cssi/SciSciGPT-SciSciNet huggingface dataset:
Latent Semantic Analysis of the Languages of Life

We use Latent Semantic Analysis as a basis to study the languages of life. Using this approach we derive techniques to discover latent relationships between organisms such as significant motifs and evolutionary features. Doubly Singular Value Decomposition is defined and the significance of this adaptation is demonstrated by finding a phylogeny of twenty prokaryotes. Minimal Killer Words are used to define families of organisms from negative information. The application of these words makes it possible to automatically retrieve the coding frame of a sequence from any organism.
Are Economic Development and Education Improvement Associated with Participation in Transnational Terrorism

Using transnational terrorism data from 1980 to 2000, this study empirically examines the relationships between frequency of participation in transnational terrorism acts and economic development and education improvement. We find an inverse U-shaped association between the frequency of various nationals acting as perpetrators in transnational terrorism acts and per capita income in their respective home countries. As per capita incomes increase from relatively low levels, frequencies of participation in transnational terrorism increase. However, at sufficiently higher levels of per capita income, further increase in per capita income is negatively associated with the rate of participation in transnational terrorism. Education improvement from elementary to secondary is positively correlated with frequency of participation in transnational terrorism events, whereas further improvement from secondary to tertiary level is negatively correlated with participation in transnational terrorism. We also find that citizens of countries with greater openness to international trade, lower degree of income inequality, greater economic freedom, larger proportion of population with tertiary education, and less religious prevalence participate in transnational terrorism events less frequently.
Coherent Structures in Turbulent Boundary Layers

Research on coherent structure in boundary layers has identified characteristic signatures of several dynamic processes associated with two scales, an overall scale and a sublayer scale. The most useful variables are vorticity and shearing stress. After a brief review of this research, a preliminary report is given on work at GALCIT on a flow having a controlled pattern for the large eddies.
Transforming Palliative Care in Nursing Homes: The Social Work Role, edited by Mercedes Bern-Klug: New York: Columbia University Press, 2010, 350 pages, softcover, $45.00.

Death and dying are critical points in a life. End-of-life care is complex and often requires the effective collaboration of many disciplines. For those who work with individuals at the end of life...
Why Do People Vote in Semicompetitive Elections in China? A Reassessment of Voters' Subjective Motivations in Local People's Congress Elections

In the late 1970s and early 1980s, one of the post-Mao electoral reforms was semicompetitive elections, including those for local people's congresses. A better understanding of voters' subjective motivations in these elections is critical for explaining and predicting the significant effects of the elections on sociopolitical development in rapidly changing Chinese society. Using survey data collected in Beijing, China in 1995, we reexamine arguments and findings about voters' subjective motivations reported by Shi (1999a). Contrary to Shi's arguments and findings, we find that people with stronger democratic orientation and keener sense of internal efficacy are less likely to vote in these semicompetitive elections, while those who are identified with the regime and have affective attachments to the political authority are more likely to vote in the elections. In this paper, we present the differences between our arguments and findings and Shi's. Then, we draw some important political and theoretical implications from these differences.
Design and Application of Synthetic Peptides

A peptide consists of two or more amino acids linked together by amide bonds. Synthetic peptides are peptides that have been produced with organic, synthetic techniques to either mimic naturally occurring peptides or segments of naturally occurring proteins, or to interact in a specific manner with biological systems. Synthetic peptides are important molecules for biomedical research and medicinal chemistry that are useful for understanding biological systems and that have important applications in the development of vaccines and therapeutic agents and the process of de novo drug discovery. Keywords: Peptide Bond; Peptide; Residue; Epitope
Legal Encyclopedias: Research ‘Well Begun’

Finding a good place to start makes a big difference in how quickly and productively you research. Written for Student Lawyer magazine, this column examines an important starting point in legal research – the legal encyclopedia. With broad topic coverage, legal encyclopedias can often provide the background information needed to start students and lawyers down the path of a successful research project.
Effect of nurse-to-patient ratio in the intensive care unit on pulmonary complications and resource use after hepatectomy

BACKGROUND Nurse-to-patient ratios in the intensive care unit are associated with postoperative mortality, morbidity, and costs after some high-risk surgery. OBJECTIVE To determine if having 1 nurse caring for 1 or 2 patients ("more nurses") versus 1 nurse caring for 3 or more patients ("fewer nurses") in the intensive care unit at night is associated with differences in clinical and economic outcomes after hepatectomy. METHODS Statewide observational cohort study of 569 adults who had hepatic resection, 1994 to 1998. Hospital discharge data were linked to a prospective survey of organizational characteristics in the intensive care unit. Multivariate analysis was used to determine the association of nighttime nurse-to-patient ratios with in-hospital mortality, length of stay, hospital costs, and specific postoperative complications. RESULTS A total of 240 patients at 25 hospitals had fewer nurses; 316 patients in 8 hospitals had more nurses. No significant association between nighttime nurse-to-patient ratios and in-hospital mortality was detected. The overall complication rate was 28%. By univariate analysis, patients with fewer nurses had increased risks for pulmonary failure (5.8% vs 1.6%, relative risk, 3.6; 95% CI, 1.3-10.1; P=.006) and reintubation (10.8% vs 1.9%, relative risk, 5.7; 95% CI, 2.4-13.7; P<.001). By multivariate analysis, patients with fewer nurses had increased risk for reintubation (odds ratio, 2.9; 95% CI, 1.0-8.1; P=.04) and a 14% increase (95% CI, 3%-23%; P=.007) or an additional $1248 (95% CI, $384-$2112; P = .005) in total hospital costs. CONCLUSIONS Fewer nurses at night is associated with increased risk for specific postoperative pulmonary complications and with increased resource use in patients undergoing hepatectomy.
Kinetics of acid‐catalyzed degradation of cyclosporin A and its analogs in aqueous solution

The kinetics and mechanism of the degradation of cyclosporin A have been studied under aqueous acidic conditions. The rate of degradation was found to be specific acid-catalyzed over the pH range studied (1-4), with isocyclosporin A as the predominant degradation product. Selective reduction of the olefinic bond of the amino acid 2-N-methyl-(R)-((E)-2-butenyl)-4-methyl-L-threonine (MeBmt) did not affect the overall degradation kinetics and product distribution of cyclosporin A. These observations indicate that the alternative degradation pathway involving intramolecular alkoxy addition to the olefinic bond of amino acid MeBmt apparently does not significantly contribute to the overall degradation kinetics of cyclosporin A in the pH range 1-4. The chemical reactivity of O-acetyl-cyclosporin A was examined to probe the governing mechanism for the isomerization of cyclosporin A. Under identical conditions, O-acetyl-cyclosporin A showed a much greater chemical stability than cyclosporin A, consistent with a mechanism involving the hydroxyoxazolidine intermediate. The chemical stability of cyclosporin C, which contains two beta-hydroxyl groups, was also examined. The rate and product distribution for the degradation of cyclosporin C suggest that under aqueous acidic conditions it undergoes N,O-acyl migration solely at the amino acid residue MeBmt. Additionally, the impact of side-chain bulkiness of amino acid MeBmt was examined by studying the degradation kinetics of a series of cyclosporin A analogs.(ABSTRACT TRUNCATED AT 250 WORDS)
Transcriptional networks that mediate signals from reproductive tissues to influence lifespan

Aging and reproduction are two defining features of our life. Historically, research has focused on the well-documented decline in reproductive capacity that accompanies old age, especially with increasing maternal age in humans. However, recent experiments in model organisms such as worms, flies, and mice have shown that a dialogue in the opposite direction may be widely prevalent, and that signals from reproductive tissues have a significant effect on the rate of aging of organisms. This pathway has been described in considerable detail in the nematode Caenorhabditis elegans. Molecular genetic studies suggest that signals from the germline control a network of transcriptional regulators that function in the intestine to influence longevity. This network includes conserved, longevity-promoting Forkhead Box (FOX) family transcription factors such as DAF-16/FOXO and PHA-4/FOXA, nuclear hormone receptors, as well as a transcription elongation factor, TCER-1/TCERG1. Genomic and targeted molecular analyses have revealed that these transcription factors modulate autophagy, lipid metabolism, and possibly other cellular processes to increase the length of the animal's life. This review aims to provide an overview of the current knowledge on the genetic mechanism that underlies the reproductive control of aging with particular focus on the transcriptional regulators that constitute the main molecular players in this longevity pathway.
Post-transcriptional Regulation of Thyroid Hormone Receptor Expression by cis-Acting Sequences and a Naturally Occurring Antisense RNA

Thyroid hormone (T(3)) coordinates growth, differentiation, and metabolism by binding to nuclear thyroid hormone receptors (TRs). The TRalpha gene encodes T(3)-activated TRalpha1 (NR1A1a) as well as an antagonistic, non-T(3)-binding alternatively spliced product, TRalpha2 (NR1A1b). Thus, the TRalpha1/TRalpha2 ratio is a critical determinant of T(3) action. However, the mechanisms underlying this post-transcriptional regulation are unknown. We have identified a non-consensus, TRalpha2-specific 5' splice site and conserved intronic sequences as key determinants of TRalpha mRNA processing. In addition to these cis-acting elements, a novel regulatory feature is the orphan receptor RevErbAalpha (NR1D1) gene, which is transcribed from the opposite direction at the same locus and overlaps the TRalpha2 coding region. RevErbAalpha gene expression correlates with a high TRalpha1/TRalpha2 ratio in a number of tissues. Here we demonstrate that coexpression of RevErbAalpha and TRalpha regulates the TRalpha1/TRalpha2 ratio in intact cells. Thus, both cis- and trans-regulatory mechanisms contribute to cell-specific post-transcriptional regulation of TR gene expression and T(3) action.
Sources of Variation of Dry Matter Digestibility Measured by the Acid Insoluble Ash Marker

Abstract Four experiments were conducted to describe and quantify variation of measurement of digestibility of dry matter by the acid insoluble ash method. Cattle fed diets of corn silage or corn grain and sheep fed silage or high fiber pellets did not exhibit a pattern of variation of digestibility associated with grab fecal samples. Except for cattle fed corn grain, differences were not significant between mean digestibilities determined by total fecal collection versus acid insoluble ash. Considerably more variation was associated with digestibility measured by acid insoluble ash when cattle were fed high grain diets, primarily because such diets contain little acid insoluble ash. Components of variance were estimated to quantify sources of variation and compute sampling sizes. Three grab fecal samples from each of 10 steers fed a high moisture corn diet or three grab samples from one steer fed a corn silage diet would be required for a 95% confidence range of 5 percentage units. Components of variance for sources of laboratory assay variation showed that two samples in each of two assay sets would be required to obtain a 95% confidence range of .1 percentage unit in mean acid insoluble ash content.
Perceptions of the Need for Social Work in Assisted Living Facilities

Abstract A growing number of assisted living facilities (ALFs) are caring for elders with disabilities. Residents often need a broad array of supports as their physical, mental, and social functioning declines. The need for social work competencies was examined in this study of 140 ALF administrators. The 31 competencies were borrowed from the CSWE/SAGE-SW National Competencies Survey Report. Only 17 of the respondents employed professional social workers but facilities with social workers were significantly more likely to offer bereavement, crisis, family, and substance abuse counseling. The majority of administrators agreed that social work competencies could be useful in their facilities; however, non-social workers appeared to be performing many of these tasks.
A cable-swivel device for delivering shock to tail or harness electrodes

An inexpensive cable-swivel device for delivering shock to tail or harness electrodes is described.
Homeowners associations: Friend or foe to native desert avifauna? Conservation concerns and opportunities for research

Abstract The rapid urbanization experienced in arid environments worldwide has raised the issue of how wildlife adapt to such drastic landscape changes. Along the periphery of many desert cities are housing developments governed by homeowners associations. These homeowners associations often place strict restrictions on planted vegetation which may have implications for bird usage, particularly for those dependent on thorny vegetation. However despite the potential negative effects of such restrictions, such organizations may offer promise as a means of maintaining consistent landscape cover over a large urban area. Consideration of such organizations, through research and education can provide a means of pursuing conservation practice in difficult urban areas.
The secondary immune response to a hapten in vitro. Antigen concentration and the carrier effect.

The in vitro secondary stimulation of the production of anti-hapten antibody has been analyzed with a view to elucidating the role of the carrier molecule and cell-to-cell interactions in this response. Stimulation was carried out on fragment cultures of the spleens of irradiated BALB/c mice which had been reconstituted with 3–4 x 107 spleen cells from isologous mice previously immunized with DNP-Hy. The results indicated that the response was maximized by stimulation with DNP-Hy, the homologous complex, however anti-DNP antibody production could be obtained by stimulation with DNP on several nonhomologous carriers including poly-D-lysine, a poor immunogen. The results also indicated that while DNP-Hy and DNP-nonhomologous-carrier complexes were stimulatory at equally low DNP concentrations, at DNP concentrations over 10–6 M DNP-Hy was stimulatory, while DNP on nonhomologous carriers was inhibitory. The results are interpreted as indicating that: ( a ) the affinity of the antigen-cell interaction is more likely determined by multivalent binding than by carrier recognition, ( b ) that a stimulatory interaction of a polyvalent antigen with a B-lymphocyte cannot be excluded, ( c ) that if cell-to-cell interaction is necessary for stimulation, then both cells may recognize the same determinant, and ( d ) that the marked enhancement of antigenic stimulation attributable to carrier recognition may result from stimulatory interactions of cells recognizing different antigenic determinants. A mechanism is postulated whereby stimulation is dependent on the formation of stable complexes resulting from two cells sharing in the binding of numerous antigen molecules. Cells recognizing carrier determinants would increase the probability of such interactions particularly at high antigen concentrations.
Amplitude Versus Frequency-applications to Seismic Stratigraphy And Reservoir Characterization, Part I: Model

Amplitude versus Frequency (AVF) is an extension and supplement to Amplitude versus Thickness (AVTh), which makes dynamic use of decomposed frequency spectra to release additional information masked by the dominant frequency component of the seismic data. Models show that although a broadband spectrum remains critical for a better temporal resolution, dominant frequency of a seismic data set can be adjusted within bandpass to fit interpretational needs. Two interesting applications of AVF include identifying lithostratigraphic units and chronostratigraphic units for seismic stratigraphic analysis and thin-bed detuning in attribute analysis and inversion.
Multiplication of the H37Rv Strain of M. Tuberculosis on Blood and and Its Derivatives.

SummaryIt has been found that human blood, washed red cells, plasma, and serum contain all of the factors necessary for growing the H37Rv strain of M. tuberculosis from small inocula. The active component in red blood cells has been tentatively identified as hemoglobin. The essential ingredients in plasma or serum are more complex and require further study. A mixture of human fractions I and V was shown to be capable of initiating growth from large inocula but the data were not comparable with those obtained using whole serum. Similar results were obtained with bovine proantithrombin, fibrinolysin, and prothrombin.
A genetic system for alternative stable characteristics in genomically identical homozygous clones

Paramecium tetraurelia, stock d113, although completely homozygous, produces two kinds of genomically identical clones: N (nondischarge) clones incapable of trichocyst exocytosis (discharge) from intact cells in response to picric acid; and D (discharge) clones that do respond. These alternatives are irreversibly determined (at 27°C) during a determination sensitive period the first day after fertilization (autogamy, conjugation, or cytogamy): D parents are always determined to produce D progeny; N parents produce mostly N progeny if kept in exhausted medium, but mostly D progeny if kept in bacterized nutrient medium, throughout the sensitive period. If connecting bridges between mates persist long after the time for pair separation, the N member of N×D conjugant and cytogamous pairs produces D progeny even if exposed to exhausted medium throughout the sensitive period, thus indicating the presence in D mates of a D-determining cytoplasmic factor, δ, which overrides effects of external conditions. N and D determinations are brought about on newly developing somatic nuclei (macronuclear anlagen). After macronuclear development has been completed, determination is irreversible in it and its descendant macronuclei. M (mixed) clones produce N, D, and partial D cells; within these clones, diverse subclones can be selected. Crosses of d113 (N)×standard wild stock 51 (D) yield no segregation in F2, indicating no genomic difference between d113 (N) and wild type (D), δ may be a genic product regulating its own production. This results in “cytoplasmic inheritance” of D vs N in crosses of D×N followed by exhausted medium during the sensitive period. As with the only other well-analyzed comparable example, mating types, neither a genetic nor an epigenetic interpretation has yet been excluded for this system of developmental differentiation.
3d Reconstruction and Nonlinear Finite Element Analysis of the Embryonic Left Ventricle

Changes in mechanical loading in the developing heart produce changes in morphology and mechanical material properties [1–3]. Understanding the relationship of these changes to mechanical stress and strain in the left ventricle requires a geometrically accurate model of the entire ventricle including the trabecular pattern and material property, boundary condition, and loading specification. A 3D reconstruction and finite element technique were developed to reconstruct the heart from serial confocal sections and calculate stress and strain distributions over the volume for the passive state. Control hearts and two treatments, pressure overload and pressure underload, were modeled. The results show that stresses in the trabeculae are much larger than those in the ventricular walls. Strains in the pressure-overloaded hearts were significantly smaller than in control or underloaded, indicating the stiffer material properties more than compensate for the increased internal pressure.Copyright © 2007 by ASME
Performance Enhancement of Concrete Through the Use of Waste Injection Molding Pellets: A Preliminary Study of Viability:

The recycling of advanced polymers and composites is a major problem facing the composites industry due not only to problems related to the actual process itself but also to liability issues associ...
p38 MAPK Activity is Not Increased Early During Sustained Coronary Artery Occlusion in Preconditioned Versus Control Rabbit Heart

Our aim was to test the hypothesis that cardioprotection achieved with ischemic preconditioning (PC) involves increased activity of p38 mitogen-activated protein kinase (MAPK) early during sustained coronary artery occlusion. Using the isolated buffer-perfused rabbit heart model of regional ischemia, we quantified p38 MAPK activity (pmol/min/mg protein: by biochemical assay) at 5 and 10 min into coronary occlusion in hearts that first received PC ischemia or no intervention (controls), and in non-ischemic shams. Control hearts exhibited significant increases in p38 MAPK activity, averaging 883+/-142 and 1135+/-179 at 5 and 10 min of occlusion, v 144+/-49 in shams (P<0.05 and P<0.01). p38 MAPK activity was not, however, augmented with PC; rather, at 5 min into occlusion, activity was attenuated, averaging 432+/-72 (P=N.S. v sham). This early, modest reduction in p38 MAPK activity may be physiologically relevant: in additional hearts subjected to 30 min of sustained coronary occlusion and 2 h of reperfusion, infarct size (by tetrazolium staining: expressed as a % of the risk region) was 54+/-5% in hearts treated with SB 203580 (confirmed in our study to inhibit p38 MAPK activity at 5 min into occlusion) v 70+/-5% in vehicle controls (P<0.05). Thus, cardioprotection achieved with ischemic preconditioning in rabbit heart does not involve augmentation of p38 MAPK activity early during sustained coronary occlusion.
Is carotid endarterectomy justified in patients with severe chronic renal insufficiency

< 0.001 and p < 0.001, respectively). Of three patients with severe CRI suffering postoperative stroke, two had severe, difficult to control perioperative hypertension. Two patients with severe CRI who survived 30 days after operation suffered strokes 3 and 4 months postoperatively with one stroke-related death and another death not directly related to the stroke. One patient with severe CRI who survived CEA without stroke was alive 6 months after surgery. The 0% incidence of stroke and death following 14 CEAs in 10 patients with mild CRI was not significantly different from that in patients with normal renal function. Postoperative stroke was not associated with age, gender, history of cardiac disease, chronic preoperative hypertension, diabetes, smoking, or use of intraoperative shunts or patch closure. All three cardiac events occurred in diabetic patients, although they constituted only 26% of operations (p= 0.003). Other clinical characteristics were not associated with the occurrence of cardiac events. Patients with severe CRI are at significantly greater risk than others for postoperative stroke and death following CEA, possibly related to difficulty controlling severe perioperative hypertension. Age, gender, smoking, preoperative hypertension, diabetes, and known cardiac disease are not associated with an increased risk of postoperative stroke in any patient group. CEA can be justified only for carefully selected patients with severe CRI who have symptomatic carotid disease, acceptable operative risk factors, and a good long-term life expectancy. CEA in patients with mild CRI is associated with low risk, and these patients may be treated with the same consideration as patients with normal renal function.
The virtual oscilloscope: an impedance match to beginning ECE students

The design of a virtual oscilloscope, a personal computer interfaced to an analog-to-digital (A/D) interface that imitates the functioning of an oscilloscope, is described. It is shown that this system comes close to the ideal instrument for the student to use in the lab because the instrument functions are transparent, e.g., it does note have so many of the knobs that often get in the way of the measurement process. The design is based on the user interface of the Macintosh computer. The A/D hardware interface is based on an inexpensive single-board computer. Software, custom programmed in the Forth language to implement the virtual oscilloscope concept, links the two computers. The remote system design details, host system program design, and system operation are discussed. >
VELOCITY CHARACTERISTICS OF EVAPORATED PLASMA USING HINODE/EUV IMAGING SPECTROMETER

This paper presents a detailed study of chromospheric evaporation using the EUV Imaging Spectrometer (EIS) onboard Hinode in conjunction with hard X-ray (HXR) observations from Reuven Ramaty High-Energy Solar Spectroscopic Imager (RHESSI). The advanced capabilities of EIS were used to measure Doppler shifts in 15 emission lines covering the temperature range T = 0.05-16 MK during the impulsive phase of a C-class flare on 2007 December 14. Blueshifts indicative of the evaporated material were observed in six emission lines from Fe XIV-XXIV (2-16 MK). Upflow velocity (v up) was found to scale with temperature as v up (km s–1) ≈ 8-18T(MK). Although the hottest emission lines, Fe XXIII and Fe XXIV, exhibited upflows of >200 km s–1, their line profiles were found to be dominated by a stationary component in contrast to the predictions of the standard flare model. Emission from O VI-Fe XIII lines (0.5-1.5 MK) was found to be redshifted by v down (km s–1) ≈ 60-17T (MK) and was interpreted as the downward-moving "plug" characteristic of explosive evaporation. These downflows occur at temperatures significantly higher than previously expected. Both upflows and downflows were spatially and temporally correlated with HXR emission observed by RHESSI that provided the properties of the electron beam deemed to be the driver of the evaporation. The energy flux of the electron beam was found to be 5 × 1010 erg cm–2 s–1, consistent with the value required to drive explosive chromospheric evaporation from hydrodynamic simulations.
A Study of Individualized Instruction at the College Level

1. Recognition of the individual.-The use of aptitude and placement examinations, administered by the University and the Department, furnish an extensive diagnosis of each individual's innate abilities and the effects of his previous educational experiences. 2. Every student working at his best rate of speed and natural level of ability.-While superior students may find it unpleasant or exceedingly difficult to work on the dead level which is inevitable in any well-planned classroom aiming at steady progress, there is another group of students at the other extreme in ability who find the pace too swift and too difficult. Thus, in the typical classroom set-up the needs of about fifty per cent of the students are being adequately met, while those of the remainder are being unintentionally ignored. Under the plan of individualized instruction students are given wide latitude in determining the procedure best suited to their individual needs, preference, or living conditions. However, in order that capable students shall complete their work within a reasonable length of time, certain limits are set, requiring a minimum amount of work to be achieved each week or each month. 3. The responsibility for achievement rests on the individual.-When the student begins the course he becomes responsible for the mastery of a stated amount of work as defined in terms of a semester-course. Because unmethodical preparation is proscribed, the class-period is not taken up with the checking of lesson-preparation from day to day, but is left free for teacher-student conferences concerning individual problems and achievement.
New Pre-pandemic Influenza Vaccines: An Egg- and Adjuvant-independent Human Adenoviral Vector Strategy Induces Long-lasting Protective Immune Responses in Mice

Highly pathogenic avian H5N1 influenza viruses that are currently circulating in southeast Asia may acquire the potential to cause the next influenza pandemic. A number of alternate approaches are being pursued to generate cross-protective, dose-sparing, safe, and effective vaccines, as traditional vaccine approaches, i.e., embryonated egg-grown, are not immunogenic. We developed a replication-incompetent adenoviral vector-based, adjuvant- and egg-independent pandemic influenza vaccine strategy as a potential alternative to conventional egg-derived vaccines. In this paper, we address suboptimal dose and longevity of vaccine-induced protective immunity and demonstrate that a vaccine dose as little as 1 x 10(6) plaque-forming unit (PFU) is sufficient to induce protective immune responses against a highly pathogenic H5N1 virus. Furthermore, the vaccine-induced humoral and cellular immune responses and protective immunity persisted at least for a year.
Predictive analysis of two tone stream segregation via extended Kalman filter

Hearing engages in a seemingly effortless way, complex processes that allow our brains to parse the acoustic environment around us into perceptual sound objects, in a phenomenon called streaming or stream segregation. In this paper, we explore the hypothesis that the auditory system relies on the regularity inherent to each stream to segregate it from other competing streams in the scene. Tracking these regularities is achieved via a recursive prediction that tracks the evolution of each stream, using a Kalman filtering approach. The proposed approach combines spectral analysis operating at the level of the auditory periphery with a temporal analysis using Kalman tracking. To incorporate nonlinear relationships in the signal patterns, we employ an extended Kalman filter. This scheme is tested on sinusoidal patterns, or the two tone paradigm. The combined spectral and temporal analysis developed here is able to predict perceptual results of stream segregation by human listeners in a two tone paradigm.
The head‐up tilt test for diagnosing chronic fatigue syndrome

Sir, The recent paper by Naschitz et al .1 on the use of the head‐up tilt test with haemodynamic instability score (HIS) in the diagnosis of chronic fatigue syndrome (CFS) provides additional insight about the role of dysautonomia in the …
On designing comprehensible interactive hypermedia manuals

User's mental representations and cognitive strategies can have a profound influence on how they interact with computer interfaces (Janosky, Smith & Hildreth, 1986). However, there is very little research that elucidates such mental representations and strategies in the context of interactive hypermedia. Furthermore, interface design for hypermedia information presentation systems is rarely driven by what is known of users' mental models and strategies. This paper makes three contributions toward addressing these problems. First, it describes a novel cognitive model of comprehension of multimodal presentations for the specific application of explaining how machines work, and proposes guidelines for hypermedia design derived from this model. Since the development of this model draws heavily upon research in both cognitive science and computational modeling, a second contribution is that it contains a detailed review of literature in these fields on comprehension from static multimodal presentations. Third, it illustrates how cognitive and computational modeling are being used to inform the design of hypermedia information presentation systems about machines. This includes a framework for empirical validation of the model and evaluation of hypermedia design so that both theory and design can be refined iteratively.
Characterization of photodynamic and sonodynamic cytotoxicity by fluorescent probes

A variety of porphyrins and related structures can sensitize cells to light; many of these agents can also promote ultrasound-induced cytotoxicity. Subcellular sites of localization sensitizers with a sufficient fluorescence yield can be assessed by fluorescence microscopy, but this becomes difficult when (Phi) F is low. We have explored several indirect procedures for assessing examining loci of photodamage and sonodamage. Damage to lysosomal structures was probed with acridine orange, mitochondria with Rhodamine 123 and the plasma membrane with several diphenylhexatriene (DPH) derivatives. Additional information on alterations in heterogeneity of binding of diphenylhexatriene derivatives to photodamaged cells was provided by a distributed fluorescent lifetime study. Using a sulfonated benzochlorin, which photosensitizes cell-surface loci, we evaluated four DPH derivatives for their sensitivity to membrane damage. Anionic or cationic DPH derivatives were the most sensitive in this regard. Enhanced cytotoxicity associated with ultrasound + porphyrins yielded no detectable effects on mitochondrial or lysosomal structures, and barely detectable changes in membrane interactions with DPH derivatives, suggesting an 'all or none' effect.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Did Highways Cause Suburbanization

Between 1950 and 1990, the aggregate population of central cities in the United States declined by 17 percent despite population growth of 72 percent in metropolitan areas as a whole. This paper assesses the extent to which the construction of new limited access highways has contributed to central city population decline. Using planned portions of the interstate highway system as a source of exogenous variation, empirical estimates indicate that one new highway passing through a central city reduces its population by about 18 percent. Estimates imply that aggregate central city population would have grown by about 8 percent had the interstate highway system not been built.
Adjuvant Intraoperative Photodynamic Therapy in Head and Neck Cancer

Importance There is an immediate need to develop local intraoperative adjuvant treatment strategies to improve outcomes in patients with cancer who undergo head and neck surgery. Objectives To determine the safety of photodynamic therapy with 2-(1-hexyloxyethyl)-2-devinyl pyropheophorbide-a (HPPH) in combination with surgery in patients with head and neck squamous cell carcinoma. Design, Setting, and Participants Nonrandomized, single-arm, single-site, phase 1 study at a comprehensive cancer center among 16 adult patients (median age, 65 years) with biopsy-proved primary or recurrent resectable head and neck squamous cell carcinoma. Interventions Intravenous injection of HPPH (4.0 mg/m 2 ), followed by activation with 665-nm laser light in the surgical bed immediately after tumor resection. Main Outcomes and Measures Adverse events and highest laser light dose. Results Fifteen patients received the full course of treatment, and 1 patient received HPPH without intraoperative laser light because of an unrelated myocardial infarction. Disease sites included larynx (7 patients), oral cavity (6 patients), skin (1 patient), ear canal (1 patient), and oropharynx (1 patient, who received HPPH only). The most frequent adverse events related to photodynamic therapy were mild to moderate edema (9 patients) and pain (3 patients). One patient developed a grade 3 fistula after salvage laryngectomy, and another patient developed a grade 3 wound infection and mandibular fracture. Phototoxicity reactions included 1 moderate photophobia and 2 mild to moderate skin burns (2 due to operating room spotlights and 1 due to the pulse oximeter). The highest laser light dose was 75 J/cm 2 . Conclusions and Relevance The adjuvant use of HPPH-photodynamic therapy and surgery for head and neck squamous cell carcinoma seems safe and deserves further study. Trial Registration clinicaltrials.gov Identifier:NCT00470496
Intracultural communication rules and outcomes within three domestic cultures

Abstract This paper describes a qualitative study of intracultural communication rules and outcomes among Mexican-American, blacks and whites. Utilizing a rules/systems theoretical orientation, responses to open-ended questionnaires were content analyzed, producing five rule categories (politeness, role prescriptions, expression, content, and relationship climate) and five outcome categories (self-validation, relational validation, cultural validation, being understood, and goal accomplishment). Cultural similarities and differences are discussed.
A well-differentiated B-cell line is permissive for somatic mutation of a transfected immunoglobulin heavy-chain gene.

Abstract pSV2neo plasmids containing an IgM heavy-chain gene with nonsense mutations in either the variable (V) or the constant (C) region were transfected into four differentiated mouse plasma cell lines: S107 and the NSO fusion partner (myeloma cell lines) and 2C3 and 36.65 (hybridoma cell lines). The frequencies of reversion of the nonsense mutations in multiple independent transfectants were determined with the spot ELISA and rates of reversion were calculated by fluctuation analysis. Mutations in both V and C regions were confirmed by sequence analyses. In the S107 cell line, spontaneous point mutations occurred in the V region at a rate of approximately 5 x 10(-5)/bp per cell generation, > 400-fold higher than the rate of V-region mutation in the NSO cell line and considerably higher than the rates in 2C3 and 36.65 hybridoma cell lines. These studies suggest that S107 is a relatively permissive cell line in which V-region mutations can occur constitutively, even though it represents a late stage of B-cell differentiation. Further, the results show that the construct used contains sufficient information in its flanking and coding sequences to allow a relatively high rate of V-region mutation, at least in the S107 cell line.
How good is the tuberculin skin test

Purified protein derivative is a relatively crude material containing several different antigens. The results of a skin test with purified protein derivative are dependent on the immunologic reactivity of the recipient of the test, and the final interpretation is dependent on the individual interpreting the test. Despite these limitations, the tuberculin skin test (TST) is one of the most accurate medical tests available. Using conservative assumptions, I have estimated the sensitivity of the TST at approximately 95% and the specificity at approximately 99% to 99.5%.2 If these assumptions are correct, the TST is more accurate than most tests commonly used in clinical medicine. Despite this high degree of accuracy, the TST is not good enough to give valid results in serial skin testing programs in most hospitals and other medical facilities where the prevalence of new infection is low (including facilities ordinarily considered to be at “moderately high risk”). The table translates the conversion rate in a serial skin testing program to the actual transmission rate of tuberculosis infection assuming a sensitivity of 0.95 and a specificity of 0.99 to 0.995. If the annual conversion rate in a skin testing program is less than 1%, most conversions will be false positives and the predictive value of an individual conversion will be poor. Conversion rates above 2% increase the predictive value of the test to greater than 50%, and results in skin testing programs with annual conversions of greater that 2% probably represent mostly true transmission of tuberculous infection. Conversion rates between 1% and 2% probably represent equal numbers of false-positive and true-positive tuberculin reactions. This issue of Infection Control and Hospital Epidemiology presents four reports concerning the TST.3-6 These reports are welcome, as the results of most serial skin testing programs in medical environments go unreported. Cook et al.4 report TST results among healthcare workers in New York City. The conversion rate in their study was approximately 1.3% annually—a rate that suggests equal numbers of true-positive and false-positive conversions. The presence of some true-positive conversions is supported by the increased conversion rate in high-risk settings and among foreign-born individuals, who would be expected to have a higher than average risk in their community away from the workplace. Some of the increased conversion rate among high-risk workers was probably the result of semiannual testing in this group compared with annual testing for low-risk workers, as more frequent testing will increase the cumulative false-positive rate if such a rate is constant for each test.2 Garber et al.3 report results of skin testing programs in 19 microbiology laboratories in New York City. The incidence of TST conversion in their study of 1% probably slightly favors false conversions over true conversions,
Towards the crystal structure of glycerol dehydrogenase from Thermotoga maritima.

The NAD+-dependent glycerol dehydrogenase (EC 1.1.1.6) from the extremely thermophilic bacterium Thermotoga maritima has been crystallized in the presence of glycerol by the hanging-drop vapour-diffusion method using 2-methyl-2,4-pentanediol (MPD) as the precipitating agent. Crystals of the enzyme complexed with NAD+ have also been obtained. The crystals belong to the tetragonal system with space group I422 and unit-cell parameters a = 105.3, c = 134.5 A. They diffract to a maximum resolution of 1.4 A using synchrotron radiation (λ = 0.838 A). Crystals of the enzyme–NAD+ complex diffract to 2.5 A resolution using in-house Cu Kα radiation.
Low-temperature heat capacity of electrotransport-purified scandium, yttrium, gadolinium, and lutetium.

The low-temperature heat capacity of electrotransport-purified scandium, yttrium, gadolinium, and lutetium have been measured from 1 to 20 K. The electronic specific-heat constant \ensuremath{\gamma} and the Debye temperature ${\mathrm{CTHETA}}_{D}$ are determined to be 10.334\ifmmode\pm\else\textpm\fi{}0.011 mJ/g-at. ${\mathrm{K}}^{2}$ and 354.3\ifmmode\pm\else\textpm\fi{}1.0 K, respectively, for scandium, 7.878\ifmmode\pm\else\textpm\fi{}0.004 mJ/g-at. ${\mathrm{K}}^{2}$ and 244.4\ifmmode\pm\else\textpm\fi{}0.5 K, respectively, for yttrium, 6.380\ifmmode\pm\else\textpm\fi{}0.026 mJ/g-at. ${\mathrm{K}}^{2}$ and 163.4\ifmmode\pm\else\textpm\fi{}0.1 K, respectively, for gadolinium, and 8.194\ifmmode\pm\else\textpm\fi{}0.016 mJ/g-at. ${\mathrm{K}}^{2}$ and 183.2\ifmmode\pm\else\textpm\fi{}0.3 K, respectively, for lutetium. We believe that the above electronic specific-heat constants and Debye temperatures represent the intrinsic values for these four rare-earth metals. The use of the low-temperature heat-capacity results for these metals to evaluate the various contributions to the heat capacities of the magnetic lanthanide metals is examined. The total many-body enhancement factor and its components (the electron-phonon, electron-paramagnon, and spin-wave) are calculated.
Ultra wideband double-step hybrid rectangular dielectric resonator antenna

In this paper, a novel ultra wideband compact size hybrid rectangular step dielectric resonator antenna (DRA) is proposed. The aim from the design process is to get an ultra wide impedance bandwidth with stable radiation pattern through the operating frequency. The entire simulation results have been obtained by using CST simulation software. Measured results illustrate that the proposed DRA has a 10 dB impedance bandwidth of 122.58% from 6 GHz to 25 GHz.
Doubly excited states of the helium negative ion

Wave functions of doubly excited states $^{2}S$, $^{4}P^{o}$, $^{4}P$, $^{2}P^{o}$, and $^{2}D$ of the $n=2$ shell of ${\mathrm{He}}^{\ensuremath{-}}$ are studied in hypersherical coordinates. The interaction between the outer electron pair and the ${\mathrm{He}}^{+}(1s)$ open-shell core is treated by imposing boundary conditions at the core's surface and by spin recoupling. Adiabatic potential curves and the corresponding eigenvectors are studied as functions of the hyperradius $R$. Complex effects of channel couplings are analyzed, particularly for the $^{2}P^{o}$ states. Resonant "free-free" radiative transitions $^{2}S\ensuremath{\rightarrow}^{2}P^{o}$ and $^{4}P^{o}\ensuremath{\rightarrow}^{4}P$ are calculated and analyzed into contributions from the dipole operator at different $R$.
Sjögren syndrome: a review for the maxillofacial surgeon.

Sjogren syndrome is a multisystemic condition that predominantly involves the salivary and lacrimal glands. Also known as sicca complex, the disease often is underdiagnosed and poorly understood. This article provides a comprehensive review on Sjogren syndrome, with an emphasis on diagnosis and treatment modalities.
Relative contributions of the nucleus raphe magnus and adjacent medullary reticular formation to the inhibition by stimulation in the periaqueductal gray of a spinal nociceptive reflex in the pentobarbital-anesthetized rat

The organization in the brainstem of descending pathways of spinal inhibition was examined in the lightly pentobarbital-anesthetized rat. Thresholds for focal electrical stimulation-produced inhibition of the spinal nociceptive tail flick (TF) reflex were determined at one stimulation site in the midbrain periaqueductal gray and three sites in the rostral medulla: nucleus raphe magnus, and the adjacent medullary reticular formation contralateral and ipsilateral to the stimulating electrode in the periaqueductal gray. Lidocaine (0.5 microliter, 4%) was subsequently microinjected in the same and other medullary loci in the same coronal plane to produce a time-limited, reversible functional neural block. The functional block produced by 0.5 microliter of lidocaine microinjected in the medulla was determined to have a radius of 0.5 mm and was maximally efficacious during the first 30 min after its intramedullary microinjection. The stimulation threshold in the periaqueductal gray for inhibition of the TF reflex was not increased significantly when either the nucleus raphe magnus was fully blocked by lidocaine microinjected in three dorsoventral positions 1.0 mm apart or when the medullary reticular formation ipsilateral and contralateral were simultaneously fully blocked. Not until the nucleus raphe magnus and medullary reticular formation ipsilateral were simultaneously blocked by lidocaine was the stimulation threshold in the periaqueductal gray for inhibition of the TF reflex significantly increased. An increase in the periaqueductal gray stimulation threshold twice as great resulted when the nucleus raphe magnus and both the ipsilateral and contralateral medullary reticular formations were all simultaneously blocked by lidocaine. These results indicate that: (1) the nucleus raphe magnus is not a necessary bulbar relay in a descending antinociceptive pathway activated by stimulation in the midbrain periaqueductal gray; and (2) descending inhibitory pathways activated in the periaqueductal gray course medially as well as laterally in the rat ventral medulla.