using self-reported cigarette use in the past 7 days as indication of active smoking, the area under the ROC curve was 0.975 (95 % CI: 0.960–0.990). The point closest to 100 % specificity and sensitivity occurred with a cotinine concentration of 1.07 ng/mL, which corresponded to sensitivity of 94 % and specificity of 94 %. We recommend using a saliva cotinine cutoff of 1 ng/mL to distinguish active smoking in pregnant AN women. This cutoff is lower than used in other studies with pregnant women, most likely due to high prevalence of light or intermittent smoking in the AN population. Continued study of cotinine levels in diverse populations is needed.
On the Question of Whether a Disease is Familial

Abstract In trying to determine whether a disease is familial, epidemiologists often locate a source of cases and compare the proportion of affected relatives of these cases with that of the relatives of controls by the usual fourfold table techniques. In the model considered here, following Haenszel [5], the probability of being affected is a random variable, ρ, which is constant for members of the same “family” but which may vary from family to family. The usual tests are examined under a sampling scheme designed to simulate actual epidemiological practice, and it is found that if ρ is the same for all families, the proportions of affected relatives in the two groups are distributed as binomial proportions from the same universe. If ρ is not constant, the proportions are no longer binomial, but the tests used are shown to be consistent nevertheless. A large sample confidence interval for Eρ is derived.
THE USE OF AMYL NITRITE IN THE HEMODYNAMIC ASSESSMENT OF AORTIC VALVULAR AND MUSCULAR SUBAORTIC STENOSIS.

Abstract The hemodynamic effects of amyl nitrite were studied in 4 patients with valvular aortic stenosis and in 4 patients with muscular subaortic stenosis. In all 8 subjects, amyl nitrite significantly increased the left ventriculo-aortic gradients. Two patients in each group had nondiagnostic gradients in control tracings but had diagnostic postinhalation gradients. These observations indicate that the inhalation of amyl nitrite is a safe, convenient, and reproducible means of accentuating the gradient in both fixed-orifice aortic stenosis and muscular subaortic stenosis. Mechanisms relating to the development of increased obstruction of the outflow tract are believed to differ in the two groups.
FROM THE GUEST EDITOR—RESEARCH ON THE STIGMA OF MENTAL ILLNESS AMONG ETHNIC MINORITY POPULATIONS IN THE UNITED STATES

Although limited research has been done on the stigma of mental illness and specific ethnic minority populations in America, there is profound evidence that suggests that these groups experience ne...
Vibrational spectra ot aqueous oxalate ion

New experimental data on the infrared and Raman spectra of aqueous oxalate ion are presented. The data are consistent with a staggered (D/sub 2d/) configuration for the ion. The fundamental vibrational frequencies (cm/sup -1/) assigned on this basis are: A/sub 1/- 1486, 900, 449; B/sub 2/-- 1579, 524; and E- - 1310, 761, 301. (auth)
Schistosoma mansoni: physical and chemical factors affecting the mechanical properties of the adult male musculature.

Abstract The response of the musculature of male Schistosoma mansoni to various physical and ionic environments was determined. Contractile activity and tension of the parasite's musculature decreased when they were incubated in buffered salt solutions having an osmolality greater than 300 mOsm, a pH less than 6.8, or a temperature greater than 39 C. Except for potassium, high concentrations of inorganic ions reduced the tension of the parasite's musculature; high concentrations of potassium increased tension. In general the contraction rate of the male schistosome decreased when the concentration of an inorganic ion was below or above that found in Hanks' balanced salts solution. These results indicate that the musculature of S. mansoni is similar to smooth muscle found in mammals.
Optimizing virtual machine scheduling in NUMA multicore systems

An increasing number of new multicore systems use the Non-Uniform Memory Access architecture due to its scalable memory performance. However, the complex interplay among data locality, contention on shared on-chip memory resources, and cross-node data sharing overhead, makes the delivery of an optimal and predictable program performance difficult. Virtualization further complicates the scheduling problem. Due to abstract and inaccurate mappings from virtual hardware to machine hardware, program and system-level optimizations are often not effective within virtual machines. We find that the penalty to access the “uncore” memory subsystem is an effective metric to predict program performance in NUMA multicore systems. Based on this metric, we add NUMA awareness to the virtual machine scheduling. We propose a Bias Random vCPU Migration (BRM) algorithm that dynamically migrates vCPUs to minimize the system-wide uncore penalty. We have implemented the scheme in the Xen virtual machine monitor. Experiment results on a two-way Intel NUMA multicore system with various workloads show that BRM is able to improve application performance by up to 31.7% compared with the default Xen credit scheduler. Moreover, BRM achieves predictable performance with, on average, no more than 2% runtime variations.
Modelling, simulation, and experimental verification of the kinematics and dynamics of a double wishbone suspension configuration:

AbstractThis paper describes the non-linear modelling of a double wishbone suspension developed to investigate the non-linear kinematics and dynamics in the closed, spatial kinematic chain configur...
Gerade Rydberg states and ns 3Σ+u(1u,0−u) photoionization spectra of the rare gas dimers (n=2–6)

Transient absorption spectra of rare gas dimer Rydberg transitions in the ultraviolet, visible, and near infrared (220≤λ≤900 nm) spectral regions have been observed in electron beam excited rare gases. The most prominent molecular bands for He2, Ne2, Ar2, Kr2, and Xe2 are assigned to the mp 3Πg←ns 3Σ+u (He:n =2, 3≤m≤10; Ne:n =3, 4≤m≤10; Ar:n =4, 5≤m≤15; Kr:n =5, 6≤m≤16; Xe:n=6, 8≤m≤11) Rydberg series of the dimer. Adiabatic ionization potentials, relative to the ns 3Σ+u state, are determined by extrapolation of the series to their limits (m→∞) to be 34 361.4±30 cm−1 (4.260±0.004 eV) for He2, 34 396.3±25 cm−1 (4.265±0.003 eV) for Ne2, 29 351.9±15 cm−1 (3.639±0.002 eV) for Ar2, 28 428.5±10 cm−1 (3.525±0.001 eV) for Kr2, and 26 664.5±250 cm−1 (3.306±0.031 eV) for Xe2. Absorption bands which are ascribed to m’p 3Σ+g←ns 3Σ+u Rydberg series of Ne2(m’=4,6,8), Ar2(5≤m’≤10), Kr2(6≤m’≤10), and Xe2(m’=8,9) are also reported, and the ns 3Σ+u ionization potentials found to be identical to the respective values quoted ...
Influence of a Leptin Deficiency on Testicular Morphology, Germ Cell Apoptosis, and Expression Levels of Apoptosis‐Related Genes in the Mouse

Leptin-deficient (ob/ob) male mice are morbidly obese and exhibit impaired reproductive function. The objective of this study was to assess the effect of a leptin deficiency on testicular morphology, germ cell development, apoptotic activity within germ cells, and expression levels of apoptosis-related genes in the testis. Sixteen week-old ob/ob male mice (n = 8) and controls (n = 8) were killed, and their reproductive organs were weighed. Testes were processed for either histomorphological analysis (hematoxylin and eosin [H&E] staining), germ cell apoptosis assessment (deoxy-UTP-digoxigenin nick end labeling [TUNEL] method), or apoptosis-related gene expression analysis (microarray). Cross sections of the testes of leptin-deficient animals showed reduced seminiferous tubule area, fewer pachytene spermatocytes, and fewer tubules exhibiting elongated spermatids/mature spermatozoa. Condensation of germ cell nuclei and Sertoli cell vacuolization were evident in the testes of some ob/ob animals. Overall there was an elevation of apoptotic activity in the germ cells of ob/ob mice, particularly within the pachytene spermatocytes. With microarray technology, we identified 9 proapoptosis-related genes that were expressed at a significantly higher level in the testes of ob/ob mice than in the testes of the controls. Among these were members of the tumor necrosis factor receptor super family 1A and 5 (TNFR1 and 5) and peptidoglycan recognition proteins (associated with the extrinsic apoptotic pathway), and granzymes A and B, growth arrest and DNA damage inducible 45 gamma, sphingosine phosphate lyase 1, and caspase 9 (associated with the intrinsic apoptotic pathway). The results of the current study show that a leptin deficiency in mice is associated with impaired spermatogenesis, increased germ cell apoptosis, and up-regulated expression of proapoptotic genes within the testes.
Victimization, Substance Use, and HIV Risk Behaviors Among Gay/Bisexual/Two-Spirit and Heterosexual American Indian Men in New York City

American Indians and Alaska Natives are a people under siege, living within a colonial nation-state in a “fourth world.”1 This “indigenist” perspective foregrounds their historical and political context, including their experience of a succession of traumatic assaults, and is essential to contexualizing their current health status.2,3 Although preliminary evidence suggests that American Indian men might respond differently than American Indian women to the history of indigenous oppression,4 there is little empirical research on the health status of American Indian men. Data from the only 2 comprehensive reviews of American Indian men’s health indicate that they suffer from disproportionate rates of poor health compared with men in the general population.5 Additionally, life expectancy for American Indian men is significantly shorter than for White men or American Indian women, with early death caused in part by disproportionate rates of homicide, suicide, and motor vehicle accidents.6 Indeed, 5 of the top 10 leading causes of death for American Indian men (i.e., unintentional injuries, chronic liver disease and cirrhosis, diabetes mellitus, suicide, and homicide) are related to voluntary risky behaviors such as alcohol abuse, and might be preventable with appropriate public health intervention.7 A subgroup of American Indian men at increased risk for adverse health outcomes is self-identified gay, bisexual, or “two-spirit” men. Indigenous activists have adopted the term “two-spirit” as a way for gay, bisexual, or transgendered American Indians to name themselves outside the colonizing terms previously imposed upon them (e.g., “berdache”), to reconnect with tribal traditions related to sexuality and gender identity, and to transcend the Eurocentric binary categorizations of heterosexual versus homosexual and male versus female.8 Gay and bisexual American Indian men confront stressors associated with negotiating their multiple oppressed statuses and often must contend with heterosexism in American Indian communities as well as racism in gay communities.9–11
Transpedicular screw fixation of the lumbar spine: review and technique

Abstract Transpedicular fixation of the lumbar spine is an integral element in the surgical management of fractures, spondylolysthesis, neoplasms, scoliosis, and various other spine conditions. Experience over the past 15 years has better defined the indications, limitations, and potential risks of this surgical technique. Although segmental fixation using pedicle screws has many advantages, meticulous attention to detail and advanced training is required to avoid serious complications. This article outlines the pertinent clinical anatomy, preoperative evaluation, and surgical technique for transpedicular fixation of the lumbar spine.
The Relationships Between Parent Communication Patterns and Sons' and Daughters' Intimate Partner Violence Involvement: Perspectives From Parents and Young Adult Children

This study examined the communication patterns of parents and how they related to intimate partner violence (IPV) perpetration and victimization among young adult children. One hundred and ninety-three undergraduate students and 287 parents participated in this study. Hypothesis One predicted that parental conformity orientation would predict sons' and daughters' reports of IPV perpetration and victimization, whereas Hypothesis Two predicted that parental conversation orientation would predict sons and daughters reports of their own use of and an intimate partner's use of negotiation tactics. Both hypotheses received partial support. The results suggest that parent communication patterns have the potential to be both a risk and protective factor for young adult children's involvement in IPV. The findings also draw attention to important differences in the relationships that mothers and fathers have with their children, and differences between parent and child perspectives on parent communication.
Changes in the particle size and the concentration of cigarette smoke through the column of a cigarette

Abstract Changes in the particle size and the concentration of the main stream cigarette smoke particles through the cigarette column were studied with varying puff volume and butt length. It was found that the changes are caused by coagulation and filtration and that the following simple equations are applicable; N=(N 0 +β/K)V 0 /V−β/K β/KN+1=(β/KN 0 +1)exp(βt) , where N is number concentration. V is particle volume, K is coagulation constant, β is filtration coefficient, t is residence time given by puff volume and butt length, and subscript 0 means at t = 0 . Experimental results are presented which verify the equations.
Future wireless tutorial

Future wireless systems must find ways to make use of the increase of availability of spectrum for wireless applications that can co-exist with higher-priority users. Such techniques include: (1) Ultra Wideband (UWB) which attempts to share the spectrum by transmitting at very low power so as not to interfere with narrow-band transmissions, (2) Cognitive Radios that use spectrum sampling techniques to transmit at a given time, place and frequency that is in between that of the other users, and (3) advances in CMOS technology that allow operation in higher frequency bands like 60 GHZ. In order to effectively make use of this new spectrum availability, designers must use a multidisciplinary approach making use of new algorithms and modulation techniques, reduced power circuits, new microwave techniques and other innovations.
Numerical Representation of Groups in Cooperative Settings: Social Orientation Effects on Ingroup Bias

Investigates whether the greater ingroup favoritism typically expressed by numerical minorities, compared with numerical majorities, could be minimized by encouraging an interpersonal social orientation during intergroup cooperation. Study 1 examined how the type of social orientation adopted during cooperation affected the intergroup attitudes of numerical majorities and minorities. The outcomes of Study 1 showed that, compared to both a no-focus control and an interpersonally focused condition, a task-focus orientation was associated with an increase in ingroup bias among numerical majorities but a decrease in ingroup bias among numerical minorities. The results of Study 2 replicated those of Study 1 and showed support for the hypothesis that the effect of social orientation on ingroup bias among numerical majority and minority groups is mediated by ingroup identification and cohesion. Implications of these findings for understanding numerical representation effects and cooperative intervention outcomes are discussed.
The battered woman scale and gender identities

This paper describes the development of the Battered Women Scale (BWS), an instrument based on the Personal Attributes Questionnaire (PAQ) designed by Spence, Helmreich and Stapp (1974) and widely used to measure gender role trait ascription. Following arguments in the literature that battered women have particular traits, and the argument here that these traits are caused by experiences in battering relationships, the BWS was shown to successfully differentiate between women in three shelter houses and a sample of similar women who claim no abuse in their past. Further, although African-American women were generally very different in their gender role trait ascriptions than White women, they had patterns of reaction to battering very similar to white women. It is suggested that the BWS can be very useful to measure the value to battered women of shelter house programming on self-concepts.
Host cell reactivation of plasmids containing oxidative DNA lesions is defective in Cockayne syndrome but normal in UV-sensitive syndrome fibroblasts

UV-sensitive syndrome (UV(S)S) is a human DNA repair-deficient disease with mild clinical manifestations. No neurological or developmental abnormalities or predisposition to cancer have been reported. In contrast, Cockayne syndrome (CS) patients exhibit severe developmental and neurological defects, in addition to photosensitivity. The cellular and biochemical responses of UV(S)S and CS cells to UV are indistinguishable, and result from defective transcription-coupled repair (TCR) of photoproducts in expressed genes. We propose that UV(S)S patients develop normally because they are proficient in repair of oxidative base damage. Consistent with our model, we show that Cockayne syndrome cells from complementation groups A and B (CS-A, CS-B) are more sensitive to treatment with hydrogen peroxide than wild type or UV(S)S cells. Using a host cell reactivation assay with plasmids containing UV-induced photoproducts, we find that expression of the plasmid-encoded lacZ gene is reduced in the TCR-deficient CS-B and UV(S)S cells. When the plasmids contain the oxidative base lesion thymine glycol, CS-B cells are defective in recovery of expression, whereas UV(S)S cells show levels of expression similar to those in wild type cells. 8-oxoguanine in the plasmids result in similarly defective host cell reactivation in CS-A and CS-B cells; abasic sites or single strand breaks in the plasmids cause similar decreases in expression in all the cell lines examined. Repair of thymine glycols in the lacZ gene was measured in plasmids extracted from transfected cells; removal of the lesions is efficient and without strand bias in all the cell lines tested.
Mössbauer spectrometry study of the hyperfine fields and electronic structure of Fe-Co alloys.

We obtained 57Fe hyperfine-field parameters from Mossbauer spectra of Fe-Co alloys at 77 and 295 K. We also obtained the numbers of 3d electrons at Fe atoms by electron-energy-loss spectrometry (EELS). Together with bulk-magnetization data, we deduce how the occupancies of the 3d↑ and 3d↓ states at Fe atoms change with Co concentration. Changes in the total numbers of 3d electrons at Fe atoms were found to be small, with the Mossbauer data indicating a maximum of about 0.2 electrons at 30 at. % Co, and the EELS data indicating a change of similar magnitude but of opposite sign. From both our isomer-shift and hyperfine-magnetic-field (HMF) data, we deduce a slight reduction in the occupancy of 4s states with Co concentration of dn4s/dc=-0.02 electrons, which is principally due to a loss of 4s↓ electrons. The model employed for the calculation of HMF distributions in terms of conduction- and core-electron polarizations worked well for disordered Fe-Co alloys, and was used to analyze the changes in HMF after the disorder→order transformation. It showed that these HMF changes upon ordering are primarily due to changes in conduction-electron polarization.
Electrochemical and Thermal Studies of LiNi0.8Co0.15Al0.015O2 under Fluorinated Electrolytes

Abstract Electrochemical and thermal studies were performed to investigate: a) a fluorinated electrolyte (FE) containing fluoroethylene carbonate (FEC) as the co-solvent, and b) a non-fluorinated electrolyte (NFE) containing ethylene carbonate (EC) as the co-solvent, for lithium ion cells. Electrochemical impedance spectroscopy (EIS) measurements were performed on both electrolytes to estimate ionic conductivity. Cyclic voltammetry was employed to probe the effect of co-solvent fluorination on electrolyte oxidative stability. Cycling, rate capability, and EIS tests were performed on lithium ion coin cells (of 2032 size) to investigate the effect of the FEC co-solvent on the electrochemical performance of (LiNi 0.8 Co 0.15 Al 0.015 O 2 ) at the cathode. Differential scanning calorimetry (DSC) studies were performed to quantify the exothermic heat associated with delithiation of the (LiNi 0.8 Co 0.15 Al 0.015 O 2 ) cathode in the presence of electrolytes containing FEC and EC as the co-solvent respectively. A remarkable improvement in the thermal stability of (Li 0.36 Ni 0.8 Co 0.15 Al 0.015 O 2 ) was observed when FEC was used as the co-solvent. Besides the upward shift of the onset temperature by 24 °C, the exothermic heat was also reduced by 15%. Cells prepared with FE showed good electrochemical performance at low rates and moderate performance at high rates when compared to cells prepared with NFE.
High-Income and Low-Income Adolescents' Views of Special Education.

As a component of a comprehensive qualitative study of social class influences on schooling, 34 high-income and 40 low-income adolescents were interviewed about various aspects of special education. Qf the low-income respondents, 55% had been classified as learning disabled, mildly mentally handicapped, or emotionally disturbed and had received special education services at some time during theirschooling; whereas only two (6%) high-income adolescents had been classified as learning disabled. Nonclassified low-income students also had considerable contact with friends, neighbors, and relatives who had received special education services. The majority of low-income adolescents had ambivalent or negative feelings about special education. High-income adolescents had little contact with students classified as handicapped and, with few exceptions, they saw special education as a helpful, necessary service. This study indicates that there were social class distinctions in adolescents' opinions and evaluations o...
Basic Chemical Principles, Second Edition (Peters, Edward I.; Kowerski, Robert C.)

The second edition of the Basic Chemical Principles textbook by Peters and Kowerski shows a refinement of a method that leads beginning students into the study of chemistry.
Rapid isolation of mouse DNA from cells in tissue culture

A rapid method for the isolation of DNA from mouse cells grown in tissue culture is described. Cells are lysed in 0.24 m sodium phosphate, pH 6.8 buffer, containing 1% sodium dodecyl sulfate, 8 m urea, and 10−3m ethylene-diaminetetraacetic acid, and the crude lysate applied to a column of hydroxyapatite. RNA and proteins are removed from the column with 0.24 m sodium phosphate buffer containing 8 m urea while DNA is selectively eluted with 0.48 m sodium phosphate buffer. There is almost total recovery of cellular DNA from the column and the DNA is virtually free from proteins and RNA. This extraction procedure indicates that a mouse cell contains about 8 × 10−6 μg of DNA.
Relevance reconsidered—towards an agenda for the 21st century: introduction to special topic issue on relevance research

The publication of this issue marks a special event for the Journal of the American Society for Information Science: the introduction of special topics issues. It seems appropriate that the first issue is devoted to the topic of relevance, acknowledged as the most fundamental and much debated concern for information science, it being the tacit or explicit judgment of end-users about the output of information retrieval systems. Early on, information scientists recognized that the concept of relevance was integral to information system design, development, and evaluation. However, there was little agreement as to the exact nature of relevance and even less that it could be operationalized in systems or for the evaluation of systems. While this lack of agreement continues to an extent at the present, some common understandings have developed, and these are reflected in the papers in this issue. © 1994 John Wiley & Sons, Inc.
The impact of race on survival in uterine serous carcinoma: A hospital-based study

Abstract Objective Although less common than endometrioid carcinoma, uterine serous carcinoma (USC) accounts for a disproportionate number of endometrial cancer-related deaths. It is relatively more common in black compared to white women. The aim of our study is to analyze the impact of race on survival in USC. Methods We conducted a retrospective review in women with USC managed at two large urban medical centers. Clinical and histopathologic parameters were retrieved. Recurrence and survival data were obtained from medical records and the Surveillance, Epidemiology, and End Results (SEER) registry. Differences in overall survival between African American and Caucasian women were compared using Kaplan–Meier curves and log rank test for univariate analysis. Cox regression models for multivariate analyses were built to evaluate the relative impact of the various prognostic factors. Results One hundred seventy-two women with USC were included in this study, including 65 Caucasian women and 107 African American women. Both groups were similar with respect to age, stage at diagnosis, angiolymphatic invasion ( p =0.79), and the depth of myometrial invasion ( p =0.36). There was no statistical difference in overall survival between African American and Caucasian patients in univariate analysis ( p =0.14). In multivariate analysis, stage at diagnosis, angiolymphatic invasion, and depth of myometrial invasion, but not race, were significantly associated with overall survival. Conclusion In this study, African American women with USC had a similar survival to Caucasian women. This suggests that the racial differences seen in USC at a larger population level may be diminished in hospital-based studies, where women are managed in a uniform way.
Effect of Vitamin D Receptor Genotypes on Calcium Absorption, Duodenal Vitamin D Receptor Concentration, and Serum 1,25 Dihydroxyvitamin D Levels in Normal Women

It is well established that bone mineral density is under strong genetic control. Recently it was reported that the Bsm I restriction fragment length polymorphism of the vitamin D receptor (VDR) gene could account for up to 75% of the genetic variance in bone mineral density. However, the physiological basis for such an effect has not been established. The VDR gene codes for the vitamin D receptor protein which regulates intestinal calcium absorption. In order to assess the biochemical basis we studied the effect of common allelic variation of the VDR gene on intestinal VDR protein concentration, calcium absorption, and serum 1,25 dihydroxyvitamin D (1,25(OH)2D). Ninety-two Caucasian women were genotyped for Bsm I and Taq I polymorphism at the VDR gene locus. From these we compared 49 young women aged 25-35 years and 43 elderly women aged 65-83 years, who had all three measurements performed. There were no significant differences in intestinal VDR protein concentration, serum 1, 25(OH)2D, or radioactive calcium absorption among VDR genotype groups. Therefore, the small intestine does not seem to be a target for VDR gene polymorphism.
Are teachers’ education, major, and credentials related to classroom quality and children's academic gains in pre-kindergarten?

Abstract To date, few studies of state-funded pre-kindergarten have fully addressed questions about the association between teachers’ education, major, and credentials with classroom quality or children's academic gains. The current paper uses data from the National Center for Early Development and Learning's (NCEDL) Multi-State Study of Pre-Kindergarten, involving 237 pre-kindergarten classrooms and over 800 children, randomly selected from six states with well-established state-funded pre-kindergarten programs. The study includes multiple days of classroom observation, direct child assessments of children's early academic skills in the fall and spring of the pre-kindergarten year, and questionnaires from teachers. For the current paper, teachers’ education has been operationalized in three different ways (years of education, highest degree, and Bachelor's versus no Bachelor's). Additionally, the paper considers the role of college major, state teaching certification, and CDA credential. Consistent with findings in the K-12 literature, this study finds few associations between any of the measures of education, major, or credentials and classroom quality or children's outcomes. Teachers’ education, regardless of how it is operationalized, is linked to gains in children's math skills across the pre-k year, and the CDA credential is linked to children's gains in basic skills; however, education, training, and credentialing are not consistently related to classroom quality or other academic gains for children.
Rapid patterning of slurry-like elastomer composites using a laser-cut tape

We present a cleanroom-free, simple and low-cost fabrication approach utilizing a laser-cut tape for rapidly patterning slurry-like elastomer composites. A conductive polydimethylsiloxane (PDMS) composite was chosen for demonstration in this paper due to its wide use of sensing and heating in many applications. Two fabrication schemes were developed: embedding in a PDMS matrix and relieving on a PDMS substrate. In both schemes, the patterns were first inscribed on adhesive tape using a CO2 laser. The patterned tape then served as a positive mask when spreading the conductive PDMS over it. The patterns were eventually transferred to a substrate after scraping the excessive composite with a razor blade and then removing the tape. The feature resolution of the technique was about 90‐100 μm primarily determined by the laser beam diameter, the translational speed and the power. The height of the patterned structures was associated with the thickness of the tape, which ranged from 76.1 ± 4.3 μm to 168.9 ± 8.2 μm in this study. A thicker structure can be achieved by stacking more adhesive tapes. For a practical demonstration, the conductive PDMS was patterned on a PDMS substrate serving as a heating element. The elastomeric microheater was successfully heated to 92 ◦ C with a power of 210 ± 12 mW applied. (Some figures in this article are in colour only in the electronic version)
The effect of ion energy on the formation of the silicon carbide interface of hydrogenated amorphous carbon films grown on silicon by plasma assisted chemical vapor deposition

Abstract The interface of hydrogenated amorphous carbon films grown on single crystal silicon by plasma assisted chemical vapor deposition from methane was studied by angle-resolved X-ray photoelectron spectroscopy. The effect of varying RF power for films grown on a RF-powered electrode was investigated, as well as the effect of varying pulse height for films grown under high voltage pulsed biasing on a non-RF-powered electrode. The spectra of the films deposited at the powered electrode revealed the presence of an approximately stoichiometric silicon carbide layer at the interface. In contrast, the interfacial carbide for films formed at the pulsed biased electrode was found to be nonstoichiometric and silicon rich, which could be ascribed to the relatively much smaller high-energy ion flux to the substrate. The effective thickness of the interfacial layer, as determined from the angle-resolved spectra, however, correlated well with the kinetic energy of plasma ions impinging on the silicon substrate, regardless of the average stoichiometry. The thickness varied from ~ 4 to 12 A for kinetic energies ranging from ~ 150 to 1100 eV. The results indicate that the thickness of the interfacial carbide is determined by the average penetration depth of plasma ions into the silicon substrate, as controlled by their kinetic energy.
Assessment of right ventricular function in patients with congestive heart failure by echocardiographic automated boundary detection

Abstract In conclusion, our findings demonstrate that right ventricular function in patients with chronic heart failure due to dilated cardiomyopathy can be reliably assessed by an echocardiographic ABD technique, which is superior to conventional manual echocardiographic methods. This technique, providing a real-time display of right ventricular function without exposure to radiation, offers important advantages when compared with radionuclide ventriculography. For these reasons, we believe that in patients with heart failure, the ABD technique will have an expanding role in noninvasively assessing right ventricular function.
RAREFIED AEROTHERMODYNAMIC PREDICTIONS FOR MARS GLOBAL SURVEYOR

Mars Global Surveyor (MGS) successfully completed its first phase of aerobraking in early 1998 and is the rst planetary mission to use aerobraking as a primary means of customizing its orbit to achieve its mission objectives. The aerobraking requirements together with post-launch anomalies presented a unique challenge to provide accurate predictions of the aerothermodynamic environment of the spacecraft in the rare transitional flow regime. Direct Simulation Monte Carlo (DSMC) and free molecular techniques were used to provide heating and aerodynamic predictions and to investigate a variety of rarefied flow phenomena across the regime; MGS is the first major planetary mission in which rare flow predictions have played such a critical role all the way through design, mission planning, and operational phases. This paper summarizes these studies with emphasis on transitional-flow and gas-surface interaction phenomena.