bluuebunny/crossref_metadata_2025_split huggingface dataset:
Structure and properties of polypropylene/organic rectorite nanocomposites
Authors: Huang Yun , Ma Xiaoyan , Liang Guozheng , Yan Hongxia 
Published: May 2009

AbstractMelt blending using a twin-screw extruder was used to prepare composites of polypropylene (PP)/organic rectorite (PR). The organic rectorite (OREC) was modified with dodecyl benzyl dimethyl ammonium bromide (1227). Wide-angle X-ray diffraction (WAXD) and transmission electron microscopy were used to investigate the dispersion of OREC in the composites. The d spacings of OREC in PR composites was greater than in OREC itself. The dispersion of OREC particles in the PP polymer matrix was fine and uniform when the clay content was small (2 wt.%). The rheology was characterized using a capillary rheometer. The processing behaviour of the PR system improved as the amount of OREC added increased. Non-isothermal crystallization kinetics were analysed using differential scanning calorimetry. It was shown that the addition of OREC had a heterogeneous nucleation effect on PP, and can accelerate the crystallization. However, only when fine dispersion was achieved, and at lower rates of temperature decrease, was the crystallinity greater. Wide-angle X-ray diffraction and polarized light microscopy were used to observe the crystalline form and crystallite size. The PP in the PR composites exhibited an a-monoclinic crystal form, as in pure PP, and in both cases a spherulite structure was observed. However, the smaller spherulite size in the PR systems indicated that addition of OREC can reduce the crystal size significantly, which might improve the ‘toughness’ of the PP. The mechanical properties (tensile and impact strength) improved when the amount of OREC added was appropriate. Dynamic mechanical analysis showed that the storage modulus (E′) and loss modulus (E″) of the nanocomposites were somewhat greater than those of pure PP when an appropriate amount of OREC was added. Finally, thermogravimetric analysis showed that the PR systems exhibited a greater thermal stability than was seen with pure PP.
Mineralogy, geochemistry and genesis of the Taşoluk kaolinite deposits in pre-Early Cambrian metamorphites and Neogene volcanites of Afyonkarahisar, Turkey
Authors: Kadir S. , Akbulut A. 
Published: May 2009

AbstractThe Taşoluk kaolinite deposits of Afyonkarahisar (western Anatolia) are hosted by both pre-Early Cambrian sericitic mica-chlorite schists and Neogene volcanites, the latter comprising tuffs and agglomerates. These units have been affected by hydrothermal alteration controlled by faults resulting in complex, irregular, lateral mineralogical zonation. The occurrence of a siliceous cap on altered schists and in claystone, of quartz veins in schists and tuffs, and the development of explosion cones and pit fillings indicate that alteration in both the schists and the volcanites is due to hydrothermal processes. Altered schists have generally large (locally small) Fe contents, and claystones are generally silicified and have small Fe contents. Kaolinite predominates south and west of Taşoluk, whereas high (Fe+Ti)-bearing illite + kaolinite predominate in other altered sections. The kaolinite exhibits a stacked micromorphology within altered schists, and the altered volcanites recordin situprecipitation, derived from a mechanism of paired dissolution and precipitation. Illite fibres coexist with kaolinite, smectite, chlorite, mica and sericitized feldspar in markedly altered schists, revealing that the illite formed either authigenically or by conversion of smectite to illite. A relative increase in Cr+Ni and decrease in Sr+Ba in the kaolinite deposits and their schistose host rock relative to the upper level of the kaolinite deposits and their volcanic parent rocks came about by the alteration of chlorite, mica and feldspar in the sericitic mica-chlorite schists, and feldspar, glass shards and schist fragments in the volcanites as a result of extensive faulting, fracturing and hydrothermal activity during Late Miocene-Pliocene volcanism, which contributed to the development of kaolinite deposits under acidic environmental conditions. With regard to industrial applications, the low-Fe kaolinized schists are suitable for use in refractories and paper coatings, while the claystone is suitable for use in ceramics and in the white-cement industry.
Correction of murine hemophilia A following nonmyeloablative transplantation of hematopoietic stem cells engineered to encode an enhanced human factor VIII variant using a safety-augmented retroviral vector
Authors: Ramezani Ali , Hawley Robert G. 
Published: May 2009

Abstract
Insertional mutagenesis by retroviral vectors is a major impediment to the clinical application of hematopoietic stem cell gene transfer for the treatment of hematologic disorders. We recently developed an insulated self-inactivating gammaretroviral vector, RMSinOFB, which uses a novel enhancer-blocking element that significantly decreases genotoxicity of retroviral integration. In this study, we used the RMSinOFB vector to evaluate the efficacy of a newly bioengineered factor VIII (fVIII) variant (efVIII)—containing a combination of A1 domain point mutations (L303E/F309S) and an extended partial B domain for improved secretion plus A2 domain mutations (R484A/R489A/P492A) for reduced immunogenicity—toward successful treatment of murine hemophilia A. In cell lines, efVIII was secreted at up to 6-fold higher levels than an L303E/F309S A1 domain–only fVIII variant (sfVIIIΔB). Most important, when compared with a conventional gammaretroviral vector expressing sfVIIIΔB, lower doses of RMSin-efVIII-OFB–transduced hematopoietic stem cells were needed to generate comparable curative fVIII levels in hemophilia A BALB/c mice after reduced-intensity total body irradiation or nonmyeloablative chemotherapy conditioning regimens. These data suggest that the safety-augmented RMSin-efVIII-OFB platform represents an encouraging step in the development of a clinically appropriate gene addition therapy for hemophilia A.
Co-evolution of genomes and plasmids within Chlamydia trachomatis and the emergence in Sweden of a new variant strain
Authors: Seth-Smith Helena MB , Harris Simon R , Persson Kenneth , Marsh Pete , Barron Andrew , Bignell Alexandra , Bjartling Carina , Clark Louise , Cutcliffe Lesley T , Lambden Paul R , Lennard Nicola , Lockey Sarah J , Quail Michael A , Salim Omar , Skilton Rachel J , Wang Yibing , Holland Martin J , Parkhill Julian , Thomson Nicholas R , Clarke Ian N 
Published: May 2009

Abstract

Background

Chlamydia trachomatis is the most common cause of sexually transmitted infections globally and the leading cause of preventable blindness in the developing world. There are two biovariants of C. trachomatis: 'trachoma', causing ocular and genital tract infections, and the invasive 'lymphogranuloma venereum' strains. Recently, a new variant of the genital tract C. trachomatis emerged in Sweden. This variant escaped routine diagnostic tests because it carries a plasmid with a deletion. Failure to detect this strain has meant it has spread rapidly across the country provoking a worldwide alert. In addition to being a key diagnostic target, the plasmid has been linked to chlamydial virulence. Analysis of chlamydial plasmids and their cognate chromosomes was undertaken to provide insights into the evolutionary relationship between chromosome and plasmid. This is essential knowledge if the plasmid is to be continued to be relied on as a key diagnostic marker, and for an understanding of the evolution of Chlamydia trachomatis.

Results
The genomes of two new C. trachomatis strains were sequenced, together with plasmids from six C. trachomatis isolates, including the new variant strain from Sweden. The plasmid from the new Swedish variant has a 377 bp deletion in the first predicted coding sequence, abolishing the site used for PCR detection, resulting in negative diagnosis. In addition, the variant plasmid has a 44 bp duplication downstream of the deletion. The region containing the second predicted coding sequence is the most highly conserved region of the plasmids investigated. Phylogenetic analysis of the plasmids and chromosomes are fully congruent. Moreover this analysis also shows that ocular and genital strains diverged from a common C. trachomatis progenitor.

Conclusion
The evolutionary pathways of the chlamydial genome and plasmid imply that inheritance of the plasmid is tightly linked with its cognate chromosome. These data suggest that the plasmid is not a highly mobile genetic element and does not transfer readily between isolates. Comparative analysis of the plasmid sequences has revealed the most conserved regions that should be used to design future plasmid based nucleic acid amplification tests, to avoid diagnostic failures.
Key role of the 3' untranslated region in the cell cycle regulated expression of the Leishmania infantum histone H2A genes: minor synergistic effect of the 5' untranslated region
Authors: Abanades Daniel R , Ramírez Laura , Iborra Salvador , Soteriadou Ketty , González Victor M , Bonay Pedro , Alonso Carlos , Soto Manuel 
Published: May 2009

Abstract

Background
Histone synthesis in Leishmania is tightly coupled to DNA replication by a post-transcriptional mechanism operating at the level of translation.

Results
In this work we have analyzed the implication of the 5' and 3' untranslated regions (UTR) in the cell cycle regulated expression of the histone H2A in Leishmania infantum. For that purpose, L. infantum promastigotes were stably transfected with different plasmid constructs in which the CAT coding region used as a reporter was flanked by the 5' and 3' UTR regions of the different H2A genes. We report that in spite of their sequence differences, histone H2A 5' and 3' UTRs conferred a cell cycle dependent pattern of expression on the CAT reporter since de novo synthesis of CAT increased when parasites enter the S phase. Using one established L. infantum cell line we showed that CAT expression is controlled by the same regulatory events that control the endogenous histone gene expression. Thus, although we did not detect changes in the level of CAT mRNAs during cell cycle progression, a drastic change in the polysome profiles of CAT mRNAs was observed during the progression from G1 to S phase. In the S phase CAT mRNAs were on polyribosomal fractions, but in the G1 phase the association of CAT transcripts with ribosomes was impaired. Furthermore, it was determined that the addition of just the H2A 3' UTR to the CAT reporter gene is sufficient to achieve a similar pattern of post-transcriptional regulation indicating that this region contains the major regulatory sequences involved in the cell cycle dependent expression of the H2A genes. On the other hand, although CAT transcripts bearing the H2A 5' alone were translated both in the G1 and S phase, higher percentages of transcripts were detected on polyribosomes in the S phase correlating with an increase in the de novo synthesis of CAT. Thus, it can be concluded that this region also contributes, although to a minor extent than the 3' UTR, in the enhancement of translation in the S phase relative to the G1 phase.

Conclusion
Our findings indicate that both, the 5' and the 3' UTRs contain sequence elements that contribute to the cell cycle expression of L. infantum H2A. The 3' UTR region is essential for cell cycle dependent translation of the L. infantum H2A transcripts whereas the 5' UTR has a minor contribution in their S phase dependent translation.
In vitro activity of tigecycline in combination with various antimicrobials against multidrug resistant Acinetobacter baumannii
Authors: Principe Luigi , D'Arezzo Silvia , Capone Alessandro , Petrosillo Nicola , Visca Paolo 
Published: May 2009

Abstract

Background
Infections sustained by multidrug-resistant (MDR) and pan-resistant Acinetobacter baumannii have become a challenging problem in Intensive Care Units. Tigecycline provided new hope for the treatment of MDR A. baumannii infections, but isolates showing reduced susceptibility have emerged in many countries, further limiting the therapeutic options. Empirical combination therapy has become a common practice to treat patients infected with MDR A. baumannii, in spite of the limited microbiological and clinical evidence supporting its efficacy. Here, the in vitro interaction of tigecycline with seven commonly used anti-Acinetobacter drugs has been assessed.

Methods
Twenty-two MDR A. baumannii isolates from Intensive Care Unit (ICU) patients and two reference strains for the European clonal lineages I and II (including 3, 15 and 6 isolates that were resistant, intermediate and susceptible to tigecycline, respectively) were tested. Antimicrobial agents were: tigecycline, levofloxacin, piperacillin-tazobactam, amikacin, imipenem, rifampicin, ampicillin-sulbactam, and colistin. MICs were determined by the broth microdilution method. Antibiotic interactions were determined by chequerboard and time-kill assays. Only antibiotic combinations showing synergism or antagonism in both chequerboard and time-kill assays were accepted as authentic synergistic or antagonistic interactions, respectively.

Results
Considering all antimicrobials in combination with tigecycline, chequerboard analysis showed 5.9% synergy, 85.7% indifference, and 8.3% antagonism. Tigecycline showed synergism with levofloxacin (4 strains; 16.6%), amikacin (2 strains; 8.3%), imipenem (2 strains; 8.3%) and colistin (2 strains; 8.3%). Antagonism was observed for the tigecycline/piperacillin-tazobactam combination (8 strains; 33.3%). Synergism was detected only among tigecycline non-susceptible strains. Time-kill assays confirmed the synergistic interaction between tigecycline and levofloxacin, amikacin, imipenem and colistin for 5 of 7 selected isolates. No antagonism was confirmed by time-kill assays.

Conclusion
This study demonstrates the in vitro synergistic activity of tigecycline in combination with colistin, levofloxacin, amikacin and imipenem against five tigecycline non-susceptible A. baumannii strains, opening the way to a more rationale clinical assessment of novel combination therapies to combat infections caused by MDR and pan-resistant A. baumannii.
Eating late in the evening is associated with childhood obesity in some age groups but not in all children: the relationship between time of consumption and body weight status in U.S. children
Authors: Eng Stephanie , Wagstaff David A , Kranz Sibylle 
Published: May 2009

Abstract

Background
Some studies in adults indicate a positive correlation between eating later in the day and overall energy intake as well as body weight status. Thus, the time of food intake may be a risk factor in childhood obesity. This study was designed to describe the proportion of energy consumed in the time from 4 pm to midnight measured in two-hour increments and to determine a potential association between the time of proportion of energy consumed and body weight status.

Methods
Dietary, anthropometric, and socio-demographic data of 2–18 year olds (N = 11,072) of the National Health and Nutrition Examination Survey (NHANES) 1999–2004 was examined to describe the proportion of total energy consumed within two-hour time periods between 4 pm and midnight. To examine the potential association between eating later in the day and body weight status, generalized estimating equations (GEE) models were used to quantify the effect of time trends (proportion of total energy consumed in each 2-hour time period from 4 pm to 11.59 pm) on body weight status. Analysis was conducted in the total sample and in subgroups stratified by sex, ethnic group (Non-Hispanic white, Non-Hispanic black, Mexican American, Other Hispanic, and Other Race including multi-racial) and age group (2–5, 6–11, and 12–18 year olds). Complex sample survey analysis were used to assess differences at a significance level of p-value < 0.05.

Results
Proportion of energy consumed varied by sex, ethnic group, and age groups between 4 pm and 11.59 pm. Compared to healthy weight children, overweight school-age children consumed significantly higher while overweight adolescents consumed significantly lower proportions of total daily energy with each advancing two-hour time increment.

Conclusion
The association between the circadian rhythm of eating and body weight status needs to be investigated further to examine the effect of time of consumption on the risk of childhood obesity. Especially longitudinal studies in diverse child populations would help elucidate the importance of time of eating on obesity.
Clinical psychology service users' experiences of confidentiality and informed consent: A qualitative analysis
Authors: Martindale S. J. , Chambers E. , Thompson A. R. 
Published: May 2009

Objectives. To explore and describe the experience of clinical psychology service users in relation to the processes associated with confidentiality and the generation of informed consent in individual therapy.Design. A qualitative interview‐based study employing interpretative phenomenological analysis was conducted with service users. User researchers were active collaborators in the study.Methods. A focus group of four users was convened to explore issues related to confidentiality and consent, which then informed the development of the semi‐structured interview schedule. Twelve users of community mental health clinical psychology services were interviewed by user researchers. A user researcher and a clinical psychologist undertook joint analysis of the data. A second clinical psychologist facilitated reflexivity and wider consideration of validity issues.Results. Four main themes were identified from the data: being referred; the participant's feelings, mental health difficulties, and their impact; relationships with workers and carers; and autonomy.Conclusions. The meaningfulness of processes of discussing confidentiality, and generating informed consent, can be improved by psychologists placing a greater emphasis on choice, control, autonomy, individual preferences, and actively involving the user in dialogue on repeated occasions.
Perceived changes associated with autogenic training for anxiety: A grounded theory study
Authors: Yurdakul Levent , Holttum Sue , Bowden Ann 
Published: May 2009

Objectives. Autogenic training (AT) is a behaviourally orientated intervention usually taught in eight or nine sessions in the United Kingdom: clients are taught six simple mental formulae designed to induce a calm state of mind and body, five additional emotional expression exercises, and individually tailored ‘personal formulae’ for supporting positive change. In the absence of existing psychological (as opposed to neuro‐physiological) models of AT's mechanisms, this study aimed to produce the first such model, drawing on the perceptions of recent AT clients.Design. An abbreviated form of grounded theory was used to explore retrospectively and in detail the experiences of a small sample of people of the process of change.Methods. Forty people were approached and 12 women participated who had completed AT in group form after referral for anxiety. Each was interviewed individually. A preliminary model of change was produced, grounded in the interview data.Results. Factors reported to be salient were learning in a group, the core AT experience (the six standard exercises), difficulties with practice, the importance of regular practice integrated into daily life, and enhanced well‐being and coping, which incorporated reduced worrying and clearer thinking. Limitations of the study are discussed, as are areas for further research and implications for anxiety treatment.Conclusions. This was a small study with a self‐selected sample. However, theoretical generalizations can be made about the process of change. Since AT does not specifically focus on challenging negative cognitions, the cognitive changes reported have implications for anxiety treatments.
Place attachment, sense of belonging and identity in life history narratives of Iranian Baha'i refugees
Authors: Williams Ruth 
Published: May 2009

Refugees commonly experience physical and emotional displacement. Such experiences reflect Tuan's theories relating to the anxiety of separation from home and sense of estrangement or alienation in a new land. Despite this adversity, many refugees ultimately form hybrid or trans-national
identities, which allow them to operate and be accepted in two (or more) cultures. This facilitates a sense of belonging and the adaptation process to a new country and culture.
The Baha'i Faith is considered to be the second most globally widespread religion after Christianity. Thus, refugees
can potentially join a community anywhere in the world and be provided with a sense of familiarity, which the commonality of values and administrative structure provides. In addition, newcomers arriving in a new land are automatically affiliated to a collective identity to which they already
belong.
This paper draws on case study and secondary source evidence to argue that the refugee participants in this study have used the Baha'i writings, international administrative structure and global community, to construct and maintain a notion of home and sense of belonging, and thus
ultimately reflect a hybrid or trans-national identity in a new land. Preliminary findings indicate that religion plays a vital role in the lives of these refugees as the central tenets of the Baha'i Faith appear to actively inform the resettlement process in a new country. Life history narratives
were used as a tool for analysis in seven in-depth case study interviews with Iranian Baha'i refugees residing in and around the city of Melbourne, in the state of Victoria, Australia.
The participants in this study indicated that social space gave them the strongest sense of belonging,
rather than place attachment. Religious identity is explored through the affiliation to a collective membership, as it is within this context that religious identity can be strengthened via official and legitimate recognition or undermined via persecution.
Collective identity on a macro
scale can be associated with nationalism and trans-nationalism. The Baha'i attitude to nationalism is to afford a country its rightful respect, but discourage extreme nationalism as it is characteristically exclusionary by nature. However, the Iranian Baha'i refugees in this study identify
primarily as Baha'i rather than Iranian or Australian; that is, the values under-pinning their religion outweighed the importance of place or national identity. The participants in this study embraced the notion of a global home and considered themselves citizens of the world, consequently
adopting trans-national and hybrid identities. This attitude ultimately impacts on the adaptation of refugees to a new country, as they do not see themselves as moving from one home to another, but merely relocating to a different part of the one global home.