bluuebunny/crossref_metadata_2025 huggingface dataset:
‘And the winner is …’
Authors: de Valck Marijke , Soeteman Mimi
Published: May 2010

With a commitment to artistic excellence film festivals are set apart from regular exhibition venues and commercial interests. Although one of the festivals’ key functions is to add value, few academics have carried out empirical research on festival prizes and prestige. In this article we aim to contribute to the understanding of film festivals as a network of cultural capital by reconstructing what happens behind the scenes of the Joris Ivens competition of the International Documentary Film Festival Amsterdam, analyzing, among others, jury reports and interviews with jurors. In our analysis we draw attention to the various subjective and contingent elements in the selection process as well as to the influence of the festival context in setting (expert) evaluation standards. We identify recurring elements in the jury deliberations and, following our findings, argue that festivals are not mere barometers of changing norms, but forces that drives, shape and legitimize change.
Measuring Social Capital in a Philippine Slum
Authors: Matous Petr , Ozawa Kazumasa
Published: May 2010

Social capital is crucial for slum dwellers’ survival.The central question of this article concerns how social capital can be measured. Through testing in the field, the authors optimized the position generator method for application in a Philippine slum; furthermore, they developed a special name generator to examine who gains social capital in particular community-based activities. And they were able to administer the whole measurement instrument without major difficulties to all available adults in a selected Philippine slum community. Finally, the authors inductively derived two subscales for measurement of identified domains in the social capital data and examined their relation to the respondents’ type of access to potable water.
The Teen Court Peer Influence Scale (TCPIS): Determining an Effective Way to Measure and Model Positive Peer Influence
Authors: Smith Scott , Chonody Jill M.
Published: May 2010

This article describes the development and validation of a scale designed to measure positive peer influence. Participants from six teen court sites completed an anonymous survey (N = 202), which included the newly developed Teen Court Peer Influence Scale (TCPIS). A confirmatory factor analysis (CFA) was conducted to test three measurement models to determine the best fit to the data. The final measurement model included three reciprocal factors: positive cognitions, positive identity development, and modeling positive behaviors. The model illustrated strong psychometric properties and provides a framework that may be used to augment practice.
Youth crime and justice: Key messages from the Edinburgh Study of Youth Transitions and Crime
Authors: McAra Lesley , McVie Susan
Published: May 2010

Based on findings from the Edinburgh Study of Youth Transitions and Crime, this article challenges the evidence-base which policy-makers have drawn on to justify the evolving models of youth justice across the UK (both in Scotland and England/Wales). It argues that to deliver justice, systems need to address four key facts about youth crime: serious offending is linked to a broad range of vulnerabilities and social adversity; early identification of at-risk children is not an exact science and runs the risk of labelling and stigmatizing; pathways out of offending are facilitated or impeded by critical moments in the early teenage years, in particular school exclusion; and diversionary strategies facilitate the desistance process.The article concludes that the Scottish system should be better placed than most other western systems to deliver justice for children (due to its founding commitment to decriminalization and destigmatization). However, as currently implemented, it appears to be failing many young people.
Sociological criminology and youth justice: Comparative policy analysis and academic intervention
Authors: Goldson Barry , Hughes Gordon
Published: May 2010

This article is presented in two interconnected parts. It addresses issues that have arguably received insufficient attention in most sociologically oriented criminological research and commentary on youth justice and related policy and practice developments, both within the UK jurisdictions and in wider international contexts. First, it highlights the need to recognize the complexities of comparative policy analysis at international, national, regional and local levels. Second, in the light of such complexity, the article attempts to explore the challenges confronting social science in general and sociological criminology in particular, in efforts to critically inform policymaking processes. In conclusion, it is suggested that the possibilities for vibrant, critical and publicly engaged academic intervention in the youth justice policy sphere rest upon the mobilization of theoretically and empirically based analyses, together with research-informed proposals for policy formation and practice development.
Some Plain Words on Emotion
Authors: Kagan Jerome
Published: May 2010

This article discusses several problems affecting progress in research on emotion: (1) disagreements over the appropriate referents for an emotion; (2) the modest relations between the brain states provoked by an emotional incentive and the accompanying semantic appraisals or behaviors; and (3) the abstract nature and indifference to origin of the English words used to name emotions. The final section contains some suggestions for future research.
Media Systems and the Political Information Environment: A Cross-National Comparison
Authors: Aalberg Toril , van Aelst Peter , Curran James
Published: May 2010

To express attitudes and act according to their self-interest, citizens need relevant, up-to-date information about current affairs. But has the increased commercialization in the media market increased or decreased the flow of political information? Hallin and Mancini stress that the existing empirical evidence is fragmented and that this question therefore has been difficult to answer. In this article the authors present new data that allow them to systematically examine how the flow of political information on TV occurs across six Western countries during a thirty-year period. The authors find that the flow of political information through TV varies according to the degree of commercialization. The flow of news and current affairs is lowest in the most commercially oriented television system and among the commercial TV channels. There is however important cross-national variation even within similar media systems. The authors’ data do not suggest a convergence toward the liberal system when it comes to the political information environment on TV. Rather, what strikes them is how strongly resistant some European countries have been to subordinating the needs of democracy to profit making.
Rapid semi-automated quantitative multiplex tandem PCR (MT-PCR) assays for the differential diagnosis of influenza-like illness
Authors: Szewczuk Elektra , Thapa Kiran , Anninos Terry , McPhie Kenneth , Higgins Geoff , Dwyer Dominic E , Stanley Keith K , Iredell Jonathan R
Published: May 2010

Background

Influenza A, including avian influenza, is a major public health threat in developed and developing countries. Rapid and accurate detection is a key component of strategies to contain spread of infection, and the efficient diagnosis of influenza-like-illness is essential to protect health infrastructure in the event of a major influenza outbreak.

Methods

We developed a multiplexed PCR (MT-PCR) assay for the simultaneous diagnosis of respiratory viruses causing influenza-like illness, including the specific recognition of influenza A haemagglutinin subtypes H1, H3, and H5. We tested several hundred clinical specimens in two diagnostic reference laboratories and compared the results with standard techniques.

Results

The sensitivity and specificity of these assays was higher than individual assays based on direct antigen detection and standard PCR against a range of control templates and in several hundred clinical specimens. The MT-PCR assays provided differential diagnoses as well as potentially useful quantitation of virus in clinical samples.

Conclusions

MT-PCR is a potentially powerful tool for the differential diagnosis of influenza-like illness in the clinical diagnostic laboratory.
Ovulation-inducing factor: a protein component of llama seminal plasma
Authors: Ratto Marcelo H , Huanca Wilfredo , Adams Gregg P
Published: May 2010

Background

Previously, we documented the presence of ovulation-inducing factor (OIF) in the seminal plasma of llamas and alpacas. The purpose of the study was to define the biochemical characteristics of the molecule(s) in seminal plasma responsible for inducing ovulation.

Methods

In Experiment 1, llama seminal plasma was centrifuged using filtration devices with nominal molecular mass cut-offs of 30, 10 and 5 kDa. Female llamas (n = 9 per group) were treated i.m. with whole seminal plasma (positive control), phosphate-buffered saline (negative control), or the fraction of seminal plasma equal or higher than 30 kDa, 10 to 30 kDa, 5 to 10 kDa, or < 5 kDa. In Experiment 2, female llamas (n = 7 per group) were given an i.m. dose of seminal plasma treated previously by: 1) enzymatic digestion with proteinase-K, 2) incubation with charcoal-dextran, 3) heating to 65°C, or 4) untreated (control). In Experiment 3, female llamas (n = 10 per group) were given an i.m. dose of pronase-treated or non-treated (control) seminal plasma. In all experiments, llamas were examined by transrectal ultrasonography to detect ovulation and CL formation. Ovulation rate was compared among groups by Fisher's exact test and follicle and CL diameters were compared among groups by analyses of variance or student's t-tests.

Results

In Experiment 1, all llamas in the equal or higher than 30 kDa and positive control groups ovulated (9/9 in each), but none ovulated in the other groups (P < 0.001). In Experiment 2, ovulations were detected in all llamas in each treatment group; i.e., respective treatments of seminal plasma failed to inactivate the ovulation-inducing factor. In Experiment 3, ovulations were detected in 0/10 llamas given pronase-treated seminal plasma and in 9/10 controls (P < 0.01).

Conclusions

We conclude that ovulation-inducing factor (OIF) in llama seminal plasma is a protein molecule that is resistant to heat and enzymatic digestion with proteinase K, and has a molecular mass of approximately equal or higher than 30 kDa.
Recombinant λ-phage nanobioparticles for tumor therapy in mice models
Authors: Ghaemi Amir , Soleimanjahi Hoorieh , Gill Pooria , Hassan Zuhair , Jahromi Soodeh Razeghi M , Roohvand Farzin
Published: May 2010

Lambda phages have considerable potential as gene delivery vehicles due to their genetic tractability, low cost, safety and physical characteristics in comparison to other nanocarriers and gene porters. Little is known concerning lambda phage-mediated gene transfer and expression in mammalian hosts. We therefore performed experiments to evaluate lambda-ZAP bacteriophage-mediated gene transfer and expression in vitro. For this purpose, we constructed recombinant λ-phage nanobioparticles containing a mammalian expression cassette encoding enhanced green fluorescent protein (EGFP) and E7 gene of human papillomavirus type 16 (λ-HPV-16 E7) using Lambda ZAP- CMV XR vector. Four cell lines (COS-7, CHO, TC-1 and HEK-239) were transduced with the nanobioparticles. We also characterized the therapeutic anti-tumor effects of the recombinant λ-HPV-16 E7 phage in C57BL/6 tumor mice model as a cancer vaccine. Obtained results showed that delivery and expression of these genes in fibroblastic cells (COS-7 and CHO) are more efficient than epithelial cells (TC-1 and HEK-239) using these nanobioparticles. Despite the same phage M.O.I entry, the internalizing titers of COS-7 and CHO cells were more than TC-1 and HEK-293 cells, respectively. Mice vaccinated with λ-HPV-16 E7 are able to generate potent therapeutic antitumor effects against challenge with E7- expressing tumor cell line, TC-1 compared to group treated with the wild phage. The results demonstrated that the recombinant λ-phages, due to their capabilities in transducing mammalian cells, can also be considered in design and construction of novel and safe phage-based nanomedicines.
Asthma: Eosinophil Disease, Mast Cell Disease, or Both?
Authors: Bradding Peter
Published: May 2010

Although there is much circumstantial evidence implicating eosinophils as major orchestrators in the pathophysiology of asthma, recent studies have cast doubt on their importance. Not only does anti-interleukin-5 treatment not alter the course of the disease, but some patients with asthma do not have eosinophils in their airways, whereas patients with eosinophilic bronchitis exhibit a florid tissue eosinophilia but do not have asthma. In contrast, mast cells are found in all airways and localize specifically to key tissue structures such as the submucosal glands and airway smooth muscle within asthmatic bronchi, irrespective of disease severity or phenotype. Here they are activated and interact exclusively with these structural cells via adhesive pathways and through the release of soluble mediators acting across the distance of only a few microns. The location of mast cells within the airway smooth muscle bundles seems particularly important for the development and propagation of asthma, perhaps occurring in response to, and then serving to aggravate, an underlying abnormality in asthmatic airway smooth muscle function. Targeting this mast cell-airway smooth muscle interaction in asthma offers exciting prospects for the treatment of this common disease.
VARIATION IN THE INTERPRETATION AND USE OF THE AFRICAN AMERICAN ENGLISH PREVERBALDONECONSTRUCTION
Authors: Terry J. Michael
Published: May 2010

This article examines the variable judgments that African American English speakers in Wise, North Carolina, give simple preverbal done sentences modified by definite past-time denoting adverbials, as in John done baked a cake yesterday. A single speaker might judge this sentence as perfectly grammatical one day, only to judge the same or a similar sentence as fully ungrammatical the next. The article develops a synchronic analysis of this variability based on semantic type shifting. Additionally, that account is used to reconcile other researchers' reports of different judgments coming from different regions and to help explain previously published data regarding the construction's frequency of use. Further, the article proposes that the same syntactic and semantic mechanisms be used to account for a separate, although related, case of variation within the done construction. At issue here is whether adverbially modified done constructions such as Mary done lived in Chapel Hill for three years have perfect of persistent situation readings. Different researchers have answered this question differently, with a number reporting tentative and unclear judgments similar to the Wise data.
MUMBLING IS Macho: PHONETIC DISTINCTIVENESS IN THE SPEECH OF AMERICAN RADIO Djs
Authors: Heffernan Kevin
Published: May 2010

Phonetic studies of phonological contrasts in features such as vowel height and consonant voicing have revealed a gender difference: phonetic correlates of phonological contrasts produced by women tend to be more distinct in acoustic and temporal space than those produced by men. However, these studies have been constrained by their dichotomous approach to gender. This article examines within-sex variation in phonetic correlates of phonological contrasts among eight American male radio disc jockeys. Four variables were examined: vowel space dispersion, consonant lenition, and two types of vowel length contrast. The social characteristics of the DJs were enumerated by having listeners rate each voice on 10 Likert scales. These ratings were aggregated into four components, which were interpreted as masculinity (i.e., gender), social class, regional accent, and personality. Two of these, masculinity and regional accent, showed significant correlations with the phonetic variables, demonstrating that phonetic distinctiveness correlates with speakers' social characteristics.
Pulsed-laser Irradiation of Carbonaceous Materials in AgNO3 Solution and Its Application to Preparing Silver-activated Carbon Electrodes
Authors: Koda Seiichiro , Miura Yoshiko , Endo Akira , Uchida Hiroshi , Itatani Kiyoshi
Published: May 2010

We irradiated a glassy carbon electrode in AgNO3 solution using a 532 nm pulsed laser to prepare a silver-activated electrode. The UV–visible spectrum of the solution evidenced the production of Ag particles, and transmission electron microscopic images showed the formation of carbon–silver composite on the solid carbon surface. The reduction potential of O2 measured with the prepared electrode by differential pulse voltammetry shifted positively by 0.05 V in NaClO4 solution, which indicated that the present irradiation procedure effectively activated the glassy carbon electrode.
Metallocenium Ionic Liquids
Authors: Inagaki Takashi , Mochida Tomoyuki
Published: May 2010

Ionic liquids have been prepared from simple metallocenium cations and bis(trifluoromethanesulfonyl)amide anion (TFSA). Their properties were tunable by the choice of metals and substituents; the ferrocenium salts were deep-blue paramagnetic liquids, which are readily prepared by a one-step solventless reaction, and the cobaltocenium salts were orange diamagnetic liquids.
Pure Branch Effect on the Optical Properties of Novel Conjugated Derivatives
Authors: Yang Long , Gao Fang , Liu Jian , Zhong Xiaolin , Li Hongru , Zhang Shengtao
Published: May 2010

Pure cooperative branch effects on one- and two-photon optical properties of conjugated derivatives are presented. AM1 calculations demonstrate that the electron density distribution of the frontier orbital and the dipole moment changes of the derivatives are related to the number of branches. The theoretical results show that not only the energy level of the frontier orbital could be mediated by the number of branches, but the HOMO–LUMO gap could be regulated.
Empirical Industrial Organization: A Progress Report
Authors: Einav Liran , Levin Jonathan
Published: May 2010

The field of industrial organization has made dramatic advances over the last few decades in developing empirical methods for analyzing imperfect competition and the organization of markets. These new methods have diffused widely: into merger reviews and antitrust litigation, regulatory decision making, price setting by retailers, the design of auctions and marketplaces, and into neighboring fields in economics, marketing, and engineering. Increasing access to firm-level data and in some cases the ability to cooperate with firms or governments in experimental research designs is offering new settings and opportunities to apply these ideas in empirical work. This essay begins with a sketch of how the field has evolved to its current state, in particular how the field's emphasis has shifted over time from attempts to relate aggregate measures across industries toward more focused studies of individual industries. The second and primary part of the essay describes several active areas of inquiry. We also discuss some of the impacts of this research and specify topics where research efforts have been more or less successful. The last section steps back to offer a broader perspective. We address some current debates about research emphasis in the field, and more broadly about empirical methods, and offer some thoughts on where future research might go.
Significant events in psychotherapy: An update of research findings
Authors: Timulak Ladislav
Published: May 2010

Purpose.

Significant events research represents a specific approach to studying client‐identified important moments in the therapy process. The current study provides an overview of the significant events research conducted, the methodology used together with findings and implications.

Method.

PsychInfo database was searched with keywords such as significant events, important events, significant moments, important moments, and counselling or psychotherapy. The references of the selected studies were also searched. This process led to the identification of 41 primary studies that used client‐identified significant event(s) as a main or secondary focus of the study. These were consequently reviewed with regard to their methodology and findings. The findings are presented according to type of study conducted.

Results.

The impacts of helpful events reported by clients are focused on contributions to therapeutic relationship and to in‐session outcomes. Hindering events focus on some client disappointment with the therapist or therapy. The group therapy modality highlighted additional helpful impacts (like learning from others). Perspectives on what is significant in therapy differ between clients and therapists. The intensive qualitative studies reviewed confirm that the processes involved in significant events are complex and ambiguous. Studies show that the helpful events may also contain many hindering elements and that specific events are deeply contextually embedded in the preceding events of therapy.

Conclusions.

Some studies suggest that helpful significant events are therapeutically productive although this may need to be established further. Specific intensive studies show that the clients' perceptions in therapy may differ dramatically from that of the therapist. Furthermore, the relational and emotional aspects of significant moments may be more important for the clients than the cognitive aspects of therapy which are frequently stressed by therapists.
Symphyocladia lithophila sp. nov. (Rhodomelaceae, Ceramiales), a new Korean red algal species based on morphology and rbcL sequences
Authors: Kim Myung Sook , Kim Su Yeon , Nelson Wendy
Published: May 2010

Symphyocladia lithophila sp. nov. is newly described using both morphological and molecular analyses of samples collected from the southeastern coast of Korea. The new species is characterized by small size, ecorticate thallus, with 8–10 pericentral cells, lacking trichoblasts, and having 5–7 segments of congenital fusions. S. lithophila was observed to be a winter species, producing tetrasporangia from December to February. Plastid-encoded rbcL sequences were determined in four samples of S. lithophila from different locations and 21 samples of four putative relatives, including the most related genus Pterosiphonia. All four Symphyocladia lithophila replicates from three different locations had almost identical rbcL sequences, and interspecific sequence divergences were sufficient to warrant its separation as a natural entity. The phylogeny of the rbcL sequences also indicated monophyly of the genus Symphyocladia, which is separated from the genus Pterosiphonia. The specimens of Pterosiphonia, including the type species P. cloiophylla from its type locality in South Africa, form a monophyletic group.
Evaluation of the TEST 1 erythrocyte sedimentation rate system and intra- and inter-laboratory quality control using new latex control materials
Authors: Cha Choong-Hwan , Cha Young Joo , Park Chan-Jeoung , Kim Hyun Kyung , Cha Eun-Jong , Kim Duck Hee , Honghoon  , Jung Jae-Seol , Kim Mi-Jung , Jang Seongsoo , Chi Hyun-Sook , Lee Dong Soon
Published: May 2010

Background: The erythrocyte sedimentation rate (ESR) test has been considered to be a simple procedure, not requiring quality control (QC). However, QC is essential for accuracy and precision. We evaluated the TEST 1 ESR system and performed QC procedures using newly developed latex control materials in three hospitals.

Methods: Using tripotassium ethylenediaminetetraacetic acid blood samples (n=184), we compared TEST 1 ESR values with Westergren ESR data and evaluated intra-assay precision. Three levels of latex control materials were used to assess inter-assay precision. Reference range assessment was done using samples from 220 healthy individuals. Inter-laboratory QC with latex control materials in three hospitals was performed.

Results: Correlation between TEST 1 ESR and Westergren ESR results was good (p<0.001). Intra-assay precision [coefficients of variation (CV) 6.6%–21.7%] with patient samples and inter-assay precision (CV 0.0%–6.8%) with latex control materials were satisfactory. The reference ranges of 2–10 mm/h for males and 2–19 mm/h for females were established. Inter-laboratory QC data with latex control materials in three hospitals demonstrated good accuracy and satisfactory precision (CV 0.0%–14.4%).

Conclusions: Our results demonstrate that the TEST 1 QC is reliable and the latex control materials are valuable for inter-laboratory proficiency testing.

Clin Chem Lab Med 2010;48:1043–8.
Pretreatment of Douglas Fir Wood Biomass for Improving Saccharification Efficiencies
Authors: Singhania Reeta Rani , Chiesa Simone , Sukumaran Rajeev Kumar , Villegas Juan David , Patel Anil K. , Gnansounou Edgard , Pandey Ashok
Published: May 2010

The main aim of this study was to analyze dilute acid pretreatment for the Douglas fir wood in order to improve the efficiency of hydrolysis with an ultimate aim to produce bioethanol. Compositional analysis of the untreated Douglas fir biomass revealed the presence of 63.3 % carbohydrate of which 57.2 % was C6 sugars. The total lignin content was approximately 30 %. A partial fractional factorial design was opted for performing the pretreatment experiments employing sulfuric acid (H2SO4). Acid concentration, solids loading, residence time, reaction temperature, and particle size of feedstock were evaluated simultaneously for improving the enzymatic digestibility of Douglas fir biomass. Enzymatic saccharification of the pretreated biomass was done using a commercial cellulase preparation and the total reducing sugars liberated was monitored. Saccharification efficiency was correlated with the parameters and the best combination of parameters for obtaining feedstock suited for enzymatic saccharification was determined.
Neural Correlates of Context-Dependent Perceptual Enhancement in the Inferior Colliculus
Authors: Nelson Paul C. , Young Eric D.
Published: May 2010

In certain situations, preceding auditory stimulation can actually result in heightened sensitivity to subsequent sounds. Many of these phenomena appear to be generated in the brain as reflections of central computations. One example is the robust perceptual enhancement (or “pop out”) of a probe signal within a broadband sound whose onset time is delayed relative to the remainder of a mixture of tones. Here we show that the neural representation of such stimuli undergoes a dramatic transformation as the pathway is ascended, from an implicit and distributed peripheral code to explicitly facilitated single-neuron responses at the level of the inferior colliculus (IC) of two awake and passively listening female marmoset monkeys (Callithrix jacchus). Many key features of the IC responses directly parallel psychophysical measures of enhancement, including the dependence on the width of a spectral notch surrounding the probe, the overall level of the complex, and the duration of the preceding sound (referred to as the conditioner). Neural detection thresholds for the probe with and without the conditioner were also in qualitative agreement with analogous psychoacoustic measures. Response characteristics during the conditioners were predictive of the enhancement or suppression of the ensuing probe response: buildup responses were associated with enhancement, whereas adapting conditioner responses were more likely to result in suppression. These data can be primarily explained by a phenomenological computational model using dynamic (adapting) inhibition as a necessary ingredient in the generation of neural enhancement.
Dicer in Schwann Cells Is Required for Myelination and Axonal Integrity
Authors: Pereira Jorge A. , Baumann Reto , Norrmén Camilla , Somandin Christian , Miehe Michaela , Jacob Claire , Lühmann Tessa , Hall-Bozic Heike , Mantei Ned , Meijer Dies , Suter Ueli
Published: May 2010

Dicer is responsible for the generation of mature micro-RNAs (miRNAs) and loading them into RNA-induced silencing complex (RISC). RISC functions as a probe that targets mRNAs leading to translational suppression and mRNA degradation. Schwann cells (SCs) in the peripheral nervous system undergo remarkable differentiation both in morphology and gene expression patterns throughout lineage progression to myelinating and nonmyelinating phenotypes. Gene expression in SCs is particularly tightly regulated and critical for the organism, as highlighted by the fact that a 50% decrease or an increase to 150% of normal gene expression of some myelin proteins, like PMP22, results in peripheral neuropathies. Here, we selectively deleted Dicer and consequently gene expression regulation by mature miRNAs fromMus musculusSCs. Our results show that in the absence of Dicer, most SCs arrest at the promyelinating stage and fail to start forming myelin. At the molecular level, the promyelinating transcription factor Krox20 and several myelin proteins [including myelin associated glycoprotein (MAG) and PMP22] were strongly reduced in mutant sciatic nerves. In contrast, the myelination inhibitors SOX2, Notch1, and Hes1 were increased, providing an additional potential basis for impaired myelination. A minor fraction of SCs, with some peculiar differences between sensory and motor fibers, overcame the myelination block and formed unusually thin myelin, in line with observed impaired neuregulin and AKT signaling. Surprisingly, we also found signs of axonal degeneration inDicermutant mice. Thus, our data indicate that miRNAs critically regulate Schwann cell gene expression that is required for myelination and to maintain axons via axon–glia interactions.
High Firing Rate of Neonatal Hippocampal Interneurons Is Caused by Attenuation of Afterhyperpolarizing Potassium Currents by Tonically Active Kainate Receptors
Authors: Segerstråle Mikael , Juuri Juuso , Lanore Frédéric , Piepponen Petteri , Lauri Sari E. , Mulle Christophe , Taira Tomi
Published: May 2010

In the neonatal hippocampus, the activity of interneurons shapes early network bursts that are important for the establishment of neuronal connectivity. However, mechanisms controlling the firing of immature interneurons remain elusive. We now show that the spontaneous firing rate of CA3 stratum lucidum interneurons markedly decreases during early postnatal development because of changes in the properties of GluK1 (formerly known as GluR5) subunit-containing kainate receptors (KARs). In the neonate, activation of KARs by ambient glutamate exerts a tonic inhibition of the medium-duration afterhyperpolarization (mAHP) by a G-protein-dependent mechanism, permitting a high interneuronal firing rate. During development, the amplitude of the apamine-sensitive K+currents responsible for the mAHP increases dramatically because of decoupling between KAR activation and mAHP modulation, leading to decreased interneuronal firing. The developmental shift in the KAR function and its consequences on interneuronal activity are likely to have a fundamental role in the maturation of the synchronous neuronal oscillations typical for adult hippocampal circuitry.
Evidence for the Involvement of Lfc and Tctex-1 in Axon Formation
Authors: Conde Cecilia , Arias Cristina , Robin Maria , Li Aiqun , Saito Masaki , Chuang Jen-Zen , Nairn Angus C. , Sung Ching-Hwa , Cáceres Alfredo
Published: May 2010

RhoA and Rac play key and opposite roles during neuronal polarization. We now show that Lfc, a guanosine nucleotide exchange factor (GEF), localizes to the Golgi apparatus and growth cones of developing neurons and negatively regulates neurite sprouting and axon formation through a Rho signaling pathway. Tctex-1, a dynein light chain implicated in axon outgrowth by modulating actin dynamics and Rac activity, colocalizes and physically interacts with Lfc, thus inhibiting its GEF activity, decreasing Rho-GTP levels, and functionally antagonizing Lfc during neurite formation.
Alterations of EHD1/EHD4 Protein Levels Interfere with L1/NgCAM Endocytosis in Neurons and Disrupt Axonal Targeting
Authors: Yap Chan Choo C. , Lasiecka Zofia M. , Caplan Steven , Winckler Bettina
Published: May 2010

Axon growth is regulated by many proteins, including adhesion molecules, which need to be trafficked correctly to axons. The adhesion molecule L1/neuron–glia cell adhesion molecule (NgCAM) travels to axons via an endocytosis-dependent pathway (transcytosis), traversing somatodendritic endosomes. The Eps15 homology domain (EHD) family proteins (EHD1–EHD4) play important roles in endosomal recycling and possibly in endocytosis. We investigated whether EHD1 regulates L1/NgCAM trafficking in neurons. Both short hairpin-mediated downregulation and overexpression of EHD1 led to dendritic mistargeting of NgCAM. Downregulation of EHD1 showed increased endosomal accumulation of NgCAM, whereas, surprisingly, overexpression of EHD1 led to impairment of L1/NgCAM internalization in neurons but not in fibroblasts. Transferrin internalization, however, was unaffected. At longer overexpression times of EHD1, NgCAM endocytosis returned to normal, suggesting rapid upregulation of compensatory endocytic pathways. EHD1 is capable of hetero-oligomerization, and an endogenous complex of EHD1 and EHD4 was identified previously. We therefore tested whether short-term overexpression of other EHD family members showed a similar endocytosis defect. Expression of EHD4, but not of EHD3, also caused a defect in L1/NgCAM endocytosis. Oligomerization of EHD1 was required to cause NgCAM endocytosis defects, and simultaneous expression of EHD1 and EHD4 rescued NgCAM endocytosis. Therefore, balanced levels of EHD1–EHD4 are important for NgCAM endocytosis in neurons. Our data suggest that EHD1 plays roles in both endosomal recycling and a specialized endocytosis pathway in neurons used by NgCAM. We propose that EHD1 and EHD4 act as hetero-oligomeric complexes in this pathway.
Coupling between Beta and High-Frequency Activity in the Human Subthalamic Nucleus May Be a Pathophysiological Mechanism in Parkinson's Disease
Authors: López-Azcárate Jon , Tainta Mikel , Rodríguez-Oroz María C. , Valencia Miguel , González Rafael , Guridi Jorge , Iriarte Jorge , Obeso José A. , Artieda Julio , Alegre Manuel
Published: May 2010

In Parkinson's disease (PD), the oscillatory activity recorded from the basal ganglia shows dopamine-dependent changes. In the “off” parkinsonian motor state, there is prominent activity in the beta band (12–30 Hz) that is mostly attenuated after dopaminergic therapy (“on” medication state). The on state is also characterized by activity in the gamma (60–80 Hz) and high-frequency (300 Hz) bands that is modulated by movement. We recorded local field potentials from a group of 15 PD patients (three females) treated with bilateral deep brain stimulation of the subthalamic nucleus, using a high sampling rate (2 kHz) and filters suitable to study high-frequency activity (0.3–1000 Hz). We observed high-frequency oscillations (HFOs) in both the off and on motor states. In the off state, the amplitude of the HFOs was coupled to the phase of the abnormal beta activity. The beta-coupled HFOs showed little or even negative movement-related changes in amplitude. Moreover, the degree of movement-related modulation of the HFOs correlated negatively with the rigidity/bradykinesia scores. In the on motor state, the HFOs were liberated from this beta coupling, and they displayed marked movement-related amplitude modulation. Cross-frequency interactions between the phase of slow activities and the amplitude of fast frequencies have been attributed an important role in information processing in cortical structures. Our findings suggest that nonlinear coupling between frequencies may not only be a physiological mechanism (as shown previously) but also that it may participate in the pathophysiology of parkinsonism.
Unterdrückung von Bewegungsartefakten in PPG-Signalen mittels Adaptive-Noise-Canceling
Authors: Volmer Achim , Orglmeister Reinhold , Feese Sebastian
Published: May 2010

In diesem Beitrag wird die Problematik der bewegungsbedingten Artefaktbehaftung von PPG-Siganlen im Kontext des Langzeitmonitorings untersucht. Dabei wird besonders das Potential einer Signalrekonstruktion basierend auf adaptiver Filterung mittels Beschleunigungssignalen anhand verschiedener Bewegungsmuster evaluiert und quantifiziert. Ziel ist es, die Anwendbarkeit für kontinuierliches Monitoring abzuschätzen.
Radiolytic degradation of methoxychlor in methanol and monitoring of radiolytic products by HPLC and GC-MS
Authors: Butt Shahid Bilal , Riaz Muhammad
Published: May 2010

Degradation of priority organic pollutant methoxychlor in methanol solution by gamma irradiation under varied experimental conditions has been optimized. The solution of methoxychlor was air saturated before irradiation. The extent of radiolytic degradation efficiency was monitored by reversed phase HPLC-UV; two major and two minor degradation products were detected. For 5 kGy gamma radiation dose at a rate of 200 kGy h−1≥95% methoxychlor was degraded. The degradation was also monitored by GC-ECD and the degradation products were identified using GC-MS after comparing their mass spectra with the NIST 98 m mass spectral library. It is proposed that major degradation occurs through dechlorination, dehydrochlorination, by the detachment of methoxyphenyl from methoxychlor and by interaction of other radicals generated by the methanol radiolysis. The probable reaction schemes for the formation of products have been proposed. Most of the generated products were methoxy substituted, probably due to the availability of the methoxy radical from methanol radiolysis. The identified radiolytic products of methoxychlor and the removal efficiency have been compared with those of UV photolysis. It is observed that although the source of degradation is somewhat different, the end products or radical generated species are of similar nature.
Rapid separation of lanthanides and actinides on small particle based reverse phase supports
Authors: Datta Arpita , Sivaraman N. , Srinivasan T. G. , Vasudeva Rao P. R.
Published: May 2010

This paper presents the results on the use of short columns (3−5 cm long) with small particle size (1.8 μm) for high performance liquid chromatographic separation of individual lanthanides and uranium from plutonium as well as uranium from thorium to achieve rapid separations i.e. separation time as short as 3.6 min for individual lanthanides, 1 min for thorium-uranium and 4.2 min for uranium from plutonium. These advantages can be exploited to significantly reduce analysis time, liquid waste generation as well as dose to operator when radioactive samples are analysed e.g. burn-up determination.

In the present work, a dynamic ion-exchange chromatographic separation technique was employed using camphor-10-sulfonic acid (CSA) as the ion-pairing reagent and α-hydroxy isobutyric acid (α-HIBA) as the complexing reagent for the isolation of individual lanthanides as well as the separation of uranium from thorium.

Uranium was separated from Pu(III) as well as Pu(IV) by reverse phase HPLC technique. The reverse phase HPLC was also investigated for the isolation and quantitative determination of uranium from thorium as well as lanthanide group from uranium.

The dynamic ion-exchange technique using small particle support was demonstrated for measuring the concentrations of lanthanide fission products such as La, Ce, Pr, Nd and Sm in the dissolver solution of fast reactor fuel. Similarly, the assay of uranium in the dissolver solution of fast reactor was carried out using reverse phase HPLC technique. The rapid separation technique using reverse phase HPLC was also demonstrated for separation of lanthanides as a group from uranium matrix; samples of LiCl-KCl eutectic salt containing chlorides of lanthanides in uranium matrix (typically 1:2000) were analysed.
Interactions of Sulfolobus acidocaldarius with uranium
Authors: Reitz Thomas , Merroun Mohamed , Rossberg Andre , Selenska-Pobell Sonja
Published: May 2010

Interactions of the acidothermophilic archaeon Sulfolobus acidocaldarius DSM 639 with U(VI) were studied by using a combination of batch experiments, X-ray absorption spectroscopy (XAS), and time-resolved laser-induced fluorescence spectroscopy (TRLFS). We demonstrated that at pH 2 this archaeal strain possesses a low tolerance to U(VI) and that its growth is limited to a uranium concentration below 1.1 mM. At similarly high acidic conditions (pH 1.5 and 3.0), covering the physiological pH growth optimum of S. acidocaldarius, at which U(VI) is soluble and highly toxic, rapid accumulation of the radionuclide by the cells of the strain occurred. About half of the uranium binding capacity was reached by the strain after an incubation of five minutes and nearly total saturation of the binding sites was achieved after 30 min. Both, EXAFS- and TRLF-spectroscopic analyses showed that the accumulated U(VI) was complexed mainly through organic phosphate groups. The EXAFS measurements revealed that U(VI) is coordinated to the organic phosphate ligands of the archaeal cells in a monodentate binding mode with an average U–P bond distance of 3.60±0.02 Å.
The influence of temperature on the diffusion of 125I− in Beishan Granite
Authors: Chen Tao , Sun Mao , Li Chun , Tian Wenyu , Liu Xiaoyu , Wang Luhua , Wang Xiangyun , Liu Chunli
Published: May 2010

China has planned to deal with the high-level radioactive wastes (HLW) in the middle of this century with deep geologic disposal method. The release of heat from HLW may cause the rise of temperatures in the surrounding backfilling materials or even the host rock of a repository. This brings about the concerns that the temperature elevation in the host rock may change the diffusion characteristics of key radionuclides and have some unpredictable effects in the performance assessment. In this paper, the influence of temperature on the diffusion of 125I− in Beishan Granite is studied by through diffusion method. The effective diffusion coefficients (D
e) of 125I− in the granite from 27 to 50 °C are obtained and analyzed as a function of temperature. Our result indicated that the relationship between D
e and temperature can be described by the modified Nernst equation, and the formation factors (F
f) of the granite from 27 to 50 °C is constant with an average value of 1.03×10−4.
Effect of humic acid, fulvic acid, pH, ionic strength and temperature on 63Ni(II) sorption to MnO2
Authors: Sheng Guodong , Hu Jun , Jing Han , Yang Shitong , Ren Xuemei , Li Jiaxing , Chen Yixue , Wang Xiangke
Published: May 2010

The effects of pH, ionic strength, temperature, humic acid (HA) and fulvic acid (FA) on the sorption of radionuclide 63Ni(II) to MnO2 have been investigated by using batch techniques. The results indicated that the sorption of 63Ni(II) on MnO2 is obviously dependent on pH values but independent of ionic strength. The presence of HA/FA strongly enhances the sorption of 63Ni(II) on MnO2 at low pH values, whereas reduces 63Ni(II) sorption at high pH values. The sorption of 63Ni(II) on MnO2 is attributed to inner-sphere surface complexation rather than outer-sphere surface complexation or ion exchange. The diffuse layer model (DLM) is used to simulate the experimental data well with the aid of FITEQL 3.2. The thermodynamic parameters (ΔH
0, ΔS
0, ΔG
0) are also calculated from the temperature dependent sorption isotherms, and the results suggest that the sorption of 63Ni(II) on MnO2 is a spontaneous and endothermic process.
Selective recovery of uranium from THOREX feed by hollow fibre supported liquid membrane technique containing di(2-ethylhexyl) isobutyramide (D2EHIBA) as the carrier
Authors: Pathak P. N. , Ansari S. A. , Prabhu D. R. , Kanekar A. S. , Mohapatra P. K. , Manchanda V. K.
Published: May 2010

Hollow fibre supported liquid membrane (HFSLM) studies were carried out for the selective recovery of uranium from THOREX feed solution (0.2 g/L U+200 g/L Th+0.03 M HF+0.1 M Al(NO3)3 at 4 M HNO3) using di(2-ethylhexyl) isobutyramide (D2EHIBA) as the carrier and distilled water as the strippant. About 85% of uranium was selectively transported into the receiver phase in 30 min with <1% contamination from thorium. On the other hand, under identical conditions of feed and strip solutions, about 90% of uranium was recovered in the same time when 5% TBP (tri-n-butyl phosphate) was used as the carrier, but a relatively large amount of thorium (>10%) was also co-transported to the product side. Strip phase acidity analysis revealed significant amount of acid co-transport with both the carriers. Acid transport was found to increase with the total salt content of the feed solution. The transport of metal ions was explained with the help of a theoretical model. Stability of the liquid membrane was also studied over about 5 d for long term reusability.
A Critical Evaluation of the Dynamical Thresholding Algorithm in Coupled Cluster Calculations
Authors: Auer Alexander A.
Published: May 2010

A new implementation of the Dynamical Thresholding (DT) coupled cluster doubles (CCD) approximation is presented. Using prescreening techniques for the intermediate quantities that occur in the CCD amplitude equations, a computationally efficient algorithm is obtained, in which one single threshold allows for control of accuracy. A critical evaluation of the accuracy and efficiency is carried out for two testcases. Furthermore, the issue of potential energy surface discontinuities and the usage of enveloping localized orbitals is discussed in detail.
Electron Structure Quantum Monte Carlo
Authors: Lüchow Arne , Petz Rene , Schwarz Annett
Published: May 2010

The diffusion quantum Monte Carlo method (DMC) is capable of calculating accurately the electronic energy for molecules and molecular aggregates. An overview is given on recent developments for the optimization of the guide function that determines the accuracy of the method. Furthermore, the versatility of DMC is shown with applications to Rydberg states, transition metal compounds, and weakly interacting systems.
Development of a Wavefunction-based Ab Initio Method for Metals Applying the Method of Increments
Authors: Voloshina Elena , Paulus Beate
Published: May 2010

Ab initio electron correlation calculations based on quantum-chemical methods are successfully applied to metallic systems via the method of increments, which is an expansion of the correlation energy in terms of one-body, two-body, and higher-order contributions from localized orbital groups. To deal with the two distinct problems that occur in metals, the difficulty of localization of the orbitals and the generation of clusters with neutral atoms in the center, we proposed an embedding scheme which has itself no metallic character but can mimic the metal in the internal region, where the atoms are correlated. The first application was made for solid mercury, where a very good agreement with experimental ground-state properties was achieved. Further the approach has been extended to other group 2 and 12 metals (Be, Mg, Zn, and Cd) where the metallic character is more pronounced than in mercury. Different variants of the embedding and the localized orbitals used for the incremental scheme have been developed and tested. Application of the method of increments to the investigated metallic systems allows us not only to obtain values close to experimental data but also to understand the influence of individual correlation-energy increments on cohesive properties and to clarify thereby some aspects of the structural features of the group 12 metals.