cssi/SciSciGPT-SciSciNet huggingface dataset:
EDB: A Case Study in Communicating Risk

This is a report on the Environmental Protection Agency's (EPA's) efforts to communicate with the public about the risks of ethylene dibromide (EDB), what the agency said it was doing about these risks and what information the public actually received through television and newspapers. Although special in many ways, the EDB case illustrates the problems that regulatory agencies have when they must take regulatory action and assure the public that the risks in question are being dealt with adequately. It also illustrates issues that the press faces. Above all, it illustrates the barriers to communication presented by the different perspectives of regulatory agencies and individuals and the types of information they each are most interested in.
Sub-micron scale mechanical properties of polypropylene fibers exposed to ultraviolet and thermal degradation

Nanoindentation studies using atomic force microscopy (AFM) was conducted to investigate the effect of accelerated ultra violet (UV) and thermal degradation on mechanical properties of Polypropylene textile fibers. The Polypropylene fibers with initial stabilizers were exposed to UV degradation using Q-UV Panel Weatherometer. The effect of degradation on gradation of Young’s modulus values across fiber cross-section was investigated by doing progressive nanoindentation from the surface to the center of the fiber. It was identified that UV degradation initially increases the Young’s modulus values from center to surface of the fibers till 120 hours of exposure and the values show decreasing trend at 144 hours of exposure. The Youngs modulus values at 144 hours exposure are less than those of unexposed fibers. To investigate thermal degradation effect on Polypropylene fibers, the fibers were exposed to 125oC as a function of number of weeks in increments of one week for four weeks. Results indicate that the thermal exposure did not have much impact on variation of Young’s modulus values for the first three weeks and showed increase in Young’s modulus values at the surface when they are exposed to four weeks. The increase in Young’s modulus values of Polypropylene fibers exposed to UV will be correlated with oxidation chemistry and micro-structural changes using Wide Angle X-ray spectroscopy and infra red spectroscopy techniques.
Measurements of temperature-dependent argon-broadened half-widths of H2O transitions in the 7117 cm−1 region

Abstract A distributed-feedback InGaAsP diode laser has been used to perform spectrally resolved measurements of H2O transitions near 7117cm−1. Line shape analyses of the recorded absorption spectra yielded the temperature-dependent Ar-broadened half-widths. Room-temperature (296K) half-widths for four transitions were determined with an uncertainty of +7%/−5%. Temperature exponents for three of these transitions were determined over the range of 296–473 K with an uncertainty of ±7%.
Changes in cellular levels of inositol polyphosphates during apoptosis

Accumulations of higher inositol polyphosphates, diphosphoinositol polyphosphates or pyrophosphates, have been implicated to mediate cellular apoptosis. Whether cellular levels of lower inositol phosphates (lower than inositol hexakisphosphates) change during apoptosis is not known, although these inositol phosphates are known to play crucial roles in a number of cellular signaling processes including calcium mobilization. Therefore, in this study, we have examined changes in cellular levels of inositol phosphates following metabolic labeling of these compounds by [3H]myo-inositol and induction of apoptosis. The levels of inositol mono- and bis-phosphates were increased, whereas the levels of inositol tris- and tetrakis-phosphates decreased significantly with an increasing rate of apoptosis induced by etoposide in a dose-dependent manner. NaF treatment, which increased the rate of apoptosis in a time- and dose-dependent manner, also increased the levels of inositol mono- and bis-phosphates and drastically reduced the levels of inositol tris- and tetrakis-phosphates. Prior treatment with antimycin A, a strategy used to reverse the NaF-induced accumulations of higher InsPs, partially reduced the effects of NaF on apoptosis as well as the levels of lower InsPs. Taken together, our results suggest that cellular levels of lower InsPs are altered during apoptosis.
Multiple-Layer, Direct-Compression, Controlled-Release System: In Vitro and In Vivo Evaluation

A new approach to achieve controlled drug delivery Is demonstrated for a triple-layer tablet, which simultaneously combines the principles of diffusion and dissolution. Heckel’s equation was used to characterize the compression behavior of formulation components. A balanced proportion of each component and a model drug (theophylline) were selected to avoid lamination after ejection and ensure coherent compaction, in vitro release profiles over a period of 10 h In different dissolution media and hydrodynamic conditions were similar and resulted in an n value of 0.786, signifying anomalous release kinetics. The n value is calculated from a curve fit to the empirical equation: Mt/M∞= Ktn, where Mt and M∞ denote the amount of drug released at time t and at infinite time, respectively, K denotes the proportionality constant, and n characterizes the type of release mechanism operative during the dissolution process. In vivo study in human subjects after administration of the experimental triple-layer system exhibited a steady rise in plasma concentration up to 7 h. The actual amount of drug absorbed by the body was calculated by the Wagner-Nelson technique, and a linear relationship was observed between the percentage absorbed In vivo and the percentage dissolved in vitro. The proposed triple-layer model appears to provide good correlation between In vitro and In vivo results with maximum flexibility with respect of dose, duration range, and ease of production.
The mechanical theory of fluid interfaces and Maxwell's rule

Abstract By operating within a recently developed mechanical theory of fluid interfaces we find that Maxwell's equal area rule fails to hold unless certain molecular conditions are satisfied. In view of these conditions various statistical models for fluid interfaces which have previously been proposed need to be restricted if they are to be compatible with the equal area rule. We show that in both concept and fact the mechanical theory is more general than previous interfacial theories which as a rule assume the existence of thermodynamic functions and the validity of thermodynamic relations within the spinodal set. In particular, we list necessary and sufficient conditions for the reduction of the mechanical theory to the modified and original van der Waals theories of fluid interfaces. These conditions are also molecular in nature, the reduction being accomplished without the use of thermodynamic reasoning within the spinodal region. Finally, we consider three-dimensional interfaces and note that when the conditions for Maxwell's rule and van der Waals' theory are not satisfied, then the interfaces are generally planar, cylindrical, or spherical at equilibrium.
Cloning of a mouse homolog of CD94 extends the family of C-type lectins on murine natural killer cells.

Two families of major histocompatibility complex (MHC) class I-specific receptors are found on natural killer (NK) cells: immunoglobulin-like receptors and C-type lectin receptors. In mice, the latter category is represented by the Ly49 family of receptors, whereas in humans, NK cells express the distantly related CD94, which forms MHC class I-specific heterodimers with NKG2 family members. Humans also express the MHC class I-specific p50/p58/p70 family of immunoglobulin-like receptors, but these have not been identified in mice. Hence, there is no known instance of an MHC class I-specific receptor that is expressed by both human and murine NK cells. Here we report the cloning of CD94 from the CB.17 and C57BL/6 strains of mice. Mouse CD94 is 54 % identical and 66 % similar to human CD94, and is also a member of the C-type lectin superfamily. Mouse CD94 is expressed efficiently on the cell surface of cells transiently transfected with the corresponding cDNA, but surface CD94 was unable to mediate detectable binding to MHC class I-expressing ConA blasts. Notably, mouse CD94, like human CD94, has a very short cytoplasmic tail, suggesting the existence of partner chains that may play a role in ligand binding and signaling. Like many other C-type lectins expressed by NK cells, mouse CD94 maps to the NK complex on distal chromosome 6, synteneic to human CD94. We also demonstrate that mouse CD94 is highly expressed specifically by mouse NK cells, raising the possibility that mice, like humans, express multiple families of MHC class I-specific receptors on their NK cells. Murine homologs of human NKG2 family members have not yet been identified, but we report here the existence of a murine NKG2D-like sequence that also maps to the murine NK complex near CD94 and Ly49 family members.
EUV spectra of Mo XIV to Mo XXIX

Abstract Observations of the EUV spectra of Mo XIV to Mo XXIX have been made in the wavelength region from 5 to 50 nm by foil excitation of 22 to 200 MeV Mo ion beams. The results are compared with spectra observed in tokamak plasmas and light sources and with theoretical predictions.
A stochastic analysis of steady and transient heat conduction in random media using a homogenization approach

Abstract We present a new stochastic analysis for steady and transient one-dimensional heat conduction problem based on the homogenization approach. Thermal conductivity is assumed to be a random field K consisting of random variables of a total number N. Both steady and transient solutions T are expressed in terms of the homogenized solution T ∼ and its spatial derivatives T ( x , t ) = T ∼ + ∑ n = 1 ∞ L n ( x ) ∂ n T ∼ / ∂ x n , where homogenized solution T ∼ is obtained by solving the homogenized equation with effective thermal conductivity. Both mean and variance of stochastic solutions can be obtained analytically for K field consisting of independent identically distributed (i.i.d) random variables. The mean and variance of T are shown to be dependent only on the mean and variance of these i.i.d variables, not the particular form of probability distribution function of i.i.d variables. Variance of temperature field T can be separated into two contributions: the ensemble contribution (through the homogenized temperature T ∼ ); and the configurational contribution (through the random variable L n ( x ) ). The configurational contribution is shown to be proportional to the local gradient of T ∼ . Large uncertainty of T field was found at locations with large gradient of T ∼ due to the significant configurational contributions at these locations. Numerical simulations were implemented based on a direct Monte Carlo method and good agreement is obtained between numerical Monte Carlo results and the proposed stochastic analysis.
Predictors of ischemic stroke after hip operation: A population‐based study

BACKGROUND: Hip operation (total hip arthroplasty [THA] or fracture repair) is the most common noncardiac surgical procedure performed in patients age 65 years and older. OBJECTIVE: To determine the predictors of ischemic stroke in patients who have undergone hip operation. DESIGN: Population-based historical cohort study, in which postoperative ischemic strokes were identified from medical record review for stroke diagnostic codes and brain imaging results and were confirmed by physician review. SETTING: Tertiary care center in Olmsted County, Minnesota. PATIENTS: Residents of Olmsted County who underwent hip surgical procedure. MEASUREMENTS: Incidence of ischemic stroke within 1 year of hip operation. RESULTS: In total, 1606 patients underwent 1886 hip procedures from 1988 through 2002 and were observed for ischemic stroke for 1 year after their procedure. Sixty-seven ischemic strokes were identified. The rate of stroke at 1 year after hip operation was 3.9%. In univariate analysis, history of atrial fibrillation (hazard ratio [HR], 2.16; P = 0.005), hip fracture repair vs. total hip arthroplasty (HR, 3.80; P < 0.001), age 75 years or older (HR, 2.20; P = 0.02), aspirin use (HR, 1.8; P = 0.01), and history of previous stroke (HR, 4.18; P < 0.001) were significantly associated with increased risk of stroke. In multivariable analysis, history of stroke (HR, 3.27; P < 0.001) and hip fracture repair (HR, 2.74; P = 0.004) were strong predictors of postoperative stroke. CONCLUSIONS: This population-based historical cohort of patients with hip operation had a 3.9% cumulative probability of ischemic stroke over the first postoperative year. Hip fracture repair and history of stroke were the strongest predictors of this complication. Journal of Hospital Medicine 2009;4:298–303. © 2009 Society of Hospital Medicine.
Doppler-free optical multiplex spectroscopy with stochastic excitation

By using the concept of stochastic excitation, a multichannel optical spectrometer was developed with an inherent spectral resolution in the kilohertz domain. Stochastic optical fields are obtained by phase modulating a frequency-stabilized Ar+ laser with a pseudorandom binary sequence. This sequence is characterized by an autocorrelation time of 5 nsec, with a resulting excitation bandwidth of approximately 200 MHz. A signal related to an optical free-induction decay is obtained after cross correlating the response of the system with the time-delayed stochastic excitation sequence. The performance of the spectrometer was demonstrated by observing Doppler-free transitions of molecular iodine.
The role of atomistic simulations in probing the small-scale aspects of fracture—a case study on a single-walled carbon nanotube

Abstract This paper reviews atomistic simulation (AS) of fracture of solids along with recent advances reported in the literature. While classical fracture mechanics is based on continuum assumptions, AS can provide a first-principles based description of fracture that accounts for the discrete nature of matter. The idea of atomistic simulation was first applied to fracture during the early 1970s; brittle fracture was studied first using simple potential models and equilibrium conditions. Advances in materials science and computational power have led to significant progress in AS of fracture. Since the early 1990s, complex phenomena such as ductile fracture, fracture of non-homogeneous materials, fracture interaction with other physical and chemical effects have increasingly been investigated by atomistic simulation. This paper discusses achievements and shortcomings in regard to fracture criteria, potential models, initial and boundary conditions, temperature control and multi-scale simulation. An atomistic simulation of the displacement-controlled fracture process of a single-walled carbon nanotube (SWNT) with a pre-existing Stone–Wales defect is given as an example highlighting the essential steps of the methodology. Elastic modulus, ultimate strength and ultimate strain of the tube are determined from the simulation results (both with the defect and in the defect-free case) and the dependence of these parameters on the loading rate is investigated. Time histories of potential energy, temperature, axial force and bond angle are described, and a series of snapshots detailing the progress of the fracture process is provided.
Graviresponsiveness of surgically altered primary roots of Zea mays.

We examined the gravitropic responses of surgically altered primary roots of Zea mays to determine the route by which gravitropic inhibitors move from the root tip to the elongating zone. Horizontally oriented roots, from which a 1-mm-wide girdle of epidermis plus 2-10 layers of cortex were removed from the apex of the elongating zone, curve downward. However, curvature occurred only apical to the girdle. Filling the girdle with mucilage-like material transmits curvature beyond the girdle. Vertically oriented roots with a half-girdle' (i.e. the epidermis and 2-10 layers of the cortex removed from half of the circumference of the apex of the elongating zone) curve away from the girdle. Inserting the half-girdle at the base of the elongating zone induces curvature towards the girdle. Filling the half-circumference girdles with mucilage-like material reduced curvature significantly. Stripping the epidermis and outer 2-5 layers of cortex from the terminal 1.5 cm of one side of a primary root induces curvature towards the cut, irrespective of the root's orientation to gravity. This effect is not due to desiccation since treated roots submerged in water also curved towards their cut surface. Coating a root's cut surface with a mucilage-like substance minimizes curvature. These results suggest that the outer cell-layers of the root, especially the epidermis, play an important role in root gravicurvature, and the gravitropic signals emanating from the root tip can move apoplastically through mucilage.
Mate Choice by Lekking Males: Evidence from the Mediterranean Fruit Fly From Field Cage Trials (Diptera: Tephritidae)

ABSTRACT The Mediterranean fruit fly (medfly), Ceratitis capitata (Wiedemann), exhibits a lek mating system characterized by intense female choice apparently based on male courtship performance. However, recent observations showed that receptive females are aggressive toward one another and compete for access to displaying males, suggesting that the traditional view that sexual competition in the medfly is restricted exclusively to males may not be accurate. The current study further examines the accepted view of the medfly mating system by investigating the possibility that males discriminate among potential mates on the basis of female age. In field cage trials, we scored matings for males presented with virgin females of different ages. Young females were mated more frequently than old females, and additional tests revealed that this pattern did not reflect age-dependent variation among virgin females in mating propensity or response to male signaling. Although the experimental environment was artifici...
Crystal structure of the signaling helix coiled-coil domain of the β1 subunit of the soluble guanylyl cyclase

The soluble guanylyl cyclase (sGC) is a heterodimeric enzyme that, upon activation by nitric oxide, stimulates the production of the second messenger cGMP. Each sGC subunit harbor four domains three of which are used for heterodimerization: H-NOXA/H-NOBA domain, coiled-coil domain (CC), and catalytic guanylyl cyclase domain. The CC domain has previously been postulated to be part of a larger CC family termed the signaling helix (S-helix) family. Homodimers of sGC have also been observed but are not functionally active yet are likely transient awaiting their intended heterodimeric partner. To investigate the structure of the CC S-helix region, we crystallized and determined the structure of the CC domain of the sGCβ1 subunit comprising residues 348-409. The crystal structure was refined to 2.15 A resolution. The CC structure of sGCβ1 revealed a tetrameric arrangement comprised of a dimer of CC dimers. Each monomer is comprised of a long a-helix, a turn near residue P399, and a short second a-helix. The CC structure also offers insights as to how sGC homodimers are not as stable as (functionally) active heterodimers via a possible role for inter-helix salt-bridge formation. The structure also yielded insights into the residues involved in dimerization. In addition, the CC region is also known to harbor a number of congenital and man-made mutations in both membrane and soluble guanylyl cyclases and those function-affecting mutations have been mapped onto the CC structure. This mutant analysis indicated an importance for not only certain dimerization residue positions, but also an important role for other faces of the CC dimer which might perhaps interact with adjacent domains. Our results also extend beyond guanylyl cyclases as the CC structure is, to our knowledge, the first S-helix structure and serves as a model for all S-helix containing family members.
Azathioprine-Induced Fever in Sarcoidosis

Objective:To report a case of drug-induced fever associated with azathioprine treatment in a patient with sarcoidosis.Case Summary:A 52-year-old man with pulmonary sarcoidosis presented to the emer...
The boundaries of strategic corporate social responsibility

Reviews the development of the corporate social responsibility (CSR) concept and its four components: economic, legal, ethical and altruistic duties. Discusses different perspectives on the proper role of business in society, from profit making to community service provider. Suggests that much of the confusion and controversy over CSR stem from a failure to distinguish among ethical, altruistic and strategic forms of CSR. On the basis of a thorough examination of the arguments for and against altruistic CSR, concurs with Milton Friedman that altruistic CSR is not a legitimate role of business. Proposes that ethical CSR, grounded in the concept of ethical duties and responsibilities, is mandatory. Concludes that strategic CSR is good for business and society. Advises that marketing take a lead role in strategic CSR activities. Notes difficulties in CSR practice and offers suggestions for marketers in planning for strategic CSR and for academic researchers in further clarifying the boundaries of strategic CSR.
Dealing with the family: CD147 interactions with cyclophilins

CD147 is a widely expressed plasma membrane protein that has been implicated in a variety of physiological and pathological activities. It is best known for its ability to function as extracellular matrix metalloproteinase inducer (hence the other name for this protein, EMMPRIN), but has also been shown to regulate lymphocyte responsiveness, monocarboxylate transporter expression and spermatogenesis. These functions reflect multiple interacting partners of CD147. Recently, interaction of CD147 with proteins of the cyclophilin family has been demonstrated and activity of CD147 as a signalling receptor to extracellular cyclophilins A and B has been shown. Given that extracellular cyclophilins are potent chemotactic agents for various immune cells, further studies of the role of cyclophilin-CD147 interaction in inflammation followed. They demonstrated that agents targeting CD147 or cyclophilin had a significant anti-inflammatory effect in animal models of acute or chronic lung diseases and rheumatoid arthritis. Here, we review the current knowledge about interactions between CD147 and cyclophilins.
Venous Obstruction Due to a Distended Urinary Bladder

Bladder distention is an infrequently reported cause of venous obstruction that may be confused clinically with deep venous thrombosis or congestive heart failure. Urinary symptoms may be minimal or absent. Herein we describe a 73-year-old man with unilateral lower extremity edema caused by a distended urinary bladder. In addition, we review the clinical manifestations of 15 previously reported cases of venous obstruction due to urinary retention. Of the 15 patients, all but 1 had painless bilateral lower extremity edema. In most cases, the cause of bladder distention was benign prostatic enlargement.
The role of mismatched nucleotides in activating the hMSH2-hMSH6 molecular switch.

Abstract We have previously shown that hMSH2-hMSH6 contains an intrinsic ATPase which is activated by mismatch-provoked ADP→ATP exchange that coordinately induces the formation of a sliding clamp capable of hydrolysis-independent diffusion along the DNA backbone (1, 2). These studies suggested that mismatch repair could be propagated by a signaling event transduced via diffusion of ATP-bound hMSH2-hMSH6 molecular switches to the DNA repair machinery. The Molecular Switch model (Fishel, R. (1998) Genes Dev. 12, 2096–2101) is considerably different than the Hydrolysis-Driven Translocation model (Blackwell, L. J., Martik, D., Bjornson, K. P., Bjornson, E. S., and Modrich, P. (1998) J. Biol. Chem. 273, 32055–32062) and makes additional testable predictions beyond the demonstration of hydrolysis-independent diffusion (Gradia, S., Subramanian, D., Wilson, T., Acharya, S., Makhov, A., Griffith, J., and Fishel, R. (1999) Mol. Cell3, 255–261): (i) individual mismatch-provoked ADP→ATP exchange should be unique and rate-limiting, and (ii) thek cat·DNA for the DNA-stimulated ATPase activity should decrease with increasing chain length. Here we have examined hMSH2-hMSH6 affinity and ATPase stimulatory activity for several DNA substrates containing mispaired nucleotides as well as the chain length dependence of a defined mismatch under physiological conditions. We find that the results are most consistent with the predictions of the Molecular Switch model.
Differentiating Branch Duct and Mixed IPMN in Endoscopically Collected Pancreatic Cyst Fluid via Cytokine Analysis

Background. Differentiating branch duct from mixed intraductal papillary mucinous neoplasm (BD-IPMN) is problematic, but clinically important as mixed IPMNs are managed surgically, while some BD-IPMN may be followed. Inflammatory mediator proteins (IMPs) have been implicated in acute and chronic inflammatory and malignant pancreatic diseases. Aim. To compare IMP profile of pancreatic cyst fluid collected endoscopically from BD-IPMN and mixed IPMN. Methods. Pancreatic cyst fluid from ten patients (5 BD-IPMN and 5 mixed IPMN) was collected by endoscopic ultrasound-guided fine needle aspiration or endoscopic retrograde cholangiopancreatography. Concentrations of 89 IMPs in these samples were determined using a multiplexed bead-based microarray protein assay and compared between BD-IPMN and mixed IPMN. Results. Eighty-six of 89 IMPs were detected in at least one of the 10 samples. Fourteen IMPs were detected only in mixed IPMN, while none were only in BD-IPMN. Of these, TGF-β1 was most prevalent, present in 3 of 5 mixed IPMNs. Seventy-two IMPs were detected in both BD-IPMN and mixed IPMNs. Of these, only G-CSF (P < 0.05) was present in higher concentrations in mixed IPMNs. Conclusion. TGF-β1 and G-CSF detected in endoscopically collected pancreatic cyst fluid are potential diagnostic biomarkers capable of distinguishing mixed IPMN from BD-IPMN.
PULMONARY EDEMA IN INFLUENZAL PNEUMONIA OF THE MOUSE AND THE RELATION OF FLUID IN THE LUNG TO THE INCEPTION OF PNEUMOCOCCAL PNEUMONIA

Pulmonary edema is a component of the fully developed influenza viral lesion in the mouse. Mice with experimental pulmonary fluid have an increased susceptibility to inhaled pneumococci and under these circumstances the organisms grow in the lung and produce the lesion of bacterial pneumonia. The presence of pulmonary edema in the lesion due to the influenza virus in the lung of the mouse appears to account adequately for the previous observation that inhaled pneumococci grow in the influenza viral lesion. Mice dying of pneumococcal septicemia after inhaling fine droplets containing this organism do not have pneumonia. The delay in migration of polymorphonuclear leucocytes into the lung after injection of pneumococci suspended in serum is an important factor in susceptibility to infection since it allows ample time for pneumococci to grow in the pulmonary fluid. The slow phagocytic action of pulmonary macrophages likewise permits growth of pneumococci. Conditions in human beings that are known to be complicated by pulmonary edema are also known to be associated with increased susceptibility to secondary bacterial pneumonia.
Two randomized trials provide no consistent evidence for nonmusical cognitive benefits of brief preschool music enrichment.

Young children regularly engage in musical activities, but the effects of early music education on children’s cognitive development are unknown. While some studies have found associations between musical training in childhood and later nonmusical cognitive outcomes, few randomized controlled trials (RCTs) have been employed to assess causal effects of music lessons on child cognition and no clear pattern of results has emerged. We conducted two RCTs with preschool children investigating the cognitive effects of a brief series of music classes, as compared to a similar but non-musical form of arts instruction (visual arts classes, Experiment 1) or to a no-treatment control (Experiment 2). Consistent with typical preschool arts enrichment programs, parents attended classes with their children, participating in a variety of developmentally appropriate arts activities. After six weeks of class, we assessed children’s skills in four distinct cognitive areas in which older arts-trained students have been reported to excel: spatial-navigational reasoning, visual form analysis, numerical discrimination, and receptive vocabulary. We initially found that children from the music class showed greater spatial-navigational ability than did children from the visual arts class, while children from the visual arts class showed greater visual form analysis ability than children from the music class (Experiment 1). However, a partial replication attempt comparing music training to a no-treatment control failed to confirm these findings (Experiment 2), and the combined results of the two experiments were negative: overall, children provided with music classes performed no better than those with visual arts or no classes on any assessment. Our findings underscore the need for replication in RCTs, and suggest caution in interpreting the positive findings from past studies of cognitive effects of music instruction.
Mandatory Screening of Pregnant Women for the Human Immunodeficiency Virus

In this AIDS Commentary, Dr. Catherine Wilfert addresses the issue of vertical transmission of the human immunodeficiency virus type 1 (HIV-1). She reviews the results of the recently completed trial conducted by the AIDS Clinical Trials Group that evaluated the effectiveness of administering zidovudine to pregnant women in reducing the incidence of vertical transmission. In view of the success of this trial, Dr. Wilfert addresses the problem of the efficacy of voluntary counseling and testing of pregnant women. Identification and treatment of HIV-1 infected women could potentially reduce the incidence of pediatric HIV-1 infection and increase the number of women receiving appropriate therapy. She makes the point that legislative mandates have been necessary to produce rates of childhood immunization that are effective in reducing the occurrence of vaccine-preventable diseases. This suggests that such mandates are an option to consider in the effort to control vertical transmission of HIV-1 infection. Her cost-benefit analysis indicates that universal screening of pregnant women for HIV infection would result in enormous overall savings for the health care system. Obviously, making the testing of pregnant women mandatory raises a number of difficult issues and is controversial. Dr. Wilfert has provided a service by raising this issue; further discussion is needed.
Constructing facial composites with the mac-a-mug pro system

Abstract Sixty-two witnesses observed a target person and two days later either verbally described or constructed a facial composite of the target using the Mac-A-Mug Pro facial composite system. The composite production was preceded by either a guided memory or a standard police interview. The resulting composites were of low quality (not at all similar to a photograph of the target) and were of no value in selecting the target from a group of similar-looking people. It was suggested that the Mac-A-Mug Pro system is not useful for realistic witness settings, in which witnesses must construct the composites from memory. Suggestions are provided for modifying facial composite systems to make them more compatible with the psychological processes mediating face recall.
An integrated approach for generic object detection using kernel PCA and boosting

In this paper, we present a novel framework for generic object class detection by integrating Kernel PCA with AdaBoost. The classifier obtained in this way is invariant to changes in appearance, illumination conditions and surrounding clutter. A nonlinear shape subspace is learned for positive and negative object classes using kernel PCA. Features are derived by projecting example images onto the learned sub-spaces. Base learners are modeled using Bayes classifier. AdaBoost is then employed to discover the features that are most relevant for the object detection task at hand. Proposed method has been successfully tested on wide range of object classes (cars, airplanes, pedestrians, motorcycles etc) using standard data sets and has shown good performance. Using a small training set, the classifier learned in this way was able to generalize the intra-class variation while still maintaining high detection rate. In most object categories, we achieved detection rates of above 95% with minimal false alarm rates. We demonstrate the comparative performance of our method against current state of the art approaches.
Displacement damage in silicon due to secondary neutrons, pions, deuterons, and alphas from proton interactions with materials

The enhancement of displacement damage energy deposition due to secondary neutrons, pions, deuterons, and alphas resulting from high-energy (100-1000 MeV) proton interactions with aluminum and tungsten shielding are examined in this paper. The results obtained using a comprehensive Monte Carlo charged particle transport code, MCNPX Version 2.1.5, indicated that the dominant secondary particle is neutrons. The additional contribution to the displacement damage energy produced by secondary pions, deuterons, and alphas turned out to be less than 5%.
FUEL SULFUR EFFECTS ON THE PERFORMANCE OF AUTOMOTIVE THREE-WAY CATALYSTS DURING VEHICLE EMISSIONS TESTS

Vehicle exhaust emissions tests, using the Federal Test Procedure, were conducted to deter mine the effect of gasoline sulfur content on the performance of three-way catalysts. The test fuels had sulfur concentrations of 0.01, 0.03, and 0.09 per cent. An increase in the fuel sulfur content from 0.01 to 0.09 percent reduced the conversion of hydro carbons, carbon monoxide, and oxides of nitrogen, resulting in higher tailpipe emissions. The effects were generally small, but statistically significant. The lower conversion was due to poisoning of the catalyst by sulfur species in the exhaust. The poison ing was reversible.
Mechanism of FGF receptor dimerization and activation

Fibroblast growth factors (fgfs) are widely believed to activate their receptors by mediating receptor dimerization. Here we show, however, that the FGF receptors form dimers in the absence of ligand, and that these unliganded dimers are phosphorylated. We further show that ligand binding triggers structural changes in the FGFR dimers, which increase FGFR phosphorylation. The observed effects due to the ligands fgf1 and fgf2 are very different. The fgf2-bound dimer structure ensures the smallest separation between the transmembrane (TM) domains and the highest possible phosphorylation, a conclusion that is supported by a strong correlation between TM helix separation in the dimer and kinase phosphorylation. The pathogenic A391E mutation in FGFR3 TM domain emulates the action of fgf2, trapping the FGFR3 dimer in its most active state. This study establishes the existence of multiple active ligand-bound states, and uncovers a novel molecular mechanism through which FGFR-linked pathologies can arise.
A polypeptide from male accessory glands which triggers maturation of tick spermatozoa

The maturation of tick (Acari: Ixodoidea) spermatozoa, after their transfer to the female, is induced by secretions of the male accessory gland which are added to the prospermia during ejaculation. Analysis of the secretions from male Ornithodoros moubata (Argasidae) and Dermacentor variabilis (Ixodidae) indicates that the factor responsible for inducing maturation is a polypeptide with a molecular weight of about 12,500. Although the polypeptides from the two species are similar in most respects, each will not activate the prospermia of the other species. The mode of action of the factor is hormone-like, inasmuch as a few minutes of exposure of the sperm to the factor are sufficient to trigger the entire maturation sequence, which takes 12–24 h in vitro.
Approximation of Agent Dynamics Using Reinforcement Learning

Reinforcement Learning for control of dynamical systems is popular due to the ability to learn control policies without requiring a model of the system being controlled. It can be dicult to learn ideal control policies because it is common to abstract out or ignore completely the dynamics of the agents in the system. In this paper, Reinforcement Learning-based algorithms are developed for learning agents’ time dependent dynamics while also learning to control them. Three algorithms are introduced. Sampled-Data Q-learning is an algorithm that learns the optimal sample time for controlling an agent without a prior model. First-Order Dynamics Learning is an algorithm that determines the proper time constants for agents known to have rst-order dynamics, while Second-Order Dynamics Learning is an algorithm for learning natural frequencies and damping ratios of second-order systems. The algorithms are demonstrated with numerical simulation. Results presented in this paper show that the algorithms are able to determine information about the system dynamics without resorting to traditional system identication.
A Study on the Radiance Distribution in the Canopy Affected by Non-Lambert Characteristics of Leaf Based on RGM

As one of the computer simulation models,the Radiosity-Graphics combined Model(RGM) has many advantages in calculating the bidirectional reflectance factor(BRF).Because it takes advantage of radiosity theory and computer graphics technique,the model can contain much more detailed and complex structures of vegetation canopy and take reflection,transmission and multiple scattering into account,which is useful to understand the interaction between the light and the canopy.A hypothesis of Lambertian is made in the general radiosity theory,namely,all surfaces of components(i.e.,leaves,stem and background) in the scene are Lambert reflection/transmission.In fact,studies of the properties of leaves have shown that the bidirectional reflectance distribution functions(BRDF) of most leaves' surfaces are not isotropic.In order to apply RGM to calculate the radiance distribution caused by the non-Lambert(specular) component,a semi-experimental Phong model is used to evaluate the specular radiosity from leaves' surfaces.This method is applied to the maize canopy,and the results are analyzed.As an interesting experiment,this extended RGM,which includes diffuse and specular component at the same time,not only keeps the advantages of the general radiosity theory,but also eliminates the hypothesis of Lambertian in vegetation scene.
Novel Indicators of Anthropogenic Influence on Marine and Coastal Ecosystems

Human populations are concentrated along coastal regions worldwide, placing a disproportionate stress on coastal marine ecosystems. Ironically, biogenic habitats may be adversely affected by human activities though they serve to attenuate the impacts of global change on coastal cities. Surprisingly, simple, coastwide indicators of anthropogenic influences in relation to the spatial distribution of biogenic habitats are relatively underdeveloped. In this paper, we introduce a spatially explicit index of coastal as well as upland riverine human population proximity, based on human population and river dynamics datasets on the West- and Gulf-Coasts of the US. We then examine the relationship between these indices and biogenic habitats (kelp and mangrove forests). Finally, we identify patterns of landscape-scale biodiversity with human populations, and explore occurrence of biogenic habitats within and outside of marine protected areas (MPAs). We found that biogenic habitats were negatively associated with human populations and that MPAs were generally placed away from people. Landscape-scale patterns of biodiversity did not differ within and outside kelp forests and MPAs on the West Coast, but had a negative association with mangroves and a positive association with MPAs on the Gulf Coast. This index can be used anywhere in the world, can project into the future using various human population growth forecasts, and can serve as an important method for conservation triage.
A Strategy for Dosing Vancomycin to Therapeutic Targets Using Only Trough Concentrations

Effective treatment of complicated methicillin-resistant Staphylococcus aureus (MRSA) infections with vancomycin requires a 24-h area under the concentration–time curve (AUC24) to minimum inhibitory concentration (MIC) ratio of at least 400. To ensure goal AUC24 has been reached requires either dosing to concentrations strongly associated with nephrotoxicity, measurement of patient-specific pharmacokinetics, or use of Bayesian statistics. In this study, we show a method of determining patient-specific pharmacokinetics and dosing to therapeutic AUC24 while minimizing potentially toxic concentrations, guided by only trough measurements. A Monte–Carlo simulation of 10,000 patients with complicated MRSA infections was prepared from two-compartment pharmacokinetic parameters using patient data extracted from the literature. The proposed method of determining patient-specific pharmacokinetics using consecutive trough concentrations was found to be more accurate than the conventional peak-trough method for peaks measured up to 4 h after infusion. Simulated human error in trough timing was found to reduce accuracy of the consecutive trough method, but an approach to resolve timing errors during a loading sequence or at steady-state using iteration is proposed. Both the simulated minimized concentration strategy and trough-based dosing to 15–20 mg/L had a high probability of achieving AUC24 at least 400 mg·h/L, but conventional trough-based dosing was associated with higher probability of potentially toxic 24-h doses and trough concentrations. The proposed strategy must be validated in real patients, with outcomes assessed before it is used in daily practice, but the theoretical benefits found in the simulation suggest this simple strategy should be considered with other AUC24-based approaches.
Prevention of Fatal Child Maltreatment: What Are We Doing That Is Working?

This chapter addresses the prevention of fatal child maltreatment. Most efforts in this arena have concerned the prevention of child abuse and neglect in general, because if one prevents this, then abuse or neglect-related deaths are also prevented. That said, there have been some efforts to educate parents or the general public about certain types of caregiving behaviors that might especially place a child at-risk for fatality, such as shaking a baby or leaving a child unattended in a vehicle. This chapter reviews the efficacy of these approaches and then discusses common child maltreatment-prevention programs—visiting home services and parenting education—and their application to fatal maltreatment.
Host nuclear genotype influences phenotype of a conditional mutualist symbiont

Arthropods commonly carry maternally inherited intracellular bacterial symbionts that may profoundly influence host biology and evolution. The intracellular symbiont Rickettsia sp. nr. bellii swept rapidly into populations of the sweetpotato whitefly Bemisia tabaci in the south-western USA. Previous laboratory experiments showed female-bias and fitness benefits were associated with Rickettsia infection, potentially explaining the high frequencies of infection observed in field populations, but the effects varied with whitefly genetic line. Here, we explored whether host extranuclear or nuclear genes influenced the variation in the Rickettsia–host phenotype in two genetic lines of the whitefly host, each with Rickettsia-infected and uninfected sublines. Introgression between the Rickettsia-infected subline of one genetic line and the Rickettsia-uninfected subline of the other was used to create two new sublines, each with the maternally inherited extranuclear genetic lineages of one line (Rickettsia, two other symbionts and the mitochondria) and the nuclear genotype of the other. Performance assays comparing the original and new lines showed that in addition to Rickettsia, the interaction of Rickettsia infection with host nuclear genotype influenced development time and the sex ratio of the progeny, whereas the extranuclear genotype did not. Host nuclear genotype, but not extranuclear genotype, also influenced the titre of Rickettsia. Our results support the hypothesis that differences in host nuclear genotype alone may explain considerable within-population variation in host–symbiont phenotype and may contribute to the observed variation in Rickettsia–whitefly interactions worldwide.
Adjustment and Developmental Patterns of African American Males: The Roles of Families, Communities, and Other Contexts

Despite the numerous challenges that most African American males confront, growing up in a society in which they and their families continue to be marginalized, many are able to survive and thrive. In this chapter, consideration is given to examining both struggles and victories confronting African Americans raising healthy sons. Drawing on Ecodevelopmental theory, and a relational development system model, we highlight the protective nature of families in buffering their sons from risk often associated with disparities confronting African American males, including academic outcomes and behavioral health, namely conduct/delinquent problems and early sexual initiation and substance/drug use. Further, the protective nature of person-context relations are examined to identify malleable targets that can be manipulated in preventive interventions aimed to reduce disparities in these multiple domains. Finally, our review raises an important question: Why is the study of African American male’s adjustment and development primarily based on their lived experiences in public spaces and institutions and void of their lives as members of families? The implications of this omission for theory building, research, and policy are discussed.
Stability of model predictive control with soft constraints

We derive stability conditions for model predictive control (MPC) with hard constraints on the inputs and "soft" constraints on the outputs for an infinitely long output horizon. We show that with state feedback MPC is globally asymptotically stabilizing if and only if all the eigenvalues of the open loop system are in the closed unit disk. With output feedback the eigenvalues must be strictly inside the unit circle. The online optimization problem defining MPC can be posed as a finite dimensional quadratic program even though the output constraints are specified over an infinite horizon. >