cssi/SciSciGPT-SciSciNet huggingface dataset:
Group communicators, perceived entitativity, and persuasion: A self-validation analysis

Abstract The extent to which a group is cohesive or entitative has been shown to play a key role in how much perceivers attend to and process group-relevant information. However, less is known about how entitativity may guide the metacognitive perceptions that people produce toward a group. The current research examined how group message sources that differ in entitativity can influence how confident people are in their thoughts about a communication. In Study 1, participants rated a highly entitative group as more likely to present valid information compared to a low entitativity source. Consistent with these beliefs, Study 2 participants were more confident and had attitudes that were more reflective of their message-related thoughts when source entitativity was high rather than low. Furthermore, the results of Study 3 suggest these self-validation effects may be contingent on high processing motivation and ability. Implications for the study and practice of persuasion are discussed.
TH-CD-BRB-00: Current Topics in SRS/SBRT

Stereotactic radiosurgery (SRS) and stereotactic body radiation therapy (SBRT) have now been applied clinically for several decades. The accumulation of published technical and clinical studies currently available has offered insights into both the efficacy and special concerns associated with the delivery of the stereotactic approach to different disease sites. The last few years have witnessed significant advances in both delivery technology and planning approaches. Digital linacs equipped with high dose rate flattening-filter free (FFF) beams are particularly well suited to stereotactic applications. Modern image guidance provides a framework for managing uncertainties and optimizing margins. Knowledge-based approaches can automate many aspects of the treatment planning process. This session will provide an overview of these important technical considerations in SRS/SBRT, and discuss approaches to safe clinical implementation. Learning Objectives: 1. Understand commissioning and application of FFF beams in SRS and SBRT applications 2. Understand how image guidance plays a role in the design of treatment margins and the management of uncertainties 3. Understand the methodology and application of knowledge-based planning to SRS and SBRT Kevin Moore: research funding, honoraria and travel support from Varian Medical Systems Kristy Brock: licensing agreement with RaySearch Laboratories for deformable registration technology Richard Popple: research funding and honoraria from Varian Medical Systems Timothy Solberg: honoraria from BrainLAB, ownership of Global Radiosurgery Services
Comparison of Two Reformulation-Linearization TechniqueBased Linear Programming Relaxations for Polynomial Programming Problems

In this paper, we compare two strategies for constructing linear programming relaxations for polynomial programming problems using a Reformulation-Linearization Technique (RLT). RLT involves an automatic reformulation of the problem via the addition of certain nonlinear implied constraints that are generated by using the products of the simple bounding restrictions (among other products), and a subsequent linearization based on variable redefinitions. We prove that applying RLT directly to the original polynomial program produces a bound that dominates in the sense of being at least as tight as the value obtained when RLT is applied to the joint collection of all equivalent quadratic problems that could be constructed by recursively defining additional variables as suggested by Shor.
Meta‐analysis of naltrexone and acamprosate for treating alcohol use disorders: when are these medications most helpful?

Aims Although debates over the efficacy of oral naltrexone and acamprosate in treating alcohol use disorders tend to focus on their global efficacy relative to placebo or their efficacy relative to each other, the underlying reality may be more nuanced. This meta-analysis examined when naltrexone and acamprosate are most helpful by testing: (1) the relative efficacy of each medication given its presumed mechanism of action (reducing heavy drinking versus fostering abstinence) and (2) whether different ways of implementing each medication (required abstinence before treatment, detoxification before treatment, goal of treatment, length of treatment, dosage) moderate its effects.
Oops I Did It or "It Wasn't Me:" An Examination of Psychological Contract Breach Repair Tactics

Research on psychological contracts has clearly established that psychological contract breach (PCB), which represents the extent to which the employee is aware of an unfulfilled obligation on the ...
The E5 protein of human papillomavirus type 16 perturbs MHC class II antigen maturation in human foreskin keratinocytes treated with interferon-γ

Abstract Major histocompatibility complex (MHC) class II antigens are expressed on human foreskin keratinocytes (HFKs) following exposure to interferon gamma. The expression of MHC class II proteins on the cell surface may allow keratinocytes to function as antigen-presenting cells and induce a subsequent immune response to virus infection. Invariant chain (Ii) is a chaperone protein which plays an important role in the maturation of MHC class II molecules. The sequential degradation of Ii within acidic endocytic compartments is a key process required for the successful loading of antigenic peptide onto MHC class II molecules. Since human papillomavirus (HPV) 16 E5 can inhibit the acidification of late endosomes in HFKs, the E5 protein may be able to affect proper peptide loading onto the MHC class II molecule. To test this hypothesis, HFKs were infected with either control virus or a recombinant virus expressing HPV16 E5 and the infected cells were subsequently treated with interferon-γ. ELISAs revealed a decrease of MHC class II expression on the surface of E5-expressing cells compared with control virus-infected cells after interferon treatment. Western blot analysis showed that, in cells treated with interferon gamma, E5 could prevent the breakdown of Ii and block the formation of peptide-loaded, SDS-stable mature MHC class II dimers, correlating with diminished surface MHC class II expression. These data suggest that HPV16 E5 may be able to decrease immune recognition of infected keratinocytes via disruption of MHC class II protein function.
Delivery of orally supplemented α-tocotrienol to vital organs of rats and tocopherol-transport protein deficient mice

The natural vitamin E tocotrienol (TCT) possesses biological properties not shared by tocopherols (TCP). Nanomolar α-TCT, not α-TCP, is potently neuroprotective (JBC 275:13049; 278:43508). Tocopherol-transport protein (TTP) represents the primary mechanism for maintaining normal α-TCP concentrations in plasma and extrahepatic tissues. TTP primarily transports α-TCP and has low affinity for α-TCT. There are no studies that have investigated tissue delivery of α-TCT when orally gavaged on a long-term basis. A long-term study was conducted to examine the effects of α-TCT or α-TCP supplementation, either alone or in combination, on tissue levels. Rats were maintained on a vitamin E-deficient diet and gavaged with α-TCT or α-TCP alone or in combination. Five generations of rats were studied over 60 weeks. TTP-deficient mice were supplemented with TCT and bred to examine tissue delivery of oral α-TCT. Orally supplemented α-TCT was effectively delivered to most tissues over time. When co-supplemented, α-TCP outcompeted α-TCT for transport systems delivering vitamin E to tissues. To evaluate the significance of TTP in α-TCT delivery to tissues, tissue levels of α-TCT in supplemented TTP-deficient mice were studied. α-TCT was transported to several vital organs in TTP-deficient mice. α-TCT restored fertility in TTP-deficient mice. In sum, orally supplemented α-TCT was successfully delivered to several vital organs. The transport efficiency of α-TCT to tissues may be maximized by eliminating the co-presence of α-TCP in the oral supplement. Examination of whether α-TCT may benefit humans suffering from neurological disorders because of congenital TTP deficiency is warranted.
Broadband plasma absorber

Summary form only given, as follows. A tenuous plasma generated in a background gas at atmospheric pressure is highly collisional. The cold collisional dispersion relation was used to model electromagnetic effects. For a plasma generated by a point source such as an ultraviolet flash lamp the electron number density decreases as a function of distance from the source. An Epstein profile was used to model the plasma gradient. Calculations based on an Epstein profile quantify the reflection coefficient and absorption for propagation through the plasma as a function of frequency. These effects were quantified for air and noble gases. Generation of plasma can be achieved by photoionization of the organic vapor TMAE and containment in a thin shell Mylar structure. This containment vessel has low backscatter and is suitable for electromagnetic measurements
Oral antimycobacterial therapy in chronic cutaneous sarcoidosis: a randomized, single-masked, placebo-controlled study.

Importance Sarcoidosis is a chronic granulomatous disease for which there are limited therapeutic options. This is the first randomized, placebo-controlled study to demonstrate that antimycobacterial therapy reduces lesion diameter and disease severity among patients with chronic cutaneous sarcoidosis. Objective To evaluate the safety and efficacy of once-daily antimycobacterial therapy on the resolution of chronic cutaneous sarcoidosis lesions. Design and Participants A randomized, placebo-controlled, single-masked trial on 30 patients with symptomatic chronic cutaneous sarcoidosis lesions deemed to require therapeutic intervention. Setting A tertiary referral dermatology center in Nashville, Tennessee. Interventions Participants were randomized to receive either the oral concomitant levofloxacin, ethambutol, azithromycin, and rifampin (CLEAR) regimen or a comparative placebo regimen for 8 weeks with a 180-day follow-up. Main Outcomes and Measures Participants were monitored for absolute change in lesion diameter and decrease in granuloma burden, if present, on completion of therapy. Observations In the intention-to-treat analysis, the CLEAR-treated group had a mean (SD) decrease in lesion diameter of –8.4 (14.0) mm compared with an increase of 0.07 (3.2) mm in the placebo-treated group (P = .05). The CLEAR group had a significant reduction in granuloma burden and experienced a mean (SD) decline of –2.9 (2.5) mm in lesion severity compared with a decline of –0.6 (2.1) mm in the placebo group (P = .02). Conclusions and Relevance Antimycobacterial therapy may result in significant reductions in chronic cutaneous sarcoidosis lesion diameter compared with placebo. These observed reductions, associated with a clinically significant improvement in symptoms, were present at the 180-day follow-up period. Transcriptome analysis of sarcoidosis CD4+ T cells revealed reversal of pathways associated with disease severity and enhanced T-cell function following T-cell receptor stimulation. Trial Registration clinicaltrials.gov Identifier:NCT01074554
Abstract 2980: Role ofXPAandp53genes in the induction of centrosomal amplification in mice exposed to Zidovudine (AZT)

Proceedings: AACR 101st Annual Meeting 2010‐‐ Apr 17‐21, 2010; Washington, DC In cultured cells, exposure to the highly-effective nucleoside reverse transcriptase inhibitor (NRTI) Zidovudine (AZT) induces genomic instability, causing cell cycle arrest, micronuclei, sister chromatid exchanges, and shortened telomeres. In previous studies, we demonstrated for the first time that AZT induced centrosomal amplification (defined as > 2 centrosomes /cell), a novel manifestation of genotoxicity. Here, bone marrow cells from wild type C57BL/6J mice and their transgenic counterparts with genotypes XPA −/− p53 +/+, XPA−/−p53 +/− and XPA−/−p53 −/−, were cultured in vitro to obtain homogeneous populations of mesenchymal-derived fibroblasts. Wild type, and DNA repair- / p53-deficient cells (n=3/group) were exposed to 0, 10 or 100 μM AZT for 24 hr, and centrosomal amplification was examined by immunohistochemical (IHC) staining with an anti-pericentrin antibody. Values for centrosomal amplification (% of cells with ≥2 centrosomes/cell) were 12.2, 15.2 and 19.7% in wild type (XPA +/+ p53 +/+) cells exposed to 0, 10 or 100 μM AZT, respectively. Values for centrosomal amplification were 18.0, 28.7 and 33.9 % for XPA −/− p53 +/+cells, and 21.6, 29.3 and 39.5% for XPA−/−p53 +/− cells, after exposure to 0, 10 and 100 μM AZT, respectively. For XPA−/−p53 −/− cells there were 18.4, 22.9 and 29.0% of cells with centrosomal amplification after exposure to 0, 10 and 100 µM AZT, respectively. Statistical analysis (by ANOVA) showed significance between each of the three transgenic groups, when compared to the wild type cells (p= 0.0025). The data suggest that loss of both XPA alleles confers genomic instability, but that additional loss of p53 does not further enhance instability. Whereas nucleotide excision repair is not considered to impact NRTI intracellular processing, these data would argue that lack of intact nucleotide excision repair enhances genomic instability in AZT-exposed cells. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2980.
Apparatus-dependent contributions to g − 2 and other phenomena

We consider the modification of the photon propagator for a system confined between two conducting plates. After a detailed discussion of the boundary conditions that apply in such a case, we calculate the change $\ensuremath{\Delta}g$ in the anomalous magnetic moment $g$ of the electron due to the plates. For both scalar and vector photons this is of order $\ensuremath{\Delta}g\ensuremath{\approx}\frac{\ensuremath{\alpha}\mathrm{ln}(2a\ensuremath{\Lambda})}{\mathrm{ma}}$, where $\ensuremath{\alpha}$ is the fine-structure constant, $m$ is the electron mass, $a$ is the plate spacing, and $\ensuremath{\Lambda}\ensuremath{\approx}1$ eV is the cutoff frequency above which the plates become "transparent" to photons. This correction to $g$ is near the threshold of what can be detected experimentally, and may suggest some difficulties in continuing attempts to compare higher-order predictions of QED with experiment. We also apply our results to discuss other novel phenomena, such as the regeneration of coherent kaons in the empty space between the plates.
The high‐resolution visible overtone spectrum of acetylenea)

Direct, gas‐phase overtone spectra of states corresponding to five and six quanta of C–H stretch have been obtained for four isotopically substituted acetylenes in the region 14 900–18 500 cm−1. Peak positions of individual rotation–vibration lines were determined to a precision of about 0.003 cm−1. A total of 39 bands are analyzed: 16 for 12C2H2; 14 for 13C2H2; five for 12C13CH2; and four for 12C2HD. The rotational structure of the bands is fit to a semirigid rotor Hamiltonian. However, the bands suffer from severe rotational perturbations, with typical matrix elements being on the order of 0.3 cm−1 or less. The error in the determined band origins varies between 0.001 and 0.1 cm−1, depending on the degree of perturbation. Precision rotational constants are also determined for the observed bands. The vibrational term values cannot be adequately explained in terms of the usual slightly anharmonic normal mode expansion. Even though acetylene represents an intermediate case between the local mode and normal...
Functional Capillary Beds in the Beating, KCl-Arrested and KCl-Arrested-Perfused Myocardium of the Dog

Dog hearts were taken without loss of blood under 3 different conditions: (1) normally beating hearts, (2) hearts that were arrested by potassium chloride for varying lengths of time and (3) potassium chloride-arrested hearts that were reperfused with blood after varying lengths of time. In normal hearts counts of open capillaries containing erythrocytes showed a uniform distribution throughout the right myocardium and a gradient decreasing from the epicardium toward the endocardium in the left myocardium. Potassium chloride-arrested hearts showed a reverse gradient in the left myocardium. In normal hearts, erythrocytes are oriented in capillaries so that their flat sides lie against the nearest myocardial cell. In the arrested hearts, one sees few or no erythrocytes with this orientation. The erythrocytes in the arrested hearts are swollen, rounded, or packed in clumps in the capillaries. Arrested hearts exhibit a weakening of the connective tissue elements of the myocardium, evident upon fixation or on perfusion of the myocardium with blood. The weakening increases as the length of myocardial arrest increases.
The use of biomarkers in the elderly: current and future challenges.

Biomarkers are hypothesized but not frequently used in research with the elderly because of a general paucity of supportive scientific data. However, there is an obvious need for greater diagnostic specificity and sensitivity across many diagnoses in the elderly, as well as good targets for therapeutic trials. The authors reviewed the available information in this field as part of a general review of geriatric research for the American Psychiatric Association. Potential biomarkers with pathophysiologic significance have been studied in the field of Alzheimer disease research with some success, especially in the area of genetic markers (apolipoprotein E [APOE] e4 allele), neuroimaging, and cerebrospinal fluid markers (beta-amyloid and tau). While some progress has been made in the search for adequate biomarkers in the elderly, in particular with Alzheimer disease, much more work is needed before these potential biomarkers can be reliably used in clinical practice.
Metallic photonic band-gap materials

We calculate the transmission and absorption of electromagnetic waves propagating in two-dimensional (2D) and 3D periodic metallic photonic band-gap (PBG) structures. For 2D systems, there is substantial difference between the {ital s}- and {ital p}-polarized waves. The {ital p}-polarized waves exhibit behavior similar to the dielectric PBG`s. But, the {ital s}-polarized waves have a cutoff frequency below which there are no propagating modes. For 3D systems, the results are qualitatively the same for both polarizations but there are important differences related to the topology of the structure. For 3D structures with isolated metallic scatterers (cermet topology), the behavior is similar to that of the dielectric PBG`s, while for 3D structures with the metal forming a continuous network (network topology), there is a cutoff frequency below which there are no propagating modes. The systems with the network topology may have some interesting applications for frequencies less than about 1 THz where the absorption can be neglected. We also study the role of the defects in the metallic structures.
Preparation of 6α- and 6β-carboxymethyl steroid conjugates and their use in radioimmunoassay for progesterone

Abstract A method was devised to utilize the Δ4-3-ketone structure of steroids to obtain a functional group at the 6 position which could be conjugated to proteins. The bis ethylene ketal of progesterone was formed and the resulting Δ5 double bond was subjected to epoxidation. The 5α,6α-epoxide formed was opened with allyl magnesium bromide after which the terminal carbon-carbon double bond was oxidized to provide a carboxyl group which could be coupled to the free amino groups of proteins. The 6α and 6β carboxymethyl progesterone derivatives formed by this method were coupled to bovine serum albumin (BSA) using tributyl amine and i -butyl chlorocarbonate. The 6α conjugate averaged 19 residues per molecule of BSA and the 6β, 24 residues per BSA. Antisera to the conjugates produced in rabbits showed very little cross-reaction with steroids which differed from progesterone at positions other than C-5 or C-6. There appeared to be very little difference between the specificities of the 6α and 6β antisera.
On π-shell photoionization in molecular nitrogen

Static-exchange calculations of π-shell photoionization in molecular nitrogen yield a physically incorrect description of the 1π_u → kπ_g partial-channel cross section; difficulties are attributed to spurious perturbations arising from the intense π → π^* intravalence transition. A simple projection procedure is devised that retains the computational simplicity of the frozen-core approximation and gives cross sections in good accord with measured values.
The use of focus as a tool for disambiguation of definite noun phrases

When speakers I utter or write sentences, they use certain words in the sentence to refer to people, places, object, times, events and ideas which exist in the real world. When sentences are formed into units of two or more sentences, certain words refer back to other referring expressions in' the previous sentences. Among the words which can be used to refer to the real world as well as to refer back (which is called the process of co-reference) are noun phrases containing a definite article, such as the (called defnps, hereafter). Several aspects of comprehension of defnps are open problems:
Hybridization between two oil-secreting orchids in South Africa

Natural hybrids among the specialized terrestrial oil-secreting orchids of South Africa are extremely rare even where multiple closely related species co-occur. We found putative hybrids between Pterygodium catholicum Sw. and P. acutifolium Lindl., two closely related oil-secreting orchids that lack morphological barriers to inter-breeding. The purpose of this study was to confirm the parentage of the putative hybrids using molecular data from one nuclear (ITS) and two plastid (matK-trnK and trnL/F introns) DNA regions. Phylogenetic analyses of sequences as well as nucleotide substitution patterns of the putative hybrids, putative parents, and their closest relatives were consistent with a hypothesis of hybridization. We suggest that the hybrids were the result of visits to both orchids by a single species of oil-collecting bee during a brief period of flowering overlap. These results suggest that the rarity of hybrids between these orchids is due to factors other than genetic incompatibility.
Spin squeezing with coherent light via entanglement swapping

We analyze theoretically a scheme that produces spin squeezing via the continuous swapping of atom-photon entanglement into atom-atom entanglement, and propose an explicit experimental system where the necessary atom-field coupling can be realized. This scheme is found to be robust against perturbations due to other atom-field coupling channels.
Cell motility and drug gradients in the emergence of resistance to chemotherapy

The emergence of resistance to chemotherapy by cancer cells, when combined with metastasis, is the primary driver of mortality in cancer and has proven to be refractory to many efforts. Theory and computer modeling suggest that the rate of emergence of resistance is driven by the strong selective pressure of mutagenic chemotherapy and enhanced by the motility of mutant cells in a chemotherapy gradient to areas of higher drug concentration and lower population competition. To test these models, we constructed a synthetic microecology which superposed a mutagenic doxorubicin gradient across a population of motile, metastatic breast cancer cells (MDA-MB-231). We observed the emergence of MDA-MB-231 cancer cells capable of proliferation at 200 nM doxorubicin in this complex microecology. Individual cell tracking showed both movement of the MDA-MB-231 cancer cells toward higher drug concentrations and proliferation of the cells at the highest doxorubicin concentrations within 72 h, showing the importance of both motility and drug gradients in the emergence of resistance.
Nonsyndromic congenital retinal nonattachment gene maps to human chromosome band 10q21.

Nonsyndromic congenital retinal nonattachment (NCRNA) comprises congenital insensitivity to light, massive retrolental mass, shallow anterior chamber, microphthalmia, and nystagmus. We searched for the location of the gene responsible for an autosomal recessive form of NCRNA by using DNA samples from 36 individuals from a founding population. To this end we applied homozygosity mapping and a DNA pooling strategy using genomewide screen polymorphic microsatellite markers. We used two DNA pools, one pool contained DNA from 16 individuals affected with NCRNA. The second pool contained DNA from 20 normal carrier individuals, the parents of the patients. The polymorphic microsatellite markers were polymerase chain reaction (PCR)-amplified in each DNA pool; the PCR products were electrophoresed on polyacrylamide gels and visualized by silver staining. The banding patterns from DNA pools of affected and unaffected persons were compared, and linkage was detected between the NCRNA and D10S1225, a marker in 10q21. To confirm linkage of NCRNA to chromosome 10q21 by homozygosity mapping, the patients and their carrier parents were genotyped for a number of other microsatellite polymorphic markers in the 10q21region. Statistically significant linkage was observed with multiple polymorphic markers in the 10q21 region. At θ = 0 with markers D10S1225, D10S1428, D10S1422, and D10S1418 maximum LOD scores of 3.74, 3.58, 3.79, and 3.48 were generated, respectively. TDT P values for markers D10S1225 and D10S1418 were 0.0000021 and 0.000021, respectively. Am. J. Med. Genet. 90:165–168, 2000. © 2000 Wiley-Liss, Inc.
Electronic Bombardment of Metal Surfaces

Secondary electrons from Cu, Ag, Au, W, Pt, Pd, Mg, and Al, produced by electronic bombardment, 0 to 250 volts.---The apparatus used to study the first six metals has been described in a previous ${\mathrm{paper}.}^{1}$ The last two metals and especially copper were studied with a modified apparatus constructed out of molybdenum so as to eliminate magnetic effects and permit the study of surfaces condensed from the vapor. (1) Curves are given showing the ratio of secondary (emergent) to primary (incident) electron current as a function of the primary velocity. These curves depend on the previous heat treatment of the metals, but after heating the higher melting point metals red-hot for some time, limiting curves were obtained which are characteristic of the different metals. Each curve (except for Cu) rises sharply from the origin but flattens out at a primary velocity of from 3 to 11 volts then rises more slowly showing perhaps a second tendency to flatten. Au and Ag also show a slight kink at 3 volts. The curve for Cu has two sharp maxima at 3 and 6.5 volts, respectively, with two other less distinct ones at about 14 and 20 volts. The secondary electron currents from Mg and Al were extraordinarily large in comparison with those of the other metals, the ratio to primary current for Al reaching a value of 1.8 at 140 volts. (2) Velocity distribution curves of the secondary electrons show that, in general, for low primary velocities, most of the secondary electrons have velocities nearly equal to the primary velocity. For higher primary velocities the percentage of secondary electrons having low velocities increases with the primary velocity. The primary velocity for which low velocity electrons begin to leave the surface varies somewhat with the metal but lies between 9 and 15 volts for the metals tested. Curves obtained with a special apparatus consisting of a conducting sphere at whose center the target was placed, show slight kinks indicating inelastic collisions in copper at 3 and 6.5 volts velocity, in agreement with the above maxima, but these results are somewhat doubtful. (3) Variation with the previous treatment of the copper surface. The results of various experiments show (a) that the removal of gas from the metal decreases the secondary current but does not change the form of the secondary electron curve, and (b) that the characteristic secondary electron curve with various maxima was obtained only from a crystalline surface after any amorphous layer present had been removed, and, within limits, was little affected by exposure to air. The effect of adding an evaporated film of copper was to decrease the secondary current very considerably and to cause the characteristic maxima to disappear. (4) Effect of simultaneous exposure to radiation from a quartz mercury arc was merely to add the photo-electric effect to that due to the bombardment.Effect on the surface of copper of heating in vacuum.---The results indicate that the layer deposited by evaporation is amorphous and that between certain limits of temperature surface crystals of copper are formed.
Old Age is an Institution

Corporations institutionalize managerial and professional positions in a hierarchical pyramid in which many young professionals begin work at a lower and wider level of the pyramid where positions are numerous. However, as the professionals start climbing up the pyramid in their careers, the number of positions rapidly declines at higher levels. The pyramid gets narrower as the professionals climb up into fewer and fewer positions. Since they usually either move up or out in their career climb, as the young professionals begin aging, more and more of them are forced out to look for jobs elsewhere or eventually, to retire. This article develops a simple model that shows how this particular way of organizing work results in premature retirement and aging for many workers. Alternative ways of organizing work are discussed in which premature aging and retirement do not take place. Furthermore, a number of implications are explored and various projections made all of which show that the so-called future crisis...
Contour and paired-point registration in a model for image-guided surgery.

Objectives/Hypothesis: This study assesses target registration error (TRE) of contour-based registration (CBR) and paired-point registration (PPR) for endoscopic sinus surgery. Study Design: The experimental registration model consisted of a replica of a human head (Sawbones #1345-27; Pacific Research Laboratories, Vashon, WA). Twelve surface fiducial markers were affixed to the simulated skin on the model, and titanium screws were placed in the regions of the anterior ethmoid (AE) and sphenoid face (SF). An axial computed tomography scan (1-mm slice thickness) was then obtained. Methods: Registration was then performed on the InstaTrak 3500 Plus (GE Surgical Navigation & Visualization, Lawrence, MA) with the standard PPR protocol with 12 points and CBR protocol with 500, 250, 125, 50, and 4 points. TRE was then calculated at the AE and SF targets. Results: Target registration error was significantly lower for paired-point registration compared with contour-based registration (AE, 0.5 mm vs. 1.5 mm, P <.0001; SF, 0.8 mm vs. 1.5 mm, P <.0001). Among contour-based registration protocols, target registration error at the sphenoid face was lowest with 50 points (1.5 mm, P <.02). At the anterior ethmoid, contour-based registration with 50 points produced a lower target registration error than contour-based registration with 125 points (1.5 vs. 1.8 mm, P <.01). Other target registration error values for CBR were similar at both regions. The target registration error interquartile range was lowest with CBR-125 at both regions. Conclusions: Paired-point registration provided significantly lower target registration error. Contour-based registration with 125 points (and possibly as few as 50 points) produces clinically acceptable target registration error. This registration model elucidates important concepts about registration for surgical navigation for sinus surgery.
Stories of night and dawn: Latin American women today

Abstract Latin America: surrounded by blue, intemperate and at times macabre oceans; enclosure of enormous mountain ranges, volcanos, glaciers, rivers, jungles; land of poets who have come from tiny little villages to reveal the secrets of their far-off regions and to sing of them to other men. Let us recall the rural school teacher, Gabriela Mistral, and Pablo Neruda, both from Chile, and Gabriel Garcia Marquez, of Colombia, who taught us that yellow butterflies are magical and that a woman hanging out sheets in the garden can indeed ascent to heaven. It is worth noting that all three of these writers were awarded the Nobel Prize for Literature in recent decades: Mistral in 1945; Neruda in 1971; and Garcia Marquez in 1982. Latin America's other winner of the Nobel Prize for Literature was Miguel Angel Asturias, of Guatemala, in 1967. All these splendid writers were from an area said to be Third World, said to be underdeveloped, or in the new parlance, ‘developing’. And then we have the other Latin America: a land of absences; of sudden deaths that never occur by accident; a continent of the ones who have disappeared; of the Madwomen of the Plaza de Mayo, the women who, for years now, gather every Thursday in the deserted Plaza de Mayo of Buenos Aires to weep, to scream and to beseech heaven and earth for news of their missing loved ones. Where is this Latin America? What is it really like?
Maternal Phenylketonuria International Collaborative Study revisited: evaluation of maternal nutritional risk factors besides phenylalanine for fetal congenital heart defects

Maternal phenylketonuria (MPKU) is known to affect fetal outcome, often being associated with microcephaly and congenital heart defects (CHD) if the maternal diet is not appropriately managed. We hypothesized that other nutrients aside from phenylalanine (Phe) may have significant effects on fetal outcome in MPKU pregnancies. The 416 pregnancies that resulted in live births reported in the Maternal PKU Collaborative Study (MPKUCS) were grouped according to whether or not the offspring were diagnosed with CHD. The groups were compared on first-trimester values of maternal data, including weight gain, plasma amino acids, protein and Phe intake, and red blood cell (RBC) folate. Patients were also grouped by first-trimester average blood Phe (≤910 μmol/L and >910 μmol/L) and then divided by total natural protein and medical food intake. The CHD group of 28 offspring had significantly higher blood Phe and lower proline, valine, methionine, isoleucine, leucine, lysine, arginine, and RBC folate. A significantly higher risk for CHD was found in the groups with lower natural protein and medical food intake, regardless of blood Phe levels. Insufficient natural protein and medical food product intake appears to be a risk factor for CHD independent of first-trimester plasma Phe levels. Low RBC folate and plasma methionine levels in the CHD group may suggest involvement of global DNA hypomethylation.
Cyclic deformation in Al-4wt.%Cu alloy single crystals containing coherent θ″ precipitates II: Dislocation microstructures

Abstract The dislocation structures of fatigued AlCu alloy single crystals containing θ″ precipitates have been investigated over the range of plastic shear strain amplitudes: 10−6 − 10−2. The cyclic stress-strain curve for this material is correlated with the dislocation structures. In that a two-phase type of structure, consisting of the matrix phase and the persistent slip bands (PSBs), has been observed, the cyclic deformation behavior of this material is broadly similar to that of pure metal. However, the structures of these phases are quite dissimilar from those in pure metals. The matrix contains a tangled mass of dislocation debris, and the structure of the PSBs is similar except that the dislocation density is higher on average and higher still at the interface with the matrix. Below the plateau of the cyclic stress-strain curve, no PSBs are observed. In the plateau, PSBs on the primary slip system, always of low volume fraction, carry the strain. At strain amplitudes higher than those of the plateau, PSBs exist on more than one system and intersect. No precipitate resolution was observed and cyclic softening is attributed to “precipitate disordering”. The localized strain in the PSBs is carried by combined slip processes, and the dislocation density remains roughly constant by dynamic equilibrium between dislocation multiplication and annihilation.
The effect of particle size distributions on the CRSS of aged NiAl alloys

Abstract The effect of the width of the γ′ particle size distribution on the CRSS of NiAl single crystals containing nominally 6 wt.% Al was investigated. The samples were given two-step aging treatments to produce broader unimodal distributions than those resulting from isothermal aging. The first aging treatments were done at 600 and 650°C for 488 and 69 hr, respectively, while the second were done at 625°C for various lengths of time. In all the samples the average particle size was nearly constant, but the standard deviation, σ, was increased by as much as 30%, primarily by the addition of smaller precipitates. After correcting for variations in the γ′ volume fraction introduced by these treatments, the effect of increasing σ was to reduce the CRSS of the samples by approx. 8%. This change, which is very small, is nevertheless substantially larger than that predicted by the computer experiments of Foreman and Makin. It is suggested that the discrepancies are due to the shortcomings of modelling real precipitate dispersions by arrays of point particles.
The determinants of the skill bias in Italy: R&D, organisation or globalisation?

In this study three possible determinants of the increase in the ratio between skilled and unskilled workers are tested together: R&D, organisational change, and foreign direct investment. After analysing the literature, these hypotheses are jointly tested using a SUR estimate. The results – regarding a panel of 488 Italian manufacturing firms over the period 1989–1997 – suggest the statistical significance of the impact of organisational change, while they tend to exclude a direct relation between R&D spending and skill upgrading. With reference to FDIs, the nature of the data and the results do not permit the exclusion of their possible influence.
Infiltrating lipoma of the chest wall.

CT, MR and bone scintigraphic findings of infiltrating chest wall lipoma are presented in this paper along with the differential diagnosis, clinical and surgical aspects of this lesion.
Vascular lesions in dermatomyositis

Extensive vascular lesions were found at necropsy in two childhood cases of dermatomyositis. Attention is drawn to the role of blood vessels in the pathogenesis of this disease and to the possible effect of steroid therapy on their development. Extense lesiones vascular esseva trovate al necropsia in duo casos de dermatomyositis in juveniles. Attention es appellate al rolo del vasos sanguin in le pathogenese de iste morbo e al possibile effecto de therapia a steroides super le disveloppamento del lesiones.
Cutting the forest to see a single tree

The development of single-molecule tools has significantly impacted the way we think about biochemical processes. Watching a single protein in action allows us to observe kinetic details and rare subpopulations that are hidden in ensemble-averaging techniques. I will discuss here the pros and cons of the single-molecule approach in studying ligand binding in macromolecular systems and how these techniques can be applied to characterize the behavior of large multicomponent biochemical systems.
Comparison of Radius-Estimating Techniques for Horizontal Curves

Techniques to obtain horizontal curve radii were identified and tested in a controlled experimental study. Ten techniques were identified and pilot tested. Eight of those initial 10 were then used to measure 18 horizontal curves on two-lane rural highways in Texas to evaluate fully their accuracy, precision, cost, ease of use, and safety. Statistically, all eight techniques produced equivalent accuracies, but they displayed a wide range in their precision. The costs varied as a function of the number of times each technique would be used in the field, with those techniques with high initial costs becoming more cost-competitive over the long run with many uses. Ease of use was gauged on the basis of the experience gained during this research. Safety was measured on the basis of whether a technique required personnel on the roadway or roadside or whether it allowed personnel to work from an office or inside a vehicle. The recommendations were based on the expected needs of three different groups that use radii information: transportation agencies, accident investigators, and transportation researchers. Within transportation agencies, engineers and planners in the office will probably benefit most from the plan sheet method, whereas field personnel will probably benefit most from using either the advisory speed or a Global Positioning System (GPS) method. Those who estimate only occasionally, such as accident investigators, will benefit most from the compass method. Finally, researchers or others who may have difficulty accessing plan sheets but still require accurate data will benefit from using a GPS.
De novo synthesis of potato spindle tuber viroid as measured by incorporation of 32P

Abstract Potato spindle tuber viroid (PSTV) was radioactively labeled during its synthesis in PSTV-infected tomato plants whose roots had been placed in nutrient solution containing [ 32 P]orthophosphate. The 32 P was incorporated into PSTV when the radioactive label was introduced into infected plants 2 weeks after inoculation, when systemic symptoms of PSTV started to appear. Synthesis of 32 P-labeled PSTV was not observed when 32 P was introduced into infected plants, either 1 or 3 weeks after inoculation. Uninoculated control plants subjected to incorporation of 32 P did not synthesize 32 P-labeled PSTV. De novo synthesis of 32 P-labeled PSTV, measured in a constant amount of the labeled low-molecular-weight RNA fraction, was higher in plants that incorporated the isotope for 2 days rather than 1 day and was similar in plants which incorporated 32 P for 2–5 days. The total amount of 32 P-labeled PSTV that was synthesized, however, increased with increasing time of incorporation. De novo synthesis of PSTV, compared with de novo synthesis of other RNAs, constituted 0.4% of the low-molecular-weight RNA and 0.08% of the total RNA extracted from tomato leaves. Infection with PSTV appreciably increased the synthesis of a low-molecular-weight RNA species that was larger than PSTV or 9 S RNA. Pure 32 P-labeled PSTV was obtained by electrophoresis of the low-molecular-weight RNA fraction on slab gels followed by reelectrophoresis of the extracted labeled PSTV on cylindrical gels. The G + C content of the homogeneous 32 P-labeled PSTV was 54.7 mol%.
Resistive-load detection in healthy school-aged children.

The ability to detect changes in respiratory resistance, which may be important in acute and chronic adaptations to airways obstruction, has not been measured previously in children. Two methods were used to measure the resistive-load detection thresholds (the added resistance that produced a “just noticeable difference” in perception) in a group of 38 healthy children and adolescents aged 7–16 years. Total respiratory system resistance (Rrs), as measured by forced oscillation, was used as an index of each child's intrinsic baseline (pre-test) resistance. To determine thresholds, a computer program added various percentages of baseline resistance according to response (first method) and then in random order (second method). Thresholds by at least one of the two methods were detectable in 32 of the children (84%), and failure to detect a threshold was less common in older than in young children. Thresholds obtained by each method were significantly related to one another (r = 0.54, P < 0.05). Baseline resistance accounted for a marginally significant proportion of the variation in thresholds as assessed by the tracking method (R2 = 0.12, P < 0.10) and a large proportion of the variation in thresholds as assessed by the random method (R2 = 0.66, P < 0.0001). Thresholds expressed in terms of percent of baseline resistance were found to have mean values of 100.4–105.0%, regardless of gender or age. Results from a comparison group of adults (n = 10) indicated lower threshold by both procedures (mean values, 71.90–76.50%). We conclude that perceptual thresholds for added resistive loads are determined, in part, by growth-related changes in intrinsic resistance. Pediatr Pulmonol. 1996; 22:357–363. © 1996 Wiley-Liss, Inc.
Distance, density, local amenities, and suburban development preferences in a rapidly growing East Tennessee county

Changing land-use patterns and amenity-driven migration have brought agriculture back into people’s lives, but there is a disconnection between the realities of production agriculture and romantic images attached to farming. To the extent that “rurality” is attached to farming, people may desire to live in rural places, but they may be unprepared for the realities of living near a working farm. Greater numbers of communities are facing “either/or” outcomes regarding the conversion of “open space” land to residential or commercial uses versus landscape preservation. This study explored the perceptions and preferences of a community regarding the conversion of a hypothetical parcel of open space to a working dairy or to a residential subdivision. Results suggest that the opportunity costs of foregoing open space for residential development are high, with implications for valuing the conservation of traditions that are tied to the land versus conversion of land solely for development purposes.
Tobacco-related diseases

Abstract Objective To provide an overview of the disease risks associated with cigarette smoking and the benefits of smoking cessation. Data sources Government reports and monographs, and research articles. Conclusion Cigarette smoking causes over 400,000 deaths per year and is a major cause of coronary heart disease, chronic obstructive pulmonary disease, and lung cancer. The disease risks associated with cigarette smoking are proportional to the intensity and duration of smoking. Cessation of cigarette smoking results in a decline in risk in relation to the risks of continuing smokers. Implications for nursing practice Clinicians must be aware of the magnitude of smoking-related risks and the benefits of smoking cessation as a critical intervention.
Lipopolysaccharide activates the sea urchin immune system

Profilin is a small, actin-binding protein that functions at the intersection of signal transduction and cytoskeletal modifications. Increases in the number of profilin messages per cell correlate with sea urchin coelomocyte activation in response to injury. Here we show that coelomocytes respond to immune challenge from lipopolysaccharide with significant elevations in profilin transcripts per coelomocyte.
Hypotheses for testing deviations from random integration: evidence for nonrandom retroviral integration.

Abstract The use of a recently developed in vitro model for retroviral integration provides a means of statistically testing hypotheses concerning the distribution of integration sites and hypotheses about the sequence of proviral orientations. In this study, three null hypotheses are formulated and applied to previously published data. Statistical analyses of these data suggest that the distribution of integration sites may not be uniform, and the sequence of proviral orientations is not random. On the basis of these results and the observed clustering of orientations, it was postulated that if a DNA sequence was involved in nonrandom proviral integration, that sequence would be found in the regions where the orientations change direction with respect to the target DNA (“I” regions). Computer analyses for homologous and complementary DNA sequences were performed on all possible pairs of indentiflable “I” regions. A common sequence (at least 8 bp in size) was found in three out of four regions and that sequence was absent elsewhere in the target DNA. A model, with features of recombination reminiscent of chi sequences in bacteria, is proposed that may account for these results.