cssi/SciSciGPT-SciSciNet huggingface dataset:
Six titans of the Cambridge School: a review article

(Reviewing: Great Thinker in Economics, Series Editor, A. P. Thirlwall, selection consisting of P. Groenewegen, Alfred Marshall, 2007; P. Davidson, John Maynard Keynes, 2007, 2009; G. Fletcher, Dennis Robertson, 2008; A. Roncaglia, Piero Sraffa, 2009; G. C. Harcourt and P. Kerr, Joan Robinson, 2009; J. E. King, Nicholas Kaldor, 2009, Palgrave Macmillan) Six volumes in the Great Thinker in Economics Series were chosen by the Editors for this review, which focuses on The Cambridge School of Economics, so very different from the mainstream theory of general economic equilibrium which gives formal expression to Lionel Robbins' famous definition of the subject as the allocation of scarce means among alternative uses. In recognition of a distinct Cambridge School, the authors of these volumes present a variety of arguments within which three overlapping themes can be discerned: the relationship between ethics and economics; the role of stocks and flows in economic analysis; and the epistemic problem surrounding the role of creativity, which has eluded the skills of formalists. The once pervasive influence of Alfred Marshall, John Maynard Keynes, Dennis Robertson, Piero Sraffa, Joan Robinson and Nicholas Kaldor can only be recovered with some such set of general themes in mind. Copyright The Author 2011. Published by Oxford University Press on behalf of the Cambridge Political Economy Society. All rights reserved., Oxford University Press.
Developments in random field modeling

Abstract The paper gives a brief account of a new approach to the representation and analysis of homogeneous random fields. Attention is drawn to the problem of the excessive sensitivity (to the choice of correlation model) of the mean square derivatives upon which level excursion and extreme value statistics depend. This problem can be resolved for practical purposes by permitting some “local averaging” of the random field under study.
Reactions of Alkyl Azides and Ketones as Mediated by Lewis Acids: Schmidt and Mannich Reactions Using Azide Precursors

The Lewis acid-promoted reactions of alkyl azides with ketones can afford several products. Chief among these result from a Schmidt-like insertion of the azide into the carbon−carbon bond adjacent to the carbonyl group. Alternatively, an acid-promoted rearrangement of the azide to an iminium species can occur, mostly with benzylic azides; the iminium species can then be trapped by the enol of the carbonyl compound in a variation of the Mannich reaction. The scope of each of these reactions, the dependence of the observed products upon azide and ketone structure, and the nature of acid promotion are discussed. In broad strokes, cyclohexanones and other cyclic ketones react in the presence of TiCl4 to afford insertion products, whereas the Mannich route predominates when benzyl azide and triflic acid are used. The features that lead to each reaction type and possible mechanistic implications are discussed.
Transmission of water and ions through crosslinked hydrophilic membranes

Abstract In order to develop better semipermeable membranes for reverse osmosis, the mechanism of water transport must be determined. An evaluation of existing theories led to the hypothesis that degree of crosslinking and polar group content of a polymer were important factors in determining its semipermeability. This hypothesis was tested by preparing a series of crosslinked reinforced mem branes by polymerization in a thin film between two plates. These membranes were copolymers of ethylene glycol monomethacrylate (EGM), ethyl methacrylate (EM), and ethylene glycol dimethacrylate (EGD). High-pressure reverse osmosis experiments with a sodium chloride solution and water sorption tests were then conducted and the results were correlated with the degree of crosslinking and hydroxyl content of the membranes. For copolymers of EGM and EGD, the degree of salt rejection rose as the membrane was more tightly crosslinked, then dropped off sharply. The rise was attributed to a decrease in translational motion of the polymer chain segments relative to one another, with associated hindrance to ion diffusion. The fall was due to monomersolvent incompatibility during polymerization with attendant precipitation of the polymer forming under these conditions, resulting in macrovoids in the membrane structure. As a result, water flux increased as the membrane was more highly crosslinked. Crosslinking had a great effect on water sorption. Copolymers containing EM showed virtually none of the semipermeability of EGM polymers. Water flux dropped off very rapidly, and salt rejection was not measurable. Perhaps most striking was the fact that water sorption tests showed a direct proportionality between hydroxyl content of the polymer and water sorption capacity.
Appearance of inflection point modes in beam-plasma systems

Abstract In a stable unbounded Vlasov-Poisson plasma, the phase velocity of a neutrally stable mode with non-zero wavenumber must correspond to a point on the equilibrium distribution which is simultaneously a critical point and an inflection point. The appearance of such inflection point modes in the spectrum of beam-plasma systems occurs when the linear stability boundary develops a minimum at the wavenumber of the mode. In this event, the boundary of the parameter domain of linear instability coincides with the boundary of the parameter domain of rigorous (nonlinear) stability.
Protein expression tells only half the story

A new mutation in wspF allows Pseudomonas fluorescens to colonize a previously unoccupied niche, but its proteomic effects reflect only a fitness cost. Between these two observations lies a better understanding of how organisms build and modify networks of protein expression through evolutionary time.
Decreased pokeweed mitogen‐induced igm and igm rheumatoid factor synthesis in rheumatoid arthritis patients treated with gold sodium thiomalate or penicillamine

Prospective and retrospective analysis of data obtained on 119 patients with rheumatoid arthritis suggested a relationship between clinical response induced by gold salts or D-penicillamine and decreased in vitro antibody synthesis by peripheral blood mononuclear cells. A subgroup of 21 patients with inactive disease receiving these drugs was found to have decreased pokeweed mitogen-induced in vitro synthesis of IgM and IgM rheumatoid factor. Detailed analysis of the cellular mechanisms responsible for this decreased responsiveness demonstrated markedly decreased B cell function. Patients treated with D-penicillamine also had altered T cell helper function manifested by incomplete reconstitution of the normal IgM response, while patients treated with gold salts had normal T cell function. Monocytes appeared not to have a major role in the decreased in vitro responsiveness. The results suggest that, in patients who respond to gold salts or D-penicillamine, antibody synthesis by circulating B cells is profoundly decreased, probably due to an indirect effect of these disease-modifying agents.
769 ASSIGNMENT OF THE HUMAN GENE FOR LIVER TYPE PHOSPHO-FRUCTOKINASE ISOZYME TO CHROMOSOME 21 USING SOMATIC CELL HYBRIDS

Human phosphofructokinase (PFK, E.C.2.7.1.11) is under the control of three structural loci which code for M (muscle), L (liver), and P (platelet) type subunits. Human diploid fibroblasts express all 3 genes; random tetramerization of resulting subunits produces various isozymes. We have analyzed 17 human x Chinese hamster hybrids segregating human chromosomes for the expression of human L subunits. Since electrophoresis does not distinguish between the rodent or human PFKs,we employed an antihuman L monoclonal antibody which does not react with rodent PFK. The expression of human L subunits in the hybrids was detected by the enzyme-immunoprecipitation technique using staphylococci bearing protein A as an immunoadsorbent. 12 out of 17 hybrids expressed human L subunits and retained chromosome 21 whereas 5 did not express human PFKL and lacked chromosome 21. There was discordant segregation of all other human chromosomes and PFKL expression in these hybrids. The mean RBC PFK of 6 individuals with trisomy 21 was found to be elevated (147% of normal). A specific increase in L subunits in trisomic RBC was evident chromatographically by an increase in L-4 species and immunologically by decreased precipitation with anti-M monoclonal antibody. We conclude that the PFKL gene is located on chromosome 21 and that the previously noted elevation of RBC PFK in individuals with trisomy 21 is due to a gene dosage effect.
Study of two-neutron radioactivity in the decay of 26O.

A new technique was developed to measure the lifetimes of neutron unbound nuclei in the picosecond range. The decay of $^{26}\mathrm{O}\ensuremath{\rightarrow}^{24}\mathrm{O}+n+n$ was examined as it had been predicted to have an appreciable lifetime due to the unique structure of the neutron-rich oxygen isotopes. The half-life of $^{26}\mathrm{O}$ was extracted as ${4.5}_{\ensuremath{-}1.5}^{+1.1}(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}3(\mathrm{syst})\text{ }\text{ }\mathrm{ps}$. This corresponds to $^{26}\mathrm{O}$ having a finite lifetime at an 82% confidence level and, thus, suggests the possibility of two-neutron radioactivity.
DNA repair mechanisms in dividing and non-dividing cells

DNA damage created by endogenous or exogenous genotoxic agents can exist in multiple forms, and if allowed to persist, can promote genome instability and directly lead to various human diseases, particularly cancer, neurological abnormalities, immunodeficiency and premature aging. To avoid such deleterious outcomes, cells have evolved an array of DNA repair pathways, which carry out what is typically a multiple-step process to resolve specific DNA lesions and maintain genome integrity. To fully appreciate the biological contributions of the different DNA repair systems, one must keep in mind the cellular context within which they operate. For example, the human body is composed of non-dividing and dividing cell types, including, in the brain, neurons and glial cells. We describe herein the molecular mechanisms of the different DNA repair pathways, and review their roles in non-dividing and dividing cells, with an eye toward how these pathways may regulate the development of neurological disease.
Esophageal stenting for malignant and benign disease: 133 cases on a thoracic surgical service.

Background Esophageal stenting is increasingly being utilized to treat a variety of benign and malignant esophageal conditions. The aim of our study was to review our experience with self-expanding metal, plastic, and hybrid stents in the treatment of esophageal disease on a thoracic surgical service. Methods The study population consisted of 126 patients undergoing placement of 133 stents at a single institution from 2000 to 2008. Data were reviewed retrospectively for patient characteristics, indications, complications, reinterventions, and efficacy. Results Most stents were placed for palliation of dysphagia due to advanced esophageal cancer (90 of 133; 68%) or extrinsic compression from lung cancer (13 of 133; 9.8%). A total of 123 self-expanding metal stents (SEMS), 7 self-expanding plastic stents (SEPS), and 3 hybrid stents were placed. Of the SEMS, 57 were uncovered and 66 were covered. Malignant obstruction was typically palliated with SEMS, while covered stents were chosen for perforations or anastomotic leaks. The median length of stay was 1 day. Complications occurred in 38.3% of stent placements, with a single perioperative mortality resulting from massive hemorrhage on postoperative day 4. Most complications resulted from stent impaction (12.8%), migration (9.7%), or tumor ingrowth (5.3%). Tumor ingrowth was uncommon with uncovered stents (2 of 57; 3.5%). Stent migration was common with SEPS (4 of 7; 57%), or hybrid stents (2 of 3; 67%). Survival was short in patients with underlying malignancy (median 104 days for esophageal cancer and 48 days for lung cancer), with 20% of patients surviving less than 1 month. Conclusions Esophageal stent placement is safe and reliable. The goals of therapy are typically met with a single intervention. The majority of patients require no further interventions, though life expectancy often is short and patient selection may be difficult. Most complications are due to stent obstruction, though stent migration is an issue particularly with SEPS and hybrid stents. Esophageal surgeons should be adept at stent placement.
Fine‐Grained Ferrites. II. Ni1−xZnxFe2O4

A series of fine-grained single-phase ferrites was prepared according to the formula Ni1−x Zn x Fe2O4, where x took the values 0, 0.10, 0.33, 0.50, and 0.67. A previously-described process combining the so-called flame-spraying and hot-pressing techniques was used to obtain grain sizes of approximately 0.1 micron in the densified bodies, μ′ and μ″ were measured to 1000 Mc, with grain size and composition as parameters. Measurements were also made to 3800 Mc on a ferrite annealed through the critical size for multi-domains, confirming previously-reported theory that magnetic poles on the domain walls are the source of the microwave peak at about 2000 Mc. Wall displacement appears to contribute to the static μ0 in large-grained ferrites when x>0.
Changes in Vocal Fundamental Frequency at the Segmental Level

in addition to cycle-by-cycle (jitter) and long-term (intonation contour and declination) changes, vocal fundamental frequency (F0) is known to vary during moments of production of individual phone...
Nerve-muscle networks in the accessory gland tubules of a male insect: Structural and physiological properties

Abstract The accessory gland tubules of the cockroach Leucophaea maderae , (F.) are innervated by the phallic nerves which arise from the terminal ganglion. Tubule preparations stained with methylene blue showed that a fine network of nerve fibres covers the entire surface of the tubule with putative nerve cells at various points. Muscle fibres of the tubules were arranged in an irregular lattice and appeared as flattened elipses approx 8–10 μm across and 1.5 μm in thickness. These muscles were monomyofibrillar with a poorly developed T -tubule system and a diffuse Z band. Innervation of the muscles showed abundant evidence of neurosecretomotor-type terminals. Clear evidence was also obtained for a multiterminal-type innervation. Accessory gland tubules had a basic wave-like pattern of motion in vitro which showed a wide variation in the time-course of each swing (1–50 s). A twisting and curling motion of the tubules was also recorded. Spontaneous junctional potentials were observed in accessory gland preparations isolated from the terminal ganglion. The duration for junction potential ranged between 30–140 ms. Action potentials recorded from muscles had a slower rise time and a longer duration (230–530 ms).
Learners' Interpretations of Recasts.

A number of interaction researchers have claimed that recasts might be ambiguous to learners; that is, instead of perceiving recasts as containing corrective feedback, learners might see them simply as literal or semantic repetitions without any corrective element (Long, in press; Lyster & Ranta, 1997). This study investigates learners' interpretations of recasts in interaction. Videotapes of task-based interactions including recasts and repetitions were shown to advanced English as a second language students (N = 34). Although both groups viewed the teacher's feedback (recasts, repetitions, or other), one group saw video clips that had been edited to remove the learners' nontargetlike utterances that had triggered the feedback, and another group saw the same video clips with the initial nontargetlike utterances included. After each clip, learners in both groups were asked to indicate whether they thought they were hearing a recast, a repetition, or something else. A subset of learners (n = 14) provided verbal reports while they evaluated the clips. Results show that learners who did not overhear initial learner utterances were significantly less successful at distinguishing recasts from repetitions. The verbal protocol data suggest that learners were not looking for nonverbal cues from the speakers. A post hoc analysis suggests that morphosyntactic recasts were less accurately recognized than phonological or lexical recasts in this study. These findings suggest that the contrast between a problematic utterance and a recast contributes to learners' interpretations of recasts as corrective.
The fatty acids of wax esters and sterol esters from vernix caseosa and from human skin surface lipid.

Separation of sterol esters from wax esters in the lipids of vernix caseosa and adult human skin surface was accomplished by column chromatography on MgO. The fatty acids of the sterol esters and wax esters of both samples were separated into saturates and monoenes, and examined in detail by gas liquid chromatography (GLC). The saturated fatty acids of the wax esters of vernix caseosa and of adult human skin surface were remarkably similar. They ranged in chain length from at least C11 to C30, six skeletal types being present: straight even, straight odd, iso, anteiso, other monomethyl branched and dimethyl branched. A large number of patterns of monoenes were observed, each pattern consisting of desaturation of a specific chain at Δ6 or Δ9 plus its extension or degradation products. The mole per cent of the total Δ6 and Δ9 patterns of wax ester fatty acid monoenes of vernix caseosa were 87% and 12%, respectively, and 98% and 1%, respectively, for adult human skin surface lipid. The sterol ester fatty acids of vernix caseosa were much different from those of adult human skin surface: vernix caseosa saturates were largely branched and of lengths greater than C18, whereas the saturates of adult human surface lipid resembled the wax ester fatty acids. Of the vernix caseosa monoene patterns, the mole per cent was 30% Δ6 and 70% Δ9, whereas of the adult human skin surface sterol ester fatty acids 89% were Δ6 and 11% Δ9. Chain extension was particularly pronounced in the sterol ester fatty acid monoenes of vernix caseosa amounting to 7–8 C2 units in some cases. The fatty acids of the sterol esters of both vernix caseosa and adult human skin surface appear to be derived from the sebaceous gland and from the keratinizing epidermis, but those of the wax esters are from the sebaceous glands only.
A general purpose XUV laser spectrometer: some applications to N2, O2 and CO2

Abstract Coherent radiation is generated from 90 to 105 nm by frequency tripling the frequency-doubled output of a pulsed Nd: YG-pumped dye laser using a synchronized pulsed jet of various gases as the nonlinear medium. The XUV radiation is isolated by a pair of dichroic mirrors before interacting with a supersonically cooled gas target. Provisions have been made to measure the photoion yield as a function of wavelength using a time-of-flight mass spectrometer. In addition absorption by the target gas or fluorescence from the excited target and/or its fragments can be detected. Some applications are presented which illustrate the versatility of this XUV laser spectrometer involving 1+1 resonance-enhanced multiphoton ionization of N2 and excitation of Rydberg states of O2 and CO2.
First measurements of timelike form factors of the hyperons, Λ0, Σ0, Σ+, Ξ0, Ξ−, and Ω−, and evidence of diquark correlations

Abstract Using 805 pb − 1 of e + e − annihilation data taken with the CLEO-c detector at ψ ( 3770 ) , s = 3770 MeV , we report the first measurements of the electromagnetic form factors of the Λ 0 , Σ 0 , Σ + , Ξ 0 , Ξ − , and Ω − hyperons for the large timelike momentum transfer of | Q 2 | = 14.2 GeV 2 . The form factors for the different hyperons are found to vary by nearly a factor two. It is found that | G M ( Λ 0 ) | = 1.66 ( 24 ) × | G M ( Σ 0 ) | . The Λ 0 and Σ 0 hyperons have the same uds quark content, but differ in their isospin, and therefore the spin of the ud quark pair. It is suggested that the spatial correlation implied by the singlet spin–isospin configuration in the Λ 0 is an example of strong diquark correlations in the Λ 0 , as anticipated by Jaffe and Wilczek. Improved measurements of the branching fractions of ψ ( 2 S ) → p p ¯ and hyperon–antihyperon pairs are also reported.
Electrokinetic Stretching of Tethered DNA

During electrophoretic separations of DNA in a sieving medium, DNA molecules stretch from a compact coil into elongated conformations when encountering an obstacle and relax back to a coil upon release from the obstacle. These stretching dynamics are thought to play an important role in the separation mechanism. In this article we describe a silicon microfabricated device to measure the stretching of tethered DNA in electric fields. Upon application of an electric field, electro-osmosis generates bulk fluid flow in the device, and a protocol for eliminating this flow by attaching a polymer brush to all silicon oxide surfaces is shown to be effective. Data on the steady stretching of DNA in constant electric fields is presented. The data corroborate the approximate theory of hydrodynamic equivalence, indicating that DNA is not free-draining in the presence of both electric and nonelectric forces. Finally, these data provide the first quantitative test of a Stigter and Bustamante's detailed theory of electrophoretic stretching of DNA without adjustable parameters. The agreement between theory and experiment is good.
Experimental investigations as a basis for treatment of type B hemophilus influenzae meningitis in infants and children

Summary Experimental results demonstrate that there is a close correlation between the mouse protective capacity of sulfonamides and their degree of inhibition in the test tube against type b H. influenzae. Sulfadiazine is vastly superior to sulfanilamide and definitely more effective than sulfapyridine. A simple in vitro test is described for estimating the susceptibility of a given strain to sulfadiazine within forty-eight hours of isolation. Sulfadiazine and type-specific rabbit antibody, when used singly,have been shown to possess approximately equal protective value against lethal type b H. influenzae mouse infections. However, regardless of the dose administered they fail to protect regularly when the inoculum exceeds 10,000 minimal lethal doses. Mice treated with both agents together quite regularly survive following the injection of 1,000,000 minimal lethal doses. It seems quite clear that in the treatment of patients with influenzal meningitis the risk of failure is reduced to a minimum by the use of both serum and sulfadiazine. However, if the infection is judged mild by clinical and laboratory criteria, initial treatment with chemotherapy alone is justified, provided the recommended precautions and guides are used and provided the strain shows average susceptibility to sulfadiazine.
Acoustic wave stimulation of low temperature ceramic reactions: The system Al2O3−P2O5−H2O

Acoustic energy has been primarily used in materials research to disaggregate solids and/or disperse them in fluids. It has also been used in a few studies to influence or cause new reactions in organic and organometallic systems. However, the potential of acoustic energy in the area of inorganic reactions and materials science has been virtually unexploited. We report herein new effects of acoustic waves in catalyzing reactions in the systems Al2O3 + H2O and Al2O3 + P2O5 + H2O. In this study the effect of different alumina precursors and their particle size on their reactivity with water and H3PO4 was investigated when exposed to 20 kHz waves.
Asymptotic freedom in hamiltonian light-front quantum chromodynamics

Abstract The leading ultraviolet divergent corrections to the quark-gluon vertex in light-front QCD are computed using hamiltonian perturbation theory, and accepted results are obtained only after cancellations of severe light-front infrared divergences. I argue that these singularities are unavoidable in a hamiltonian formulation, and that they may signal important effects in the full theory that are not apparent in perturbation theory. A demonstration of asymptotic freedom requires a light-front renormalization group, which is briefly discussed.
Diversity maximization under matroid constraints

Aggregator websites typically present documents in the form of representative clusters. In order for users to get a broader perspective, it is important to deliver a diversified set of representative documents in those clusters. One approach to diversification is to maximize the average dissimilarity among documents. Another way to capture diversity is to avoid showing several documents from the same category (e.g. from the same news channel). We combine the above two diversification concepts by modeling the latter approach as a (partition) matroid constraint, and study diversity maximization problems under matroid constraints. We present the first constant-factor approximation algorithm for this problem, using a new technique. Our local search 0.5-approximation algorithm is also the first constant-factor approximation for the max-dispersion problem under matroid constraints. Our combinatorial proof technique for maximizing diversity under matroid constraints uses the existence of a family of Latin squares which may also be of independent interest. In order to apply these diversity maximization algorithms in the context of aggregator websites and as a preprocessing step for our diversity maximization tool, we develop greedy clustering algorithms that maximize weighted coverage of a predefined set of topics. Our algorithms are based on computing a set of cluster centers, where clusters are formed around them. We show the better performance of our algorithms for diversity and coverage maximization by running experiments on real (Twitter) and synthetic data in the context of real-time search over micro-posts. Finally we perform a user study validating our algorithms and diversity metrics.
Optimal Bayesian cancer prognosis with model-constrained robust intervention

This work addresses optimal cancer prognosis under robust control relative to an uncertainty class of different subtypes or stages of cancer. Specifically, we model the inherent unpredictability of somatic gene mutations and aberrant pathway functioning in cancer by assuming that the precise regulatory relationships between genes, which relate to prognosis, belong to an uncertainty class of plausible mutations of some known healthy network. We implement model-constrained robust intervention relative to this uncertainty class, and train an optimal classifier to predict prognosis under this robust treatment given a snapshot of the patient gene activity profile. While accurate prognosis is possible, we show that performance depends on many factors.
Generalizing a quantum-well infrared single-pixel polarimeter (QWISPP) to Fourier transform spectral-polarimetric imaging

At previous SPIE meetings, we reported on an optoelectronic device that measures the complete polarization state of incident infrared light in a single pixel and in a single frame for a narrow wavelength band (δλ<0.05 μm). Using at least four quantum-well stacks and four linear gratings, each stacked alternating above the other, the device uses the interference among light paths to create a distinct pattern of photocurrents at each quantum-well stack coding for a specific polarization. In this paper, we will model the performance of this device, a quantum-well infrared single-pixel polarimeter (QWISPP), in the setting of a Fourier transform infrared (FTIR) imager. We model one column of QWISPP pixels detecting an inferferogram. Using an FTIR with randomly varying QWIsPP pixels to detect the interferogram, we discovered a technique that allows an 100x improvement in measured spectral-polarization uncertainty compared to the use of identical QWISPP pixels in an FTIR or grating spectrometer. The technique also enables a 15x improvement in the uniformity of the error across a sample spectrum. In other words, we turn into an advantage the imperfections in fabricating an FPA of QWISPPs.
Quality of erect-type blackberry fruit after short intervals of controlled atmosphere storage

Abstract ‘Navaho’ and ‘Arapaho’ blackberries ( Rubus sp.) were stored at 2 °C in ambient atmosphere (0.03 kPa CO 2 , 21 kPa O 2 ) or CA (15 kPa CO 2 , 10 kPa O 2 ) with the following treatments: 3 days of CA storage plus 11 days in air; 7 days of CA storage plus 7 days with air; 14 days of constant CA storage. Titratable acidity was higher after 3 and 14 days CA storage for ‘Arapaho’ and ‘Navaho’, respectively, compared with control fruit. At least 7 days of CA was needed to reduce incidence of decayed fruit in both cultivars. Monomeric anthocyanin content decreased 20% after 7 days CA storage compared with control blackberries for both cultivars. Consumer panels did not detect off-flavors in blackberries treated with CA for 3 or 7 days.
Microtubules and actin filaments: dynamic targets for cancer chemotherapy

Microtubules and actin filaments play important roles in mitosis, cell signaling, and motility. Thus these cytoskeletal filaments are the targets of a growing number of anti-cancer drugs. In this review we summarize the current understanding of the mechanisms of these drugs in relation to microtubule and actin filament polymerization and dynamics. In addition, we outline how, by targeting microtubules, drugs inhibit cell proliferation by blocking mitosis at the mitotic checkpoint and inducing apoptosis. The beta-tubulin isotype specificities of new anticancer drugs and the antitumor potential of agents that act on the actin cytoskeleton are also discussed.
Structural Change and Democratization in the Major Power Subsystem: Some Systemic Puzzles of the Democratic Peace

Two systemic puzzles of the democratic peace are examined within the context of the critical major power subsystem for the 1816–1992 period. One puzzle concerns whether the relationship between systemic democratization and conflict should be linear, curvilinear, or unpredictable. While the arguments for the latter two possibilities are persuasive, the empirical evidence suggests that the relationship is negative and linear in the major power subsystem. The second puzzle focuses on the relative strength of democratization, particularly, vis-a-vis hegemony, in reducing conflict. In contrast to earlier findings, structural change, conceptualized and measured in terms of global and regional power concentration patterns, in conjunction with democratization, predicts significantly to systemic levels of militarized dispute behavior. The democratic peace phenomenon thus works similarly at multiple levels of analysis but its emergence has not eliminated the explanatory utility of older emphases on geopolitical configurations and structural change. At the same time, we do not need to choose between old and new explanations, as long as we can integrate them into coherent and more compelling explanations than their stand-alone equivalents.
Hybrid Time- And Space-Integration Method For Computer Holography

A conceptually simple method for producing a hologram of a computer-specified object is to illuminate the photosensitive recording plate with a reference wave and trace out the object distribution with a point of light moved by a computer-controlled scanning system. The principal drawback is the poor signal-to-noise ratio (SNR) of the reconstructed object, because of bias buildup in the recording process. Two methods for improving reconstruction SNR are discussed in this paper: (1) maximizing the contrast of each fringe or zone-plate pattern exposing the hologram, and (2) recording intermediate holograms of portions of the object, which are then reconstructed for use in recording a final hologram of higher signal-to-bias ratio.
Traveling-wave induction launchers

An analysis of traveling-wave induction launchers shows that induction is a feasible method of producing armature current and that efficient accelerators can be built without sliding contacts or arcs. In a traveling-wave induction launcher the armature current is induced by a slip speed between the armature and a traveling magnetic field. At 9-m/s slip speed a 9-kg projectile with an aluminum armature weighing 25% of the total mass can be accelerated to 3000 m/s in a 5-m-long barrel with a total ohmic loss in the barrel coils and armature of 4% of the launch kinetic energy and with an average armature temperature rise of 220 degrees C, but a peak excitation frequency of 8600 Hz is required. With a 2-kg launch mass the ohmic loss is 7%. A launcher system optimized for rotating generators would have a peak frequency of 4850 Hz; with an aluminum armature weighing 33% of the launch mass and a slip speed of 30 m/s the total ohmic loss in the generators, cables, and accelerator would be 43% of the launch kinetic energy, and the average armature temperature rise would be 510 degrees C. >
Benzoyl cyanide in the defensive secretion of polydesmoid millipeds.

A novel cyanogenetic compound, benzoyl cyanide, was isolated from the defensive secretion of 3 polydesmoid millipeds (Pseudopolydesmus serratus, Apheloria corrugata and A. trimaculata). The secretion of the 3 species also contains mandelonitrile and benzaldehyde, and that of P. serratus contains mandelonitrile benzoate, benzoic acid, isovaleric acid, myristic acid and stearic acid.
Columnar growth in thin films.

A theory for the growth of columnar microstructures in thin films is presented. The zone-I to zone-II transition temperature is predicted. The surface morphology and the columnar grain structure are obtained both analytically and numerically, and the scaling behavior of the columnar grain size with film thickness is derived. Monte Carlo simulations are used to follow the evolution of the three-dimensional zone-II microsctuctures and to account for the formation of film texture. These results agree with experimental observations.
Hall effect in copper and Cu3Au at low temperatures

Abstract The Hall coefficient in single crystals of copper and Cu 3 Au in the ordered and disordered states has been measured at temperatures down to 4°K. No dependence of the Hall coefficient on orientation in copper has been found. In all cases the Hall coefficient is found to be appreciably temperature-dependent.
Imaging seismic tomography in sensor network

Tomography imaging, applied to seismology, requires a new, decentralized approach if high resolution calculations are to be performed in a sensor network configuration. The real-time data retrieval from a network of large-amount wireless seismic nodes to a central server is virtually impossible due to the sheer data amount and resource limitations. In this paper, we present a distributed multi-resolution evolving tomography algorithm for processing data and inverting volcano tomography in the network, while avoiding costly data collections and centralized computations. The new algorithm distributes the computational burden to sensor nodes and performs real-time tomography inversion under the constraints of network resources. We implemented and evaluated the system design in the CORE emulator. The experiment results validate that our proposed algorithm not only balances the computation load, but also achieves low communication cost and high data loss tolerance.
Trends in emergency coronary artery bypass grafting after percutaneous coronary intervention, 1994-2003.

Background In the last decade, percutaneous coronary intervention (PCI) has undergone profound changes in techniques used to achieve revascularization and in patient selection. We examine trends in emergency surgical revascularization after PCI. Methods Using The Society of Thoracic Surgeons National Cardiac Surgery Database, we examined patients undergoing coronary artery bypass grafting within 6 hours of PCI from 1994 to 2003. Stratifying into groups of patients who had and had not suffered myocardial infarction within 24 hours of PCI followed by coronary artery bypass grafting (CABG), we tracked trends in characteristics, predicted risk, and clinical outcomes. Results The proportion of isolated CABG procedures done emergently after PCI decreased over 1994 to 1999 from 3,357 of 115,679 (2.9%) to 1,227 of 155,831 (0.8%), remaining stable through 2003. Those suffering myocardial infarction within 24 hours made up a constant proportion of isolated CABG as emergency after PCI (3,352 of 1,042,864; 0.3%) since 1997. Over the decade, the preoperative risk profile worsened, including more elderly patients and more with cerebrovascular disease and congestive heart failure. Operative mortality among these patients has risen with time (from 8.0% to 9.3%; p p Conclusions In 2005, there remains a low but real need for emergent CABG after PCI, in which operative outcomes are less than ideal, especially in the postinfarction patient, representing an area for cross-specialty collaboration.
Experimental design of systems involving multiple fluorescent protein reporters

Abstract Fluorescent proteins have found widespread applications for analysis of biological systems as they can be used to track various events within living cells. Multiple fluorescent proteins are also simultaneously used to monitor different aspects of biological systems. However, extensive overlap in the emission spectra of the fluorescent proteins poses challenges in extracting the contribution of individual proteins to overall fluorescence intensity measurements. This work addresses this issue by deriving a computational formulation for extracting the contribution of fluorescence intensities of individual reporters to the overall measurements taken using a plate reader. Then, this formulation is used for deriving an experimental design criterion for choosing sets of fluorescent proteins such that the accuracy of the estimated contribution of different fluorescent proteins is maximized. The results are validated using two sets of experimental data involving different sets of fluorescent proteins. This work represents the first quantitative study that evaluates experimental design for selection of fluorescent proteins to use simultaneously for multiple-labeling applications.
Improved a-Si1 − xGex:H of large x deposited by PECVD

Abstract By plasma enhanced chemical vapor deposition a-Si 1 − x Ge x :H thin films of large x have been prepared which possess optical, electrical and structural properties that are greatly improved over any yet reported. This work extends our previous work on improving the properties of a-Ge:H [W.A. Turner et al., J. Appl. Phys. 67 (1990) 7430]. Steady-state photoconductivity measurements yield an ημτ of (1 to 3) × 10 −7 cm 2 V −1 for 1.00 ≥ x ≥ 0.75 and (6 to 10) × 10 −8 cm 2 V −1 for 0.75 ≥ x ≥ 0.50. Photocarrier grating measurements yield an ambipolar diffusion length much greater than previously obtained for alloys of large x . The electronic state defect density, as determined by drive level capacitance measurements, decreases from 5.3 × 10 16 cm −3 for x = 1.00 to 6.5 × 10 15 cm −3 for x = 0.57. The Urbach parameter, E 0 , was found to be 41 ± 2 meV for a-Ge:H and 45 ± 2 meV for the alloys. Small angle X-ray scattering measurements reveal a structure that is nearly as homogeneous as device quality a-Si:H. Much of the improvement in electronic and optical properties is associated with the reduction of heterogeneities in the structure. The elimination of columnar structure is attributed to increased ion bombardment during growth and conditions which yield a high electron temperature in the discharge plasma, resulting in favorable discharge chemistry.
A structure-specific DNA endonuclease is enriched in kinetoplasts purified from Crithidia fasciculata

The mitochondrial DNA (kinetoplast DNA) of the trypanosomatid Crithidia fasciculata consists of minicircles and maxicircles topologically interlocked in a single network per cell. Individual minicircles replicate unidirectionally from either of two replication origins located 180 degrees apart on the minicircle DNA. Initiation of minicircle leading-strand synthesis involves the synthesis of an RNA primer which is removed in the last stage of replication. We report here the purification to near homogeneity of a structure-specific DNA endo-nuclease based on the RNase H activity of the enzyme on a poly(rA).poly(dT) substrate. RNase H activity gel analysis of whole cell and kinetoplast extracts shows that the enzyme is enriched in kinetoplast fractions. The DNA endonuclease activity of the enzyme is specific for DNA primers annealed to a template strand and requires an unannealed 5' tail. The enzyme cleaves 3' of the first base paired nucleotide releasing the intact tail. The purified enzyme migrates as a 32 kDa protein on SDS gels and has a Stoke's radius of 21.5 A and a sedimentation coefficient of 3.7 s, indicating that the protein is a monomer in solution with a native molecular mass of 32.4 kDa. These results suggest that the enzyme may be involved in RNA primer removal during minicircle replication.
Reconfigurable high-speed optoelectronic interconnect technology for multiprocessor computers

ABSTRACTWe describe a compact optoelectromc switching technology for interconnecting multiple computer processors and shared memory modules together through dynamically reconfigurable optical paths to provide simultaneous, high speed communication amongst different nodes. Each switch provides an optical link to other nodes as well as electrical access to anindividual processor, and it can perform optical and optoelectronic svitching to convert digital data between various electricaland optical input/output formats. This multi-functional switching technology is based on the monolithic integration of arrays of verucal-ca'tY surface-emitting lasers with photodetectors and heterojunction bipolar transistors. The various digital switching and routing functions, as well as optically cascaded multi-stage operation, have been experimentally demonstrated. 1. INTRODUCTION:As increasing numbers of high-speed digital processors are linked together to form interactive computer networksthat provide a parallel processing capability, there is a growing need for a high speed bus that allows many processors to
Randomized crossover trial comparing the eZ.on plastic condom and a latex condom.

This randomized crossover trial compared the breakage and slippage rates, safety, and acceptability of the recently developed polyurethane bi-directional eZ.on condom with a marketed latex condom. Three hundred sixty couples were asked to use 4 eZ.on condoms and 4 latex condoms. Like several other non-latex condoms tested to date, the eZ.on condom had a higher clinical breakage rate than its latex comparator, while the slippage rates were similar. The clinical breakage rate for the eZ.on condom was 5.6%, compared with 0.9% for the latex condom (difference = 4.76%, with upper 95% confidence bound on the difference = 6.26%). Thus, based on an a priori definition of a 2% clinically acceptable difference, the study failed to conclude equivalence relative to clinical breakage. The complete slippage rate for eZ.on was 1.6%; compared to 0.7% for latex (difference = 0.87%, with upper 95% confidence bound = 1.55%). Thus, based on an a priori definition of a 2% difference we concluded equivalence relative to complete slippage. The safety profile of the eZ.on condom was good and similar to the latex condom. The eZ.on was also found to be easier to don and remove than the latex condom. Although no overall preference existed for either condom, nearly 30%women and men strongly preferred the eZ.on condom to the latex condom. The eZ.on condom may be an acceptable alternative for couples unable or unwilling to use latex condoms.
Influence of peripheral cholinergic blocking drugs on survival time in x-ray irradiated mice.

In the paper by Haley and Rhodes that appeared on page 139, SCIENCE, February 6, there is reference to the compound Win-2299. This compound is known chemically as 2-diethyl-aminoethyl cyclopentylhydroxy-2-thienylacetate hydrochloride.
Rigid fixation of maxillary osteotomies: A review of treatment results

Although rigid fixation of maxillary osteotomies has several advantages, it is technically more demanding than wire osteosynthesis. Unsatisfactory postsurgical results can be traced to any of three phases of surgical treatment: preoperative, interoperative, and postoperative. The authors review these three phases of treatment and present cases in which the desired outcome was not initially achieved. The subsequent management of the patients is discussed.
An in vitro biomechanical investigation of an intramedullary nailing technique for repair of third metacarpal and metatarsal fractures in neonates and foals

Objective— To evaluate a dorsoproximal extra-articular approach for insertion of 8.25-mm, solid-titanium, intramedullary (IM) interlocking nails into ostectomized foal third metacarpal (MC3) and third metatarsal (MT3) bones; to compare the monotonic mechanical properties of IM nail constructs with paired intact bones; and to determine the effects of age, body weight, fore- or hindlimb, and left or right limb on the mechanical testing variables. Animal or Sample Population— Twenty bone pairs (10 MC3, 10 MT3) collected from 10 foals of various weights and ages. Methods— One bone from each pair was randomly selected to be ostectomized and stabilized using an 8.25-mm, solid-titanium IM nail, and four 3.7-mm titanium interlocking screws (construct). Constructs and contralateral intact bone specimens were tested in axial compression and palmaro-/plantarodorsal (PD) 4-point bending. Monotonic mechanical properties were compared between intact specimens and constructs with an ANOVA; significance was set at P < .05. Results— Nail insertion caused bone failure in 6 MC3 and 2 MT3. In general, mean mechanical testing values indicated that intact specimens were significantly stronger and stiffer than constructs for all age and weight ranges when tested in compression and PD 4-point bending (P < .05). Bone strength and stiffness of intact specimens tested in compression and bending tended to increase linearly with age and weight. Conclusions— IM interlocking nail fixation of gap-ostectomized MC3 and MT3 with 8.25-mm IM nails and 3.7-mm interlocking screws did not achieve sufficient strength or stiffness to be recommended as the sole means of repair for comminuted MC3 and MT3 fractures in young foals. Clinical Relevance— IM interlocking nail fixation of foal cannon bone fractures may be useful to decrease soft-tissue disruption at the fracture site; however, there is a risk of bone failure associated with extra-articular insertion. This method should be combined with other forms of external coaptation for added stability in axial compression and PD bending.