Meteorological radar is a remote sensing system that provides rainfall estimations at high spatial and temporal resolutions. The radar-based rainfall intensities (R) are calculated from the observed radar reflectivities (Z). Often, rain gauge rainfall observations are used in combination with the radar data to find the optimal parameters in the Z–R transformation equation. The scale dependency of the power-law Z–R parameters when estimated from radar reflectivity and rain gauge intensity data is explored herein. The multiplicative (a) and exponent (b) parameters are said to be “scale dependent” if applying the observed and calculated rainfall intensities to objective function at different scale results in different “optimal” parameters. Radar and gauge data were analyzed from convective storms over a midsize, semiarid, and well-equipped watershed. Using the root-mean-square difference (rmsd) objective function, a significant scale dependency was observed. Increased time- and space scales resulted in a considerable increase of the a parameter and decrease of the b parameter. Two sources of uncertainties related to scale dependency were examined: 1) observational uncertainties, which were studied both experimentally and with simplified models that allow representation of observation errors; and 2) model uncertainties. It was found that observational errors are mainly (but not only) associated with positive bias of the b parameter that is reduced with integration, at least for small scales. Model errors also result in scale dependency, but the trend is less systematic, as in the case of observational errors. It is concluded that identification of optimal scale for Z–R relationship determination requires further knowledge of reflectivity and rain-intensity error structure.
This article explores the ethical dimensions of computer‐mediated communication held in chatrooms. The philosophical underpinnings refer to the work of Martin Buber and Emmanuel Levinas, specifically to concepts relating to the ethics of Other‐oriented communication. The main argument is that this medium presents serious difficulty for Other‐oriented communication due to the potential for control over online interaction. This control is manifested in three ways: the ability to control online presence of Self and Other, the ability to manage exposure and vulnerability and thereby suspend surprise, and the means by which text‐based communication provides a sense of a separate‐space‐shared‐time. Based on this analysis, two tactics are suggested by which one might be able to resist control and allow for a more Other‐oriented interaction.
Ethosomes are noninvasive delivery carriers that enable drugs to reach the deep skin layers and/or the systemic circulation. Although ethosomal systems are conceptually sophisticated, they are characterized by simplicity in their preparation, safety, and efficacy–a combination that can highly expand their application. Ethosomes are soft, malleable vesicles tailored for enhanced delivery of active agents. This article reviews work carried out in vitro, in vivo, in animal models, and in humans with various ethosomal systems incorporating a wide range of drugs. Because of their unique structure, ethosomes are able to encapsulate and deliver through the skin highly lipophilic molecules such as cannabinoids, testosterone, and minoxidil, as well as cationic drugs such as propranolol and trihexyphenidil. Results obtained in a double-blind two-armed randomized clinical study showed that treatment with the ethosomal acyclovir formulation significantly improved all the evaluated parameters. Preliminary studies with plasmids and insulin revealed that the ethosomal carrier may be used for enhanced delivery of these agents. In further work, the ethosomal technology was broadened to introduce agents into cultured cells and microorganisms. Enhanced delivery of bioactive molecules through the skin and cellular membranes by means of an ethosomal carrier opens numerous challenges and opportunities for the research and future development of novel improved therapies.
The primary goal of this paper is to investigate whether participation in terrorist activity can be linked to ignorance (measured through schooling) or to economic desperation (measured through poverty on the individual’s level and various economic indicators on the societal level) using newly culled data of Hamas and Palestinian Islamic Jihad (PIJ) terrorist cells. This paper performs a statistical analysis of the determinants of participation in Hamas and PIJ terrorist activities in Israel from the late 1980’s to the present, as well as a time series analysis of terrorist attacks in Israel with relation to economic conditions. The resulting evidence on the individual level suggests that both higher standards of living and higher levels of education are positively associated with participation in Hamas or PIJ. With regard to the societal economic condition, no sustainable link between terrorism and poverty and education could be found, which I interpret to mean that there is either no link or a very weak indirect link. Special attention is given to the suicide bomber phenomenon, and the analysis of the determinants of becoming a suicide bomber provides additional intriguing findings. In contrast with the “classic” characteristics of a suicidal individual (Hamermesh and Soss, 1974), suicide bombers tend to be of higher economic status and higher educational attainment than their counterparts in the population. Suicide bombers, however, come from lower socioeconomic groups when compared to other, non-suicidal, terrorists.
It has been shown (Hart [2]) that the backward induction (or subgame-perfect) equilibrium of a perfect information game is the unique stable outcome for dynamic models consisting of selection and mutation, when the mutation rate is low and the populations are large, under the assumption that the expected number of mutations per generation is bounded away from zero.Here it is shown that one can dispense with this last condition. In particular, it follows that the backward induction equilibrium is evolutionarily stable for large populations.
Paclitaxel is a potent chemotherapeutic agent currently administered intravenously in polyoxyethylated castor oil (Cremophor EL) and dehydrated ethanol (1:1) for the treatment of solid tumors. The objective of this work was to develop a novel self-emulsifying drug delivery system (SEDDS) devoid of cremophor for the i.v./oral delivery of paclitaxel and to investigate the in vitro cytotoxicity of the combined excipients. The SEDDS formulations were characterized in terms of droplet size using a ternary phase diagram. The Caco-2 cell line was used to monitor the cytotoxicity of the excipients. Cell viability was determined colorimetrically at 570 nm utilizing the MTT assay. The distribution of the formulations on the phase diagram indicated the presence of macroemulsions ( approximately 1 microm), submicron emulsions (50-200 nm), and microemulsions (below 10 nm). An increase in the sodium deoxycholate excipient content led to an increase in physical stability but caused more chemical degradation of the drug and more cytotoxicity. The drug in the novel SEDDS was chemically stable for at least 1 year when kept as a two-part formulation. The drug loading was increased by approximately fivefold compared to the marketed i.v. formulation; the excipients presented a significantly reduced cytotoxicity and led to a stable microemulsion.
The inoculation of 2000 colony-forming units of Corynebacterium pseudotuberculosis into one teat canal of each of three cows resulted in severe, chronic, pyogranulomatous mastitis. Within three days the cows had a reduced haematocrit, haemoglobin concentration and red cell count. The anaemia was initially normocytic, normochromic and non-regenerative, and was associated with a brief peak of neutrophilia; a regenerative response became evident two to three weeks later. Clinical signs of mastitis appeared seven to 14 days after the inoculation, with a peak of high fever, more severe anaemia, a second peak of neutrophilia and the complete cessation of milk production from all quarters; extensive and severe pyogranulomatous mastitis developed in the inoculated quarters. No other lesions were detected postmortem, and C pseudotuberculosis was cultured from the affected quarters but not from the supramammary lymph nodes and viscera.
Calmodulin (CaM) is a second messenger protein that has evolved to bind tightly to a variety of targets and, as such, exhibits low binding specificity. We redesigned CaM by using a computational protein design algorithm to improve its binding specificity for one of its targets, smooth muscle myosin light chain kinase (smMLCK). Residues in or near the CaM/smMLCK binding interface were optimized; CaM interactions with alternative targets were not directly considered in the optimization. The predicted CaM sequences were constructed and tested for binding to a set of eight targets including smMLCK. The best CaM variant, obtained from a calculation that emphasized intermolecular interactions, showed up to a 155-fold increase in binding specificity. The increase in binding specificity was not due to improved binding to smMLCK, but due to decreased binding to the alternative targets. This finding is consistent with the fact that the sequence of wild-type CaM is nearly optimal for interactions with numerous targets.
The paper examines Joyce’s rethinking of inter-subjective space, focusing on a series of syntactic and metaphorical transactions constitutive of the Wake’s transgressive “langscape.” These transactions may be seen to correlate with the Wake’s thematization of mourning, and with the processes of inclusion, exclusion, and oral assimilation which regulate the constitution and preservation of subjective identity in the work of mourning. The paper attempts to account for these processes in terms of Abraham and Torok’s theories of incorporation and endocryptic identification. It adopts the notion of cryptic mourning as a theoretical framework within which to interpret the figure of the “fadograph” in Joyce as an image of radical and originary forgetting. Such an image – the negative of a mnemonic imprint – is seen to exemplify the possibility of including an unnameable or unimaginable place, secret and radically exterior to subjective memory or discourse, yet contrasted, in the Wake, with overt investment in a subjective and all-encompassing “here.”
Ruben Borg is Senior Lecturer in English literature at the Hebrew University of Jerusalem. His articles on Modernism have appeared in numerous journals, including Poetics Today, Modern Fiction Studies, Narrative andJournal of Modern Literature. Since 2003 he has served as associate editor of Partial Answers: Journal of Literature and the History of Ideas. He is the author of The Measureless Time of Joyce, Deleuze and Derrida (2007) and of Fantasies of Self-Mourning: Modernism, the Posthuman and the Finite (2019).
This essay is an attempt to apply some of the notions of ecology to the imagined worlds of Dostoevsky and Tolstoy. The premise is that each writer’s choice of physical settings has an important effect on his less tangible themes and concepts. The effects examined in this essay are not primarily social and conventional (systems of meaning), but rather quasi-physical. Tolstoy tends to set his stories along horizontal (though often somewhat irregular) planes, whereas Dostoevsky relies more on vertical planes (walls). These tendencies are reversed in scenes with a strong religious component, as if the authors required a foreign spatial orientation to convey otherworldly themes.
June 2003: Born in Tucson, Arizona, Tim Langen is Co-editor of Eight Twentieth-Century Russian Plays; author of The Stony Dance: Unity and Gesture in Andrey Bely's "Petersburg" (forthcoming). Current fields of interest: Russian literary and intellectual history.
Foraging bees spend less time flying between flowers of the same species than when flying between individuals of different species. This time saving has been suggested as a possible advantage of flower-constant foraging. We hypothesized that the time required to switch flower type increases if (a) such switches are infrequent and (b) the bees need to decide whether to switch or not. Laboratory reared bumblebees were taught to forage on artificial feeders that were identical in morphology and reward schedule, but were marked by either a blue or a yellow landing surface. In the first two experiments bees foraged alternatively between two feeders. The landing surface was manipulated to coerce the bees to perform either a color-constant or a color-shift flight movement. In Experiment 1 we switched the landing surfaces every 2-3 visits, while in Experiment 2 the bees performed 6-7 color-constant flights before having to perform a color-shift flight. In the third experiment, the bees were presented with binary choices and had to decide to make a color-constant or a color-shift flight. When feeder colors were changed frequently (Experiment 1), we detected no difference between color-constant and color-shift inter-visit times. When bees were repeatedly exposed to one color (Experiment 2), color shifts required a significantly longer time than color-constant flights. When allowed to choose (Experiment 3), bees performed more color-constant flights than color-shift flights. Inter-visit times were similar for color-constant and color-shift flights in this experiment. Overall flight times were slightly but non-significantly longer than in experiments 1 and 2. The results suggest that bees indeed save flight time though flower-constant foraging. However, this time saving is small ( 1 s / flower visit), and appears only when switches between flower types are infrequent. Additional selective advantages likely favor flower-constant foraging.
Like most low molecular weight drugs, carboplatin has a short blood circulation time, which reduces tumor uptake and intracellular DNA binding. Drugs conjugated to PEG carriers benefit from prolonged blood circulation, but suffer from reduced cell permeability. In this work we attempted to develop long-circulating PEGylated carboplatin analogues with improved cell permeation abilities, by conjugating the platinum moiety to folate-targeted PEG carriers capable of utilizing the folate receptor-mediated endocytosis (FRME). Two bifunctional FA-PEG conjugates, FA-PEG-Pt and FA-PEG-FITC, were prepared, and their cell uptake, DNA binding, and cytotoxicity were studied by fluorescent microscopy, FACS, and platinum analysis. Folate-targeted PEG conjugates enter the cells efficiently by the FRME pathway but form relatively few DNA adducts and have higher IC(50) values than carboplatin and their nontargeted analogues. Nontargeted PEG-Pt conjugates have a lower cellular uptake but produce higher levels of DNA binding and improved cytotoxicity. Carboplatin, used as a control, has the fastest cellular uptake, but after 16 h of postincubation a large percentage of the drug is excreted from the cells. The findings of this study suggest that folate-targeted conjugates such as FA-PEG-Pt, may not be an optimal prodrug for the carboplatin family compounds, because the conjugates or the active moieties are neutralized or blocked during the FRME process and do not manage to effectively reach the nuclear DNA.
An interfacial Maillard reaction between furfural and cysteine in two different food-grade nano-sized self-assembled solns. with two oppositely curved interfaces (W/O and O/W microemulsions) have been studied and compared. These microemulsions are selective microreactors strongly enhancing the generation of sulfur-contg. flavors. The Maillard reactions occur at lower temps. than in water and are much faster. The interfaces of both W/O and O/W microemulsions are capable of enhancing the Maillard reactions in which the selectivity and reactivity are controlled by the compn. of the interface and its curvature. In the W/O microemulsions the Maillard reaction was controlled and enhanced by the interfacial concn. of a co-emulsifier such as butanol and are restricted by the concn. of the core water reservoir. On the other hand, in the O/W microemulsions, where water is the continuous phase, the reaction rates are enhanced by increase in the water content and the microemulsion curvature. The Maillard product internal compn. (regioselectivity and type of products) is dictated by temp., time, pH and mainly by the nature of the interface, and by the surfactant nature and its interfacial compn. [on SciFinder(R)]
