cssi/SciSciGPT-SciSciNet huggingface dataset:
M1 macrophage polarization prevails in EBV infected children in an immuneregulatory environment

Macrophages can be polarized toward a proinflammatory phenotype (M1) (CD68+) or to an anti-inflammatory one (M2) (CD163+). Polarization can be triggered by cytokines such as IFN-γ for M1, or IL-10 and TGF-β, for M2. In the context of pediatric EBV infection, little is known about macrophage polarization in EBV primary or persistent infection. When studying tonsils of patients undergoing primary infection (PI), healthy carrier (HC), reactivation (R) and not infected (NI), M1 profile prevailed in all infection status. However, an increase in M2 cells was observed in those patients with broader expression of latency antigens, in particular EBNA2. Tonsils from primary infected patients showed an increased IL-10 expression, whereas, unexpectedly, TGF-β expression correlated with M1 marker. Furthermore, an inverse correlation was demonstrated between CD68 and IFN-γ. Therefore, in the context of asymptomatic infection in children, M1 macrophage polarization prevails, even in the presence of IL-10 and TGF-ꞵ immunomodulatory cytokines, and it might be independent from lymphomagenesis process. Our finding indicates that macrophages may have a significant plasticity in response to different types of extrinsic stimuli, and further studies are required to investigate M1 polarization under anti-inflammatory stimuli. Importance Most studies on EBV primary infection have been performed in adolescents and young adult populations with Infectious Mononucleosis (IM) in developed countries. Furthermore, studies related to macrophage polarization were assessed in EBV-associated lymphomas, but little is known about macrophage polarization in the context of primary infection at the site of viral entry and replication, the tonsils. Therefore, the aim of this study was to characterize macrophage response in children undergoing EBV primary or persistent infection, in order to enlighten the role of macrophages in viral pathogenesis, in a population with a high incidence of EBV-associated lymphomas in children younger than 10 years old. This study may contribute to explain, at least in part, the asymptomatic viral infection in children from an underdeveloped region, since M1 polarization pattern prevails, but in a regulatory environment.
Mutation of a new gene causes a unique form of Hermansky–Pudlak syndrome in a genetic isolate of central Puerto Rico

Hermansky–Pudlak syndrome (HPS) is a rare autosomal recessive disorder characterized by oculocutaneous albinism and a storage pool deficiency due to an absence of platelet dense bodies1,2,3. Lysosomal ceroid lipofuscinosis, pulmonary fibrosis and granulomatous colitis are occasional manifestations of the disease4. HPS occurs with a frequency of one in 1,800 in north-west Puerto Rico5 due to a founder effect6. Several non-Puerto Rican patients also have mutations in HPS17,8, which produces a protein of unknown function9. Another gene, ADTB3A, causes HPS in the pearl mouse10 and in two brothers with HPS-2 (refs. 11,12). ADTB3A encodes a coat protein involved in vesicle formation3,13, implicating HPS as a disorder of membrane trafficking. We sought to identify other HPS-causing genes7,8,14. Using homozygosity mapping on pooled DNA of 6 families from central Puerto Rico, we localized a new HPS susceptibility gene to a 1.6-cM interval on chromosome 3q24. The gene, HPS3, has 17 exons, and a putative 113.7-kD product expected to reveal how new vesicles form in specialized cells. The homozygous, disease-causing mutation is a large deletion and represents the second example of a founder mutation causing HPS on the small island of Puerto Rico. We also present an allele-specific assay for diagnosing individuals heterozygous or homozygous for this mutation.
Database Security 2000

Database systems are being more and more used, with larger sized databases, and as components of very complex systems, that include numerous protocols. Database security problems in the past have only partially been solved. Is there any hope to provide adequate security for the new database systems? This paper describes user and system requirements and provides a list of hints and techniques to better secure this type of system.
The Relationship between Economic Freedom and Socio - Economic Development

The aim of this paper is to determine if increased economic freedom leads to improvement in the quality of life. This paper will also examine how the rate of liberalization impacts the quality of life. This article is available in The Park Place Economist: http://digitalcommons.iwu.edu/parkplace/vol10/iss1/20
Sarcoplasmic Reticulum III. THE ROLE OF PHOSPHOLIPIDS IN THE ADENOSINE TRIPHOSPHATASE ACTIVITY AND Ca++ TRANSPORT

Abstract Treatment of skeletal muscle microsomes with phospholipase C inhibits the adenosine triphosphatase activity and calcium transport, parallel with the selective hydrolysis of membrane lecithin. The ATPase activity of phospholipase C-treated microsomes is reactivated by synthetic lecithin, lysolecithin, phosphatidic acid, and nonionic and anionic detergents. The reactivation of the calcium transport of phospholipase C-treated microsomes requires lecithin, lysolecithin, or phosphatidic acid. Detergents are ineffective. The activating effect of phospholipids on the ATPase activity and calcium transport is accompanied by tight binding of phospholipids to the microsomal membrane.
Effect of Acetazolamide and Cholecystokinin on the Secretion of Pepsin from Histamine-Stimulated Heidenhain Pouches

Summary Pepsin output from Heidenhain pouches was studied during steady states of acid secretion under submaximal histamine stimulation. A small but sustained output of pepsin was observed. Inhibition of acid output and volume rate of flow by acetazolamide and cholecystokinin during continuous histamine stimulation was accompanied by significant increases in pepsin output. These results are similar to those reported for large doses of gastrin. Reduction in the volume rate of flow and acid output induced by lowering the stimulatory dose of histamine was not accompanied by an increase in pepsin output.
Management of orthostatic hypotension

The pathogenesis, clinical manifestations, and management of orthostatic hypotension (OH) are reviewed. OH is a decline in blood pressure that occurs when one moves from a lying to a standing position that results in symptoms of cerebral hypoperfusion, most commonly lightheadedness and syncope. The disorder may result from primary autonomic disorders, such as Shy-Drager syndrome; reversible nonautonomic causes, such as reduced blood volume; underlying diseases, such as diabetes mellitus; and drugs. Elderly people are predisposed to OH. The diagnosis of OH is based on the documentation of postural hypotension accompanied by symptoms of cerebral ischemia. The goal of therapy is to relieve symptoms. Nonpharmacologic approaches are preferred and include increasing sodium intake, avoiding rapid postural changes, and wearing elastic garments. OH is difficult to treat pharmacologically because of varying responses and adverse effects. The drug of choice for all types of OH is fludrocortisone acetate, although caution must be used in patients with congestive heart failure. Prostaglandin synthetase inhibitors can also be used for all types of OH but have had more limited success. Sympathomimetics with or without monoamine oxidase inhibitors, beta-adrenergic antagonists, and ergot alkaloids should be administered only to patients with certain types of OH, and patients must be monitored closely. Clonidine, midodrine, yohimbine, octreotide, dopamine antagonists, desmopressin, and epoetin alfa have not been well studied and should be limited to patients with severe, refractory disease. Although no uniformly effective treatment regimen exists, OH can often be adequately managed with a combination of nondrug and drug therapies.
Medical therapy reduces microbiota diversity and evenness in surgically recalcitrant chronic rhinosinusitis

Background Chronic rhinosinusitis (CRS) is a highly prevalent and heterogeneous condition frequently treated with antibiotics and corticosteroid therapy. However, the effect of medical therapy on sinus microbiota remains unknown. Methods We enrolled CRS patients (n = 6) with patent maxillary antrostomies and active mucosal inflammation, who had not received antibiotics or corticosteroids in the previous 8 weeks. A pretreatment and posttreatment maxillary sinus swab was collected, from which DNA was extracted, pyrosequenced, and analyzed using a naive Bayesian classifier and ecological analyses. Results Four patients showed significant improvement in endoscopic appearance. The shifts in microbiota in response to therapy were highly individualized. There was no single common microbiota profile among patients with similar clinical outcomes, but overall there was significant decrease in microbiota diversity (t(5) = 2.05, p = 0.10) and evenness (t(5) = 2.28, p = 0.07) after treatment. Conclusion Our findings strongly correlate with earlier studies that examined the impact of antibiotics on human microbiota. We observed that posttreatment, patients frequently became colonized by taxa that are less susceptible to the prescribed antibiotics. Our findings highlight the challenge in seeking generalizable diagnostic and therapeutic options in CRS, particularly regarding microbiological response and outcomes.
Sensitivity analysis of a simulation model of methane flux from the Florida Everglades

Abstract To determine parameters having the greatest influence on methane flux, I developed a 7-compartment, 4-layer model of methane production in the Florida Everglades. The four layers consist of a bottom sediment layer, a top, active sediment layer, an algal-mat layer, and an overlying water layer. The compartments are acetate (a major end product of anaerobic decomposition), sulfate-reducing and methane-producing bacteria (major competitors for acetate), sulfate, methane, methane-oxidizing bacteria, and oxygen. Acetate production, depth of the active sediment layer, diffusion rate of oxygen into the sediment, and methane oxidation rate had the greatest influence of methane flux. A two-way sensitivity analysis showed that a change in one of these parameters could enhance or diminish the influence of another. Acetate production was the most sensitive parameter; as it increased, the rate of methane flux increased. Increased oxygen diffusion or methane oxidation diminished the effect of acetate production. Increased depth of the active sediment layer enhanced the effect of acetate production. As depth increased, the amount of acetate produced per area increased, increasing methane production and methane flux. At depths greater than 0.22 m, methane flux asymptotically tapered off. The increased depth increased the distance over which methane must diffuse. This constrained the amount of methane flux from the system. At shallow depths, increased oxygen diffusion and methane oxidation produced significant changes in methane flux. With increasing depth, the influence of these parameters became insignificant. This was attributed to the smaller contribution of oxygen diffusion to the larger volume of sediment, which constrained oxygen concentration and thus methane oxidation.
An assemblage of salamanders in the southern Appalachian Mountains revisited : Competitive and predatory behavior?

Salamander communities have been excellent model systems for investigating the effects of competition and predation on community structure. Researchers have frequently examined the roles of competition and predation in terrestrial or semi-aquatic communities of salamanders, but have rarely examined the influence of these factors between these communities. We conducted mesocosm and laboratory behavioral experiments (1) to test hypotheses, derived from by a previous laboratory study, in a semi-natural setting and (2) to formulate new hypotheses regarding novel species-pair combinations. Our mesocosm experiments did not support a previous hypothesis of predation by Desmognathus fuscus (a semi-aquatic species) on Plethodon cinereus (a terrestrial species), but did support a prediction that P. cinereus would avoid D. fuscus. We predicted that behavioral experiments between pairs of semi-aquatic species would demonstrate predatory behavior by D. fuscus toward E. cirrigera and aggressive behavior by D. ochrophaeus toward Eurycea cirrigera; we did not find strong evidence for either predation or aggression. This finding was surprising given the similar activity patterns and dietary habits of these species. Although we predicted that Desmognathus might influence local distributions of heterogeneric salamanders through interspecific aggression in a manner similar to that seen within this genera, we found that both D. fuscus and D. ochrophaeus displayed much less aggression than expected. However, D. fuscus, in particular, appears to induce avoidance behavior in both P. cinereus and E. cirrigera without evidence of predation or excessive aggression, indicating that interference competition may be an important factor in structuring plethodontid communities.
Managing the chronic, treatment-resistant patient with anorexia nervosa.

Objective To describe the psychopathology of chronic, treatment-resistant anorexia nervosa, as well as a paradigm for its clinical management. Method The foundation of the approach integrates clinical experience, empirical psychological findings, and a conceptual understanding of developmental and phenomenologic aspects of the illness. Results Elements of the management paradigm take account of the compensatory nature of illness chronicity. The inherent risks of treating these patients in the customary way are described, along with therapist countertransference that must be anticipated and effectively considered. Discussion The chronically ill patient requires a unique approach to care, one that minimizes the risk of iatrogenic effects of rapid weight restoration or failure to appraise the deleterious influences of therapist countertransference. © 2004 by Wiley Periodicals, Inc. Int J Eat Disord 36: 245–255, 2004.
Phase stability relationships and glass formation in the system Cu-Ag-In

Details are presented of phase relationships in the ternary system Cu-Ag-ln. Isothermal sections have been determined at 505 and 676 °C, and a most likely projected surface of primary crystallization is proposed. The phase relationships in this system are dominated by an extensive γ-phase (a Hume-Rothery “electron phase”) which extends approximately along a line of 30 at. pct In between the respective binary phases. The stability of the γ-phase follows approximately constant electron concentration lines and appears to be also enhanced by size relationships in the ternary system. The glassforming ability (GFA) in the Cu-Ag-ln system is poor, being limited to only a narrow region in the vicinity of alloy Cu51Ag31In18. This behavior appears to be directly related to the stability of the γ-phase. An attempt has been made to interpret the GFA in terms of the most likely behavior of the T0 surfaces.
Characterization of repetitive sequence families in mouse heart small polydisperse circular DNAs: age-related studies

Using alkaline denaturation-renaturation, exonuclease III digestion and density gradient centrifugations, we have isolated covalently closed circular DNA (cccDNA) molecules from 1-, 8-, 16-, and 24-month C57BL/6 mouse heart tissues. Electron microscopic analyses demonstrated that all these preparations contained small polydisperse circular DNAs (spcDNAs). spcDNAs showed similar size distributions at all ages, but more discrete size classes and slightly larger circles were observed in the 24-month heart spcDNA preparations. Based upon the final yields of spcDNAs, there appeared to be no age-related changes in the quantity of these circular molecules in vivo. Furthermore, [3H]-pBR322 recovery studies revealed no endogenous factors that might have affected the yield of spcDNAs from young and old tissues. To determine if there were any age-related changes in the quantity of repetitive sequences in spcDNAs, we probed heart spcDNAs with B1, B2, IAP, L1 and satellite sequences of the mouse genome. The hybridization results showed that these sequence families were differentially represented at all ages in spcDNAs. B2 sequences were the highest across all the age groups while L1 sequences were the lowest. The quantity of B1-, B2-, IAP-, and L1-spcDNAs appeared to decrease at 24-months. Satellite sequences appeared to decrease from 1-month to 8-months, but no change beyond 8-months.
Feshbach resonances in electron–molecule scattering by the complex multiconfiguration SCF and configuration interaction procedures: The 1Σ+g autoionizing states of H2

The complex resonance energies (positions and widths) and wave functions for the lowest 1Σ+g doubly excited autoionizing states of H2 are directly computed by using the multiconfiguration self‐consistent field (MCSCF) method and the configuration interaction (CI) method within the context of the complex basis function technique. These autoionizing states are Feshbach resonances (as opposed to shape resonances), and single‐configuration self‐consistent field calculations provide no information about the lifetimes of such states. All of these methods rely on the existence of a complex variational principle for complex resonance energies. It is shown that by using a small orbital space the MCSCF method can give essentially the same complex energies as the full CI method. Numerical results are in good agreement with previous theoretical results, especially with the optical potential calculation employing a diffuse basis set by Schneider and Collins [Phys. Rev. A 28, 166 (1983)], indicating that poor agreement...
The School System as a Post-Fordist Organization: Fragmented Centralization and the Emergence of IT Specialists

This article explores organizational restructuring in one large public institution as a situated response to the instabilities brought on by globalization. Drawing upon ethnographic research with the Los Angeles public school system, I argue that a process of fragmented centralization is taking place, whereby decision-making authority is becoming more centralized while accountability for centrally made decisions is becoming more distributed. This process is propelled, in part, by the rise of a new occupational group of information technology (IT) specialists that is integrating itself into places of power and altering all aspects of organizational operations, transforming the school system into a post-Fordist organization.
KNL1/Spc105 recruits PP1 to silence the spindle assembly checkpoint.

Summary The spindle assembly checkpoint (SAC) delays anaphase onset until kinetochores accomplish bioriented microtubule attachments [1]. Although several centromeric and kinetochore kinases, including Aurora B, regulate kinetochore-microtubule attachment and/or SAC activation [2–4], the molecular mechanism that translates bioriented attachment into SAC silencing remains unclear [5]. Employing a method to rapidly induce exact gene replacement in budding yeast [6], we show here that the binding of protein phosphatase 1 (PP1/Glc7) to the evolutionarily conserved RVSF motif of the kinetochore protein Spc105 (KNL1/Blinkin/CASC5) is essential for viability by silencing the SAC, while it plays an auxiliary nonessential role for physical chromosome segregation. Although Aurora B may inhibit this binding, persistent PP1-Spc105 interaction does not affect chromosome segregation and is insufficient to silence the SAC in the absence of microtubules, indicating that dynamic regulation of this interaction is dispensable. However, the amount of PP1 targeted to kinetochores must be finely tuned, because recruitment of either no or one extra copy of PP1 to Spc105 is detrimental, illustrating the vital impact of targeting an exiguous fraction of PP1 to the kinetochore. We propose that the PP1-Spc105 interaction enables local regulation of dynamic phosphorylation and dephosphorylation at the kinetochore to couple microtubule attachment and SAC silencing.
Linear representations of projective planes in projective spaces

Abstract A linear representation (LR) of a projective plane π (Desarguesian or not) is an isomorphic imbedding of π in a (Desarguesian) projective space ∑, in which each point or line of π becomes a nonempty, finite-dimensional projective subspace of ∑, and incidence is given by the containing relation of ∑. The paper begins an axiomatic study of LR's. At one end of the scale, every finite projective plane with exactly v lines has a “nondense” LR with ∑ of dimension v . Towards the other end of the scale, every translation plane which is suitably “finite-dimensional” has a “dense” LR with properties close to the lattice-structure of ∑. A theory of “switching-sets” is given, by which new translation planes can be derived from old. The paper generalizes an earlier one of the authors. (The construction of translation planes from projective spaces, J. Algebra 1 (1964), 85–102.)
Internal Medicine Clerkship Directors’ Perceptions About Student Interest in Internal Medicine Careers

Background Experienced medical student educators may have insight into the reasons for declining interest in internal medicine (IM) careers, particularly general IM.
Light-driven water oxidation for solar fuels

Abstract Light-driven water oxidation is an essential step for conversion of sunlight into storable chemical fuels. Fujishima and Honda reported the first example of photoelectrochemical water oxidation in 1972. In their system, TiO 2 was irradiated with ultraviolet light, producing oxygen at the anode and hydrogen at a platinum cathode. Inspired by this system, more recent work has focused on functionalizing nanoporous TiO 2 or other semiconductor surfaces with molecular adsorbates, including chromophores and catalysts that absorb visible light and generate electricity (i.e., dye-sensitized solar cells) or trigger water oxidation at low overpotentials (i.e., photocatalytic cells). The physics involved in harnessing multiple photochemical events for multi-electron reactions, as required in the four-electron water-oxidation process, has been the subject of much experimental and computational study. In spite of significant advances with regard to individual components, the development of highly efficient photocatalytic cells for solar water splitting remains an outstanding challenge. This article reviews recent progress in the field with emphasis on water-oxidation photoanodes inspired by the design of functionalized thin-film semiconductors of typical dye-sensitized solar cells.
Strength and electrical conductivity of a deformation-processed Cu-5 Pct Nb composite

A Cu-5 pct Nb alloy was deformation processed by wire drawing to very large reductions (99.9993 pct) and the strength and electrical conductivity properties compared with similarly deformation processed Cu-20 pct Nb. The results showed that the Cu-5 pct Nb alloy was transformed into a composite material with the original Nb dendrites becoming ribbonlike filaments in a similar fashion to higher Nb-containing Cu-Nb alloys. The degree of strength increase with increasing deformation processing greatly exceeds rule-of-mixtures expectations at higher degrees of deformation processing, where the Nb becomes highly aligned with the wire axis. A 5 pct Nb addition appears to contain close to the minimum amount of Nb phase necessary to produce appreciable strengthening during deformation processing of Cu-Nb alloys. The strength-conductivity properties of the deformation-processed Cu-5 pct Nb alloy show significant improvements in strength over the best commercial alloys in the conductivity range of 80 to 90 pct international annealed copper standard (IACS).
Interactive Journey Through the Innerbody Web Site

Innerbody.com is a commercial, educational Web site designed for anyone interested in learning the intricacies of the human anatomy. It provides an interactive journey through the ten systems of the human body using tutorials, animations, diagrams, and descriptive links.
Characterization of T cell growth factors for the clonal analysis of recognition properties of T cells.

Helper T cells activated to select erythrocyte antigens exhibit both antigen-specific and nonspecific effects on the induction of in vitro antibody synthesis. White specific helper function requires the interaction of antigen with antigen-binding receptors on T cells, factors released as a consequence of this interaction most likely give rise to the nonspecific bystander effects observed. Helper T cells also display specificity in cellular interactions. In chimeric mice constructed by a graft of one parental strain thymic tissue on athymic F1 (C57BL/6 × BALB/c) mice, the F1 T cells that mature provide helper activity for B cells that are H-2 compatible with the graft donor. A T cell growth factor (TCGF)† has been characterized that has helper T cell-replacing properties in the induction of in vitro immune responses. TCGF appears to exert its effects via the clonal expansion of antigen-activated T cells present in these cultures. The T cell-growth promoting properties of TCGF have been used to establish continuous cultures of proliferating helper T cells. Thus, by utilizing F1 thymus-chimeric mice to select for cellular recognition specificities in T cells followed by antigen-activation of T cells to render them responsive to TCGF, we hope to generate clones of helper T cells from a common genetic background to analyse the biochemical nature of their recognition structures.
Predictors of local adverse effects caused by topical tretinoin cream 0·1% in the Veterans Affairs Topical Tretinoin Chemoprevention trial

SummaryBackground Topical tretinoin is commonly prescribed, but its frequent adverse effects are barriers to use. Predictors of resistance or susceptibility to retinoid irritation are not known. Objective To identify baseline patient characteristics associated with adverse effects of topical tretinoin. Methods This cohort study used data collected from 324 participants in the Veterans Affairs Topical Tretinoin Chemoprevention trial who were randomized to apply tretinoin cream on the face and ears. Univariate and multivariate logistic regression models were used to examine the associations between baseline characteristics and local adverse effects. Results One hundred and ninety-seven patients (61% of those randomized to tretinoin) reported local adverse effects within 6 months. Clinical signs of severe photodamage at baseline [odds ratio (OR) 0·15, 95% confidence interval (CI) 0·04–0·54] and history of acne (OR 0·46, 95% CI 0·27–0·77) were associated with a decreased risk of adverse effects to tretinoin. The use of other topical medications at enrolment (OR 1·88, 95% CI 1·15–3·08) predicted an increase in adverse effects. Conclusions In this study population, the common indications of topical tretinoin treatment were associated with lower risks of adverse effects. The concurrent use of other topical medications may worsen irritation caused by tretinoin.
Infrared thermography (IRT) and ultraviolet fluorescence (UVF) for the nondestructive evaluation of ballast tanks' coated surfaces

Abstract This paper quantifies the detectability limits of infrared thermography (IRT) and ultraviolet fluorescence (UVF) techniques in the thickness measurements of the naval protective coatings applied on ship ballast tanks. The change in signal per unit thickness (25 μm) is used to describe each technique resolution, when using a pulsed-thermographic procedure and a UVF spectroscopic analysis. Furthermore, Tanimoto criterion in addition to a local signal-to-noise ratio (SNR) computation measure the revealability of pinholes, the IRT technique provides an 83% revealability while the UVF imaging has a 66% value. The goal of this work is to benchmark the novel UVF approach against that of the IRT procedures.
Preliminary classification of some naturally occurring hydroxycinnamic acids through their ultraviolet spectra.

Abstract A technique is suggested for preliminary classification of plant extracts into any of the several hydroxycinnamic acid classes, as free acids or esters, by means of characteristic changes in absorption spectra in acid, alkaline, and ethanolic solvents.
Nonlinear Stability through Algebraically Decaying Point Spectrum: Applications to Nonlocal Interaction Equations

Nonlocal interaction equations, such as aggregation equations and a number of related models for biological swarming, can exhibit compact, co-dimension one equilibrium solutions. Nonlinear stability of these solutions crucially depends on understanding the properties of operators whose linearizations have point spectrum that accumulates on the imaginary axis. In this paper, we establish criteria upon the linear operator, the nonlinearity, and the admissible perturbations under which linear stability is sufficient to guarantee nonlinear stability in the presence of such algebraically decaying point spectrum. We also provide temporal rates at which admissible perturbations decay to zero. We then apply the theory to some simplified nonlocal equations.
Similarities in the Age-Specific Incidence of Colon and Testicular Cancers

Colon cancers are thought to be an inevitable result of aging, while testicular cancers are thought to develop in only a small fraction of men, beginning in utero. These models of carcinogenesis are, in part, based upon age-specific incidence data. The specific incidence for colon cancer appears to monotonically increase with age, while that of testicular cancer increases to a maximum value at about 35 years of age, then declines to nearly zero by the age of 80. We hypothesized that the age-specific incidence for these two cancers is similar; the apparent difference is caused by a longer development time for colon cancer and the lack of age-specific incidence data for people over 84 years of age. Here we show that a single distribution can describe the age-specific incidence of both colon carcinoma and testicular cancer. Furthermore, this distribution predicts that the specific incidence of colon cancer should reach a maximum at about age 90 and then decrease. Data on the incidence of colon carcinoma for women aged 85-99, acquired from SEER and the US Census, is consistent with this prediction. We conclude that the age specific data for testicular cancers and colon cancers is similar, suggesting that the underlying process leading to the development of these two forms of cancer may be similar.
Thermogravimetry coupled to single photon ionization quadrupole mass spectrometry: a tool to investigate the chemical signature of thermal decomposition of polymeric materials.

Mass spectrometry (MS) is an established analytical technique to analyze evolved gas in thermogravimetry (TG). In this study, for the first time a novel SPI-MS technique using an electron beam pumped VUV excimer lamp as photon source (λ = 126 nm) was employed in conjunction with thermogravimetry. The coupling was achieved with an improved heated interface and adjacent transfer capillary between TG and ion source of a quadrupole mass spectrometer. The feasibility of this approach was proven by investigating semivolatile substances such as long-chain alkanes (heptadecane C17H36), polymers, e.g., polystyrene, polycarbonate, and acrylonitrile−butadiene−styrene, polymer mixtures and blends. Mass spectra with almost no fragmentation were obtained, and quantification of selected substances could be achieved. Polymer mixtures could be distinguished by their SPI mass spectra, and the effect of premixing of polymers has been accessed. Its unique attributes render the TA-SPI-MS method a promising new tool for quanti...
Use of Eigenslope to Estimate Fourier Coefficients for Passive Cable Models of the Neuron

Boundary conditions for the cable equation—such as voltage-clamped or sealed cable ends, branchpoints, somatic shunts, and current clamps—result in multi-exponential series representations of the voltage or current. Each term in the series expansion is characterized by a decay rate (eigenvalue) and an initial amplitude (Fourier coefficient). The eigenvalues are determined numerically and the Fourier coefficients are subsequently given by the residues at the eigenvalues of the Laplace transform of the solution. In this paper, we introduce an alternative method for estimating the Fourier coefficients which works for all types of boundary conditions and is practical even when analytic expressions for the Fourier coefficients become intractable. It is shown that terms in the analytic expressions for the Fourier coefficients result from derivatives of the equation for the eigenvalues, and that simple numerical estimates for the amplitude coefficients are easily derived by replacing analytical derivatives by numerical eigenslope. The physical quantity represented by the slope is identified as effective neuron capacitance. © 1997 John Wiley & Sons, Ltd.
The isotopic composition of magnesium nuclei in solar flares

The isotopic ratio /sup 26/Mg//sup 24/Mg = 0.13 +- 0.04 has been obtained from satellite measurements of nuclei accelerated to 35--55 MeV per nucleon in 10 solar flares occurring in the period 1974--1979. This ratio is in agreement with solar system compilations based on terrestrial and meteoritic samples. This result indicates that the observed difference of a factor of approx.2 in the ratio /sup 22/Ne//sup 20/Ne between solar flare measurements ( = 0.13 which agrees with the ratio for neon-A in meteorites) and measurements in the solar wind ( = 0.074) is not likely to be due to mass biasing effects in normal solar flares.
RECONSIDERING THE OCAMPO CAVES AND THE ERA OF INCIPIENT CULTIVATION IN MESOAMERICA

In northeastern Mexico, near Ocampo, Romero’s and Valenzuela’s caves have been central to explanations of agricultural origins in Mesoamerica for more than four decades. Along with caves in Tehuacan and Oaxaca, these "Ocampo caves" have provided almost all of the available evidence for the initial appearance of a number of key Mesoamerican crop plants, including maize, beans, and squash. This article reanalyzes the cultural and temporal context of five crop plant assemblages in the Ocampo caves: maize (Zea mays), bottle gourd (Lagenaria siceraria), and three species of squash (Cucurbita argyrosperma, C. moschata, C. pepo). Fifteen AMS radiocarbon dates on early domesticates both confirm the stratigraphic integrity of the two caves and substantially revise the temporal framework for initial appearance of core domesticates in northeastern Mexico, showing the transition to food production in Tamaulipas took place more recently than previously thought. A substantially foreshortened chronology for Ocampo crop plants confirms the northern periphery role of Tamaulipas in the origins of agriculture in Mexico, while also underscoring the need for establishing AMS-based archaeobotanical sequences across Mesoamerica to gain an adequate context for understanding the temporal, environmental, and cultural contexts of initial plant domestication in the region.
Fossil track and thermoluminescence studies of Luna 16 material

Measurements of track densities and thermoluminescence have been made on two 5-mg samples (feldspar crystals) from the Luna 16 core tube. The distribution of track densities is shown graphically and is similar to that observed in heavily irradiated Apollo samples. Results of thermoluminescence measurements are plotted and also compared with similar measurements of Apollo samples.
Trocar site closure: a new and easy technique.

ABSTRACT The GORE™ (W.L. Gore & Associates, Phoenix, AZ) Suture Passer, a new reusable fascial closure device, is one of the best devices on the market for closure of laparoscopic trocar site wounds. The technique for closure of fascia using this device is described. It is a cost-effective, safe, and easy.
Operational social systems modeling: Pitfalls and prospectives

As myriad social problems press for attention and resolution, a variety of individuals have joined the search for means to understand and manage those problems. An important component of the search is the use of analytic methods and models, which are being relied on to a large and unprecedented extent. Social systems modeling appears to have a future of both high potential and growth. However, as is the case with many emerging and evolving fields, operational or applied social modeling has had its share of failures and only limited successes, and it will undoubtedly continue to do so. This essay concentrates on what appear to be several of the key, unresolved problems impeding full and productive use of these methods and techniques. It is both a summary assessment of experiences to date and a blueprint for work yet to be done.
Optical and electronic simulation of gallium arsenide/silicon tandem four terminal solar cells

Abstract A tandem solar cell in a mechanical (stack like) arrangement of gallium arsenide and silicon solar cells is evaluated as a pathway towards higher efficiency terrestrial solar cells. In this work the technical feasibility of the tandem solar cell is investigated. Here we report on detailed electrical and optical simulations of this structure quantifying various theoretical and practical loss mechanisms in the interface and in the device and indicate that an efficiency improvement of 5.13% would be attainable with the present generation of gallium arsenide and silicon solar cells in this configuration. The optical and electrical parameters for gallium arsenide and silicon simulation models were extracted from experimental devices and material vendors. The developed simulation models were validated by comparing the performance of standalone gallium arsenide and silicon solar cells with experimental devices reported in the literature.
EFFECTS OF SURGICAL HYPOPHYSECTOMY IN A MAN WITH MALIGNANT MELANOMA

MALIGNANT melanoma in man displays a number of features which suggest that its development and growth may be related to or influenced by the endocrine system. Melanomas are almost never malignant before puberty, are not observed in castrated individuals, and their growth and dissemination are markedly accelerated during puberty and during pregnancy (1, 2). The clinical course of melanoma with metastases is uncompromising in its inexorable progress and cannot be modified by any presently known methods. Attempts to influence the neoplasm by castration, androgenic or estrogenic therapy have been unsuccessful. Pack and Scharnagel (3) performed bilateral adrenalectomy on two occasions without beneficial effects. Wigby and Metz (4) reported a patient with disseminated melanoma who had striking regression of subcutaneous and visceral metastases of melanoma following roentgen irradiation of the pituitary gland with approximately 4,500 r. No effects were observed, however, in 4 additional patients treated in this ...
Determination of bond dissociation energies using electrospray tandem mass spectrometry and a derived effective reaction path length approach.

A new approach for calculating bond dissociation energies (BDEs) from ES-MS/MS measurements has been developed. The new method features a “derived effective reaction path length” that has been applied to measure BDEs of alkali metal (Li+) adducts and halide (Cl-) adducts of monoacylglycerol, 1,2-diacylglycerol, and 1,3-diacylglycerol lipids. Also studied were lithium-bound dimers of monoacylglycerols, 1,2-diacylglycerols, and 1,3-diacylglycerols. BDEs for the adducts and dimers of the lipids were derived from collision-induced dissociation experiments using a triple quadrupole mass spectrometer with electrospray as the ionization source. Mass spectral data were used to empirically derive a single-exponential growth equation that relates product cross section to collision energy. From these single-exponential equations, a general second-order polynomial was derived using a multivariate growth curve model that enables prediction of BDEs of unknown complexes. Mass spectral results were compared to computer-g...
Aircraft Control-Display Analysis and Design Using the Optimal Control Model of the Human Pilot

The use of the optimal control model (OCM) of the human pilot as a design tool is discussed. A novel procedure for the assignment and selection of model parameters in the absence of experimental data is proposed. A technique for partitioning a weakly coupled, multiaxis task into approximate state-uncoupled, single-axis tasks is introduced. The resulting modeling technique is utilized in the design and analysis of an aircraft flight-director system. This flight-director design technique differs from previous related work using the OCM in that considerable effort is devoted to ensuring that the OCM-designed director exhibits the desirable frequency-domain characteristics associated with experimentally verified classical designs (e.g., K/s "effective vehicle" characteristics, noninteracting controls, etc.). The implications of the technique in the design of automatic flight control systems which employ the human pilot as a performance assessor and failure detector are briefly discussed.
Homopolymeric tracts represent a general regulatory mechanism in prokaryotes

Background While, traditionally, regulation of gene expression can be grouped into transcriptional, translational, and post-translational mechanisms, some mechanisms of rapid genetic variation can also contribute to regulation of gene expression, e.g., phase variation.
Aural browsing on-the-go: listening-based back navigation in large web architectures

Mobile web navigation requires highly-focused visual attention, which poses problems when it is inconvenient or distracting to continuously look at the screen (e.g., while walking). Aural interfaces support more eyes-free experiences, as users can primarily listen to the content and occasionally look at the device. Yet, designing aural information architectures remains a challenge. Specifically, back navigation is inefficient in the aural setting, as it forces users to listen to each previous page to retrieve the desired content. This paper introduces topic- and list-based back: two navigation strategies to enhance aural browsing. Both are manifest in Green-Savers Mobile (GSM), an aural mobile site. A study (N=29) compared both solutions to traditional back mechanisms. Our findings indicate that topic- and list-based back enable faster access to previous pages, improve the navigation experience and reduce perceived cognitive load. The proposed designs apply to a wide range of content-intensive, ubiquitous web systems.
Mixture Analysis Using a Quadrupole Mass Filter/Quadrupole Ion Trap Mass Spectrometer

A hybrid tandem mass spectrometer is constructed by interfacing a quadrupole mass filter (Q) to a quadrupole ion trap mass spectrometer (QITMS) and is evaluated for the analysis of mixtures. The mass filter is set to selectively inject ions of a particular m/z or, in scanning mode, to sequentially inject ions into the QITMS for subsequent manipulation and detection. Performance of the instrument is demonstrated using a mixture of ions created by electron impact ionization of perfluorotributylamine (FC-43) and peptide ions generated by pulsed Cs+ bombardment. Resulting data are compared to those obtained by utilizing only the ion trap. Molecular weight, fragmentation, and high-resolution analyses for the sequentially injected mass-filtered peptides show improved performance over similar measurements employing only the ion trap mass spectrometer. Performance is optimized when ions are not rf-isolated in the QITMS. Using the hybrid, a resolution of 33 200 is achieved for angiotensin I. Dramatic reduction of ...
Children Exposed to Cocaine: Characteristics and Implications for Research and Intervention.

The 1990 President's National Drug Controi Strategy Report estimated that 100,000 babies who have been prenatally exposed to cocaine are born each year. Medical research has established risks for b...
Is c-kit (CD117) immunolocalization in cell block preparations useful in the differentiation of adenoid cystic carcinoma from pleomorphic adenoma?

Recent studies in the surgical pathology literature have revealed that overexpression of the tyrosine kinase receptor protein c-kit (CD117) occurs in adenoid cystic carcinoma, suggesting that c-kit may be useful as an ancillary marker for this tumor. This marker would be particularly useful in small biopsies and in cell block preparations of fine-needle aspiration biopsy (FNAB) material, in which differentiation between adenoid cystic carcinoma and pleomorphic adenoma can be challenging and carries important therapeutic implications. We evaluated the role of c-kit antigen expression in cell block material obtained during FNAB in distinguishing between adenoid cystic carcinoma and pleomorphic adenoma. Formalin-fixed, paraffin-embedded cell block sections of pleomorphic adenoma specimens from the parotid (n 13) and submandibular glands (n 2), as well as adenoid cystic carcinoma specimens from the palate (n 3), maxilla (n 2), buccal mucosa (n 2), tongue (n 1), parotid (n 1), and ethmoid sinus (n 1), were selected from the archival pathology files of the State University of New York–Upstate Medical University (Syracuse, NY). All patients had subsequently undergone surgical excision, and the corresponding tissue analysis confirmed the FNAB diagnosis in all cases. Immunohistochemical studies were performed on formalin-fixed, paraffinembedded tissue sections measuring 4 m in thickness using a modified avidin-biotin-peroxidase complex detection method. Two antibodies were used to detect c-kit expression: H300, a polyclonal antibody against the amino terminus of human c-kit (1:65 dilution; Santa Cruz Biotechnology, Santa Cruz, CA), and A4502, a polyclonal 207 CANCER CYTOPATHOLOGY
Effects of food deprivation on cocaine base smoking in rhesus monkeys.

Studies have shown that both food deprivation and response cost have important influences on the magnitude of self-administration of a wide variety of psychoactive drugs. In an attempt to extend these findings to the smoked route of drug self-administration, the effects of food allotment and fixed-ratio (FR) value were evaluated in four male rhesus monkeys trained to smoke cocaine base. In the first phase of the experiment, monkeys were trained to self-administer smoked cocaine base under a chained progressive-ratio (PR), fixed-ratio (FR) schedule during daily experimental sessions. Monkeys were required to make 20 lever-press responses and then five inhalations on a smoking spout to obtain the first smoke delivery. The lever ratio then increased to 60, 140, 300, 620, 1260, 2540, and 4940 for each successive smoke delivery. The initial lever ratio value was reset to 20 at the beginning of each daily session. The body weights of three monkeys were determined under free-feeding conditions. Monkeys were then restricted to 100 g food and, when body weights had stabilized, the daily food allotment was increased to 150 g, approximately 210 g, or greater than 400 g (satiation). As the daily food allotment and body weight increased, the mean number of smoke deliveries decreased in two of three monkeys. In the second phase of the experiment, three monkeys were maintained under either food-satiated or food-restricted conditions. Body weights were maintained at approximately 90% of their free-feeding weights under food-restricted conditions. The cost of the drug (lever FR value) was constant within each experimental session, but was increased after 3 consecutive days of stable responding. Fixed-ratio values were increased from 128 to 256, 512, 1024, and 2048. Monkeys were required to complete the lever FR value and then to make five inhalations on the smoking spout to gain access to 1.0 mg/kg per delivery cocaine base. The mean number of smoke deliveries increased at FR 256, 512, and 1024 when monkeys were food-restricted as opposed to food-satiated. Correspondingly, the mean number of responses increased under food-restricted conditions. Responding continued to increase over a wider range of FR values, and the peak number of responses was higher under food-restricted, as opposed to food-satiated conditions. These results, using the smoking route of administration, are consistent with the hypothesis that food deprivation increases the self-administration of reinforcing drugs.