cssi/SciSciGPT-SciSciNet huggingface dataset:
U.S. Regulatory Considerations for Heart Valves Implanted by Minimally Invasive Surgery

The United States Food and Drug Administration (FDA) regulates medical devices to ensure their safety and effectiveness. Prosthetic heart valves implanted by minimally invasive surgery are Class III life supporting and life sustaining devices that are covered by the IDE and PMA regulations. FDA recently published a draft heart valve guidance document (HVGD) for public comment, which is primarily intended for heart valves implanted by open chest, open heart surgery. The HVGD is intended to supplement ISO 5840:2005 and both of these documents serve as a good basic starting point for testing requirements for percutaneous heart valves (PHV). FDA has worked interactively in the drafting of a new ISO standard for PHV, which could ultimately be recognized by the FDA. In regulating PHV, FDA is concerned with identifying the proper boundary conditions for in vitro testing, and with the use of new materials such as Nitinol in the dynamic environment of heart valve implantation sites. FDA also believes that complete in vivo data answering questions that a clinical trial can typically not address, and demonstrating that a valve can be reliably delivered and is reasonable safe, is essential before a first in man study. A robust clinical trial design is critical to a premarket review of PHV, and the current evidence base dictates that PHV be studied in randomized controlled trials, comparing the PHV to the treatment a patient would have otherwise received. As always, FDA reviews the totality of data available for a particular device when making approvability decisions.
Athens and Tenos in the Early Hellenistic Age

Some recent work on the history of Athens and Tenos in the third century B.c. has brought to light new evidence and new interpretations of old evidence for this notoriously shadowy period of Greek history. Reflection on this material has suggested to me solutions to a few minor puzzles (Sections IA, IB, III), a contribution to a long-standing problem in the history of Athens in the early third century (Section IB), and a new explanation for the entry of Rhodos into the war with Antiokhos (Section II).
The rapid activation of N-Ras by α-thrombin in fibroblasts is mediated by the specific G-protein Gαi2–Gβ1–Gγ5 and occurs in lipid rafts

Abstract α-thrombin is a potent mitogen for fibroblasts and initiates a rapid signal transduction pathway leading to the activation of Ras and the stimulation of cell cycle progression. While the signaling events downstream of Ras have been studied in significant detail and appear well conserved across many species and cell types, the precise molecular events beginning with thrombin receptor activation and leading to the activation of Ras are not as well understood. In this study, we examined the immediate events in the rapid response to α-thrombin, in a single cell type, and found that an unexpected degree of specificity exists in the pathway linking α-thrombin to Ras activation. Specifically, although IIC9 cells express all three Ras isoforms, only N-Ras is rapidly activated by α-thrombin. Further, although several Gα subunits associate with PAR1 and are released following stimulation, only Gα i2 couples to the rapid activation of Ras. Similarly, although IIC9 cells express many Gβ and Gγ subunits, only a subset associates with Gα i2 , and of those, only a single Gβγ dimer, Gβ 1 γ 5 , participates in the rapid activation of N-Ras. We then hypothesized that co-localization into membrane microdomains called lipid rafts, or caveolae, is at least partially responsible for this degree of specificity. Accordingly, we found that all components localize to lipid rafts and that disruption of caveolae abolishes the rapid activation of N-Ras by α-thrombin. We thus report the molecular elucidation of an extremely specific and rapid signal transduction pathway linking α-thrombin stimulation to the activation of Ras.
Dynamics of the bcc→hcp transition in crystals under uniaxial stress

Molecular-dynamics simulations of a model alkali metal under $⟨100⟩$ uniaxial load reveal a fundamental understanding of the atomistic kinematics and dynamics of the stress induced $\text{bcc}\ensuremath{\rightarrow}\text{hcp}$ lattice structural transition. The transformation itself is ``Burgers-type,'' with opposing shearing of alternate {110} planes; however, shearing occurs on the {110} planes of zero shear stress. The results, including the singular nature of the lattice-parameter variations at the inception of the transition, are analyzed and explained within the framework of crystal elastic stability theory.
The Problem of Evil, the Social Contract, and the History of Ethics

This review article discusses five essays from the recently published Reclaiming the History of Ethics: Essays for John Rawls, and argues they are united with Rawls's own recent work by a concern to address an unduly neglected aspect of the traditional problem of evil, which is whether humanity is worthy of existence given the evil of which we are capable, suggesting that the social contract tradition can be understood historically as attempting to deal with this problem.
Drillhole results to be discussed

Vattenfall, the Swedish State Power Board, is searching for a predicted reservoir of abiogenic methane beneath the floor of a meteorite crater in central Sweden. Some of the early scientific results from the drilling project at the Siljan Ring impact structure will be presented on Thursday, May 21, at the 1987 AGU Spring Meeting in Baltimore, Md. Thomas Gold of Cornell University (Ithaca, N.Y.) has predicted that large amounts of methane from deep within the earth may move closer to the surface beneath sites where large meteorites have hit the earth, such as the Siljan Ring structure (Eos, July 9, 1985, p. 537). The site is known for its gas seeps, according to Paul Westcott of the Gas Research Institute (GRI, in Chicago, Ill.). The institute is putting up 15% of the costs of the drillhole in return for access to samples and data. Seismic surveys at the site revealed horizontal structures in the granite, which may suggest the presence of gas-liquid interfaces, Westcott said.
Reversing the tide of tuberculosis in India: complementing microscopy with line probe assays

Abstract In 1993, the World Health Organisation (WHO) declared tuberculosis (TB) a global health threat, adopted the Directly Observed Therapy – Short Course (DOTS) strategy, and set two targets for control and elimination of the disease: to detect 70% of sputum smear positive cases and to successfully treat 85% of those cases. The recommended diagnostic tool under DOTS remains sputum smear microscopy, a simple, yet ineffective, technique that only detects roughly half of TB cases. In India, where TB killed 450,000 people in 2005, both WHO targets for detection and treatment were met in the smear positive population covered by DOTS. However, HIV co-infection and multidrug-resistant TB (MDR-TB) pose formidable threats to TB control: TB in HIV-positive patients is often smear-negative, and microscopy cannot detect drug resistance. Although, the reliance on DOTS has proven effective in areas where both HIV prevalence and drug resistance are low, in India, the National TB Programme should consider complementi...
Panic disorder versus panic disorder with major depression: Defining and understanding differences in psychiatric morbidity

The present study examined the impact of comorbid major depressive disorder (MDD) on psychiatric morbidity, panic symptomatology and frequency of other comorbid psychiatric conditions in subjects with panic disorder (PD). Four hundred thirty-seven patients with PD were evaluated at intake as part of a multicenter longitudinal study of anxiety disorders; 113 of these patients were also in an episode of MDD. Patients were diagnosed by DSM-III-R criteria utilizing structured clinical interviews. The 113 PD/MDD patients were compared with the 324 remaining PD subjects regarding panic symptoms at intake, sociodemographic, quality of life and psychiatric morbidity variables. Differences in frequency of other comorbid Axis I psychiatric disorders were assessed at intake; personality disorders were evaluated twelve months after intake. The results revealed the PD/MDD patients exhibit increased morbidity and decreased psychosocial functioning as compared to PD patients. Personality disorders were more prevalent in the PD/MDD group at six month follow-up assessment; the PD/MDD group also had an increased frequency of posttraumatic stress disorder (PTSD) and more comorbid Axis I anxiety disorders as compared to the PD group. The total number and frequency of panic symptoms was highly consistent between the two patient groups.
Three further naphthoquinones produced by Fusarium solani

Abstract Three naphthoquinone pigments are described which were produced by Fusarium solani . They are 2,3-dihydro-5,8-dihydroxy-6-methoxy-2-hydroxymethyl-3-(2-hydroxypropyl)-1,4-naphthalenedione, 2,3-dihydro-5-hydroxy-4-hydroxymethyl-8-methoxy-naphtho[1,2-b]furan-6,9-dione and 5,8-dihydroxy-2-methoxy-6-hydroxymethyl-7-(2-hydroxypropyl)-1,4-naphthalenedione. One of these pigments was shown to be the precursor of the other two.
Nuclear receptors CAR and PXR in the regulation of hepatic metabolism

The nuclear receptors CAR and PXR were first characterized as xenosensing transcription factors regulating the induction of phase I and II xenobiotic-metabolizing enzymes as well as transporters in response to exogenous stimuli. It has now become clear, however, that these receptors cross-talk with endogenous stimuli as well, which extends their regulation to various physiological processes such as energy metabolism and cell growth. As recognition of the function of these receptors has widened, the molecular mechanism of their regulation has evolved from simple protein-DNA binding to regulation by complex protein-protein interactions. Novel mechanisms as to how xenobiotic exposure alters hepatic metabolic pathways such as gluconeogenesis and beta-oxidation have emerged. At the same time, the molecular mechanism of how endogenous stimuli, such as insulin, regulate xenobiotc metabolism via CAR and PXR have also become evident.
Electrical responses by guinea pig megakaryocytes.

THE striking similarities between blood platelets and muscle cells elucidated in recent years (for example, contractile properties, a full complement of contractile proteins, a dual canalicular system resembling the sarcoplasmic reticulum of muscle, and an active intracellular calcium pump; for review see ref. 1) suggests that the platelet might also manifest electrical activity resembling that seen in muscle. Unfortunately, the small size of the platelet (2–4 µm in diameter) has precluded study of transmembrane electrical potentials using available techniques. However, as circulating platelets represent cytoplasmic fragments of the much larger megakaryocytes, we reasoned that the megakaryocyte itself might well possess interesting electrophysiological properties. The studies described here represent our initial characterisation of membrane responses in the megakaryocyte.
One and two photon optogalvanic spectroscopy of argon and neon for the wavelength calibration in the near infrared

The one photon and two photon optogalvanic spectra of argon and neon have been investigated in the near infrared region between 735 and 781 nm. About 35 transitions have been recorded by illuminating a hollow cathode discharge with a pulsed Ti:sapphire laser. These transitions can serve as a convenient way to calibrate Ti:sapphire laser or optical parametric oscillator radiation in this important spectral range.
Communication in the Physical and the Social Sciences

Although composed of similar elements and structured similarly, the communications systems associated with the physical sciences and the social sciences differ markedly with respect to the operation and use of these elements. For both groups of disciplines, as information flows through the system it encounters lags and filtering, and much of a scientist's communication behavior is an effort to compensate for these factors. Because the lags and filtering within each system differ in loci and extent, the members of different disciplines adjust to them differently, and the overall information flow patterns in the physical and in the social sciences differ.
Unilateral Influence on International Bureaucrats: An International Delegation Problem !

The conventional wisdom emphasizes agency slack or bias as the central problem of international delegation. I show that the possibility of a unilateral influence contest is equally problematic. States can exert unilateral influence on autonomous international bureaucrats, either through rewards or through punishments, to pursue their particular interests. A costly contest results, so some states could refuse to delegate because they expect others to be too influential. The analysis has four counterintuitive empirical implications. First, international agreements often favor institutionally weak states that are disadvantaged in the unilateral influence contest. Second, states could limit the autonomy of an international organization even if this prompts bad policies. Third, a state can sometimes profitably exchange distributional concessions for autonomy. Finally, constraints on unilateral influence are possible only if a disadvantaged state can credibly commit to compensating an advantaged state for it. A...
Anagrelide hydrochloride and ruxolitinib for treatment of polycythemia vera

Introduction: New treatment options for polycythemia vera (PV) have recently become available. This article reviews current treatment strategies for PV with a focus on anagrelide and ruxolitinib.Areas covered: The current treatment of PV is directed towards reducing the risk of additional thrombotic events. In addition to phlebotomy and aspirin, patients who are believed to have high-risk disease also receive cytoreductive therapy. Hydroxyurea (HU) and PEG-IFN are most commonly used first-line treatments. The use of anagrelide in PV is limited to situations where patient develops thrombohemorrhagic episodes in the setting of extreme thrombocytosis. The role of ruxolitinib in treatment of PV has not been fully established but based on a recently completed Phase III trial it will likely serve as a second-line option for patients with systemic symptoms.Expert opinion: HU and PEG-IFN are frontline therapies for patients with high-risk PV. Anagrelide use should be restricted to patients with clinical consequen...
Differences in epithelial enzyme activity in the duodenum, jejunum, and ileum of the monkey

Proximal duodenum, midjejunum, and distal ileum specimens were studied from 13 monkeys for nonspecific esterase, alkaline and acid phosphatases, leucine aminopeptidase, and reduced NAD and NADP dehydrogenases. In all animals and with all reactions, the epithelial cell activity was noted in the midgut and, depending upon the enzyme, the least activity in either the proximal duodenum or distal ileum.
Line tension on approach to a wetting transition

Abstract The region of three-phase contact of a binary fluid system described by a model free energy functional is studied using a mean-field density-functional approach. A first order wetting transition is induced by varying a parameter that is the controlling field variable in the model. The surface tensions of the constituent two-phase interfaces are evaluated for a range of parameter values and used to locate the wetting transition. The behavior of the line tension upon approach to the wetting transition is then determined by numerical solution of the Euler–Lagrange equations for the full three-phase system at each value of the parameter. The line tension is found to converge to a finite value as the contact angle vanishes, with a derivative that is finite with respect to contact angle but divergent with respect to the field variable (parameter), apparently growing as the inverse square root of the difference between the field variable and its value at wetting. Except for a possible logarithmic factor, which could not be discerned at the present level of numerical precision, this would be in accord with the prediction from mean-field theory.
Adsorption of oxygen and hydrogen on Au(110)-(1 × 2)

Abstract The adsorption of O2 on clean Au(110)-(1 × 2) has been studied at O2 pressures up to 1400 Torr, and temperatures between 300–500 K. Under no circumstances was any dissociative adsorption of O2 observed by temperature programmed desorption or Auger electron spectroscopy. This result is in contrast to work on supported gold catalysts, where O2 exposures of 3 to 6 Torr at 200°C are used to measure gold surface area [1–4]. In the presence of a hot mass spectrometer filament, oxygen adatoms could be generated. The recombinative desorption of oxygen atoms occured at 590 K. At certain coverages, first order kinetics for O2 desorption was observed with an activation energy of 132 kJ/mol and a pre-exponential factor of 1.3 × 1012 s−1. Adsorbed oxygen atoms could be reacted with H2 gas with a probability of less than ≈ 6 × 10−7, consistent with a Langmuir-Hinshelwood mechanism and a very low dissociative sticking probability for H2. Hydrogen adatoms, generated at 150 K by dosing H2 with the mass spectrometer filament on, associatively desorbed at 216 K. In the absence of a hot filament, hydrogen could not be dissociatively adsorbed.
Holmium:YAG laser coronary angioplasty in acute myocardial infarction

Patients who sustain complicated acute myocardial infarction in whom thrombolytic agents either fail or are contraindicated often need mechanical revascularization other than PTCA. In 24 patients with acute infarction complicated by continuous chest pain and ischemia who either received lytics or with contraindication to lytics, a holmium:YAG laser (Eclipse Surgical Technologies, Palo Alto, CA) was utilized for thrombolysis and plaque ablation. Clinical success was achieved in 23/24 patients, with 23 patients (94%) surviving the acute infarction. Holmium:YAG laser is very effective and safe in thrombolysis and revascularization in this complicated clinical setting.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
The effects of cathode ray irradiation of wheat on surface moulds, respiration, flour flavour and odour, and germination

SUMMARY The effects of cathode ray radiation on the respiration, germination, flavour and odour, and microflora of stored wheat were determined by irradiating kernels at different moisture levels, under different combinations of dosage (10,600-2,000,000 rep) and of voltage (600,000–1,000,000 V.) and on one side or two sides. The lethal effects of irradiation on the natural microflora of kernels, and on the spores of Penicillium corymbiferum artificially inoculated onto kernels, were determined in preliminary experiments. Extensive studies with kernels artificially inoculated with Aspergillus repens, a proven storage mould, showed that as dosage was increased there was a corresponding reduction of viable spore load, with some reduction even at the lowest dosage of 10,600 rep. Irradiation of kernels at the highest applied voltage of 1,000,000 was more effective in killing spores than at 600,000; also a dosage applied on two sides was more effective than an equal dosage applied on one side. Spores were more readily killed when kernels were irradiated at a higher moisture level. Dosages above 42,400 rep (total dosage at 600,000 V.) significantly reduced the total number of normal plants germinating from irradiated kernels whether radiation was applied on one or both sides, or at high or low moisture levels. At 23,000 rep (total dosage at 1,000,000 V.) the number of normal plants produced from germinated kernels was significantly reduced, whether radiation was applied on one or both sides, or to kernels held at high or low moisture levels. The thresholds for irradiated flavour and odour for flour milled from irradiated kernels were about 169,600 rep (total dosage at 600,000 V.) and about 46,000 rep (total dosage at 1,000,000 V.), regardless of the moisture content or whether the dosage was applied on one or both sides. There was a significant reduction of the respiration of high moisture wheat inoculated with Aspergillus repens, when irradiated at dosages greater than 11,500 rep (total dosage at 1,000,000 V.), whether radiation was applied on one or both sides. Likewise, there was a significant reduction in respiration of kernels irradiated at dosages of 19,500 rep (total dosage at 600,000 V.), whether this was applied to one or both sides. The respiration of high moisture kernels was not reduced to that of the low moisture kernels until the 500,000 rep dosage.
Compression behaviour of woven carbon fibre-reinforced epoxy composites with moulded-in and drilled holes

Abstract A hole moulding technique, via opening the fibres in a woven carbon/epoxy composite, was used to enhance the performance of panels with circular holes. The experiments were performed on 25.4 mm wide coupons with 3.175 mm, 6.350 mm, and 9.525 mm hole diameters for moulded-in and drilled hole panels. Both types of panels showed reductions in compressive strength due to the presence of holes compared with the strength of the unnotched panel. However, the strengths of the moulded-in hole panels were always greater than those of the drilled hole ones within the experimental data range. An increase in compressive strength enhancement with increasing hole diameter was observed, and a method for the determination of the average fibre area fraction, at horizontal and vertical cross-sections adjacent to the holes, as well as a ‘strengthening index’, was introduced for the moulded-in hole panels.
Quadruply bonded dichromium complexes with bridging α-metalla-carboxylates

Abstract X-ray crystallographic studies were carried out on quadruply bonded dichromium complexes with bridging α-metalla-carboxylates to examine the influence of these ligands on the Cr4Cr bond distance. α-Metalla-carboxylic acids are the weakest carboxylic acids known to date. Cr2(μ-FpAc)4(FpAcH)2 (1) (FpAc− = (η5-C5H5Fe(CO)2(CH2COO)−) has been prepared by adjusting the pH of a solution of CrCl2 and FpAcH in water and ethanol (1:3) to about 8. 1 crystallizes in the monoclinic space group P2 1 /n ( No. 14, Z = 2) with α = 11.8349(6), b = 13.605(2), c = 17.663(2) A , β = 98.802(10)°, V = 2810.3(5) A 3 . The Cr4Cr bond distance was found to be 2.3070(8) A. FpAcH molecules are axially bound to both ends of the Cr2 unit in such a manner that the carboxylic CO group is coordinated to the Cr atom and the OH group forms a hydrogen bond to one of the equatorial O atoms of the bridging carboxylate O atoms. The axial CrO bond distance was found to be 2.246(2) A and the OO distance of the hydrogen bond was found to be 2.722(3) A, respectively.
A categorification of quantum sl(2)

Abstract We categorify Lusztig's U ˙ — a version of the quantized enveloping algebra U q ( sl 2 ) . Using a graphical calculus a 2-category U ˙ is constructed whose split Grothendieck ring is isomorphic to the algebra U ˙ . The indecomposable morphisms of this 2-category lift Lusztig's canonical basis, and the Homs between 1-morphisms are graded lifts of a semilinear form defined on U ˙ . Graded lifts of various homomorphisms and antihomomorphisms of U ˙ arise naturally in the context of our graphical calculus. For each positive integer N a representation of U ˙ is constructed using iterated flag varieties that categorifies the irreducible ( N + 1 ) -dimensional representation of U ˙ .
A simplified assay for methotrexate in biological fluids using a crude yeast lysate.

Abstract Routine pharmacokinetic monitoring of methotrexate levels in biological fluids appears to be important for clinical applications involving large doses of methotrexate with leucovorin rescue. Recently several laboratories have independently described a competitive radiobinding assay that has the necessary sensitivity, precision and simplicity for this purpose. This study describes a . modification of this assay method using a lysate of dry, active yeast as a source of binding activity. The assay is sensitive at blood concentrations of about 1 nM. No significant interference can be shown with naturally occurring folates. Specificity has also been shown by recovery experiments from serum and urine. Thus this modified assay matches the previously described radiobinding assays but with the advantage of using a methotrexate binding reagent that is readily available and quite inexpensive.
Common characteristics of new towns

Abstract All existing cities were new towns at some time in the past. Although there is a relative lack of interest in new towns in the USA today, they continue to be planned and constructed in other parts of the world. The common characteristics they exhibit constitute long-range goals for the gradual physical redevelopment of existing cities as well as shorter-range planning objectives for the superior new town.
Common anorectal disorders

Abstract Anorectal disorders are extremely common and are often manifest in the psychiatric patient population. While most conditions are self-limited, there are a variety of problems, from hemorrhoids to infection and venereal disease, that demand diagnosis and treatment. The patient is often unaware of the true nature of the problem and frequently attributes his or her symptoms to “hemorrhoids.” The distal rectum and anal canal are the location of most of the pathology discussed below. Examination consists of inspection of the perianal area, digital examination, and instrumentation with anoscopy and sigmoidoscopy. Most conditions are readily apparent. The examiner must always keep in mind that many common symptoms of anal rectal disorders such as bleeding, pain, and discharge, can be signs of malignancy. Conditions to be discussed include hemorrhoids, fissure in ano, fistulas, abscesses, pruritus ani, pilonidal sinus, condylomata acuminatum, and other venereal infections. This list includes the most common disorders with which the general physician will be confronted. Discussion will be directed toward identification and appropriate therapy.
Parameter estimation of a proton-exchange membrane fuel cell using voltage–current data

All mathematical models contain parameters that must be determined for the model to represent the behavior of the system accurately. The parameter estimation problem is usually solved as an unconstrained optimization problem independent of the model equations. However, by integrating the parameter estimation problem with the generation of the model's state profiles, constraints can be embedded directly into the optimizer, and an infeasible path solution approach can be used. Nonlinear programming is the ideal framework for formulating constrained optimization problems. The model is introduced into this framework as constraints using orthogonal collocation on finite elements. The resulting nonlinear programming problem is then solved using sequential quadratic programming. This approach is demonstrated on a mathematical model of a proton-exchange-membrane fuel cell in which four parameters are estimated and nine state profiles are determined from model generated data.
Theoretical and numerical studies of new suspended-silicon-nanowire-based static sensors

This paper reports our recent theoretical and numerical studies of new suspended-silicon-nanowire based static sensors. These static sensors detect the presence of molecules according to static deflections induced by the adsorption of molecules. As shown in Fig. 1, the static sensor consists of four suspended silicon nanowires (SiNWs) and one silicon microbeam. Each side of the microbeam includes two SiNWs, instead of one, to avoid the possible torsion of the microbeam and make the microbeam remain parallel to the substrate before detection. The microbeam is used as a platform for the adsorption of molecules. The ultra-high sensitivity of this sensor to mass loading is ensured by the extremely low bending stiffness of the four supporting SiNWs, while the position and deflection of a microbeam are easily found by a routinely used instrument due to the relatively large horizontal dimensions of the microbeam. In this work, theoretical formulation for the sensor deflections under pressure and concentration force is derived and compared with numerical results. Both theoretical and numerical results are subsequently used to optimize the design of the static sensors.
The cell cycle and transplantation of blastula nuclei in Bombina orientalis

Abstract The ability of blastula nuclei in various portions of the cell cycle to support the development of recipient eggs was examined. A non-nutritive saline medium was developed in which isolated blastula cells remained mitotically active. This medium also allowed for ready separation of daughter cells for nuclear transplantation. Donor nuclei were derived from mitotically synchronized populations of blastula cells, obtained by a manual isolation procedure. Nuclei taken from late portions of the cell cycle frequently induced a premature second-cleavage furrow, resulting in abnormal development. However, portions of the cell cycle that preclude the participation of the donor nucleus in normal development were not detected. The donor nuclei need not have initiated or completed the S phase, nor must they be “synchronized” with the recipient egg cytoplasm.
Intra-layer closed-loop control of build plan during directed energy additive manufacturing of Ti–6Al–4V

Abstract The location, timing, and arrangement of depositions paths used to build an additively manufactured component – collectively called the build plan – are known to impact local thermal history, microstructure, thermal distortion, and mechanical properties. In this work, a novel system architecture for intra-layer, closed-loop control of the build plan is introduced and demonstrated for directed-energy deposition of Ti–6Al–4V. The control strategy altered the build plan in real time to ensure that the temperature around the start point of each hatch, prior to deposition, was below a threshold temperature of 415 °C. Potential hatches with an initial temperature above this threshold were temporarily skipped. Compared with open-loop processing, closed-loop control resulted in vertical alignment of columnar prior-β grains, more uniform α-lath widths, and more-uniform microhardness values within the deposited component.
Potential attenuation of fibrinolysis by growth factors released from platelets and their pharmacologic implications.

Abstract Increased concentrations of the fast-acting tissuetype plasminogen activator (t-PA) inhibitor attenuate the fibrinolytic activity of pharmacologically administered activators of the fibrinolytic system such as t-PA. Accordingly, it was hypothesized that augmentation of synthesis and elaboration of inhibitor from the liver, leading to increased concentrations of inhibitor in plasma, or from endothelial cells in the vicinity of thrombi undergoing lysis, leading to increased concentrations locally, may contribute to failure of pharmacologically induced thrombolysis or to early reocclusion. Because platelets are rich in transforming growth factor beta and epidermal growth factor-like activity, it was thought that release of growth factors from platelets activated in vivo could mediate increases of the inhibitor in plasma by stimulating its formation in the liver and its local release from endothelial cells in the vicinity of thrombi. If so, fibrinolysis might be rendered more effective by concomitant prevention of platelet growth factor release. Transforming growth factor beta, a major constituent of platelets, increased concentrations of the t-PA inhibitor messenger ribonucleic acid (mRNA) in human hepatoma cells in a specific and dose-dependent manner. A peak effect was seen with 5 ng/ ml and a 10-fold increase in 6 hours. Release of inhibitor protein into conditioned media increased as well. Induction of the inhibitor mRNA increase was elicited by exposure as brief as 30 minutes. Cycloheximide, an inhibitor of protein synthesis, was not inhibitory. The mechanisms responsible differed from those seen with epidermal growth factor, shown previously in the laboratory to increase inhibitor mRNA. In addition, the 2 factors were synergistic. Platelet lysates elicited effects simulating those of the purified growth factors. Thus, platelet-associated growth factors released when platelets are activated in the vicinity of coronary thrombi in vivo may augment the release of t-PA inhibitor by endothelial cells (attenuating fibrinolysis locally), increase synthesis and release of inhibitor by the liver (leading to increased inhibitor in the circulation) and thereby potentiate early thrombotic reocclusion of infarct-related coronary arteries.
Szegő limit theorems

The first Szegő limit theorem has been extended by Bump–Diaconis and Tracy–Widom to limits of other minors of Toeplitz matrices. We use a more geometric method to extend their results still further. Namely, we allow more general measures and more general determinants. We also give a new extension to higher dimensions, which extends a theorem of Helson and Lowdenslager.
Decision problems in Marine fisheries

Fishery management problems are closely related to conventional types of production problems familiar to the OR analyst. In truth, the results of mathematical management models are seldom used directly to formulate policy, but the policy regimes suggested by such models have been adopted by policymakers. An example of this dynamic is the evolution of harvesting policy decisions. Approximating a problem to provide a bound on the optimal policy can suggest the appropriate policy regimes without incurring the calculational burden of an exact solution. A fleet allocation problem demonstrates this technique.
The direct dissolution of Ce2(CO3)3 and electrochemical deposition of Ce species using ionic liquid trimethyl-n-butylammonium bis(trifluoromethanesulfonyl)imide containing bis(trifluoromethanesulfonyl)imide

Abstract Ionic liquids (ILs) are solutions comprised of cation/anion pairs that are not limited by the electrochemical side reactions common to aqueous solution. The high stability of the ionic liquid provides large potential windows that can encompass the thermodynamic potentials for the reduction of f-elements such as cerium to metal. The direct dissolution of Ce2(CO3)3·xH2O into the ionic liquid trimethyl-n-butylammonium bis(trifluoromethanesulfonyl)imide [Me3NBu][TFSI] using conjugate acid bis(trifluoromethanesulfonyl)imide [HTFSI] is demonstrated. The displacement of carbonate ligand and formation of carbonic acid facilitates the in situ dissolution. The subsequent coordination of Ce with the TFSI ion in the IL is monitored using UV/vis spectroscopy and emergent ligand to metal transitions below 300 nm. Further evidence of the coordination of Ce in the ionic liquid is based on changes in the IR spectra for absorbance bands related to the sulfonyl functional groups of the TFSI anion. The reduction/oxidation of soluble Ce in IL is examined at Au, Pt, and GC (glassy carbon) electrodes. Multi-wave voltammetry at all three electrodes is consistent with the reductive deposition of Ce species from the IL solution. Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) confirm the deposition of Ce species at mica/Au electrodes.
Effect of Shipment on Pre-Incubated Fertile Eggs

Abstract INTRODUCTION IT HAS been estimated that more than a billion eggs are used for hatching purposes each year and of this number 12 million dozen, or 15 percent, are infertile. This means much needless expense in the handling and shipping of eggs which are worthless for hatching purposes. Discarding of infertile eggs at the source of supply and shipping only fertile eggs would result in a distinct advantage to both the shipper and hatcheryman. The shipper, on the one hand, could guarantee almost 100 per cent fertility and his transportation costs per fertile egg would be reduced. The hatcheryman would likewise benefit in that he could be assured of a greater number of chicks per hundred eggs set and make more efficient use of his incubator space. In view of these potential economic advantages, an experiment was undertaken to determine the feasibility of shipping pre-incubated hatching eggs and to determine . . .
The response-shock interval and conditioned suppression of avoidance in rats

Rats were trained to avoid unsignaled shocks with response-shock intervals of 30, 60, or 120 sec. When CSs of 60 sec duration paired with unavoidable shocks were then superimposed upon the avoidance baseline, responding decreased during the CS. Reductions in responding resulted in extra shocks which were potentially avoidable in all response-shock interval conditions, with the greatest increase in shocks in the response-shock 30-sec condition. Decreases in responding were greater when the CS was paired with a 2.0-mA unavoidable shock than with a 1.0-mA shock.
NMR studies of B-phase superfluid 3He at low pressures

Abstract Measurements of the temperature dependence of the B phase longitudinal NMR frequency νBL and the n texture at low pressure are presented. Near Tc, ν2BL = (0.53P (bar)+ 2.24) (1−T/Tc) × 1010Hz2to ± 5%. In a cylindrical geometry of 1 mm radius and an axial magnetic field of 284 gauss, a double peaked NMR spectrum is observed close to Tc, perhaps indicating the coexistence of two distinct n -textures. Farther below Tc, the NMR spectrum spreads out, suggesting that the n texture has become much “stiffer” at low pressure than was observed on the melting curve.
Opposing roles of δ and εPKC in cardiac ischemia and reperfusion: targeting the apoptotic machinery

Heart attacks, or acute myocardial infarctions (AMI), affect more than one million people in the US every year. The damage that occurs to the heart by AMI is often permanent and as a result, the morbidity and mortality rates of patients that experience AMIs continue to be high. Consequently, AMI patients are at significantly increased risks for future myocardial infarctions, decreased heart function, heart failure, and death [Heart and Stroke statistical update. In American Heart Association (2002) 4]. In this review, we discuss the events that lead to cardiac damage by AMI. Specifically, we discuss the current understanding of the role of ischemic damage vs. reperfusion damage, which is induced by the return of blood, oxygen, and nutrients to the organ. We also discuss the role of apoptosis and necrosis in cardiac damage, the means to protect the heart from damage by ischemia and reperfusion, and the role of protein kinase C in these processes.
Hall drag in correlated double-layer quantum Hall systems

We show that in the limit of zero temperature, double-layer quantum Hall systems exhibit a phenomenon called Hall drag, namely, a current driven in one layer induces a voltage drop in the other layer, in the direction perpendicular to the driving current. The two-by-two Hall resistivity tensor is quantized and proportional to the K matrix that describes the topological order of the quantum Hall state, even when the K matrix contains a zero eigenvalue, in which case the Hall conductivity tensor does not exist. The relation between the present work and previous ones is also discussed.
Studying X31 Influenza Membrane Binding and Fusion using Stochastic Assays and Simulations

Stochastic kinetic data of binding and fusion of X31 influenza virus to a target membrane was obtained using individual-virion imaging techniques and compared to a stochastic simulation model to assess the rate limiting steps in viral fusion. Experiments were conducted inside a microfluidic channel where total internal reflection fluorescence microscopy was used to observe individual virions interacting with a supported lipid bilayer containing sialic acid receptors. The residence time of bound viruses was measured and used to determine the binding rate constants. Following the binding studies, an acidic solution was introduced into the microfluidic device to trigger viral fusion. Fusion events were detected through the dequenching of fluorescent membrane dye. Using standard procedures to analyze the fusion kinetic data, we obtain two fit parameters denoted as k and N. One common interpretation of the fit parameters is that k represents the rate constant of the slowest step in the fusion process while N represents the number of parallel steps required to initiate fusion. N is usually greater than 1 since viral fusion requires multiple fusion proteins to act in parallel to overcome the energy barrier of membrane fusion. However, we find that N approaches values closer to 1 if a more acidic solution is used to trigger fusion, suggesting that another interpretation of N might be appropriate. We discuss these possibilities here.
Predation behaviour of land planarians

Predatory behaviour of land planarians is seldom observed or reported. Aspects reported are (1) finding prey; (2) attack behaviour; (3) capture using adhesive mucus, pharyngeal action, poisonous secretions, physical embrace; (4) feeding by extension of pharynx, releasing copious digestive fluid. The species Bipalium kewense, B. adventitium and B. pennsylvanicum attack earthworms, immobilizing them by physical holding, digesting by pharyngeal secretions and then ingesting the treated tissue. Group attacks on giant African land snails involving chemotactic tracking, occur in Platydemus manokwari and Endeavouria septemlineata. Specialized capture methods are used by some species; Rhynchodemus sylvaticus uses an expanded cephalic hood to capture small insects and in Africa, termites are captured by the elongated anterior of Microplana termitophaga as planarians wait within the colony air shaft openings to ensnare the workers in sticky mucus. The result of extensive predation by land planarians may seriously reduce the prey, e.g., providing effective population control of giant land snails by introduced Platydemus manokwari, or causing serious depletion of desirable earthworm populations by the exotic Artioposthia triangulata in North Ireland.
Sibling Relationships in Old Age: A Typology

Sibling interactions in old age have received limited attention in social science literature. This article examines the different kinds of relationships which exist between siblings in old age and the ways in which each type meets or ignores the social and psychological needs of older people. Five types of sibling relationships emerged from data collected in open-ended, exploratory interviews with thirty men and thirty women over the age of sixty-five who had at least one living sibling. Each type reflects a discrete pattern of instrumental support, emotional support, and contact, as well as a different degree of closeness, envy, resentment, approval, and involvement with the sibling. The distribution of same-sex and cross-sex dyads among the types suggests gender differences in sibling interactions based on the gender composition of the sibling dyad rather than on the gender of the respondent.
Synthesis and antifungal activities of miltefosine analogs

Miltefosine is an alkylphosphocholine that shows broad-spectrum in vitro antifungal activities and limited in vivo efficacy in mouse models of cryptococcosis. To further explore the potential of this class of compounds for the treatment of systemic mycoses, nine analogs (3a-3i) were synthesized by modifying the choline structural moiety and the alkyl chain length of miltefosine. In vitro testing of these compounds against the opportunistic fungal pathogens Candida albicans, Candida glabrata, Candida krusei, Aspergillus fumigatus, and Cryptococcus neoformans revealed that N-benzyl-N,N-dimethyl-2-{[(hexadecyloxy)hydroxyphosphinyl]oxy}ethanaminium inner salt (3a), N,N-dimethyl-N-(4-nitrobenzyl)-2-{[(hexadecyloxy)hydroxyphosphinyl]oxy}ethanaminium inner salt (3d), and N-(4-methoxybenzyl)-N,N-dimethyl-2-{[(hexadecyloxy)hydroxyphosphinyl]oxy}ethanaminium inner salt (3e) exhibited minimum inhibitory concentrations (MIC) of 2.5-5.0 μg/mL against all tested pathogens, when compared to miltefosine with MICs of 2.5-3.3 μg/mL. Compound 3a showed low in vitro cytotoxicity against three mammalian cell lines similar to miltefosine. In vivo testing of 3a and miltefosine against C. albicans in a mouse model of systemic infection did not demonstrate efficacy. The results of this study indicate that further investigation will be required to determine the potential usefulness of the alkylphosphocholines in the treatment of invasive fungal infections.
Dkk4 and Eda Regulate Distinctive Developmental Mechanisms for Subtypes of Mouse Hair

The mouse hair coat comprises protective “primary” and thermo-regulatory “secondary” hairs. Primary hair formation is ectodysplasin (Eda) dependent, but it has been puzzling that Tabby (Eda-/y) mice still make secondary hair. We report that Dickkopf 4 (Dkk4), a Wnt antagonist, affects an auxiliary pathway for Eda-independent development of secondary hair. A Dkk4 transgene in wild-type mice had no effect on primary hair, but secondary hairs were severely malformed. Dkk4 action on secondary hair was further demonstrated when the transgene was introduced into Tabby mice: the usual secondary follicle induction was completely blocked. The Dkk4-regulated secondary hair pathway, like the Eda-dependent primary hair pathway, is further mediated by selective activation of Shh. The results thus reveal two complex molecular pathways that distinctly regulate subtype-based morphogenesis of hair follicles, and provide a resolution for the longstanding puzzle of hair formation in Tabby mice lacking Eda.
Odd symplectic groups.

On definit des groupes symplectiques sur des espaces vectoriels de dimension impaire. Ces groupes de Lie ne sont ni simples ni reductifs. On obtient une formule de caracteres pour certaines representations tensorielles de ces groupes
Investment in a small antique

Investors in times of inflation seek to hedge their investments against inflationary loss. High inflation over many years helps account for a considerable growth in the market for small and cheap antiques such as depression glass, beer cans and baseball cards. This interest has been accompanied by a movement of the auction houses into the market to hold auctions for items that previously were unprofitable. As a low value antique, the first auction for the lead toy soldier, held by a major house, Phillips, occurred in December 1978. Auctions have since been held quarterly with the number of auctioned items increasing quite markedly, particularly after Christie's entrance in the market in June 1981.