cssi/SciSciGPT-SciSciNet huggingface dataset:
Social implications of biotechnology

The amount of information that can be gained through prenatal genetic screening is unprecedented, leaving prospective parents who discover their fetus has a defect the choice of whether to continue the pregnancy. There is nothing new in this choice, which is legally and ethically defensible as a private decision protected by parents' procreative liberty, except for the fact that the decision can be made much earlier in the pregnancy and for many more genetic defects than could be screened for even a few years ago. While health care providers struggle to remain "neutral" in their provision of information, a potential discussion of the social implications of this testing is truncated in the rush to give consumers what they demand: more information. A frank discussion of the validity of eugenics and eugenic practices needs to accompany the technological advances being made in genetic testing. This paper will explore three potential points for such a discussion: (1) that our society lacks a moral vocabulary to articulate what might be unethical about private eugenic choices; (2) that unfettered access to genetic information about one's offspring will change and is changing the meaning of parenthood; and (3) that an American drive for self-improvement and the improvement of one's offspring will find a ready partner in the medical-pharmaceutical industry meeting and creating our need for more tests.
Microspectroscopic imaging and characterization of individually identified ice nucleating particles from a case field study

The effect of anthropogenic and biogenic organic particles on atmospheric glaciation processes is poorly understood. We use an optical microscopy setup to identify the ice nuclei (IN) active in immersion freezing (IMF) and deposition ice nucleation within a large population of particles collected on a substrate from an ambient environment in central California dominated by urban and marine aerosols. Multimodal microspectroscopy methods are applied to characterize the physicochemical properties and mixing state of the individual IN and particle populations to identify particle-type classes. The temperature onsets of water uptake occurred between 235 and 257 K at subsaturated conditions, and the onsets of IMF proceeded at subsaturated and saturated conditions for 235–247 K, relevant for ice nucleation in mixed-phase clouds. Particles also took up water and nucleated ice between 226 and 235 K and acted as deposition IN with onset temperatures below 226 K, a temperature range relevant to cirrus cloud formation. The identified IN belong to the most common particle-type classes observed in the field samples: organic coated sea salt and Na-rich, secondary, and refractory carbonaceous particles. Based on these observations, we suggest that the IN are not always particles with unique chemical composition and exceptional ice nucleation propensity; rather, they are common particles in the ambient particle population. The results suggest that particle-type abundance and total particle surface area are also crucial factors, in addition to particle-type ice nucleation efficiency, in determining ice formation within the particle population.
Next flu pandemic : What to do until the vaccine arrives?

Most scientists consider another influenza pandemic inevitable, but there is little information on how best to protect the public before a vaccine can be made available.
Streptococcus pneumoniae: Invasion and Inflammation

Streptococcus pneumoniae (the pneumoccus) is the leading cause of otitis media, community-acquired pneumonia, and bacterial meningitis. The success of the pneumococcus stems from its ability to persist in the population as a commensal and avoid killing by immune system. This chapter first reviews the molecular mechanisms that allow the pneumococcus to colonize and spread from one anatomical site to the next. Then, it discusses the mechanisms of inflammation and cytotoxicity during emerging and classical pneumococcal infections.
Measuring the Sea Surface Heat Flux and Probability Distribution of Surface Renewal Events

The net sea surface heat flux is a crucial parameter for quantitative measurements of air-sea gas exchange rates, as well as for climate models and simulations. Current techniques used to measure heat fluxes are based on direct radiative schemes and micro-meteorological parameterizations. The long time averages required by the meteorological estimates tend to obscure short time and space scale events. Our technique uses a single infrared camera in order to quantitatively estimate the parameters of a surface renewal model of heat transfer.Through the use of spatio-temporal image processing techniques the material derivative of the sea surface temperature with respect to time can be used to compute both the heat flux density, as well as the probability density function of the underlying surface renewal model. First results of our technique obtained at the Heidelberg Aeolotron showed excellent agreement to ground truth data.
The Flexibilisation of the Labour Market in EU

The flexibilisation of the markers of goods and services conduces to an existence of untypical forms of unemployment and labour contracts. The labour market responses on the low economic growth and uncertainty with the increasing number of part-time employment, lime-limited labour contract and with work during Sundays and holidays as well. The employers try to keep cost on low level with the maximization of capital effectiveness and with an effort to meet the consumer demand they try to survive on a very competitive market.
Metal to Metal Intramolecular Electron Transfer Across Peptide and Protein Bridges

Important to the field of monoelectronics [1] and biocomputers is the study of donor-acceptor bridged complexes (Figure 1) where the donor and acceptor are held at fixed distances in well defined and characterized systems. The understanding and control of single electron transfer reactions in such molecular assemblies — be it in solution, thin-films, or on modified electrodes, should allow the development of molecular electronic components capable of use in modern computational devices. Our interest in this area has centered on the use of synthetic peptides and proteins as components of these molecular assemblies. In this lecture I will review the advances we have made in the understanding and control of long range electron transfer reactions in donor-acceptor complexes in three systems where synthetic peptides and proteins are modified with metal ion probes in solution.
Morphological and structural properties of poly[bis(p‐phenylphenoxy)phosphazene]

Poly[bis(p-phenylphenoxy)phosphazene] (PB(4-Ph)PP) has been investigated employing X-ray diffraction technique and electron microscopy. Its unit cell dimensions were determined to be a = 4,18 nm, b = 1,83 nm and c = 0,957 nm with space group Pca21. At 21 5–220°C , PB(4-Ph)PP transforms into an anisotropic liquid-like phase corresponding to a new molecular ordering array. The thicker films are composed of the linked globules approximately 100 nm in diameter. Upon drawing, the globules transform into a rod-like morphology 15–40 nm in width and exhibit a highly oriented X-ray diffraction pattern. These unusual morphological features have been compared with features found in poly[bis(phenoxy)phosphazene] and poly[bis(halophenoxy)phosphazene] polymers. X-ray diffraction and crystallization results support a smectic-like side chain morphology.
The Entry-Deterring Effects of Inflexible Regulation

This paper investigates the signalling role of tax policy in promoting, or hindering, the ability of a monopolist to practise entry deterrence. We show that environmental policy can facilitate the incumbent firm's concealment of information from potential entrants, thus deterring entry, and yet entail welfare improvements. Furthermore, we demonstrate that entry deterrence is more likely to arise when environmental regulation cannot be rapidly revised across time if market conditions change (inflexible regimes) than when regulatory agencies can adjust environmental policy over time. Les effets de dissuasion de l'entree d'une reglementation inflexible. Ce texte examine le role de signalisation d'une politique fiscale qui promeut ou reduit l'habilete d'un monopole a pratiquer la dissuasion de l'entree de concurrents. On montre qu'une politique environnementale peut faciliter la dissimulation d'information par la firme en place vis-a-vis les concurrents potentiels, et donc les dissuader d'entrer, et pourtant engendrer des ameliorations de bien-etre. De plus, on montre que la dissuasion de l'entree est davantage susceptible d'emerger quand la reglementation environnementale ne peut pas etre revisee rapidement dans le temps si les conditions de marche se modifient (regimes inflexibles) que quand les agences de reglementation environnementales peuvent ajuster la politiques dans le temps.
The relationship of structure to pressor and oxytocic actions of isoleucine5 angiotensin octapeptide and various analogues

Abstract Isolated natural angiotensin I and synthetic angiotensin II have similar pressor activity but the latter has a much higher oxytocic activity. On a weight basis, the oxytocic activity of angiotensin II is about 1 8 that of oxytocin. Examination of analogues of angiotensin II demonstrate the following conditions must be met to have pressor and oxytocic activity: (a) the C-terminal amino acid must be l -phenylalanine, (b) the terminal carboxyl group must be free, (c) tyrosine must be present, and (d) the peptide must contain at least amino acids numbered 3 to 8. It is suggested that the spatial configuration of the molecule is an important aspect of the biological specificity of peptides in addition to the amino acid composition and sequence.
Distinct metabolic surrogates predict basal and rebound GH secretion after glucose ingestion in men.

Context: GH secretion declines rapidly after glucose ingestion and then recovers to higher-than-baseline levels (rebound GH release). Hypothesis: Selective metabolic markers predict the magnitude of glucose-suppressed GH release and postglucose rebound-like GH secretion. Design: Prospectively randomized crossover study of GH secretion after glucose vs. water ingestion. Setting: The study was conducted at a clinical translational research center. Participants: Sixty-nine healthy men aged 19–78 yr with a body mass index of 18–39 kg/m2 participated in the study. Outcomes: Outcomes included nadir vs. peak GH concentrations and basal vs. pulsatile GH secretion. Results: Mean nadir GH concentrations were determined positively by sex hormone binding globulin (SHBG) after glucose administration (R2 = 0.088, P = 0.0077). Peak rebound GH concentrations were related positively to adiponectin and negatively to computed tomography-estimated abdominal visceral fat (AVF) (R2 = 0.182, P = 0.00049) after glucose ingestion...
On the mechanism of ion exchange in zirconium phosphates—XXIV Exchange of alkali metal ions on γ-zirconium phosphate

γ-Zirconium phosphate, Zr(HPO4)2·2H2O, was found to vary in water content from about 1–3 moles without change in its interlayer spacing. Two types of ion exchange behavior were found with alkali metal cations. Lithium ion formed a two phase system up to about 25% of exchange. Then, a single exchanged phase existed to half exchange where the first endpoint occured. A single Li+ phase was also observed at higher loadings. With K+, Rb+ and probably Cs+ a single phase was obtained from very low loads to 50% uptake. The water content of these phases was low (∼ 1 mole) and their interlayer spacings less than that of the original γ-zirconium phosphate. Above 50% loading the water contents and interlayer spacings increased. Sodium ion exhibited features common to both types of behavior. Li+ and Na+ yielded reversible titration curves (exchange behavior) but K+ and Rb+ did not.
“Pravo na TRUP”: Power, Discourse, and the Body in the Poetry of Nina Iskrenko

A xcording to Jean Frangois Lyotard, in the postmodern age all metanarratives-grand ideologies that seek to explain all of human experience (for example, Christianity, Marxism and Freudianism)-have proven to be untenable in the face of events. As a result, a skepticism toward metanarratives has come to characterize postmodern culture. Different ideologies are seen in the postmodern age as freely competing for cultural influence, with no single one considered more authentic or closer to the truth than any other.' In Russia, specifically, the distrust of ideology that characterizes the postmodern era developed largely as a direct reaction toward political events. It resulted from the realization in the late 1960s-70s that the Soviet utopian project had failed and that Marxist-Leninist ideology had no inherent claim to the status of truth, but was only one in a series of many grand ideologies-Orthodoxy, Russian nationalism, Western humanism, and so on-that have at one time or another sought to define Russia. In response to this loss of faith in ideology, two distinct brands of postmodernist practice have emerged in both Russia and the West. Hal Foster has defined these two strains as "postmodernism of resistance" and "postmodernism of reaction."2 Postmodernism of reaction asserts that all ideologies are equally disconnected from reality, and it aims to debunk them but does not seek to change the status quo. It maintains that "all positions in culture and politics are now open and equal ... that anything goes"-and that nothing can be done about such a situation. By contrast, postmodernism of resistance protests against the status quo and seeks to alter it. While postmodernism of reaction plays for play's sake with preestablished ideological structures and the language in which
Activins as candidate cholinergic differentiation factors in vivo

A number of cytokine families have been implicated in shaping neuronal survival, growth and gene expression. The neuropoietic and transforming growth factor-β (TGF-β) cytokines, in particular, have emerged as candidates for regulating the phenotype of sympathetic neurons. Culture studies have shown that neuropoietic cytokines (such as leukemia inhibitory factor, ciliary neurotrophic factor, oncostatin M, growth promoting activity) can induce the cholinergic enzyme, choline acetyltransferase (ChAT) and several neuropeptides, whereas certain members of the TGF-β family (activin A, bone morphogenetic proteins-2 and -6) induce partially overlapping but distinct sets of transmitter and neuropeptide genes in sympathetic neurons. Since activins can induce ChAT in cultured neurons, we have investigated whether these cytokines are expressed by the appropriate cells and tissues to make them candidates for the cholinergic differentiation factor that is known to alter the phenotype of sympathetic neurons that innervate the sweat gland in the footpad in vivo. In-situ hybridization with the anti-sense probe for activin βB specifically labels the sweat glands but not other tissues in the footpads of developing rats. Ribonuclease protection assays indicate that βB as well as the other activin and inhibin subunit mRNAs are expressed by a number of tissues, including footpad, hairy skin and submaxillary gland. Homogenates of developing rat footpads, however, failed to induce the set of neuropeptide genes in cultured sympathetic neurons that is characteristic for activins, although neuropoietic cytokine activity was readily detectable in this assay. Thus, while activin βB mRNA is expressed in the sweat gland, this tissue does not contain detectable activin protein as assayed by its ability to regulate neuronal gene expression. Moreover, activin subunit mRNAs are expressed by targets of noradrenergic sympathetic neurons in vivo, indicating that activin expression is not limited to targets of cholinergic neurons.
Natural killer activity of lymphocytes infiltrating human lung cancers following preoperative systemic recombinant interleukin 2.

• Tumor-infiltrating lymphocytes (TILs) show depressed natural killer (NK) activity compared with peripheral blood lymphocytes (PBLs). To determine if TIL NK function can be reactivated in vivo, 11 patients with tumors metastatic to the lung were treated with systemic recombinant interleukin 2 (rlL-2). Spontaneous TIL NK activity and NK activity after three days' incubation with 100 U/mL of rlL-2 were increased in patients receiving 15000 U/kg of rlL-2 preoperatively compared with those receiving between 1000 and 10000 U/kg. Histologically, higher doses of rlL-2 increased the number of intratumoral lymphocytes, the level of peritumoral lymphocytic transferrin, and the expression of HLA-DR. Spontaneous PBL NK activity in patients receiving between 10000 and 15000 U/kg of rlL-2 was also increased and was further increased by in vitro culture with rlL-2. Thus, PBL NK activity and TIL NK function in vivo can be augmented with 15000 U/kg of systemic rlL-2. Both TIL- and PBL-inducible cytotoxicities were further enhanced by in vitro culture with rlL-2. ( Arch Surg 1987;122:1446-1450)
Measurements of neutrino electron scattering

Neutrino electron elastic scattering can be measured with great sensitivity at a spallation neutron source using an oil or water Cerenkov detector. The value of sin2θW can be determined to less than 2% at low q2 and searches performed for neutrino magnetic moments and several exotic physics processes.
Diverse cellular and molecular modes of axon degeneration

The elimination of large portions of axons is a widespread event in the developing and diseased nervous system. Subsets of axons are selectively destroyed to help fine-tune neural circuit connectivity during development. Axonal degeneration is also an early feature of nearly all neurodegenerative diseases, occurs after most neural injuries, and is a primary driver of functional impairment in patients. In this review we discuss the diversity of cellular mechanisms by which axons degenerate. Initial molecular characterization highlights some similarities in their execution but also argues that unique genetic programs modulate each mode of degeneration. Defining these pathways rigorously will provide new targets for therapeutic intervention after neural injury or in neurodegenerative disease.
Network delay considerations for packetized voice

Abstract The potential cost benefit from integrating data and voice in a single network provides a strong motivation for packetized voice transmission. In this study, simulation models are used to characterize the delay distribution of voice packets in a single hop as well as in a multi-hop network environment. The trade-off between the number of speakers that can be multiplexed using speech activity detection technique and the delay performance are quantified. This is contrasted with the performance obtained by using a lower bit-rate voice input without speech activity detection. Finally, a procedure is presented which guarantees that the delay for any packet belonging to a call will not exceed a given value throughout the duration of the call, once the call is set up. This procedure can be used with or without speech activity detection.
A case of the Carney triad.

ABSTRACT Objective To report a case of mediastinal paraganglioma in the setting of the Carney triad (gastric leiomyosarcoma, extra-adrenal paraganglioma, and pulmonary chondroma). Methods A case of the Carney triad is presented, and the related literature is discussed. Results A 47-year-old woman with a history of gastric leiomyosarcoma and retroperitoneal paraganglioma sought medical attention because of progressive shortness of breath. She was found to have a mediastinal mass in the aortopulmonary window. The patient had normal blood pressure and normal urinary catecholamines, but metaiodobenzylguanidine scintigraphy showed an intense uptake in the region of the mass, consistent with paraganglioma. She subsequently underwent resection of the mediastinal mass, and the surgical pathology report indicated paraganglioma. Conclusion Patients with the Carney triad can have multicentric paragangliomas. Metaiodobenzylguanidine scanning may be helpful in the diagnostic workup. (Endocr Pract. 1999;5:266-268)
Global climate change: defining the policy problem

The U.S. appears to be misdefining the policy problem posed by the threat of global climate change, and is therefore not likely to find satisfactory policy solutions.
Endoluminal procedures for bariatric patients: expectations among bariatric surgeons

Abstract Background Primary and revisional bariatric endoluminal procedures are currently being developed. Acceptable levels of risk and weight loss for these procedures have not yet been established. The aim of this study was to evaluate the expectations and concerns among bariatric surgeons regarding these procedures. Methods The American Society for Metabolic and Bariatric Surgery Emerging Technologies Committee developed a questionnaire that was distributed to the membership. Risk tolerance was assessed with comparison to commonly performed endoscopic and bariatric procedures. The percentage of excess weight loss (EWL) ranges were provided to assess the expectations for results 1 year after the procedure. Results A total of 214 responses were returned. The acceptable level of risk to achieve 10–20% EWL after primary and revisional procedures was equivalent to, or less than, that of a therapeutic endoscopic procedure for 81% and 76% of respondents, respectively. The acceptable level of risk to achieve 30–40% EWL after primary and revisional procedures was equivalent to that after laparoscopic adjustable gastric banding for 45% and 35% of respondents, respectively and equivalent to that after laparoscopic Roux-en-Y gastric bypass for 8% and 22%, respectively. In addition, 62% of respondents responded that 10–30% EWL would be acceptable for revisional procedures, and 35% responded that 10–30% EWL would be acceptable after a primary procedure. The primary concern was unproven efficacy, followed by durability, poor weight loss, availability of equipment, and procedural risk. Finally, 58% would not be willing to recommend an endoluminal procedure until the efficacy has been established, regardless of the risk. Conclusion Risk tolerance and weight loss expectations among bariatric surgeons are different for primary and revisional endoscopic procedures. Most surgeons were unwilling to consider endoluminal procedures for their patients until the efficacy has been proven.
Coupling in PBG material with high group index

Abrupt discontinuity in the broad band density of states in a photonic crystal near PBG and low group velocity can have practical impact in many exiting applications of photonic crystals, for example, optical transistor, tunable filters, chromatic dispersion compensators and pulse compression. However it is difficult to excite EM modes in the photonic crystal at frequency close to its PBG by external beam because of tremendous group index mismatch. To solve this problem we propose an idea of a transition interface with a smooth group index profile. Firstly, the idea has been investigated in general using a multi-layer stack as a “toy” model. Then, general trends have been verified for 2D photonic crystals with infinite thickness and slab photonic crystals with one-dimensional periodicity. It has been shown that if there is no interface, reflection/back-diffraction from the photonic crystal at the frequency in the transmission window near its edge is close to 100%. However in case of transition interfaces the transmission increases and abrupt edge of the broad band transmission spectrum takes place. The thicker transition interface - the more abrupt transmission spectrum. It has been shown that not only thickness, but also the group velocity profile in the transition interface is essential.
Matrix metalloproteinase inhibition by heterotrimeric triple-helical Peptide transition state analogues

Matrix metalloproteinases (MMPs) have been implicated in numerous pathologies. An overall lack of selectivity has rendered active-site-targeted MMP inhibitors problematic. The present study describes MMP inhibitors that function by binding both secondary binding sites (exosites) and the active site. Heterotrimeric triple-helical peptide transition-state analogue inhibitors (THPIs) were assembled utilizing click chemistry. Three different heterotrimers were constructed, allowing for the inhibitory phosphinate moiety to be present uniquely in the leading, middle, or trailing strand of the triple helix. All heterotrimeric constructs had sufficient thermally stability to warrant analysis as inhibitors. The heterotrimeric THPIs were effective against MMP-13 and MT1-MMP, with Ki values spanning 100-400 nM. Unlike homotrimeric THPIs, the heterotrimeric THPIs offered complete selectivity between MT1-MMP and MMP-1. Exosite-based approaches such as this provide inhibitors with desired MMP selectivities.
Separation of phenytoin and its metabolites by high-performance liquid chromatography.

Abstract A method is described for separation of phenytoin (DPH) and its metabolites diphenylhydantoic acid (DPHA), 5-(3,4-dihydroxy-1,5-cyclohexadien-1-yl)-5-phenylhydantoin (DPH-dihydrodiol), 5-(4-hydroxyphenyl)-5-phenylhydantoin (p-HPPH), 5-(3-hydroxyphenyl)-5-phenylhydantoin (m-HPPH), and 5-(3-methoxy-4-hydroxyphenyl)-5-phenylhydantoin (DPH-3-0-met-catechol) in urine from mice and rats after administration of 14 C-DPH. The procedure involves β-glucuroidase hydrolysis, extraction with ethyl acetate, and high-performance liquid chromatography utilizing a C18 reversed-phase column eluted with a mobile phase consisting of methanol: water (15:85). Identification of radioactive metabolites eluting from the HPLC column was performed using HPLC, GC-MS, and chemical procedures. The method is suitable for the quantitative analysis of 14 C-DPH and its metabolites in biological samples.
Solid state structure and oxygen transport properties of copolyesters based on smectic poly(hexamethylene 4,4′-bibenzoate)

Abstract This study examined the solid state structure and oxygen barrier properties of copolyesters based on smectic poly(hexamethylene 4,4′-bibenzoate) (PHBB) and non-liquid crystalline poly(hexamethylene isophthalate) (PHI). The isophthalate content was varied from 10 to 75 mol%. Differential scanning calorimetry (DSC), wide angle X-ray diffraction (WAXD), dynamic mechanical thermal analysis (DMTA), and atomic force microscopy (AFM) were employed to characterize the polymers. The strong ordering tendency of 4,4′-bibenzoate was demonstrated by the persistence of ordered PHBB structures in copolymers with large amounts of the kinked isophthalate comonomer. Copolymers with up to 50 mol% isophthalate gave evidence of liquid crystalline (LC) character in the precursor melt. Copolymers with up to 75 mol% isophthalate crystallized in the PHBB α-crystal form with only small perturbations of the unit cell. The copolymers provided insight into the low gas permeability of LC polymers. Changes in both solubility and diffusivity contributed to the lower oxygen permeability of the smectic glass compared to the amorphous glass. Smaller free volume hole size of the smectic glass gave rise to lower oxygen solubility and contributed to lower diffusivity. The extended chain conformation in the smectic glass, which reduced the fraction of glycol units in gauche conformations, was a second factor that contributed to lower diffusivity.
Diminished striatal [123I]iodobenzovesamicol binding in idiopathic cervical dystonia

Striatal dysfunction is thought to underlie many dystonias. We used [(123)I]iodobenzovesamicol single-photon emission computed tomography imaging to determine the density of cholinergic terminals in the striatum and other brain regions in 13 subjects with idiopathic cervical dystonia. Striatal [(131)I]iodobenzovesamicol binding was reduced. These results support a role for striatal dysfunction in idiopathic dystonias and suggest diminished striatal cholinergic interneuron density in cervical dystonia.
Studies on the mechanism of the stimulation of tyrosine aminotransferase activity in vivo by pyrimidine analogs: The role of enzyme synthesis and degradation

Abstract The pyrimidine analogs, 5-fluoroorotate and 5-azacytidine, have been shown to stimulate the basal level as well as the cortisone, tryptophan, and casein hydrolysate-induced levels of the rat liver enzyme, tyrosine aminotransferase. This stimulation was most marked in the case of dietary and hormonal induction when the analog was given 4–6 hr prior to the administration of the inducer. When tryptophan induced tyrosine aminotransferase, maximal stimulation by the analog occurred if it were given 2 hr prior to the administration of the amino acid. The optimal stimulatory dose of 5-azacytidine was 5 mg/kg body weight whereas 5-fluoroorotate gave its highest stimulation at a dose of 60 mg/kg. Of several orotic acid analogs tested, only the chloro-analog had an effect similar to the fluoro-congener. Utilizing quantitative immunochemical precipitation and pulse labeling in vivo, it was demonstrated that the administration of 5-fluoroorotate or 5-azacytidine at doses of 60 and 5 mg per kg, respectively, while causing a stimulation in the basal level of tyrosine aminotransferase, did not result in any change in the rate of enzyme synthesis. Furthermore, after cortisone induction of the enzyme, the delayed administration of these analogs caused either a further stimulation in the level of the enzyme or the maintenance of a high level while the enzyme activity decayed in animals not given the analogs. The rates of synthesis either showed no change or a decrease while the amount of enzyme was increasing. Prelabeling of the enzyme in vivo after induction with cortisone and followed by the administration of 5-fluoroorotate resulted in a marked decrease in the t 1 2 of the decay rate of the enzyme measured either by loss of radioactivity or by loss of enzyme activity. These studies suggest that these analogs act in some manner to prevent enzyme turnover by an inhibition of enzyme degradation.
MDMS: Molecular Dynamics Meta-Simulator for evaluating exchange type sampling methods.

Abstract Replica exchange methods have become popular tools to explore conformational space for small proteins. For larger biological systems, even with enhanced sampling methods, exploring the free energy landscape remains computationally challenging. This problem has led to the development of many improved replica exchange methods. Unfortunately, testing these methods remains expensive. We propose a molecular dynamics meta-simulator (MDMS) based on transition state theory to simulate a replica exchange simulation, eliminating the need to run explicit dynamics between exchange attempts. MDMS simulations allow for rapid testing of new replica exchange based methods, greatly reducing the amount of time needed for new method development.
Lüttinger Liquid to Al’tshuler−Aronov Transition in Disordered, Many-Channel Carbon Nanotubes

We present a simple method to increase the conductance of individual template-grown carbon nanotubes contacted with platinum electrodes using a high-bias treatment process which decorates the nanotubes with Pt nanoclusters. The temperature dependence of conductance of the modified carbon nanotubes follows very closely a Luttinger-liquid to Al’tshuler−Aronov anomaly and reveals enhanced number of channels and decreased disorder-density compared to the pristine tubes. Low temperature magnetotransport shows evidence of Rashba spin−orbit coupling, usually absent in bare nanotubes, and a strong suppression of phase coherence at low electronic energies due to electron−electron interactions.
Aerological evidence of large‐scale mixing in the atmosphere

As a result of the general acceptance of air-mass analysis by American meteorologists, the number of aerological stations in the United States has been increased to such an extent that it is now frequently possible to prepare daily synoptic charts, not only for the sea-level but also for selected levels in the lower half of the troposphere. At present, this aerological material is being utilized primarily for the purpose of verifying the surface-map analyses, minor exceptions being the use of thermodynamic diagrams in the forecasting of thunder-storms and of ice-formation on aircraft. Our experience during the last few years indicates that two practically identical surfacemaps may be associated with widely different vertical structures; it should therefore be possibleto extract from the upper-air data information not implicitly contained in the surface-reports. Our present inability to do so is probably the result of unsatisfactory methods of representing t:ie state of the free atmosphere. The purpose of this preliminary report is to discuss briefly certain, studies now in progress at the Massachusetts Institute of Technology, which have as one of their aims the development of improved methods for the treatment of aerological data.
Assessing defect density and wear resistance of ultrathin diamond-like carbon films

Diamond-like carbon (DLC) films serve the dual purpose of protecting the magnetic underlayer from both slider contact and environmental corrosion in computer disk drives. Steadily increasing storage densities necessitate thinner and thinner protective films. Continuous, pinhole-free coverage of the magnetic medium is more difficult to achieve with thinner layers. Due to their sub-nanometer size, conventional techniques (SEM and AFM) are generally unable to detect pinholes. Therefore, we have utilized a novel pinhole-decoration technique (based on electrodeposition of Cu) to assess the coverage of very thin dual ion beam deposited nitrogen-doped DLC (N-DLC) films. The results of the decoration technique are compared with nanoscratch wear-resistance data. This combination of techniques demonstrates that, below 2 nm, the layer continuity and nanoscratch wear resistance of N-DLC films are severely compromised.
Bearing Witness: Rape, Female Resistance, Male Authority and the Problems of Gender Representation in Popular Indian Cinema:

Indian cinema in its preoccupation with rape shows a parallel between feminist resistance and nationalist resistance. While Mirch Masala (1985), set in pre-Independence rural India, is able to draw upon a mythology of nationalist resistance, which also, at the same time, 'sanctions and mediates the potentially subversive politics of female resistance', later films like Zakhmi Aurat (1988) and Damini (1993) qualify women's autonomous resistance by including male partners to witness, support and legitimise their actions. We conclude that in popular cinema 'the more radical the gesture of resistance, the more conservative the resolution'. All the same, as fanta sised reactions to rape enacted by women, they engage the politics of female resistance in ways that are relevant to our feminist understanding.
The primary etiology of the specific languagedisabilities

Summary A family tree covering four generations illustrates the familial natureof left-handedness and ambidexterity, bodily clumsiness, and the specific language disabilities. These conditions occur together in the individual and in his family tree sufficiently often to constitute a syndrome. The only factor that they appear to have in common is a slow tempo of neuromuscular maturation, which may be general or may be most conspicuous in certain skills. This slow maturation probably implies an equally slow tempo of myelination of motor and association nerve tracts. It is suggested that this inherited tendency to delayed neuromuscular maturation is the single factor from which all the various aspects of the syndrome may develop.
Regular and irregular human fetal respiratory movement

Fetal respiratory movements (FRM) were studied using abdominal strain gauges (tocodynamometers). The patterns of the FRM were evaluated during both active and quiet fetal time periods, which were determined by the fetal heart rate (FHR) and fetal body movement (FM). The FRM were classified into Regular and Irregular patterns based on neonatal respiratory criteria for sleep-state studies in the term infant. Evaluation of the breath-to-breath intervals (BBI) showed statistically significant respiratory differences during active and quiet fetal time periods. Irregular fetal respiratory movement patterns were noted during fetal active periods. It would appear that the correlation of regular fetal respiratory movement with fetal quiet periods in the term fetus adds additional evidence that a quiet sleep state may exist in the term fetus.
Linking Traits to Energetics and Population Dynamics to Predict Lizard Ranges in Changing Environments

Abstract: I present a dynamic bioenergetic model that couples individual energetics and population dynamics to predict current lizard ranges and those following climate warming. The model predictions are uniquely based on first principles of morphology, life history, and thermal physiology. I apply the model to five populations of a widespread North American lizard, Sceloporus undulatus, to examine how geographic variation in traits and life histories influences ranges. This geographic variation reflects the potential for species to adapt to environmental change. I then consider the range dynamics of the closely related Sceloporus graciosus. Comparing predicted ranges and actual current ranges reveals how dispersal limitations, species interactions, and habitat requirements influence the occupied portions of thermally suitable ranges. The dynamic model predicts individualistic responses to a uniform 3°C warming but a northward shift in the northern range boundary for all populations and species. In contra...
Numerical computation of two-LO SIS mixer gain and noise

The authors present numerical calculations of the gain and noise of a two-LO (local oscillator) mixer based on an ideal SIS (superconductor-insulator-superconductor) IV curve. They demonstrate the phase-sensitive response of the mixer with two-LO pumping and present calculations of the noise for various DC bias conditions and embedding impedances. Preliminary results indicate that for certain DC bias conditions and signal terminations, the noise added to a signal by the two-LO mixer operated in the single-sideband mode can be a factor of 25 less than that added by a conventional single-sideband single-LO mixer. >
Synergic extraction of zinc, cadmium and lead with hexafluoroacetylacetone and di-n-butylsulphoxide and tri-n-butyl phosphate, and the gas chromatography of the zinc adduct.

Abstract The synergic solvent extraction of zinc(II), cadmium(II), and lead(II) with 1,1,1,5,5,5-hexafluoro-2,4-pentanedione, H(HFA), and tri-n-butyl phosphate (TBP) or di-n-butylsulphoxide (DBSO) as neutral donors, into cyclohexane has been investigated. Quantitative extraction occurs at pH 4.5–6.0 in extraction times of 10–30 min, depending on the metal species. The optimum pH, equilibration time, stoichiometry and stability of the extracted species, as well as the effect of fluorinated β-diketone concentration, metal concentration and neutral donor concentration on the extraction are reported. The extracted species was found to be M(HFA)2.2DBSO or M(HFA)2.2TBP by mass-action studies. Thermogravimetric analysis of the complexes is reported. The gas chromatographic behaviour of the ternary complexes of the three metals has also been studied. A calibration plot of peak area vs. the amount of zinc injected was linear over the range 40–900 ng of zinc for the Zn(HFA)2. 2DBSO species; the cadmium and lead species apparently decomposed on the column and useful chromatographic peaks were not observed. The calibration plot for zinc was determined on the basis of the averages of 3–5 replicate determinations for 14 different concentrations over the range stated. The average relative standard deviation was 2.9%.
Thermal Image Analysis Techniques For Seam Tracking In Arc Welding

Implementation of robotics into welding is an important step toward higher productivity and better quality control of the fabrication process. However most robots currently perform welding in a "blind" fashion. In order to enhance the intelligence of the robots several sensing techniques such as laser stripping, through-the-arc sensing and infrared thermography have been investigated. Most of these sensing techniques are capable of monitoring only a single welding parameter. However infrared thermography has shown promise to detect several types of impending weld defects. 1,2 The results presented in this paper identify approaches to obtain quantitative relationships to monitor the torch position with respect to the seam of the plates being welded. The asymmetry of the thermal profiles caused by arc misalignment has been quantified into a torch seam error relationship. Two principal comparison techniques have been identified. Averaging methods have been implemented to reduce the noise level in the error signals.
Coupled relaxations in a blend of PMMA and a polycarbonate

Abstract Proton lineshape and proton spin-lattice relaxation, T1ρ, measurements were made on blends of bisphenol chloral polycarbonate and perdeutero poly(methyl methacrylate) (PMMA). The solution-cast blends are optically clear and display a single thermal glass transition temperature, Tg, as reported. The proton lineshape and proton relaxation data are used to follow the dynamics of the polycarbonate in the blend. The glass transition process is monitored by lineshape collapse as a function of temperature and the sub-glass transition process associated with π flips of the phenylene group is monitored by the proton T1ρ values as a function of temperature. The glass transition as viewed from the polycarbonate remains similar in character to the behaviour observed in pure polycarbonate. Below Tg, the lineshape consists of a broadened Pake doublet and above Tg a narrow Lorentzian grows in on top of the Pake pattern. The bimodal behaviour and the growth of the narrow line with temperature can be described by the Vogel-Tamman-Fulcher equation with T0 values which decrease with PMMA concentration. The proton T1ρ data show antiplasticization in the form of suppression of the π flip process as PMMA is added. In addition, a new minimum associated with the motion of the polycarbonate is observed at the temperature and time scale of the ester group rotation of the PMMA. This apparent coupling of the sub-Tg relaxation processes is related to the behaviour of polycarbonate upon addition of low-molecular-weight ester diluents. The level of antiplasticization and the amount of coupling is underestimated by a lattice model and an assumption of random mixing. On the very local scale of the π flip motion and at the higher concentrations of PMMA, there are apparently fewer PMMA-polycarbonate contacts than a random mixing assumption indicates.
HISTOCHEMICAL STUDIES OF THE PERIODONTAL LIGAMENT IN LATHYRITIC RATS.

Abstract The purpose of this histochemical study was to elucidate the nature of the chemical changes accompanying the altered morphology of the periodontal ligament in lathyritic rats. Weanling, male rats were divided into control and experimental groups, and fed Purina Fox Chow; 0.4 per cent beta-aminopropionitrile was added to the diet of the experimental animals. The rats were pair-fed. One control and one experimental group of rats were killed after 3, 7 and 14 days on their diets. Sections of the mandible were stained with the following methods: (a) haematoxylin and eosin, (b) Foot's silver stain, (c) van Gieson method, (d) periodic acid-Schiff method with and without prior hyaluronidase and amylase digestion and pyridine extraction and (e) metachromatic staining reaction, sulphation metachromasia method, and colloidal iron absorption method with and without prior hyaluronidase digestion. Examination of tissue sections showed in the periodontal ligament of the experimental animals the presence of fine, disoriented collagen fibres which failed to assemble and form bundles of fibres. These changes in the fibres were associated with changes in the ground substance. The area occupied by the ground substance was increased; in addition there was an increase in the concentration of available chemical groups of materials exhibiting staining characteristics of neutral polysaccharides. The role of the carbohydrate moiety on the stability of collagen is discussed.
Estrogen-induced proteins of human endometrium

Abstract Estrogen-induced protein(s) in human endometrium are described. Conjugated estrogens (Premarin) and 17β-estradiol were utilized for in vivo , in situ and in vitro induction protocols in women undergoing gynecologic surgery. Differential incorporations of radiolabelled aminoacids ([ 3 H] or [ 14 C] leucine), demonstrable by polyacrylamide disc gel electrophoresis, indicated the presence of rapidly synthesized cytoplasmic protein(s) in response to estrogen exposure. Actinomycin D prevented the induction when present in the in vitro incubations, suggesting that RNA synthesis is necessary for the protein(s) to appear. The full interaction between estrogens and the human endometrial cell deserves close attention in the light of a growing concern about the role of estrogens in the induction of endometrial neoplasia.
Membrane glycoprotein biosynthesis: changes in levels of glycosyl transferases in fibroblasts transformed by oncogenic viruses.

Fibroblasts transformed by oncogenic viruses were found to have greater enzymic activities of four membrane glycoprotein:glycosyl transferases on a cell or protein basis then two non-transformed fibroblastic lines. These enzymes are responsible for the synthesis of membrane glycoproteins; each of the four transferases studied, the polypeptide:N-acetylgalactosaminyl, glycoprotein:galactosyl, fetuin:fucosyl and PSM:fucosyl transferases, was more than twice as active in the transformed cell lines using both endogenous and added receptor. The most pronounced differences occurred with the doubly (SV-PY-3T3) transformed fibroblasts in all cases; with the N-acetylgalactosaminyl and galactosyl transferases the increase was 8–16 fold over the non-transformed cells. It was demonstrated that these results do not arise from a changed level of glycosidase activities.
Why Can't You See Me? The Invisibility of Homelessness

Cet article est le temoignage d'un ancien sans-abri qui decrit les conditions dans lesquelles la satisfaction de chaque besoin quotidien n'est pas garantie et peut constituer une veritable epreuve. Parmi ses souffrances, les consequences de l'indifference d'autrui (sentiment d'invisibilite) furent parmi les plus douloureuses. L'A. poursuit desormais un cursus de travailleur social et il plaide pour un autre regard sur la pauvrete, tant de la part de ses concitoyens que de la part des decideurs des politiques publiques
Back-Electron Transfer Suppresses the Periodic Length Dependence of DNA-Mediated Charge Transport across Adenine Tracts

DNA-mediated charge transport (CT) is exquisitely sensitive to the integrity of the bridging π-stack and is characterized by a shallow distance dependence. These properties are obscured by poor coupling between the donor/acceptor pair and the DNA bridge, or by convolution with other processes. Previously, we found a surprising periodic length dependence for the rate of DNA-mediated CT across adenine tracts monitored by 2-aminopurine fluorescence. Here we report a similar periodicity by monitoring N2-cyclopropylguanosine decomposition by rhodium and anthraquinone photooxidants. Furthermore, we find that this periodicity is attenuated by consequent back-electron transfer (BET), as observed by direct comparison between sequences that allow and suppress BET. Thus, the periodicity can be controlled by engineering the extent of BET across the bridge. The periodic length dependence is not consistent with a periodicity predicted by molecular wire theory but is consistent with a model where multiples of four to five base pairs form an ideal CT-active length of a bridging adenine domain.