cssi/SciSciGPT-SciSciNet huggingface dataset:
The interaction of some carcinogens with rat liver RNA.

Abstract The sedimentation rates of rat liver high molecular weight RNA are much smaller in 0.30 M KCl than in 0.14 M NaCl. A further decrease is observed if one of several carcinogens is added to the 0.30 M KCl solution. The observed distribution of sedimentation coefficients depended on the particular isomer of fluorenamine or carbamate added to the 0.30 M KCl solution. There was no correlation between the ultracentrifugal results and the carcinogenicity of the compounds. The decrease in sedimentation rates observed in 0.30 M KCl and 0.30 M KCl + 0.04 urethane could be reversed by increasing the KCl concentration. The size of the RNA subunit was determined by equilibrium sedimentation and found to be 80,000–120,000.
Development of high-gradient and open-gradient magnet separation of dry fine coal

High gradient magnetic separation of pyritic sulfur and ash forming minerals from dry, fine coal has been developed on a laboratory scale and demonstrated at commercial scale. Similarly, open gradient magnetic separation of dry, fine coal has been demonstrated on a laboratory scale and extrapolated to 300 kg per hour in a solenoidal configuration magnet. A modeling technique has been developed to analyze magnet design, separating forces, and particle trajectories, and has been experimentally verified. Practical magnet designs have been shown which can exert separating forces several times those in existing magnets and in large processing volumes.
Towards a unified framework for pre-silicon validation

One of the major problems seen in the pre-silicon validation realm today is the lack of a unified framework for all pre-silicon validation efforts including security validation. Lack of a unified framework for pre-silicon validation presents a “communication” challenge among different validation tool teams. While each team maintains and enhances a particular tool depending on the project they support and while these projects shift geographies to keep up with the product development life cycle, keeping the tools up to date, addressing specific tool changes and communicating the tool changes among project teams and dependent tool teams is emaciating. With this perspective, this paper seeks to highlight this issue and present a high-level solution space to address this problem. Further, the paper highlights outstanding issues that need to be resolved to enable such a unified pre-silicon validation framework to be successful.
Lobectomy in Octogenarians With Non-Small Cell Lung Cancer: Ramifications of Increasing Life Expectancy and the Benefits of Minimally Invasive Surgery

Background As the population ages, clinicians are increasingly confronted with octogenarians with resectable non-small cell lung cancer (NSCLC). We reviewed the outcomes of octogenarians who underwent lobectomy for NSCLC by video-assisted thoracic surgery (VATS) versus open thoracotomy, to determine if there was a benefit to the VATS approach in this group. Methods We conducted a retrospective single-institution review of patients age 80 years or greater who underwent a lobectomy for NSCLC from 1998 to 2009. Outcomes including complication rates, length of stay, disposition, and long-term survival were analyzed. Results One hundred twenty-one octogenarians underwent lobectomy: 40 VATS and 81 through open thoracotomy. Compared with thoracotomy, VATS patients had fewer complications (35.0% vs 63.0%, p = 0.004), shorter length of stay (5 vs 6 days, p = 0.001), and were less likely to require admission to the intensive care unit (2.5% vs 14.8%, p = 0.038) or rehabilitation after discharge (5% vs 22.5%, p = 0.015). In multivariate analysis, VATS was an independent predictor of reduced complications (odds ratio, 0.35; 95% confidence interval, 0.15 to 0.84; p = 0.019). Survival comparisons demonstrated no significant difference between the two techniques, either in univariate analysis of stage I patients (5-year VATS, 76.0%; thoracotomy, 65.3%; p = 0.111) or multivariate analysis of the entire cohort (adjusted hazard ratio, 0.59; 95% confidence interval, 0.27 to 1.28; p = 0.183). Conclusions Octogenarians with NSCLC can undergo resection with low mortality and survival among stage I patients, which is comparable with the general lung cancer population. The VATS approach to resection reduces morbidity in this age demographic, resulting in shorter, less intensive hospitalization, and less frequent need for postoperative rehabilitation.
Modeling Ophthalmic Drug Delivery by Soaked Contact Lenses

Approximately 90% of all ophthalmic drug formulations are now applied as eye drops. While eye drops are convenient and well-accepted by patients, ∼95% of the drug contained in the drops is lost due to absorption through the conjunctiva or through the tear drainage. Ophthalmic drug delivery via contact lenses is more effective because it increases the residence time of the drug in the eye and leads to a larger fractional intake of drug by the cornea. In this paper, we model the drug release from the contact lens into the pre- and postlens tear films and the subsequent uptake by the cornea. The motion of the contact lens, which is driven by the eyelid motion during a blink, enhances the mass transfer in the postlens tear film (POLTF). We use regular perturbation methods to obtain the Taylor dispersion coefficient for mass transfer in the POLTF. The diffusion of drug in the gel is assumed to obey Fick's law, and the diffusion in the gel and the mass transfer in the POLTF are combined to yield an integro-diff...
Fractionation Trends Among IVA Iron Meteorites: Contrasts with IIIAB Trends

A neutron-activation study of 49 group-IVA irons shows much lower negative slopes on Ir-Au and Ir-As diagrams than observed in the larger magmatic group IIIAB. This difference seems to reflect the tendency of D(sub Ir), D(sub Au), and D(sub As) to increase with increasing S content. Contents of S and other volatiles are much lower in IVA irons than IIIAB irons. We show that both groups can be fit with Dx values that depend quadratically on S, with initial IVA S contents about 6X lower than those in IIIAB. The IVA scatter fields show a spread in Au or As at constant Ir that appears to reflect variations in the fraction of trapped melt between 0% and 30%. Copper shows an S-shaped trend that may reflect moderate positive and negative changes in D(sub Cu) as the magma evolved or, less likely, sampling variations in a broad band reflecting fractionation and trapping of melt. Gibeon, the largest IVA iron with a mass greater than 30 tons, shows an appreciable range in compositions consistent either with differences in the degree of magma crystallization or with differences in the content of trapped melt. A striking difference between IVA and IIIAB is observed in the Ir/Au ratios in the most Ir-rich irons in the groups; that in IVA is 40% lower than the IIIAB ratio, and lower than those in other iron-meteorite groups, The IVA Ir/Au ratio is about half the ratios in the chondrite groups. We examined three possible explanations of this anomaly: (1) the high-Ir irons contain large amounts of trapped melt: or (2) half of the IVA core (i.e., the first 50% to crystallize) is missing from the terrestrial set of IVA irons; or (3) the IVA magma formed by incomplete melting of the metal in the chondritic precursor material, with the metal that remained in the mantle having high Ir and low Au contents. Plausibility arguments favor the third possibility. The third scenario is the most plausible, but the second cannot be ruled out. We review recent evidence regarding the cooling rates in group IVA. In contrast to recent interpretations, we note several lines of evidence that indicate constant cooling rates independent of composition, as expected if all IVA meteorites were in the same core when cooling between 900 and 650 K occurred.
Is neurally mediated hypotension an unrecognised cause of chronic fatigue

Neurally mediated hypotension is now recognised as a common cause of otherwise unexplained recurrent syncope, but has not been reported in association with chronic fatigue. We describe seven consecutive non-syncopal adolescents with chronic post-exertional fatigue, four of whom satisfied strict criteria for chronic fatigue syndrome. Upright tilt-table testing induced significant hypotension in all seven (median systolic blood pressure 65 mm Hg, range 37-75), consistent with the physiology of neurally mediated hypotension. Four had prompt improvement in their chronic fatigue when treated with atenolol or disopyramide. These observations suggest an overlap in the symptoms of chronic fatigue syndrome and neurally mediated hypotension.
Play & playwork: 101 stories of children playing

As the title implies, play is the dominant theme of this book. Brown has done a masterful job weaving theories, observations, research, and implications to produce a broad picture of how and why ch...
Malignant histiocytic lymphoma (reticulum cell sarcoma) in pregnancy

Abstract Malignant histiocytic lymphoma has been rarely found during pregnancy. The present case appears to be the eleventh reported in the world literature. Its management represented a diagnostic challenge because of the unusual symptoms. Surgery, external irradiation, and chemotherapy produced excellent and lasting results with complete recovery of the mother and an unaffected offspring.
Study of non-linear penalties in metropolitan DWDM transmission systems that employ directly modulated DFB laser transmitters

Experimentally verified simulations show that four-wave mixing (FWM) and cross-phase modulation (XPM) in optical fibers do not produce significant non-linear impairments when chirped waveforms, derived from directly modulated laser transmitters, propagate through DWDM metropolitan systems. The result is explained through reduced interferometric noise at the bandwidth-limited receiver due to beating between the spectrally broad signal and corresponding FWM tones. Introduction of a novel low bit-rate probe simulation technique to separate noise from distortion in a bit sequence uncovers XPM (FWM) as the main non-linear degradation in systems running at 10 (2.5) Gb/s with tight channel spacings and relatively high input powers.
Proof validation in real analysis: Inferring and checking warrants

Abstract In the study reported here, we investigate the skills needed to validate a proof in real analysis, i.e., to determine whether a proof is valid. We first argue that when one is validating a proof, it is not sufficient to make certain that each statement in the argument is true. One must also check that there is good reason to believe that each statement follows from the preceding statements or from other accepted knowledge, i.e., that there is a valid warrant for making that statement in the context of this argument. We then report an exploratory study in which we investigated the behavior of 13 undergraduates when they were asked to determine whether or not a particular flawed mathematical argument is a valid mathematical proof. The last line of this purported proof was true, but did not follow legitimately from the earlier assertions in the proof. Our findings were that only six of these undergraduates recognized that this argument was invalid and only two did so for legitimate mathematical reasons. On a more positive note, when asked to consider whether the last line of the proof followed from previous assertions, a total of 10 students concluded that the statement did not and rejected the proof as invalid.
A methodological assessment of the use of key informants

Abstract The key informant technique is assessed in terms of the ability of different types of informants to report on various aspects of the social system in which they perform role functions. Role theory suggests that informants occupying a specialized role within a social structure provide greater information on role-related aspects of the structure than informants occupying positions unrelated to the area being investigated. Empirical evidence in support of this assertion is presented.
Space-Time Code. II

Quantum concepts can be applied to space-time processes to make a quantum (q) theory that is free of the possibility of divergencies inherent in classical continuum theories, yet causal, Lorentz-invariant, and asymptotically Poincar\'e-invariant for large times. A general technique, algebraic quantization, is provided for going from classical (c) paradigms, typically discrete logical structures, to q analogs. Applied to the two-dimensional c checker-board, algebraic quantization gives a q theory of time and space asymptotic to the four-dimensional Minkowski c theory in the limit of large time. Applied to the simplest dynamics on such a checkerboard, a piece that makes the same move again and again, algebraic quantization gives a q dynamics asymptotic to a massless spin-\textonehalf{} two-component dynamics in the same limit. The quantum of time, if it exists, must have spin \textonehalf{}. Some features of general relativity such as curvature seem plausible consequences of a quantum theory of space-time processes.
Improving faculty feedback to resident trainees during a simulated case: a randomized, controlled trial of an educational intervention.

Background Although feedback conversations are an essential component of learning, three challenges make them difficult: the fear that direct task feedback will harm the relationship with the learner, overcoming faculty cognitive biases that interfere with their eliciting the frames that drive trainees' performances, and time pressure. Decades of research on developmental conversations suggest solutions to these challenges: hold generous inferences about learners, subject one's own thinking to test by making it public, and inquire directly about learners' cognitive frames. Methods The authors conducted a randomized, controlled trial to determine whether a 1-h educational intervention for anesthesia faculty improved feedback quality in a simulated case. The primary outcome was an analysis of the feedback conversation between faculty and a simulated resident (actor) by using averages of six elements of a Behaviorally Anchored Rating Scale and an objective structured assessment of feedback. Seventy-one Harvard faculty anesthesiologists from five academic hospitals participated. Results The intervention group scored higher when averaging all ratings. Scores for individual elements showed that the intervention group performed better in maintaining a psychologically safe environment (4.3 ± 1.21 vs. 3.8 ± 1.16; P = 0.001), identifying and exploring performance gaps (4.1 ± 1.38 vs. 3.7 ± 1.34; P = 0.048), and they more frequently emphasized the professionalism error of failing to call for help over the clinical topic of anaphylaxis (66 vs. 41%; P = 0.008). Conclusions Quality of faculty feedback to a simulated resident was improved in the interventional group in a number of areas after a 1-h educational intervention, and this short intervention allowed a group of faculty to overcome enough discomfort in addressing a professionalism lapse to discuss it directly.
The development and evaluation of a computer-administered measure of cognitive complexity

Abstract The present study presents and evaluates the Computer-Administered Rep Test (CART). The CART is a micro computer program that automates both the administration and scoring of a repertory grid based measure of cognitive complexity. Preliminary evaluation of the CART indicates that it provides a useful alternative to traditional paper-and-pencil administered repertory grid measures of cognitive complexity. We also examine the effect of an alternative scoring approach on the reliability of scores derived from role repertory grid measures of cognitive complexity. Results indicate that this scoring approach substantially enhances the reliability of cognitive complexity scores derived from both the paper-and-pencil and computer-administered measures.
The absolute-value estimate for symmetric multilinear forms☆

Abstract Let T ( v 1 , …, v n ) be a symmetric multilinear function on vectors v 1 , …, v n in some R r . Let M = max ‖ v ‖=1 | T ( v , …, v )|. Then | T ( v 1 , …, v n )| ⩽ ‖ v 1 ‖⋯‖ v n ‖ M . Equality (for nonzero v i ) can occur only in very special cases when the v i are not all parallel, and never if they span more than a plane. The inequality is known, but the proof here is new, as are the precise conditions for equality.
Crystallization theory relating to urinary stone formation

Although little is known at the present time about the factors which control the nucleation of pathological concretions, the growth of such solid phases in biological fluids such as urines must be mediated by physical chemical principles governing the kinetics of crystallization. Elucidation of the mechanism of the precipitation processes may be complicated by the difficulty in defining the degree of supersaturation in these biological systems but a great deal can be learned from in vitro crystal growth kinetic studies. In this paper, the physical chemical principles which govern the nucleation and growth of sparingly soluble salts in aqueous media are discussed as they relate to urinary stone formation. In vivo, the number of mineral phases which is involved is relatively small and the results for two important salt systems, the calcium phosphates and calcium oxalates are discussed in the light of recent kinetics studies in which the supersaturation is maintained constant during crystallization experiments.
HFC 43-10 mee

Abstract F -Pentene-2 is obtained in 85–90% yield from a highly selective condensation of hexafluoropropene with tetrafluoroethene using aluminum halide catalysis. Vapor phase reduction affords 2H,3H- F -pentane (HFC 43-10 mee) in 99% yield, while liquid phase reduction using polar media produces the related trihydropentanes. Conditions and by-products of these new processes will be discussed as well as characteristics of the new liquid HFC compositions now available.
Silica nanoparticle antireflective coating with PVP adhesion layer

In this work, a transparent polymer, polyvinylpyrrolidone (PVP), is used as an adhesion layer for silica nanoparticle antireflective glass coatings. PVP was found to significantly increase the uniformity of the deposited silica nanoparticle film and results in an average transmittance of greater than 98% in the wavelength range of 450-1100 nm. Silica nanoparticle coatings deposited without the PVP layer resulted in an average transmittance of 95%. When the PVP/SiO2 coated glass was used to package a crystalline silicon solar cell, the short circuit current was increased to 14.97 mA/cm2 from 13.90 mA/cm2 for the same cell packaged with bare glass.
In situ photogelation kinetics of Laponite nanoparticle-based photorheological dispersions

In situ photorheology experiments were conducted to investigate the kinetics of UV-triggered photogelation of aqueous Laponite nanoparticle dispersions formulated with less than 10 wt% of a triblock copolymer (Pluronic F127) and diphenyliodonium-2-carboxylate monohydrate, a photoacid generator (PAG). We show that gelation kinetics depend strongly on solution composition and intensity of UV light used during in situ photorheology experiments. A decrease in gelation rate was observed with increasing Pluronic F127 concentrations while higher PAG and Laponite concentrations result in higher gelation rates. Changing the intensity of UV light from 100 mW cm−2 to 150 mW cm−2 at a constant composition reduced the exposure time required prior to onset of gelation by half. Finally, the effect of Laponite and PAG on the micellization of F127 was probed using differential scanning calorimetry (DSC). The results show that the presence of Laponite particles and PAG suppresses the enthalpic endotherm associated with micelle formation in solutions containing up to 7.2 wt% Pluronic F127. Using these results, we present a detailed mechanism for the photogelation phenomenon as well as the parameters surrounding intelligent design and formulation of these systems.
Robust omniphobic surfaces

Superhydrophobic surfaces display water contact angles greater than 150° in conjunction with low contact angle hysteresis. Microscopic pockets of air trapped beneath the water droplets placed on these surfaces lead to a composite solid-liquid-air interface in thermodynamic equilibrium. Previous experimental and theoretical studies suggest that it may not be possible to form similar fully-equilibrated, composite interfaces with drops of liquids, such as alkanes or alcohols, that possess significantly lower surface tension than water (γlv = 72.1 mN/m). In this work we develop surfaces possessing re-entrant texture that can support strongly metastable composite solid-liquid-air interfaces, even with very low surface tension liquids such as pentane (γlv = 15.7 mN/m). Furthermore, we propose four design parameters that predict the measured contact angles for a liquid droplet on a textured surface, as well as the robustness of the composite interface, based on the properties of the solid surface and the contacting liquid. These design parameters allow us to produce two different families of re-entrant surfaces— randomly-deposited electrospun fiber mats and precisely fabricated microhoodoo surfaces—that can each support a robust composite interface with essentially any liquid. These omniphobic surfaces display contact angles greater than 150° and low contact angle hysteresis with both polar and nonpolar liquids possessing a wide range of surface tensions.
Seizures in pregnancy.

Dr. Prudence Kline: A previously healthy 37-year-old right-handed woman (G3 P2 012) presented to the George Washington University Medical Center Emergency Department complaining of a severe headache ten days after a natural term vaginal delivery of a healthy infant. One day after delivering she was told that her blood pressure was elevated, but she was not treated and the pressure normalized. Four days after delivering (while still in the hospital) her temperature rose to 38.3”C, and she experienced a shaking chill and developed the gradual onset of an intense, pounding, bitemporal headache. Five days after delivering, the fever abated, the headache improved, and she was discharged from the hospital. On the following day, the headache recurred, and for the next four days she experienced a severe headache refractory to barbiturates and narcotic analgesics. She also indicated having nasal stuffiness during this period. Eventually, she presented to the emergency department seeking relief from the pain. On physical examination, the patient appeared to be in severe distress from pain. Her blood pressure was 140/90, pulse was 90 per minute, temperature was 37°C orally, and respiratory rate was 16 per minute. Results of her general physical examination were otherwise unremarkable except for trace ankle edema. On neurological examination, she was alert and oriented, with normal cognitive function. Her strength was 515 throughout, and light touch, vibratory, position sense, and two-point discrimination were normal. There was no tremor or drift. Cerebellar function was normal. Reflexes were 3 + in the upper extremities and 2 + in the lower extremities, and no pathological reflexes were noted. A neurology consultant examined the patient and expressed the opinion that the headache was “benign.” Before discharge from the emergency department the patient complained of loss of vision, and approximately 30 seconds later
An experimental comparison of human schedulers and heuristic algorithms for the traveling salesman problem

Abstract Vehicle routing and scheduling for laundry, courier, mail, and other service operations is a significant service industry problem. Several computer-based heuristic algorithms have been developed to assist schedulers in developing efficient delivery (and pick up) vehicle routes. This paper reports the results of an experiment that compared the performance of inexperienced human schedulers and seven heuristic vehicle routing algorithms. A large set of traveling salesman test problems ranging in size from 10 to 80 customers was used in the experiment. The results of the experiment suggest that inexperienced, untrained human schedulers can consistently find traveling salesman solutions as good as or better than all but one of the seven heuristic algorithms tested (including the widely used ClarkeWright distance saved heuristic and the recently published largest-angle insertion heuristic). The human schedulers found traveling salesman routes as good as the best heuristic tested (Lin 's 3-optimal) in 29 percent of the test problems. On average, the human schedulers' solution distances were only 2.8 percent above the 3-optimal heuristic solution distances.
Myocardin: A Component of a Molecular Switch for Smooth Muscle Differentiation

A hallmark of smooth muscle cells (SMCs) in culture and the injured vessel wall is their phenotypic modulation from a differentiated state to one of heightened growth, migration, and matrix synthesis. The transcriptional mechanisms underlying this altered genetic program have yet to be elucidated. Serum response factor (SRF) has emerged as a critical regulator of SMC-restricted gene expression via its interaction with proximal CArG elements; however, levels of SRF protein do not change during SMC phenotypic modulation, suggesting a role for other factors or events in this process. One such factor could be myocardin, a novel SRF coactivator recently cloned from cardiac tissue. Levels of myocardin are abundantly expressed in rat aortic media along with key SMC-restricted genes. In several SMC lines, myocardin mRNA levels decrease in parallel with the loss or attenuation of SMC marker expression. Transient transfection experiments with CMV-driven myocardin in both SMC and non-SMC reveal CArG-dependent transactivation of the SM-Calp promoter-enhancer. Several additional CArG-dependent SMC promoters show variable activation in a cell-and promoter-context dependent manner. To determine whether myocardin could activate an endogenous program of SMC differentiation, we stably transfected L6 myoblasts and assessed SMC marker expression and growth. Results reveal the expression of several SMC markers concomitant with a lower growth potential. Collectively, these studies suggest that myocardin is an important component of a molecular switch for the SMC differentiation program.
Non-Unanimous Power Inter-Cell Interference Coordination in Heterogeneous Networks

Heterogeneous Networks (HetNet), particularly Femto cells, were introduced to meet the exigent need for higher network capacity. Although Femto cells increased the network capacity, they increased the interference to the Macro Indoor users.In order to avoid the high decrease in cell edge throughput different interference mitigation techniques were introduced like Inter-Cell Interference Coordination and Power Control techniques. In this paper, Non- Unanimous Power Inter-cell Interference Coordination (NUP-ICIC), and Non Unanimous Power Control with Constraint (NUP-C) algorithms are proposed . The schemes can achieve high spectral efficiency with an increase the cell-edge and with high power efficiency.
Characterization of Liver Enlargement Induced by Compound LY171883 in Rats

Abstract Compound LY 171883 caused dose-related and reversible hepatomegaly in male Fischer 344 rats. Histological examination revealed hepatocellular hypertrophy with no other evidence of liver disease. There were only minor changes in serum glucose, total bilirubin, alkaline phosphatase, and alanine transaminase which were generally unrelated to dose and dissociable from the hepatomegaly. Total liver DNA increased but the DNA concentration decreased, indicating that liver growth involved a combination of hypertrophy and hyperplasia. Total liver protein and RNA increased. Hepatic mitochondrial protein content increased but cytochrome oxidase activity was not changed. There were minor changes in mitochondrial respiratory parameters; however, all the values were in the normal range and there was no indication of mitochondrial toxicity. Microsomal protein, drug-metabolizing activity, and cytochrome P -450 increased, but glucose-6-phosphatase activity was not changed. The induction of drug-metabolizing enzymes and absence of toxicity were evidence that the hepatomegaly was an adaptation to an increased functional load in the liver. An increase in catalase activity suggested that the response may have also involved peroxisomes. In addition to rats, LY171883 administration caused hepatomegaly in mice and hamsters at daily exposures exceeding 100 mg/kg. The response was not observed in guinea pigs, beagle dogs, or rhesus monkeys given maximum tolerated doses, indicating LY171883-induced hepatomegaly is not a response common to all species. The doses required to elicit hepatomegaly greatly exceeded doses that produce pharmacological efficacy in animals and those that are expected to be used clinically. Since humans will not receive doses comparable to those given rodents, and considering that the primate species tested did not experience hepatomegaly, it is unlikely that the effect observed in rodents can be extrapolated to humans.
On the dearth of philosophical contributions to medicine.

A recent editorial in this journal calls for more philosophical work in the areas of philosophy of medical science and research methodology [1]. The purpose of the present paper is to bring to light and discuss some obstacles and opportunities for development in these areas. In section I, barriers to increased philosophical work in medicine outside ethics are discussed. In sections II and III, additional areas in medicine ripe for philosophical work are identified and discussed: (a) improving the epistemic fitness of much current clinical reasoning, (b) defining the conditions under which greater epistemic fitness can be achieved, and (c) technology assessment.
The Status of the Race Concept in Physical Anthropology

There are hereditary differences among human beings. Some of these differences have geographical correlates. Some genetic variants that produce physical or behavioral deficits occur significantly more often in some areas, or in some ethnic groups, than in others. However, none of these facts provides any intellectual support for the race concept, for racial classifications, or for social hierarchies based on ethnic-group membership. The geographical element of the race concept is important in theory but is widely ignored in practice since it does not conform well to the facts of current human phenotype distribution. Much of the literature on supposed racial differences involves such geographically meaningless exercises as studying differences among "races" by subdividing a sample of North Americans. If races are defined as geographically delimited conspecific populations characterized by distinctive regional phenotypes, then human races do not exist now and have not existed for centuries,
Synthesis and Separation Performance of SSZ-13 Zeolite Membranes on Tubular Supports

SSZ-13 zeolite membranes were synthesized on the inside surface of porous stainless steel tubes. In parallel with zeolite pores, the membranes had nonzeolite pores that were larger than the 0.38-nm...
Comparison of Roasted Tobacco Volatiles with Tobacco Essential Oil and Cigarette Smoke Condensate

The composition of roasted tobacco volatiles was compared with those of tobacco essential oil and cigarette smoke condensate. Tobacco essential oil gave a refreshing, sweet aroma in addition to a tobacco-like aroma. These aromas might be attributable to terpenoid compounds. Phenols in cigarette smoke condensate were much higher than those in roasted tobacco volatiles. By column chromatography of the roasted tobacco volatiles, components with burnt sugar-like aromas such as 2-hydroxy-3-methyl-2-cyclopentenone, 3-hydroxy-2-methylpyran-4-one, and 4-hydroxy-2,5-di-methyl-3(2H)-furanone were identified, and these are assumed to play an important role in the development of the aroma of roasted tobacco volatiles. Although the cigarette smoke condensate contained components with a burnt sugar-like aroma such as 2-hydroxy-3-methyl-2-eyclopen-tenone in much higher concentrations than roasted tobacco volatiles, their aroma was suppressed by coexistent components, probably volatile N-basic substances.
Contribution of his bundle recordings to the understanding of clinical arrhythmias

Abstract His bundle electrocardiography has enhanced our knowledge of cardiac electrophysiology. The catheter technique for recording potentials from the specialized conducting tissues is most useful in determining the site (or sites) of atrioventricular and ventriculoatrial delays and blocks. Various types of ventricular preexcitation resulting from conduction through Kent, Mahaim and James bundles are adequately identified with this method. In some cases it provides the only means of differentiation between supraventricular and ventricular arrhythmias. A secondary gain obtained from His bundle recordings is the evaluation of the electrophysiologic effects of various drugs. Information thus obtained is not only academically important but also clinically useful, since it is a significant factor in establishing the proper therapy.
Tying, Banking, and Antitrust: It's Time for a Change

The anti-tying section (Sec. 106) of the Bank Holding Company Act of 1970 severely limits U.S. banks' or bank holding companies' ability to link one product or service to another. Though the provisions of Sec. 106 resemble the anti-tying provisions of the U.S. antitrust laws, the latter are considerably less restrictive and more flexible. Sec. 106 represents a misguided legislative effort to deal with a perceived problem of banks' market power. Though tying can be a manifestation of market power, it is more likely—especially for banking—to represent efficient combinations of complementary components. Regulatory and judicial enforcement of Sec. 106 surely has seriously inhibited the flexibility and efficiency of bank pricing and product offerings. A simple solution to this legislative over-regulation is to repeal Sec. 106 and instead extend the reach of the antitrust laws to cover abusive tying by banks.
An Optimal Control Approach to Sensorimotor Parametrization

We tested the hypothesis that human sensorimotor response can be modelled as a linear quadratic gaussian (LQG) controller (a Bayesian optimal state estimator in series with a linear quadratic regulator), thereby inferring parameters characterizing human sensorimotor response in a simple experimental context. Subjects used a modified computer mouse to attempt to keep a displayed cursor at a fixed desired location despite a gaussian random disturbance and simple cursor dynamics. Data were fit to an LQG model whose assumptions are simple and generally consistent with other sensorimotor work, greatly reducing the dimensionality of time series data in a way that preserved the dynamic qualities of the system while yielding a small number of parameters. The parameters lend themselves to physical interpretation: noise intensity, control cost weighting, and delay. Inferred control cost and motor noise intensity showed statistically significant variation across subjects. The quality of the fit and of the inferred parameters generally support the hypothesis.
Nickel Induces a Signature Mutation for Oxygen Free Radical Damage

Abstract We have determined the specificity of mutations produced by nickel(II), a known human carcinogen, in a forward mutation assay and also used a sensitive reversion assay to show that Ni(II), like iron and copper, can produce tandem double CC→TT mutations, a hallmark of damage to DNA by either UV irradiation or oxygen free radicals. A reduction in mutation frequencies by the addition of oxygen radical scavengers also supports the involvement of reactive oxygen species in DNA damage and mutagenesis by Ni(II). Mutagenesis by Ni(II) is enhanced by the addition of both hydrogen peroxide and a tripeptide glycyl-glycyl-l-histidine. The enhancement of mutagenesis of Ni(II) by the tripeptide indicates that these complexes could serve to localize Ni(II) in nuclei and mediate DNA damage and mutagenesis via the generation of short-lived oxygen free radicals. These data suggest that Ni(II) carcinogenesis may proceed via the generation of active oxygen species and furthermore provide a model for nickel carcinogenesis based on the binding of Ni(II) to nuclear proteins.
Computation of Image Spatial Entropy Using Quadrilateral Markov Random Field

Shannon entropy is a powerful tool in image analysis, but its reliable computation from image data faces an inherent dimensionality problem that calls for a low-dimensional and closed form model for the pixel value distributions. The most promising such models are Markovian, however, the conventional Markov random field is hampered by noncausality and its causal versions are also not free of difficulties. For example, the Markov mesh random field has its own limitations due to the strong diagonal dependency in its local neighboring system. A new model, named quadrilateral Markov random field (QMRF) is introduced in this paper in order to overcome these limitations. A property of QMRF with neighboring size of 2 is then used to decompose an image prior into a product of 2-D joint pdfs in which they are estimated using a joint histogram under the homogeneity assumption. In addition, the paper includes an extension of the introduced method to the computation of image spatial mutual information. Comparisons on synthesized images as well as two applications with real images are presented to motivate the developments in this paper and demonstrate the advantages in the performance of the introduced method over the existing ones.
Collective motion from consensus with Cartesian coordinate coupling - Part I: Single-integrator kinematics

This is the first part of a two-part paper on collective motion from consensus with Cartesian coordinate coupling. Collective motions including rendezvous, circular patterns, and logarithmic spiral patterns can be achieved by introducing Cartesian coordinate coupling to existing consensus algorithms. In this first part, we study the collective motions of a team of vehicles in 3D by introducing a rotation matrix to an existing consensus algorithm for single-integrator kinematics. It is shown that both the network topology and the value of the Euler angle affect the resulting collective motions. We show that when the nonsymmetric Laplacian matrix has certain properties and the Euler angle is below, equal, or above a critical value, the vehicles will eventually rendezvous, move on circular orbits, or follow logarithmic spiral curves. In particular, when the vehicles eventually move on circular orbits, the relative radius of the orbits (respectively, the relative phase of the vehicles on their orbits) is equal to the relative magnitude (respectively, the relative phase) of the components of a right eigenvector associated with a critical eigenvalue of the nonsymmetric Laplacian matrix. Simulation results are presented to demonstrate the theoretical results.
Disulfide Bonds and Membrane Topology of the Vaccinia Virus A17L Envelope Protein

The envelope protein encoded by the vaccinia virus A17L open reading frame is essential for virion assembly. Our mutagenesis studies indicated that cysteines 101 and 121 form an intramolecular disulfide bond and that cysteine 178 forms an intermolecular disulfide linking two A17L molecules. This arrangement of disulfide bonds has important implications for the topology of the A17L protein and supports a two-transmembrane model in which cysteines 101 and 121 are intraluminal and cysteine 178 is cytoplasmic. The structure of the A17L protein, however, was not dependent on these disulfide bonds, as a recombinant vaccinia virus with all three cysteine codons mutated to serines retained infectivity.
Advanced liver fibrosis: diagnosis with 3D whole-liver perfusion MR imaging--initial experience.

Institutional review board approval and informed consent were obtained for this HIPAA–compliant study. The purpose of this study was to prospectively evaluate sensitivity and specificity of various estimated perfusion parameters at three-dimensional (3D) perfusion magnetic resonance (MR) imaging of the liver in the diagnosis of advanced liver fibrosis (stage ≥ 3), with histologic analysis, liver function tests, or MR imaging as the reference standard. Whole-liver 3D perfusion MR imaging was performed in 27 patients (17 men, 10 women; mean age, 55 years) after dynamic injection of 8–10 mL of gadopentetate dimeglumine. The following estimated perfusion parameters were measured with a dual-input single-compartment model: absolute arterial blood flow (Fa), absolute portal venous blood flow (Fp), absolute total liver blood flow (Ft) (Ft = Fa + Fp), arterial fraction (ART), portal venous fraction (PV), distribution volume (DV), and mean transit time (MTT) of gadopentetate dimeglumine. Patients were assigned to ...
Monoplacophorans and the Origin and Relationships of Mollusks

The story of the discovery and study of the Monoplacophora (or Tryblidia) and how they have contributed to our understanding of the evolution of the Mollusca highlights the importance of integrating data from the fossil record with the study of living forms. Monoplacophora were common in the early Paleozoic and were thought to have become extinct during the Devonian Period, approximately 375 Mya. In the mid 1950s, they were recovered from abyssal depths off of Costa Rica and were immediately heralded as a “living fossil.” The living specimens confirmed that some of the organs (kidneys, heart, and gills) were repeated serially, just like the shell muscles that had been observed in fossil specimens. This supported the hypothesis that they were closely related to other segmented organisms such as annelids and arthropods. Today, there are 29 described living species and a growing body of work examining their anatomy, phylogeny, and ecology. Additional fossil specimens have also been discovered, and what was once thought to be a possible missing link between annelid worms and mollusks now appears to be a highly specialized branch of the molluscan tree that tells us little about the ancestral mollusk condition. However, some assumptions and generalizations from those early days still remain—such as the abyssal nature of the living species. A large part of the evolutionary history of the lineage remains to be discovered and will likely prove more complicated and interesting than afforded by the living fossil designation.
Operative hysteroscopy in physiologic distention media

Abstract Distention media are essential in operative hysteroscopy to ensure good visualization within the uterine cavity. Carbon dioxide, dextran-70, glycine, sorbitol, mannitol, saline, and Ringer's lactate solution have all been used, but are associated with difficulties that prevent their use with instruments that achieve appropriate current densities. Three new distention media are now available that correct problems associated with the earlier products.
Chemotherapy Induces Tumor Clearance Independent of Apoptosis

Dysregulation of apoptosis is associated with the development of human cancer and resistance to anticancer therapy. The ultimate goal of cancer treatment is to selectively induce cancer cell death and overcome drug resistance. A deeper understanding of how a given chemotherapy affects tumor cell death is needed to develop strategically designed anticancer agents. Here, we use a xenograft mouse tumor system generated from genetically defined cells deficient in apoptosis to examine the involvement of multiple forms of cell death induced by cyclophosphamide (CP), a DNA alkylating agent commonly used in chemotherapy. We find that although apoptosis facilitates tumor regression, it is dispensable for complete tumor regression as other forms of cell death are activated. Sporadic necrosis is observed in both apoptosiscompetent and deficient tumors evident by tumor cell morphology, extracellular release of high mobility group box 1 protein, and activation of innate immune cells in CP-treated tumors. Our findings indicate that in apoptosis-deficient tumors, necrosis may play a fundamental role in tumor clearance by stimulating the innate immune response. [Cancer Res 2008;68(23):9595–600]
Intravaginal administration of 9-deoxo-9-methylene-16,16-dimethyl PGE2 for cervical dilation prior to suction curettage

Abstract The use of prostaglandin for “priming” the cervix may avoid the pain and potential injuries associated with the rapid instrument dilation of a suction curettage. Prostaglandins appear to be able to soften and dilate the cervix, so that mechanical dilation is usually unnecessary. The results of the present study indicate that a single 16,16-dimethyl PGE 2 vaginal suppository is apparently adequate for achieving this effect as well as having relatively minimal side effects.
Atomic layer deposition of tantalum nitride for ultrathin liner applications in advanced copper metallization schemes

A metal–organic thermal atomic layer deposition (ALD) approach was developed for the growth of ultrathin tantalum nitride (TaNx) films by alternate pulses of tert-butylimido trisdiethylamido tantalum (TBTDET) and ammonia (NH3). An optimized ALD process window was established by investigating saturation of film-growth rate versus TBTDET and NH3 exposures, as controlled by the length of reactant pulses and the duration of the inert gas purge cycles separating the reactant pulses. The resulting low-temperature (250 °C) ALD process yielded uniform, continuous, and conformal TaNx films with a Ta:N ratio of 1:1. Carbon and oxygen impurity levels were in the 5–8 at.% range. Associated film conformality in 100-nm trench structures with 11:1 aspect ratio was nearly 100%.
Tuning compiler optimizations for simultaneous multithreading

Compiler optimizations are often driven by specific assumptions about the underlying architecture and implementation of the target machine. For example, when targeting shared-memory multiprocessors, parallel programs are compiled to minimize sharing, in order to decrease high-cost, inter-processor communication. This paper reexamines several compiler optimizations in the context of simultaneous multithreading (SMT), a processor architecture that issues instructions from multiple threads to the functional units each cycle. Unlike shared-memory multiprocessors, SMT provides and benefits from fine-grained sharing of processor and memory system resources; unlike current multiprocessors, SMT exposes and benefits from inter-thread instruction-level parallelism when hiding latencies. Therefore, optimizations that are appropriate for these conventional machines may be inappropriate for SMT. We revisit three optimizations in this light: loop-iteration scheduling, software speculative execution, and loop tiling. Our results show that all three optimizations should be applied differently in the context of SMT architectures: threads should be parallelized with a cyclic, rather than a blocked algorithm; non-loop programs should not be software speculated and compilers no longer need to be concerned about precisely sizing tiles to match cache sizes. By following these new guidelines compilers can generate code that improves the performance of programs executing on SMT machines.