Publications

Thin films of a molecularly imprinted sol-gel polymer with specific binding sites for parathion were developed. The films were cast on glass substrates and on glassy carbon electrodes and were used to detect parathion in aq. solns. Gas-phase binding measurements were performed on coated quartz crystal microbalance resonators. The binding of parathion to the imprinted films in the liq. phase was investigated by steady-state expts. with anal. by GC-FPD and cyclic voltammetry. The imprinted films showed high selectivity toward parathion in comparison to similar organophosphates. The binding was very sensitive to the type of functional monomer used for imprinting, and that rational design of the matrix components is an essential step in mol. imprinting. Specific binding in the gas phase proved to be less sensitive to the imprinting effect and exhibits relatively high nonspecific binding. The difference between mol. recognition in the gas- and liq.-phase imprinted polymer is discussed. [on SciFinder(R)]

Abstract Courts were commonly regarded as a neutral arena to settle disputes between rivals who cannot solve their differences through other means of dispute resolution. In recent years however, greater attention is drawn to the role played by courts within the political process itself. This article sets out to examine the role of public litigation in the Israeli High Court of Justice as a vehicle of political participation. We will argue that the Court has become an avenue for: a) participation in decision-making processes, b) communication with official authorities, and c) protestation against these very same authorities. [ABSTRACT FROM AUTHOR]Copyright of Conference Papers -- American Political Science Association is the property of American Political Science Association and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Although there is a general consensus that highly cationic peptides kill bacteria primarily by injuring their membranes, an additional hypothesis is proposed suggesting that a large variety of cationic peptides might also render bacteria non viable by activating their autolytic wall enzymes - muramidases (a "Trojan Horse" phenomenon), resulting in bacteriolysis. This group of cationic peptides includes: lysozyme, lactoferrin, neutrophil-derived permeability increasing peptides, defensins, elastase, cathepsin G, and secretory phopholipase A2. In this respect, cationic peptides mimic the bactericidal/bacteriolytic effects exerted by of beta-lactam antibiotics. Bacteriolysis results in a massive release of the pro-inflammatory cell-wall components, endotoxin (LPS), lipoteichoic acid (LTA) and peptidoglycan (PPG), which if not effectively controlled, can trigger the coagulation and complement cascades, the release from phagocytes of inflammatory cytokines, reactive oxygen and nitrogen species, and proteinases. Synergism (a "cross-talk") among such agonists released following bacteriolysis, is probably the main cause for septic shock and multiple organ failure. It is proposed that a use of bacteriolysis-inducing antibiotics should be avoided in bacteremic patients and particularly in those patients already suspected of developing shock symptoms as these might further enhance bacteriolysis and the release of LPS, LTA and PPG. Furthermore, in additonal to the supportive regimen exercised in intensive care settings, a use of non bacteriolysis-inducing antibiotics when combined with highly sulfated compounds (e.g. heparin, and other clinically certified polysufates) should be considered instead, as these might prevent the activation of the microbial own autolytic systems induced either by highly cationic peptides released by activated phagocytes or by the highly bacteriolytic beta-lactams. Polysulfates might also depress the deleterious effects of the complement cascade and the use of combinations among anti-oxidants ( N-acetyl cysteine), proteinase inhibitors and phospholipids might prove effective to depress the synergistic cytotoxic effects induced by inflammatory agonists. Also, a use of gamma globulin enriched either in anti-LPS or in anti-LTA activities might serve to prevent the binding of these toxins to receptors upon macrophage which upon activation generate inflammatory cytokines. Thus, a use of "cocktails" of anti-inflammatory agents might replace the unsuccessful use of single antagonists proven in scores of clinical trials of sepsis to by ineffective in prolonging the lives of patients. It is enigmatic why the concept, and the publications which support a role for cationic peptides also as potent inducers of bacteriolysis, an arch evil and a deleterious phenomenon which undoubtedly plays a pivotal role in the pathophysiology of post-infectious sequelae, has been consistently disregarded.

Off-centered top-seeded solution growth (TSSG) method is demonstrated as an effective and simple way to generate controlled composition modulation in potassium lithium tantalate niobate (KLTN) single crystals. The changes in concentration were measured by differential interference contrast (DIC) microscopy. Large length with periodic modulations ranging from 1 to 5 mum in period was grown along a KLTN sample with period dispersion lower than 2%. (C) 2004 Elsevier B.V. All rights reserved.

Changes in circadian rhythms of behavior are related to age-based division of labor in honey bee colonies. The expression of the clock gene period (per) in the bee brain is associated with age-related changes in circadian rhythms of behavior, but previous efforts to firmly associate per brain expression with division of labor or age have produced variable results. We explored whether this variability was due to differences in light and flight experience, which vary with division of labor, or differences in colony environment, which are known to affect honey bee behavioral development. Our results support the hypothesis that per mRNA expression in the bee brain is developmentally regulated. One-day-old bees had the lowest levels of expression and rarely showed evidence of diurnal fluctuation, while foragers and forager-age bees (>21 days of age) always had high levels of brain per and strong and consistent diurnal patterns. Results from laboratory and field experiments do not support the hypothesis that light, flight experience, and colony type influence per expression. Our results suggest that the rate of developmental elevation in per expression is influenced by factors other than the ones studied in our experiments, and that young bees are more sensitive to these factors than foragers. (C) 2004 Elsevier Ltd. All rights reserved.

Photodissociation experiments were carried out at 193 nm for single HCl molecules which are adsorbed on the surface. of large Ar-n clusters and small (HCl)(m) complexes which are embedded in the interior of these clusters. For the surface case the size dependence is measured for the average sizes =140-1000. No cage exit events are observed in, agreement with the substitutional position, of the molecule deeply buried in. the outermost shell. This result is confirmed by a molecular dynamics simulation of the pickup process under realistic conditions concerning the experiment and the interaction potentials. The calculations of the dissociation process employ the surface hopping model., For the embedded case the average sizes covered are =3 and 6 and =8-248. The kinetic energy of the H atom fragments is measured exhibiting peaks at zero and around 2.0 eV which mark completely caged and unperturbed fragments, respectively. The ratio of theses peaks strongly depends on the cluster size and agrees well with theoretical predictions for one and two closed icosahedral shells, in which the nonadiabatic coupling of all states was accounted for. (C) 2004 American Institute of Physics.

Single photon ionization dynamics of glycine is studied by classical trajectory simulations using the semiempirical PM3 potential surface in ``on the fly'' calculations. The glycine conformer is assumed to be in the vibrational ground state prior to ionization. Initial conditions for the trajectories are weighted according to the Wigner distribution function computed for that state. Vertical ionization in the spirit of the classical Franck-Condon principle is assumed. The main findings are as follows: (1) The photoionization triggers a fast internal rotation about the C-C bond, with the NH(2) group rotating in one direction, and the COOH group rotating in the opposite direction. For the trajectories where the fast rotation occurs, it persists till the end of the simulation (10 ps). The yield for this process is about 6%, suggesting it may be experimentally observable. (2) For many of the trajectories, the photoproduced glycine ion exhibits ``hops'' between two conformer structures. The rates computed from the dynamics for these conformational transitions differ considerably from RRK predictions. (3) Different behavior of vibrational energy flow is found for different types of modes. There is no significant approach to statistical distribution of the energy throughout the first 10 picoseconds. (4) The preferred dissociation channel is the C-C bond cleavage. Indeed, fragmentation is observed for a few trajectories, one of them shows H atom hopping from the amino group to the carbonyl group prior to dissociation. Another trajectory shows only this hydrogen transfer and the transfer back. Possible experimental implications of some of the findings are briefly discussed.

Mycoplasma penetrans invades HeLa cells and survives within them for prolonged periods of time. The intracellular distribution of M. penetrans within HeLa cells was studied utilizing the acidotropic dye LysoTracker (green), which permeates cell membranes and upon protonation remains trapped in acidic compartments. The excitation and emission spectra of the green LysoTracker are suitable for colocalization studies with rabbit anti- M. penetrans antibodies and red Cy5 goat anti-rabbit IgG. The images collected by confocal laser scanning microscopy revealed that in the infected HeLa cells almost all Cy5 fluorescent foci (red) were located within the LysoTrack-labelled intracellular compartments, apparently endosomes. Viable mycoplasmas were detected within endosomes for prolonged periods of time, apparently due to a potent antioxidant activity detected in M. penetrans.

BACKGROUND: Previous studies have shown that PADMA-28, a multicomponent, traditional Tibetan herbal plant preparation possesses a variety of beneficial effects on several experimental models of inflammatory and immune processes, including autoimmune diabetes and autoimmune encephalomyelitis. In humans, PADMA-28 attenuated the symptoms associated with intermittent claudications in atherosclerotic patients. OBJECTIVE: To assess the effect of PADMA 28 on the immune system, e.g. cytokine (interleukins) production. DESIGN: Cytokine production by human blood monocytes (derived from 12 healthy donors) stimulated in vitro, either by endotoxin (LPS) from Salmonella typhi or by lipoteichoic acid (LTA) from group A Streptococci was modulated by PADMA-28. RESULTS: The present study showed that an aqueous extract of PADMA-28 strongly decreased the production of the inflammatory cytokines IL-1beta, IL-6, IL-8 and TNF-alpha, and more moderately, also decreased the anti-inflammatory cytokine IL-10 induced by LPS. However, the LTA - induced IL-10 production was [not significantly] increased by the low dose PADMA-28, while not effected at all by the higher dose of PADMA-28. CONCLUSIONS: The data from these finding suggest a possible clinical efficacy of PADMA-28 either in autoimmune and in inflammatory conditions or in post-inflammatory sequelae, as previously shown in in vivo and human studies, probably by decreasing inflammatory cytokines.

It is known that many agents influence the capacity of cells to produce reactive oxygen species. However, assaying these agents, both those that stimulate and those that inhibit reactive oxygen production, can be complicated and time consuming. Here, a method is described in which two different cocktails are employed to stimulate luminol-dependent chemiluminescence (LDCL). These cocktails are comprised of luminol, with either sodium selenite [IV] (SEL) or tellurite [IV] (TEL) (where IV and VI refer to the 4+ or 6+ oxidation state of selenium or tellurium salts, respectively), morpholinosidonimine (SIN-1), serum albumin and Co(2+), called the SIN-1a (with selenite) and SIN1b (with tellurite) cocktails, respectively; or luminol with glucose oxidase (GO), sodium selenite [IV] and Co(2+), called the GO cocktail. The cocktails functioned best in Hank's balanced salt solution (HBSS) containing 1% glucose at pH 7.4, incubated at approximately 22 degrees C. Within 30-60 s there was a burst of luminescence, which lasted for 7-10 min. In 100% ethanol, the SIN-1 cocktails also generated LDCL to 70% of that produced in HBSS. Neither selenite [VI], seleno-cystine, seleno-methionine, nor the selenium-containing drug, ebselen, could replace SEL. Moreover, the effects of the NO-donor, SIN-1, could not be replicated by the oxyradical generators, xanthine-xanthine oxidase or hypochlorous acid. Only low levels of luminescence were generated by combinations of the peroxyl radical generator, 2,2'-azobis-2-amidinopropane dihydrochloride (AAPH) with either SEL or TEL. It is suggested that light emission induced by the SIN1 cocktail results from the oxidation of SEL [IV] to the [VI] state, possibly due to the generation of mixtures of superoxide, peroxide, peroxynitrite and also of unidentified oxidant species, catalyzed by CoCo(2+). However, the involvement of hydroxyl radicals in LDCL could not be confirmed by use of either dimethyl thiourea or by electron spin resonance (ESR). LDCL induced by the two cocktails is strongly reduced by phosphates, EDTA, deferoxamine, CuCo(2+), MnCo(2+), as well as by the "classical" antioxidants superoxide dismutase (SOD), ascorbate, vitamin E, uric acid or thiols. It is suggested that these chemiluminescence cocktail systems can be used to determine the total anti-oxidant capacities of biological fluids and commercially available anti-oxidants.

Using two luminescence-inducing cocktails, two distinct patterns of inhibition of light by different anti-oxidants have been identified, comprising Group A, in which a complete inhibition of light emission which is then followed by re-emergence of light, forming apparent S-shaped curves or similar shapes. This light pattern is induced by the "classical" anti-oxidants, ascorbate, vitamin E, uric acid, thiols, deferoxamine, as well as by anti-oxidant agents present in plasma, saliva, urine and in extracts derived from black coffee, and Group B, in which a gradually emerging "mound"-shaped pattern of light was seen with extracts from the Tibetan plant mixture PADMA-28, elderberry (Sambucol), grape seeds, green and black teas, apple, parsimony, red wines, edible oils and SOD. While the results with the Group A agents point to the presence of probably a single, major, anti-oxidants relatively sensitive to oxidation, Group B agents probably include a mixture of anti-oxidants which are more resistant to oxidation. It was also shown that agents from Group B could protect agents from Group A against consumption by the oxidants generated by the cocktails. It is proposed that these simple to use cocktails which probably generate a multiplicity of oxidants mimicking those generated by activated phagocytes, can rapidly assess the total anti-oxidant capacities (TAOC) in body fluids derived from patients suffering of excessive oxidative stress. Also, this technique may be useful in determining the content of dietary anti-oxidants recommended as supplements to enhance the resistance against excessive oxidation of lipids.

The growth factors basic fibroblast growth factor (bFGF) and insulin-like growth factor 1 (IGF-I) have been implicated in the pathophysiology of atherosclerosis and restenosis. The Tibetan herbal preparation PADMA-28 (a mixture of 22 plants which is used as an anti-atherosclerosis agent) was tested for its ability to inhibit the mitogenic activity of bFGF and IGF-I, growth factors involved in restenosis, atherosclerosis and tumour progression. DNA synthesis and proliferation of vascular smooth muscle cells, in response to serum bFGF, thrombin, or combinations thereof, were abrogated in the presence of microgram amounts of both the aqueous and organic, partially purified, extracts of PADMA-28. These fractions also inhibited IGF-I-mediated proliferation, migration and invasion of tumour cells responsive to IGF-I. The inhibition by PADMA 28 was reversible upon removal of the PADMA extracts, indicating that the effects were not related to cell toxicity. These and other properties (i.e., anti-oxidant activity) of PADMA-28 may be responsible for its beneficial effect as an anti-atherosclerotic agent, suggesting that this herbal preparation may have potential applications in the prevention of intimal hyperplasia and arterial stenosis secondary to coronary angioplasty and bypass surgery, as well as in the prevention and treatment of other vascular diseases and tumour growth and metastasis.

The electrochem. formation and characterization of decanoic, myristic, palmitic, and stearic acid self-assembled monolayers on a native oxide surface of 316L stainless steel were studied. This work describes a new approach to surface modification of stainless steel in which the self-assembly of n-alkanoic acids is facilitated by applying a potential to the stainless steel in an org. electrolyte soln. While decanoic acid forms a disorganized monolayer of sweeping the potential in an MeCN soln. contg. 0.1 mM of the resp. acid, longer acids, i.e., myristic and palmitic acids, form highly ordered closed-packed monolayers. This electrochem. approach results in highly reproducible monolayers that are deposited within a shorter time than the traditional assembly process. The monolayers were characterized by cyclic voltammetry, double-layer capacity (a.c. voltammetry), contact angle measurements, XPS, and external reflection-absorption FTIR spectroscopy. The use and implications of this modification technique are discussed. [on SciFinder(R)]

The electrochemical formation and characterization of decanoic, myristic, palmitic, and stearic acid self-assembled monolayers on a native oxide surface of 316L stainless steel have been studied. This work describes a new approach to surface modification of stainless steel in which the self-assembly of n-alkanoic acids is facilitated by applying a potential to the stainless steel in an organic electrolyte solution. While decanoic acid forms a disorganized monolayer as a result of sweeping the potential in an acetonitrile solution containing 0.1 mM of the respective acid, longer acids, that is, myristic and palmitic acids, form highly ordered closed-packed monolayers. This electrochemical approach results in highly reproducible monolayers that are deposited within a shorter time than the traditional assembly process. The monolayers were characterized by cyclic voltammetry, double-layer capacity (ac voltammetry), contact angle measurements, X-ray photoelectron spectroscopy, and external reflection-absorption Fourier transform infrared spectroscopy. The utilization and implications of this modification technique are discussed.[on SciFinder (R)]

Resistance degradation in potassium lithium tantalate niobate (KLTN) doped with iron and titanium was measured in a single sample containing various concentrations of interstitial hydrogen. In this crystal the degradation arose from the migration of interstitial hydrogen and not oxygen vacancies, as reported in previous research. Interstitial hydrogen and oxygen vacancy defects both arise to compensate the valence shortfall of the substitutional iron impurities and the thermodynamic balance between the two compensation mechanisms can be controlled using reaction chemistry techniques. Through appropriate annealing treatments a single crystal of KLTN was prepared in three states: hydrogen-rich oxidized, hydrogen-poor reduced, and hydrogen-rich reduced. The characteristic degradation times for the three cases were 29, 2710, and 26 min, respectively. The degradation rate is correlated with hydrogen concentration and not oxidation state of the crystal. Infrared absorption from near the two electrodes of the hydrogen-rich reduced crystal after degradation confirmed polarization of the hydrogen concentration. Electrocoloration was also found to correlate with hydrogen-it was observed in both hydrogen-rich states, but was absent from the hydrogen-poor crystal. (C) 2004 American Institute of Physics.

The article focuses on exposure of 54 members of the Israeli Knesset, competing for media coverage. Tangibly, political power provides legislators with the ability to create newsworthy events, access to important and interesting information, and easy access to reporters, who routinely cover the offices the powerful legislators hold. Other variables that have been linked to leaders' publicity can be categorized under the heading of "media skills." The studies demonstrate that media coverage of legislators is influenced by more "macro" variables, such as the political and media cultures in which the competition over publicity is taking place and changes in the political environment.

This study proposes a number of theoretical and methodological innovations in an attempt to better understand how legislators compete for media coverage. We make a distinction between those variables that determine the potential newsworthiness of a legislature (production assets) and those that are related to the political and media environment in which the legislators operate (news opportunities). We then put forth five hypotheses and test them by examining the political standing, charismatic communication skills, and radio exposure of 54 members of the Israeli Knesset. The results confirm that political standing and charismatic communication skills are important predictors of media exposure and that the relative importance of these factors changes during different political seasons.