cssi/SciSciGPT-SciSciNet huggingface dataset:
Pulmonary Hypertension: “You Take My Breath Away”

Pulmonary hypertension is a disease process affecting the pulmonary vasculature and right heart with a high morbidity and mortality. Increases in pulmonary vasculature pressures cause both diastolic and systolic dysfunction of the right ventricle. The resulting preload-dependent output of the right ventricle makes patients sensitive to small fluid losses. The dilation of the right ventricle also causes increases in fluid volume to overstretch the right ventricle and reduce contractility. As a result, pulmonary hypertension patients live within a narrow margin of fluid balance. To aid right heart function many patients are continuously infused medication to reduce pulmonary resistance and right ventricle afterload. However, this also comes with complications, especially when there is an abrupt failure in the delivery of these medications. Overall, these are difficult patients to manage during acute episodes of decompensation due to their marginal cardiac function, hypersensitivity to changes in volume status, and limited usefulness of many exam findings or tests used to assess volume status.
The Impact of Intellectual Property and Regulatory Law on the Propagation of Medical Products to Various Countries

Has anyone ever wondered how people abroad have access to medical products developed in the United States? What processes did the medical products have to go through in order to be distributed in a foreign country and what affected the distribution? These are all questions that served as the basis for the Science, Technology and Society project of how regulatory and IP laws affect the propagation of medical products to various countries. This question was tackled through a comparative analysis of regulatory and IP laws in the US and South Africa, and an analysis of how their systems would impact the transfer of HIV/AIDS treatments and diagnostic tools from the US to South Africa. The STS framework of civic epistemology was selected to perform the comparative analysis. The approach of the paper was to: 1) define civic epistemology and the context in which it was being used for this project, 2) discuss IP law for the US and South Africa, 3) compare US and South Africa IP law through civic epistemology, 4) discuss regulatory law for the US and South Africa, 5) compare US and South Africa regulatory law through civic epistemology and, 6) use each country’s law to understand what affects the transfer of HIV/AIDS diagnostic tools and treatments from the US to South Africa. In the end it was discovered, that regulatory and IP systems can impact the availability of medical products distributed and marketed within a foreign country.
NAD(P)H: Quinone oxidoreductase (NQO1) and catalase expression in nonseminomatous germ cell tumors.

413Background: NAD(P)H:quinone oxidoreductase 1 (NQO1) is an enzyme which detoxifies quinones and reduces oxidative stress. NQO1 is expressed in multiple tumor types at levels up to 200-fold above ...
Incremental Analysis: For Retail Decision Making

All business students should have been exposed to the decision rule–proceed to the point where incremental benefits equal incremental costs. This rule is discussed in the context of decision making in'retailing. Varied incremental perspectives are offered. Diverse merchandising applications are derived from the following– how much extra profit do we make or less do we lose by selling one additional unit. Several decision tools are derived from the integration of incremental analysis into a retail decision framework. These include various measures of productivity, the principle of relative loss and the negotiation ratio. The shortcomings of incremental analysis are delineated.
Historical Fiction Picture Books

Historical fiction picture books represent a small subset of titles in the broader scope of the format. However, these books are important to both readers and educators. As books are used in educational settings it is critical to assess their effectiveness in helping teach children. This is especially true of historical fiction which generates its own unique challenges. To deeply assess historical fiction picture books we gathered and analyzed a sampling of 126 titles to assess trends in the genre. We found that there were multiple conflicts between the genre and format. There were many books in the sample that struggled with directing the content to a young audience, giving a accurate portrayal of race issues, and maintaining general authenticity and accuracy in the writing. There were also some notable examples of historical picture books that did not display these faults, showing that with the right content and approach, historical fiction picture books have the potential to be invaluable tools for teaching children.
Mental Health Burden After Injury: It's About More than Just Posttraumatic Stress Disorder.

Objective Assess the prevalence of anxiety, depression, and posttraumatic stress disorder (PTSD) after injury and their association with long-term functional outcomes. Background Mental health disorders (MHD) after injury have been associated with worse long-term outcomes. However, prior studies almost exclusively focused on PTSD. Methods Trauma patients with an injury severity score ≥9 treated at 3 Level-I trauma centers were contacted 6-12 months post-injury to screen for anxiety (generalized anxiety disorder-7), depression (patient health questionnaire-8), PTSD (8Q-PCL-5), pain, and functional outcomes (trauma quality of life instrument, and short-form health survey)). Associations between mental and physical outcomes were established using adjusted multivariable logistic regression models. Results Of the 531 patients followed, 108 (20%) screened positive for any MHD: of those who screened positive for PTSD (7.9%, N = 42), all had co-morbid depression and/or anxiety. In contrast, 66 patients (12.4%) screened negative for PTSD but positive for depression and/or anxiety. Compared to patients with no MHD, patients who screened positive for PTSD were more likely to have chronic pain {odds ratio (OR): 8.79 [95% confidence interval (CI): 3.21, 24.08]}, functional limitations [OR: 7.99 (95% CI: 3.50, 18.25)] and reduced physical health [β: -9.3 (95% CI: -13.2, -5.3)]. Similarly, patients who screened positive for depression/anxiety (without PTSD) were more likely to have chronic pain [OR: 5.06 (95% CI: 2.49, 10.46)], functional limitations [OR: 2.20 (95% CI: 1.12, 4.32)] and reduced physical health [β: -5.1 (95% CI: -8.2, -2.0)] compared to those with no MHD. Conclusions The mental health burden after injury is significant and not limited to PTSD. Distinguishing among MHD and identifying symptom-clusters that overlap among these diagnoses, may help stratify risk of poor outcomes, and provide opportunities for more focused screening and treatment interventions.
Millimeter Wave Imaging Array Using a Chip First Additive Manufacturing Process

This paper provides a proof-of-concept demonstration of the utilization of additive manufacturing (AM) in the fabrication of sensors for millimeter wave (mmWave) and potentially terahertz (THz) imaging applications. A chip first approach is utilized in which commercially available GaAs based Schottky diodes are mounted upon a liquid crystal polymer (LCP) substrate, after which dielectric and conductive layers are deposited via aerosol jet printing and cured/sintered to form the integrated imaging pixel element. A log periodic tooth antenna design was selected for preliminary demonstration of this procedure and yielded stable detection performance above 20 GHz, indicating the viability of combining the high-throughput, simplicity, and low-cost advantages of AM with the strict performance requirements of THz electronics.
La maturité de l'information et le processus de conception collaborative

Les processus de conception de produit comme ceux de l'industrie hydroelectrique, sont collaboratifs et sont caracterises par l'incertitude et l'interdependance des informations. En effet, certaines informations sont de sources certaines (telles que les normes), d'autres sont de sources incertaines (telles que les resultats intermediaires de conception), ou representent des hypotheses de travail que les acteurs posent afin de palier aux situations de blocage en conception. L'interdependance est une consequence de la complexite du produit et de l'organisation du processus (une multitude d'acteurs). L'incertitude et l'interdependance causent inevitablement des risques d'iteration dans la conception et par consequent, induisent des delais et des surcouts dans le projet. La question traitee dans cette these est comment ameliorer les echanges d'information et la collaboration dans les equipes projet ? L'interet est d'explorer les moyens de mieux utiliser les informations dans le processus de conception afin d'eviter les iterations. La these propose un cadre de collaboration qui englobe : (1) un modele de maturite d'information en conception, (2) un cadre d'echange d'information unifie qui considere des mecanismes de coordination et de cooperation et (3) des fonctionnalites de futur systemes de gestion d'information. Ce dernier apport represente une mise en oeuvre du cadre theorique propose dans cette these. Cette mise en oeuvre est realisee au travers un prototype d'illustration des fonctionnalites (PIQUANT) et une demarche a base de patrons.
2D patterns for 3D surface matching

Surface matching is the process that compares the shape of two surfaces. To facilitate surface matching, we have developed a 2-D representation for comparing 3-D surfaces of arbitrary shape. Using a cylindrical mapping, a descriptive pose-invariant 2-D pattern is created for every point on the surface of an object. By comparing patterns, point correspondences between different surfaces are established. When a sufficient number of point correspondences exist between two surfaces, the surfaces match. We show that the simplicity and generality of our representation makes it widely applicable to problems in 3D computer vision including object modeling, interior modeling and object recognition.
Multiparametric magnetic resonance imaging (MRI) and subsequent MRI/ultrasonography fusion-guided biopsy increase the detection of anteriorly located prostate cancers

Objective To describe the detection rate of anteriorly located prostate cancer (PCa) with the addition of magnetic resonance imaging (MRI)/ultrasonography (US) fusion-guided biopsy (FGB) to the standard transrectal ultrasonography (TRUS)-guided biopsy. Patients and Methods All patients, regardless of their biopsy history, who were referred for clinical suspicion of PCa (i.e elevated prostate-specific antigen (PSA) level and abnormal digital rectal examination) underwent 3T multiparametric-MRI (mpMRI) screening; and those with suspicious lesions in the anterior region of the prostate were identified. Patients then received a FGB of all suspicious lesions in addition to a systematic 12-core extended sextant TRUS-guided biopsy. We conducted a lesion-based analysis comparing cancer detection rates of anterior targets using FGB vs systematic cores taken from the same anatomic sextant within the prostate. Lengths of cancer in the most involved core were also compared between the two biopsy techniques used. Patients with only anterior targets were analysed separately. Results Of 499 patients undergoing FGB, 162 had a total of 241 anterior lesions. The mean age, PSA level and prostate volume in this group were 62 years, 12.7 ng/dL, and 57 mL, respectively. In total, PCa was diagnosed in 121 anterior lesions (50.2%) identified on mpMRI. Sixty-two (25.7%) of these anterior lesions were documented as positive for cancer on systematic 12-core TRUS-guided biopsy cores, while 97 (40.2%) were positive on the targeted FGB cores (P = 0.001). In lesions that were positive on both FGB and TRUS biopsy, the most involved core was 112% longer on FGB (3.7 vs 1.6 mm, P ≤ 0.01). Forty-two patients had only anterior lesions on mpMRI; of these, 24 (57.1%) were found to have cancer on the FGB + TRUS biopsy platform. Six patients were positive on FGB only and 13 were positive on both biopsy techniques; however, 7/13 patients were upgraded to a higher Gleason score after FGB. All five patients positive on TRUS biopsy only were candidates for active surveillance. Conclusion The results showed that FGB detects significantly more anteriorly located PCa than does TRUS-guided biopsy alone and it may serve as an effective tool for the subset of patients with such tumours.
Resistance to Change and the Language of Public Organizations: A Look at “Clashing Grammars” in Large-Scale Information Technology Projects

The management environment of large-scale agency information technology (IT) projects is used as a framework for examining the notion of “clashing grammars” as a form of resistance to change within public organizations. Such projects, rooted in new management disciplines from the private sector, are being initiated in broad mimetic fashion by agencies seeking improved performance. The common problems with these projects may be manifestations of resistance to the very management tools developed for their implementation. This resistance may occur inadvertently when new grammars characteristic to modern IT projects clash with more traditional grammars embedded in the culture of public organizations.
Aromatic polyamides. IV. A novel synthesis of sulfonated poly(para‐phenyleneterephthalamide): Polymerization of terephthalic acid and para‐phenylenediamine in sulfur trioxide

A novel polyamide condensation reaction of aromatic diamines (usually as strong inorganic acid salts) and aromatic diacids in SO3 has been discovered. para-Phenylenediamine was polymerized with terephthalic acid in SO3 at 20–47% polymer concentration to form highly anisotropic (liquid crystalline) sulfonated poly(p-phenyleneterephthalamide) (SPT) solutions (dopes) with inherent viscosities as high as 1.6. Sulfonation of the aromatic diamine ring was a major side reaction. The effects of reaction variables such as temperature, time, monomer concentration, stoichiometry, and solvent acidity on molecular weight were studied. The dopes were spun to fiber, but tensile properties were limited by coagulation problems associated with hydrophilicity of the highly sulfonated polymer. Thermogravimetric analysis of SPT at 20°C/min showed weight loss only above 450°C.
The role of the Roper in QCD

We show that existing data suggest a simple scenario in which the nucleon and the Δ and Roper resonances act as chiral partners in a reducible representation of the full QCD chiral symmetry group. We discuss the peculiar interpretation of this scenario using spin-flavour symmetries of the naive constituent quark model, as well as the consistency of the scenario with large-Nc expectations.
Quantifying the Structural and Mechanical Changes in Elastase Degraded Arteries as an In Vitro Model of Aortic Aneurysm

Common characteristics of aortic aneurysm include loss of elastin/smooth muscle cells, increase in fibrillary collagen, and increase in artery diameter [5]. Because of the high mortality rate of aneurysm rupture, it is desirable to be able to predict when a patient should have surgery to repair the dilated tissue. Current clinical practices involve predicting aneurysm rupture based on artery expansion rate and diameter. However, other parameters such as wall stiffness and peak wall stress may offer better predictions as to when an aneurysm will fail [8]. Previous studies have investigated the differences in elastin and collagen content of abdominal aortic tissue with and without abdominal aortic aneurysm (AAA) [1]. In another study, human aortic aneurysm tissue was tested in a biaxial tensile tester and the resulting stress strain curves were fitted using Fung type exponential strain energy function [7]. More extensive modeling of aneurysm tissue has been done by modifying the Holzapfel model to incorporate a parameter that characterizes the tissue weakening before the failure of the inner elastic laminae, ground matrix, or collagen fibers themselves [6]. Previous studies have found compositional and mechanical differences between aneurysm and healthy tissue. In addition, good structurally based models for arteries that are developing aneurysm exist but these are mostly theoretical [6]. In order to improve aneurysm rupture prediction techniques, a better understanding of how structural changes affect the mechanical properties of the artery is necessary.Copyright © 2011 by ASME
Drawing a Triangle on the Thurston Model of Hyperbolic Space

In looking at a common physical model of the hyperbolic plane, the authors encountered surprising difficulties in drawing a large triangle. Understanding these difficulties leads to an intriguing e...
Determination of the Lateral Eddy Diffusivity in the Climatological Mean Gulf Stream

The spread of positions of the Gulf Stream as exhibited in fig. I of the paper by FUGLISTER and WORTHINGTON (1951) published in this issue of Tellus suggests that one should be able to compute a rough value of the lateral eddy diffusivity produced by the meandering and shifts of position of the stream, although the number of points a t any section, taken across the stream at any distance along the axis of the stream is quite small for statistical purposes. DOI: 10.1111/j.2153-3490.1951.tb00774.x
Initial Public Offerings by Mutual Thrifts: The Regulatory Impact

This study analyzes the abnormal returns from a sample of 311 mutual thrift IPOs to investigate the presence of deliberate underpricing and to measure the impact of the changing regulatory environment. The large initial returns are maintained over the following year, indicating deliberate underpricing. Cross-sectional regressions show that the adjusted returns are positively related to the percentage of insiders participating in the IPO and to the size of the conversion. The adjusted returns significantly decrease after regulations are tightened, and there is a rapid rise in adjusted returns when uncertainty is introduced relating to the actual impact of these regulations. (JEL G280)
Dietary influence on pancreatic cancer growth by catechin and inositol hexaphosphate.

Introduction. Pancreatic cancer is an extremely virulent form of cancer with few effective treatments. Catechin and inositol hexaphosphate (IP6), two naturally occurring molecules found in green tea and high-fiber foods, respectively, are compounds that have been shown to demonstrate anti-proliferative effects when administered as single therapeutic agents against a number of cancers. We hypothesized that, alone and in combination, IP6 and catechin would be effective against pancreatic cancer. Materials and methods. Pancreatic (PANC-1 and MIAPACA) cancer cell lines were cultured and treated with IP6 (0.8 mM/well), catechin (100uM/well), and the combination of the two. Cell viability was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) at 24,48, and 72 h. Vascular endothelial growth factor (VEGF) was measured in the cell supernatants by ELISA. Apoptosis was evaluated by Annexin V-fluorescein isothiocyanate (FITC). Results. The combination of catechin and IP6 significantly inhibited proliferation in the PANC-1 cell line at 24, 48, and 72 h compared to single agents (P < 0.001). Growth of the MIAPACA cell line was inhibited (P < 0.01) by each agent alone, but additive inhibitory effects were not seen. An increase in early apoptosis was attributed to catechin therapy in both cell lines (P < 0.01). The combination of these agents also increased early apoptotic activity when compared to the control (P < 0.001). IP6 reduced VEGF in both cell lines (P < 0.01). In combination, catechin and IP6 amplified VEGF reduction compared to each agent in MIAPACA and control (P < 0.002). Conclusions. These results, combined with the prevalence of these compounds in safe, naturally occurring foods, make catechin and IP6 attractive therapies for treatment, and possibly in preventative trials, of pancreatic cancer.
[Comment on “Large‐scale concentration and conversion of solar energy” by Hildebrandt, et al.] Comment on “solar energy”

In the July issue of EOS, Hildebrandt, Haas, Jenkins, and Colaco have presented an interesting technical exercise by developing the design for a solar-powered electrical generating system using steerable Fresnel mirrors and a fixed boiler [‘Large Scale Concentration and Conversion of Solar Energy,’ p. 684]. They suggest that such an arrangement could be capable of supplying the bulk of United States energy needs in the year 2000, but their economic analysis has not considered several important aspects of the overall logistics. For want of a better source, this note will draw upon the applicable numbers in their paper and will be confined largely to re-examination of certain aspects of the overall feasibility.
A Substance Resembling Arginine Vasotocin in the Anterior Pituitary Gland of the Cockerel

Fractionation by ultrafiltration of acid extracts of cockerel adenohypophyses revealed 2 components which depleted ovarian ascorbic acid (OAA) in the appropriately pretreated assay rat. Avian LH was retained in the large molecular weight (over 12,000) fraction. In the 32P assay, this fraction evoked a response curve which was parallel to that of the NIH-LH standard. The other fraction, which contained molecules with a molecular weight of less than 12,000, caused depletion of OAA in both intact and hypophysectomized assay rats, but was inactive when tested for its ability to increase 32P uptake by the chick testis. Thus, its OAA depleting activity was due neither to luteinizing hormone (LH) nor to LH-releasing factor. Fractionation of the small molecules on a column of Sephadex G-25 revealed a potent OAA depleting compound with the additional following characteristics: 1) same elution volume as synthetic arginine vasotocin (AVT), 2) potent vasopressor activity, 3) inactivated by thioglycollate. These data ...
Effect of Aerosil Gels on de Gennes Nematic−Smectic Coupling†

There is a well-known de Gennes coupling between the scalar nematic order parameter S and the smectic density-wave amplitude |Ψ|, which causes the nematic−smectic-A phase transition to cross over from second order to first order via a tricritical point. This sort of crossover is observed for numerous liquid crystals (LCs) with small to moderate nematic ranges. Recent studies of LC+aerosil systems, where the aerosil particles form a soft thixotropic gel, have shown that such aerosil gels can greatly reduce or completely suppress this coupling. The underlying LC critical exponents once de Gennes coupling is absent are discussed and compared with theory.
Rapidity gaps and jets as a new-physics signature in very-high-energy hadron-hadron collisions.

In hadron-hadron collisions, production of Higgs bosons and other color-singlet systems can occur via fusion of electroweak bosons, occasionally leaving a ``rapidity gap'' in the underlying-event structure. This observation, due to Dokshitzer, Khoze, and Troyan, is studied to see whether it serves as a signature for detection of the Higgs bosons, etc. We find it is a very strong signature at subprocess c.m. energies in excess of a few TeV. The most serious problem with this strategy is the estimation of the fraction of events containing the rapidity gap; most of the time the gap is filled by soft interactions of spectator degrees of freedom. We also study this question and estimate this ``survival probability of the rapidity gap'' to be of order 5%, with an uncertainty of a factor 3. Ways of testing this estimate and further discussion of the underlying hard-diffraction physics are presented.
The Impact of Federal Bioterrorism Funding Programs on Local Health Department Preparedness Activities

Using the 2005 National Association of County and City Health Officers Profile of Local Health Departments data set, bivariate probit and Heckman selection models were used to test the hypothesis that the level of federal funding received for bioterrorism preparedness is related to the preparedness activities undertaken by local health departments. Overall budget, leadership, and crisis experience are found to be the most important determinants of local preparedness activity, but Centers for Disease Control and Prevention preparedness funding plays a mediating role by building capacity through the hiring of one key leadership position, the emergency preparedness coordinator. Additional research is needed to determine the potential impact of these funds on other aspects of the local public health system, such as the scope of services delivered, to determine secondary effects of the program.
A general tetrakaidecahedron model for open-celled foams

Abstract A micro-mechanics model for non-isotropic, open-celled foams is developed using an elongated tetrakaidecahedron (Kelvin model) as the repeating unit cell. Assuming the cell edges possess axial and bending rigidity, the mechanics of deformation of the elongated tetrakaidecahedron lead to a set of equations for the Young’s modulus, Poisson’s ratio and tensile strength of the foam in the principal material directions. These equations are written as a function of the cell edge lengths and cross-section properties, the inclination angle and the strength and stiffness of the solid material. This micro-mechanics model employs an elongated Kelvin model geometry which is more general than that employed by previous authors, as the size and shape of the repeating unit cell are defined by specifying three independent dimensions. As a result, the model accounts for an additional variation in the unit cell shape which is not accounted for in the previous models. The effect of this additional shape parameter on the non-isotropic stiffness and strength behavior is demonstrated and the advantages of this more general micro-mechanics model are illustrated.
Mechanical performance of ceramic matrix composite I-beams

Abstract Experimental studies have been performed on ceramic matrix composite (CMC) I-sections, which typify joint designs for CMC components. Axial loads and moments have been applied to activate delamination mechanisms. The maximum load bearing capacity has large variability, governed by the severity of manufacturing flaws located in the transition region of the I-section. This variability leads to an unsatisfactory design situation. Delaminations that form from these flaws arrest and behave in a stable manner, subject to a remanent load bearing capacity. This remanent capacity has minimal variability. Hence, design based on the remanent load would be robust. An expression for this design criterion is presented.
Pre mortem analysis of lung injury and lung function in oxygen toxic rabbits.

Objectives To determine whether respiratory system mechanics measurements could detect lung injury in oxygen toxic rabbits before clinical deterioration. To determine whether respiratory system mechanics measurements, using a power analysis, have the statistical power to detect significant reductions in hyperoxic lung injury due to an intervention when compared with traditional post mortem measurements of lung injury, extravascular lung water, and bronchoalveolar lavage protein concentration. Design Prospective, controlled study. Setting Institutional animal laboratories. Subjects Adult New Zealand white rabbits. Interventions Spontaneously breathing adult New Zealand white rabbits were exposed continuously to either > 95% oxygen or room air. Measurements and main results We measured arterial pH, blood gas tensions, and respiratory system mechanics in rabbits twice, both before exposure to > 95% oxygen, and after the rabbits developed symptoms of mild lung dysfunction. After the second set of respiratory system mechanics measurements, we measured extravascular lung water and bronchoalveolar lavage protein concentration in the hyperoxia-exposed rabbits and compared the values with those values obtained in animals that breathed room air only. Our hyperoxia-exposed rabbits developed symptoms of mild respiratory impairment at 69 +/- 2 hrs. In these hyperoxia-exposed rabbits, measurements of static compliance, quasi-static compliance and resistance all changed significantly (p Conclusions Measurements of respiratory system mechanics can detect lung injury in hyperoxic rabbits before the onset of severe clinical deterioration or death. Furthermore, measurement of static compliance of the respiratory system is likely to be a powerful tool to detect a reduction in lung injury produced by an intervention.
Oscillations in stomatal conductance of hybrid poplar leaves in the light and dark

Cycling of stomatal conductance in three hybrid poplar (Populus sp.) cultivars was observed under a variety of conditions. Illumination of plants kept previously in the dark induced very large oscillations with a period of about 40 min and large oscillations with a shorter period (< 10 min) were superimposed on the longer cycles. During these oscillations, large changes in conductance could occur very rapidly (1.0 cm s−1 in 3 min). Plants in constant light also displayed both long and short term cycles in conductance, but these were smaller in amplitude than those induced by sudden illumination. Stomatal oscillations were also observed in darkness and after darkening of previously illuminated plants. These oscillations had shorter (< 30 min) and less regular periods than those observed in the light. Such cycling in the dark is rare. Cycling of the two leaf surfaces was sometimes in synchrony in the light, and more so after a perturbation. Little synchrony between the two surfaces was observed in the dark. Stomatal movements of different leaves on a plant were usually relatively independent. Transient stomatal opening occurred following leaf excision in the light or dark, and often after sudden darkening of intact leaves. Also, stomata of intact leaves sometimes transiently closed following illumination.
Drug discrimination using a Pavlovian conditional discrimination paradigm in pigeons.

Abstract Three pigeons were studied using a discriminated autoshaping procedure in which the presence or absence of methadone served as a conditional stimulus signalling which of two key light CSs would be followed by grain access. Drug sessions alternated randomly with no-drug sessions. Methadone (2.0 mg/kg) was administered prior to drug sessions in which a black vertical line on a white background served as CS+ and a diffuse white keylight served as CS− (reversed for bird 681). Saline or no injection was administered prior to no-drug sessions and the CS + CS − contingencies were reversed. Discriminated performances emerged in which over 80% of the responding occurred to the appropriate stimulus. Stimulus control by methadone was assessed by presenting a range of methadone doses during 10-trial extinction sessions. A graded dose-effect curve was produced with low doses of methadone controlling saline-appropriate responding and higher doses controlling drug-appropriate responding. A range of doses of morphine, cocaine, and pentobarbital were also tested. Morphine produced methadone-appropriate responding while cocaine and pentobarbital did not.
Corneal endothelial cell degeneration in a German shepherd dog

The replacement of the normal endothelial cell morphology with formation of a fibrocellular posterior collagenous layer by the corneal endothelium was demonstrated in an eight-year-old male German shepherd dog with bilateral progressive corneal oedema. Descemet's membrane was multilaminar and thickened. The ultrastructural findings in this dog are similar but not identical to histological changes present in several human corneal diseases.
Sea-floor spreading in marginal basins of the Western Pacific☆

Abstract Observed magnetic lineations from the Shikoku, South Fiji, and West Philippine marginal basins are used to determine aspects of the tectonic evolution of these basins. In the western part of the Shikoku basin, anomalies 7 through 5E (~ 27-19 m.y. B.P.) are identified between the base of the Palau-Kyushu ridge and the center of the basin. In the eastern part of the South Fiji basin, anomalies 12 through 8 (~ 35-29 m.y. B.P.) are identified between the base of the Lau-olville ridge and the center of the basin. In the West Philippine basin, magnetic lineations which trend ESE—WNW have been mapped north of the Central Basin Fault. These lineations and the previously mapped lineations south of the fault (Louden, 1976) may be one limb of a Mesozoic spreading system, but more probably represent a two-limb system of Early Tertiary age.
The origin and function of self-incompatibility in flowering plants

The evolutionary significance of self-incompatibility (SI) traditionally has been linked to reduced inbreeding through enforced outcrossing. This view is founded on the premise that outcrossing reduces inbreeding. It is important, when considering the evolutionary significance of any genetic system, to try to distinguish those factors related to the evolution of, from those related to the maintenance of, the system in question. Three factors are considered important for the maintenance of SI: (1) phylogenetic constraint in species descended from SI ancestors, (2) reduced inbreeding in populations, and (3) fitness benefits to individuals resulting from the avoidance of selfing. I suggest that the first two factors should be rejected when considering the origin of SI (whether one or more origins are hypothesized) and that the increase in individual fitness resulting from the avoidance of self-fertilization among individuals that are heterozygous for deleterious alleles may be sufficient to account for the origin of SI. Self-fertilization in plants (except in species that predominantly self-fertilize) generally results in a reduction in fitness of some individuals due to the increased expression of deleterious or lethal recessive alleles, regardless of the degree of inbreeding in the population or the frequency of the allele in question. Inbreeding is a consequence of population structure in many outcrossing plant species. Complex (multi-locus and multi-allelic) systems of SI exist that reduce inbreeding. However, it is argued that these are derived either from simpler systems of SI that may have very little or no effect on inbreeding, in which case any effect on level of inbreeding is secondary, or are not true self-incompatibility systems and are part of a regulatory system that serves to balance the level of inbreeding and outbreeding. Multi-locus and multi-allelic systems of SI and heteromorphic systems of SI are discussed in terms of derived versus ancestral characteristics. A reassessment of the role of breeding systems in the development of a population structure promoting inbreeding is suggested, which may have been of crucial importance in the success and diversification of angiosperms.
The color of dragline silk produced in captivity by the spider Nephila clavipes

Fifty-six N. clavipes spiders from the same region of Florida were kept in captivity under the same conditions and fed a similar diet of crickets. Their major ampulate glands were forcibly silked. Dates, silking times, and the colors of the dragline silk produced were recorded. The colors ranged from all white through various combinations of white and yellow upon different silkings to all yellow. If a spider had been producing white silk for at least 4 h, the color being produced could suddenly change to yellow 38% of the time. These observations indicate that factors beyond diet and environment influence the color of silk produced in captivity by forcible silking. They also indicate that the spiders store both pigmented and unpigmented silks and that some aspect of forcible silking precludes the spiders' choosing the color. The yellow and white silks exhibit similar exterior surface morphologies as well as similar tensile properties.
TU-E-BRB-11: End-To-End Positioning Quality Assurance for Image-Guided Radiosurgery of Multiple Targets Using a Single-Isocenter.

Purpose: Using a single isocenter significantly reduces delivery times in radiosurgery involving multiple targets. However, because not every target can be placed at isocenter with this type of treatment, a conventional Winston‐Lutz test cannot be used. We describe a novel Winston‐Lutz like mulitarget test (MTT) for verifying accurate positioning. Methods: A target phantom, comprised of an acrylic plate with recesses for three 3/4″ spheres was constructed and a high‐resolution (0.5×0.5×0.8 mm) CT scan obtained with PTFE spheres placed in the recesses. The scan was imported into a commercial treatment planning system and multiple beams were prepared, having their isocenter at the centroid of the arrangement of spheres. Every beam incorporated three MLC‐defined rectangular apertures that circumscribed the spheres. Custom software selected setup parameters (table, gantry and collimator angle, MLC openings) such that the spheres were centered as precisely as possible within their respective MLC fields, considering the discrete width of collimator leaves. The phantom, with the PTFE replaced by steel spheres, was placed on the treatment couch and imaged using stereoscopic x‐ray beams. A 6 degree‐of‐freedom robotic couch applied translations and rotations to reproduce the CT position. A MV EPID rendered images of the spheres within their respective apertures, allowing identification of sphere and aperture centers. Any error upstream would manifest itself as inaccurate centering of a sphere. Results: Eight beams with table angle 0 and two beams each with table angles 49.7, 89.8, 272.3, and 310.1 were selected. The maximum calculated distance between any sphere and the respective aperture center was 0.07 mm. The median difference measured from the MV images ranged from 0.1 mm to 1.4 mm with a median of 0.8 mm. Conclusions: The MTT is a practical end‐to‐end test for quality assurance of the entire positioning process in multitarget radiosurgery, from CT scanning to beam delivery.
Exposure to asbestos in the use of consumer spackling, patching, and taping compounds

Analysis of representative samples of spackling, patching, and jointing compounds, purchased at retail stores in the New York City area, has shown that some contain asbestos minerals as well as other biologically active substances. Measurements suggest that home repair work involving the use of such materials may result in exposure to dust at concentrations sufficient to produce disease.
A comparison of the toxicity of snake venom phospholipase and lysolecithin

Abstract The toxicities of snake venom phospholipase and purified lysolecithin compared in mice. The phospholipase is 256 times as toxic (LD 50 ) as the lysolecithin. It is suggested that the accepted mechanism of toxicity snake venom phospholipase, be re-examined.
The significance of shift Work : Current status and future directions

This paper provides a review and synthesis of research literature on the effects of shift work on workers’ physical health, mental health/well-being, and family life. The focus is on current knowledge, unanswered questions, and new directions for future research. The selection of research literature is guided by a general conceptual framework that identifies predictor variables, moderating variables, and outcome variables. The paper concludes with a discussion of the variables that should be incorporated into an agenda for future research.
Z-STEM of L1o Ordering in FePt Magnetic Nanoparticles

The L1{sub o} (CuAuI) ordered FePt structure exhibits exceptional magnetic properties with uniaxial-magnetocrystalline anisotropy (K{sub u}) greater than 10{sup 6} ergs/cm3. Chemical synthesis methods can produce monodispersed FePt nanoparticles that have diameters ranging from 3 to 10 nm with a standard deviation of less than 5%. As-synthesized, the FePt nanoparticles are face-centered cubic (FCC) and require annealing at temperatures greater than 550 C for chemical ordering into the L1{sub o} structure. X-ray diffraction (XRD) methods typically characterize the ordering phase transformation by measuring the superlattice peaks. However, since the FePt nanoparticles coarsen during annealing, the larger particles may dominate the XRD data while the smallest particles correspondingly may contribute little to the diffracted intensity. Since recent data suggest that the FePt L1{sub o} ordering transformation is particle-size dependent, the current study employs high-angle annular dark-field (HAADF) scanning transmission electron microscopy (STEM), also known as atomic-number contrast or Z-STEM, methods to investigate the presence of L1{sub o} order in individual FePt nanoparticles.
Deep convection in the Japan (East) Sea: A modeling perspective

[1] The Japan (East) Sea (JES) is a region of intense air-sea interactions. Recent observations show deep open ocean convection occurring south of Vladivostok near the subpolar front to a depth of roughly 1000 m during the winter of 2000, with even more intense convection during the extremely cold winter of 2001. In this region, wintertime cold continental air outbreaks, combined with strong very cold mountain-gap winds give rise to deep convection and Intermediate Water Formation. We have reproduced the 2000 event in a three dimensional numerical model and examine its onset and evolution, thus shedding some more light on this important process. The study demonstrates that the confluence of warm and cold water masses at the subtropical front south of Vladivostok is the preferred location of deep convection events in JES, as the confluence-induced downwelling assists in the deeper penetration of the convective turbulence generated by strong wintertime cooling.
Botulinum neurotoxin devoid of receptor binding domain translocates active protease

Clostridium botulinum neurotoxin (BoNT) causes flaccid paralysis by disabling synaptic exocytosis. Intoxication requires the tri-modular protein to undergo conformational changes in response to pH and redox gradients across endosomes, leading to the formation of a protein-conducting channel. The ∼50 kDa light chain (LC) protease is translocated into the cytosol by the ∼100 kDa heavy chain (HC), which consists of two modules: the N-terminal translocation domain (TD) and the C-terminal Receptor Binding Domain (RBD). Here we exploited the BoNT modular design to identify the minimal requirements for channel activity and LC translocation in neurons. Using the combined detection of substrate proteolysis and single-channel currents, we showed that a di-modular protein consisting only of LC and TD was sufficient to translocate active protease into the cytosol of target cells. The RBD is dispensable for cell entry, channel activity, or LC translocation; however, it determined a pH threshold for channel formation. These findings indicate that, in addition to its individual functions, each module acts as a chaperone for the others, working in concert to achieve productive intoxication.
Characteristic Polynomials by Diagonal Expansion

Abstract This article describes the method of expansion by diagonal elements for the evaluation of the determinant of the sum of two square matrices, one of which is diagonal. This result is applied to the problem of obtaining the characteristic polynomial of a square matrix. For problems of interest in statistics, this technique is frequently much more direct than the usual approach of simplification (e.g., triangularization) by elementary row and column operations. Several examples are presented.
Sources of electrical transients in tectal neuropil of the frog, Rana pipiens.

We have studied the outer neuropil layers in frog tectum where the unmyelinated optic nerve fibers terminate. At any point in the neuropil an extracellular microelectrode records several different visually evoked electrical transients, distinct by size and shape. When classified by shape alone, each transient falls into one of 3 distinct classes. Some of these transients are binocularly driven, as originally described by Finch and Collett. The aggregate of the receptive fields of all the elements recorded at a single point defines a multiunit receptive field (MURF). Each MURF is characteristically oval, and divided into 3 sections along its long axis. Each section represents the aggregate of the receptive fields associated with one class of transient; i.e. transients belonging to only one specific class can be evoked by stimulating that part of the visual field corresponding to the appropriate section of the MURF. All of the MURFs mapped by recording in a single tectum are radially arranged in visual space about a central point, or 'visual pole'. Several conclusions are made. First, the two larger types of transient are generated postsynaptically by electrically active dendritic elements, specifically the beaded dendritic appendages of tectal neurons. The smallest type of transient is of presynaptic origin. Second, these tectal elements have a local and global anatomical order across the tectum, which accounts for both the tripartite structure of the MURFs and their radial arrangement about a visual pole. Third, since the large transients are of postsynaptic origin, genuine recordings of single retinal ganglion cell (RGC) activity can be made only in the optic nerve or retina itself. Fourth, information is conveyed over the unmyelinated optic nerve fibers at pulse rates as high as 80/s and is transsynaptically effective at such rates. Finally, the electrically active tectal dendritic elements, with their highly organized spatial arrangement, are an important component of the frog's visual processing apparatus, instead of being merely relays or repeaters.
Assessment of depositional ash loadings from the 2009 eruption of Mt. Redoubt

Abstract Volcanic ash deposited onto ice and snow in the Arctic has the potential to perturb the regional radiation balance by altering the surface reflectivity. In order to determine changes in surface albedo, loading fields of deposits must be quantified. Loading fields are defined as the total mass of ash deposited over an area. We assessed the areal extent and loading of ash deposits from the 2009 eruption of Mt. Redoubt using an Eulerian volcanic ash transport and dispersion model, Fall3D, combined with satellite and deposit observations. Because direct observations are often limited in remote Arctic regions, we devised a novel method for modeling ash deposit loading fields for the entire eruption based on best-fit parameters of a well-studied eruptive event. The major land-depositing eruptive events (events 2–6 on March 23–24) were chosen for analyses. Realistic ranges of model parameters were selected based on the well-described event 5 (March 23) and were estimated for other events. The model results were validated against NASA A-train satellite data and field measurements reported by the Alaska Volcano Observatory. Overall, good to moderate agreement was found. A total cumulative deposit area of 3.7 × 106 km2 was produced, and loadings ranged from ~ 7000 ± 3000 g m− 2 near the vent to
Symplectic integration of Hamiltonian systems

The authors survey past work and present new algorithms to numerically integrate the trajectories of Hamiltonian dynamical systems. These algorithms exactly preserve the symplectic 2-form, i.e. they preserve all the Poincare invariants. The algorithms have been tested on a variety of examples and results are presented for the Fermi-Pasta-Ulam nonlinear string, the Henon-Heiles system, a four-vortex problem, and the geodesic flow on a manifold of constant negative curvature. In all cases the algorithms possess long-time stability and preserve global geometrical structures in phase space.