Tubulin polyglycylation in Platyhelminthes: diversity among stable microtubule networks and very late occurrence during spermiogenesis

The distribution of glycylated tubulin has been analyzed in different populations of stable microtubules in a digenean flatworm, Echinostoma caproni (Platyhelminthes). Two cellular types, spermatozoa and ciliated excretory cells, have been analyzed by means of immunofluorescence, immunogold, and immunoblotting techniques using two monoclonal antibodies (mAbs), AXO 49, and TAP 952, specifically directed against differently glycylated isoforms of tubulin. The presence of glycylated tubulin in the two cell types was shown. However, the differential reactivities of TAP 952 and AXO 49 mAbs with the two axoneme types suggest a difference in their glycylation level. In addition, within a single cell, the spermatozoon, cortical microtubules underlying the flagellar membrane, and axonemal microtubules were shown to comprise different tubulin isoforms, the latter ones only being labelled with one of the antiglycylated tubulin mAbs, TAP 952. Similarly, the antiacetylated (6-11B-1) and polyglutamylated (GT335) tubulin mAbs decorated the two types of axonemal microtubules, but not the cortical ones. From these data, a subcellular sorting of posttranslationally modified tubulin isoforms within spermatozoa, on the one hand, and a cellular sorting of glycylated isoforms inside the whole organism, on the other hand, is demonstrated in the flatworm E. caproni. Last, a sequential occurrence of tubulin posttranslational modifications was observed in the course of spermiogenesis. Acetylation appears first, followed shortly by glutamylation; glycylation takes place at the extreme end of spermiogenesis and, specifically, in a proximo-distal process. Thus in agreement with, and extending other studies [Bré et al., 1996], glycylation appears to close the sequence of posttranslational events occurring in axonemal microtubules during spermiogenesis.     

Differential hemispheric processing of faces: Methodological considerations and reinterpretation.

Examines the procedures and stimuli (physiognomies) used in lateralized face recognition experiments with normal Ss, as well as in related perceptual and identification experiments. Results reveal that in general a left visual field (right hemisphere) advantage is obtained when: (a) stimulus information is degraded; (b) faces to be compared are highly discriminable; (c) set of unfamiliar faces is used; and (d) task requirements allow a lax criterion of recognition. These conditions seem to make holistic processing adequate for the task; if the conditions require analytic judgments, then a right visual field (left hemisphere) advantage may be obtained. Thus, no hemifield has an inherent or absolute advantage and these procedural conditions may critically determine what hemifield advantage is observed in any given experiment with faces (or other types of stimuli). Apparently, both hemispheres may contribute to the processing of faces but their contributions vary as a function of task demands. A right hemisphere advantage may reflect an enhanced role of the processes of configuration, completion, categorization, or set. A left hemisphere advantage need not involve the language function but it may reflect a genuine visuospatial contribution. (60 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Adaptive hypertext navigation based on user goals and context

Hypertext systems allow flexible access to topics of information, but this flexibility has disadvantages. Users often become lost or overwhelmed by choices. An adaptive hypertext system can overcome these disadvantages by recommending information to users based on their specific information needs and preferences. Simple associative matrices provide an effective way of capturing these user preferences. Because the matrices are easily updated, they support the kind of dynamic learning required in an adaptive system.HYPERFLEX, a prototype of an adaptive hypertext system that learns, is described. Informal studies with HYPERFLEX clarify the circumstances under which adaptive systems are likely to be useful, and suggest that HYPERFLEX can reduce time spent searching for information by up to 40%. Moreover, these benefits can be obtained with relatively little effort on the part of hypertext authors or users.The simple models underlying HYPERFLEX's performance may offer a general and useful alternative to more sophisticated modelling techniques. Conditions under which these models, and similar adaptation techniques, might be most useful are discussed.     

Image generation and processing of generated images in the cerebral hemispheres.

Recent computational models describing the contribution of the cerebral hemispheres to visual imagery have suggested an exclusive capacity of the left hemisphere to generate multipart images. A brief review of relevant findings indicates that the evidence presented in support of this suggestion is not entirely compelling; this prompted a reexamination of this issue in a lateral tachistoscopic study on normal adults. Sixteen subjects participated in two experiments in which they had to decide whether or not a lowercase letter contained a segment extending above or below the main body of the letter. This decision was made directly on lowercase letters in one experiment (perceptual task) and on their generated images in the other experiment (imagery task). The quality of the letters (clear or blurred) and the retinal eccentricity of stimulus presentation (small or large) were orthogonally manipulated. The perceptual task yielded no main effect of visual field but a significant interaction of visual field and letter quality. By contrast, the imagery task resulted in a left visual-field superiority but no interaction involving the visual fields—a departure from predictions based on current models of visual imagery. In addition, the pattern of results in the imagery task corresponded to that obtained with blurred letters in the perceptual task, suggesting limitations in spatial resolution of visual images. Implications of these results for models of cerebral lateralization and visual imagery are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Supporting geographically-aware web document foraging and sensemaking

This paper reports on the development and application of strategies and tools for geographic information seeking and knowledge building that leverages unstructured text resources found on the web. Geographic knowledge building from unstructured web sources starts with web document foraging during which the quantity, scope and diversity of web-based information create incredible cognitive burdens on an analyst’s or researcher’s ability to judge information relevancy. Determining information relevancy is ultimately a process of sensemaking. In this paper, we present our research on visually supporting web document foraging and sensemaking. In particular, we present the Sense-of-Place (SensePlace) analytic environment. The scientific goal of SensePlace is to visually and computationally support analyst sensemaking with text artifacts that have potential place, time, and thematic relevance to an analytical problem through identification and visual highlighting of named entities (people, places, times, and organizations) in documents, automated inference to determine document relevance using stored knowledge, and a visual interface with coupled geographic map, timeline, and concept graph displays that are used to contextualize the contexts of potentially relevant documents. We present the results of a case study analysis using SensePlace to uncover potential population migration, geopolitical, and other infectious disease dynamics drivers for measles and other epidemics in Niger. Our analysis allowed us to demonstrate how our approach can support analysis of complex situations along (a) multi-scale geographic dimensions (i.e., vaccine coverage areas), (b) temporal dimensions (i.e., seasonal population movement and migrations), and (c) diverse thematic dimensions (effects of political upheaval, food security, transient movement, etc.).     

Synthesis and Assembly of Click‐Nucleic‐Acid‐Containing PEG–PLGA Nanoparticles for DNA Delivery

Co‐delivery of both chemotherapy drugs and siRNA from a single delivery vehicle can have a significant impact on cancer therapy due to the potential for overcoming issues such as drug resistance. However, the inherent chemical differences between charged nucleic acids and hydrophobic drugs have hindered entrapment of both components within a single carrier. While poly(ethylene glycol)‐block‐poly(lactic‐co‐glycolic acid) (PEG–PLGA) copolymers have been used successfully for targeted delivery of chemotherapy drugs, loading of DNA or RNA has been poor. It is demonstrated that significant amounts of DNA can be encapsulated within PLGA‐containing nanoparticles through the use of a new synthetic DNA analog, click nucleic acids (CNAs). First, triblock copolymers of PEG‐CNA‐PLGA are synthesized and then formulated into polymer nanoparticles from oil‐in‐water emulsions. The CNA‐containing particles show high encapsulation of DNA complementary to the CNA sequence, whereas PEG‐PLGA alone shows minimal DNA loading, and non‐complementary DNA strands do not get encapsulated within the PEG‐CNA‐PLGA nanoparticles. Furthermore, the dye pyrene can be successfully co‐loaded with DNA and lastly, a complex, larger DNA sequence that contains an overhang complementary to the CNA can also be encapsulated, demonstrating the potential utility of the CNA‐containing particles as carriers for chemotherapy agents and gene silencers.     

Cardiovascular proteomics: translational studies to develop novel biomarkers in heart failure and left ventricular remodeling

Heart failure (HF) remains a severe disease with a poor prognosis. HF biomarkers may include demographic features, cardiac imaging, or genetic polymorphisms but this term is commonly applied to circulating serum or plasma analytes. Biomarkers may have at least three clinical uses in the context of HF: diagnosis, risk stratification, and guidance in the selection of therapy. Proteomic studies on HF biomarkers can be designed as case/control using clinical endpoints; alternatively, left ventricular remodeling can be used as a surrogate endpoint. The type of samples (tissue, cells, serum or plasma) used for proteomic analysis is a key factor in the research of biomarkers. Since the final aim is the discovery of circulating biomarkers, and since plasma and serum samples are easily accessible, proteomic analysis is frequently used for blood samples. However, standardization of sampling and access to low-abundance proteins remains problematic. Although, proteomics is playing a major role in the discovery phase of biomarkers, validation in independent populations is necessary by using more specific methods. The knowledge of new HF biomarkers may allow a more personalized medicine in the future.     

Stealth malware analysis from kernel space with Kolumbo

Most of today’s malware are able to detect traditional debuggers and change their behavior whenever somebody tries to analyze them. The analysis of such malware becomes then a much more complex task. In this paper, we present the functionalities provided by the Kolumbo kernel module that can help simplify the analysis of malware. Four functionalities are provided for the analyst: system calls monitoring, virtual memory contents dumping, pseudo-breakpoints insertion and eluding anti-debugging protections based on ptrace. The module as been designed to minimize its impact on the system and to be as undetectable as possible. However, it has not been conceived to analyze programs with kernel access.     

A spatial production analysis of Chinese regional banks: case of urban commercial banks

Urban commercial banks are regional banks which have gained tremendous importance in the last two decades in China. There is, however, a lack of research on regional banking, especially on the Chinese regional banking industry. Therefore, using an innovative spatial approach, this paper investigates the efficiency of 65 Chinese urban commercial banks across 26 regions during 2013–2017. A key finding for our sample is the significant spatial dependence of loans of Chinese urban commercial banks with their neighbouring regions’ banks. Short‐run efficiency is increasing during the research period. For regions with less than three urban commercial banks, the average efficiencies are stable and relatively high. However, regions with more banks have both the highest and lowest efficient banks at the same time. These interesting results fit with the development process of Chinese urban commercial banking, in which the market restructuring has contributed to banks’ efficiency.     

Method for estimating the future annual mass of decommissioned wind turbine blade material in Denmark

A model of the evolution of the onshore wind turbine blade mass installed in Denmark is proposed described by a Weibull distribution, and the age of the blades is estimated from decommissioning data to $$ = 29 years when half of the blade mass of an installation year has been decommissioned. This is considerably longer than the 20 year design lifetime of onshore turbines, which is often assumed to be an estimate of the End-of-Life of turbine blades. Thus, blade waste predictions using the simple assumption may predict that installed blade masses are entering recycling processes about 9 years sooner that what is observed in Denmark. The blade mass for decommissioning in Denmark is estimated to peak at 2000 and 5000 ton/year in 2028 and 2045 using the Weibull model.