bluuebunny/crossref_metadata_2025 huggingface dataset:
Orthogonal experimental design of polydimethylsiloxane curing for the design of low-frequency vibrational energy harvester
Authors: Xie Mengying , Aw Kean , Edwards Bryn , Gao Wei , Hu Patrick
Published: June 2014

Harvesting vibrational kinetic energy from low-frequency vibrations such as human motion is a promising method to power portable electronic devices. Efficient vibrational energy harvesters can be achieved using structures with a resonant frequency matched to that of the applied vibration; however, the high stiffness of traditional materials such as silicon makes it challenging to create a compact structure with a low resonant frequency. Therefore, polydimethylsiloxane is an attractive candidate. The working frequency can be determined by the material’s Young’s modulus. The processing parameters, such as curing time, curing temperature, and mixing ratio of base and curing agent, which affect the elastic properties of polydimethylsiloxane, have previously been investigated individually but do not take into account the cross effect of these parameters. Here, for the first time using orthogonal experiment design, these parameters were considered together and two comprehensive equations have been established to model the effect of the curing parameters on the elastic properties of polydimethylsiloxane. The model was verified with additional experiments, and an energy harvester with a predicted natural frequency of ~22 Hz has been fabricated and corroborate with the experimental results.
Concept Analysis of Burden in Caregivers of Stroke Survivors During the Early Poststroke Period
Authors: Byun Eeeseung , Evans Lois K.
Published: June 2014

It is important to understand burden in caregivers of stroke survivors during the early poststroke period if we are to prevent or decrease the longer-term experience of caregiver burden and its consequences. This article reports a concept analysis of burden in caregivers of stroke survivors during the early poststroke period. A literature review using MEDLINE, PubMed, CINAHL, PsycINFO, and ISI Web of Knowledge databases (1960-2014) identified 32 relevant articles published from 1993 to 2013. Rodgers’s evolutionary method of concept analysis was used. Three attributes—objective and subjective aspects, time spent caring for the stroke survivor, and uncertainty about the future for the stroke survivor and caregiver—were identified. Multiple definitions of caregiver burden have been used. In the early poststroke period, burden appears closely interconnected with other factors, some of which may be modifiable.
Dialogic Design of Qualitative Data Collection for Researching the Mirage of Upward Mobility
Authors: Tellado Itxaso , López-Calvo Laura , Alonso-Olea María José
Published: June 2014

The mirage of upward mobility is the mistaken perception of linking the fact of having a romantic relationship with people responding to a model of dominant traditional masculinity to raising their status and attractiveness, when in fact the contrary occurs, and both status and attractiveness decrease. Investigating the phenomenon of the mirage of upward mobility as a cause of gender violence poses additional difficulty to its idiosyncrasy. To analyze this phenomenon as part of a research study, specific data collection techniques were needed and designed in dialogue with researchers and adolescents. This article involved participants from the design of the data collection techniques and the pilots carried out until the development of the research project. This dialogic design process has allowed the inclusion of true stories into the analysis of the mirage of upward mobility helping researchers and participants to advance the related knowledge.
The Ethical Tipping Points of Evaluators in Conflict Zones
Authors: Duggan Colleen , Bush Kenneth
Published: June 2014

What is different about the conduct of evaluations in conflict zones compared to nonconflict zones—and how do these differences affect (if at all) the ethical calculations and behavior of evaluators? When are ethical issues too risky, or too uncertain, for evaluators to accept—or to continue—an evaluation? These are the core questions guiding this article. The first section considers how the particularities of conflict zones affect our ability to conduct evaluations. The second section undertakes a selective review of the literature to better understand how ethical issues have been addressed both in evaluation research and in evaluation manuals. The third section draws on a series of structured conversations with evaluators to probe more deeply into the ethical challenges they face in conflict zones—with a particular interest in the “ethical tipping points” of evaluators. The fourth section considers ways evaluation actors can manage ethical challenges in conflict zones, concluding with a brief discussion of how these issues might be located more centrally in evaluation research and practice.
Rock orchestra alumni reflections on the impact of participation in The Lakewood Project
Authors: Koops Lisa Huisman , Hankins Elizabeth A. , Scalise David , Schatt Matthew D.
Published: June 2014

The purpose of this mixed-methods study was to explore the phenomenon of participation in a high school rock orchestra from the perspective of alumni. Specific research questions addressed the musicians’ reflections on experiences in the rock orchestra and the perceived possible impact on their current musical and professional lives. Survey and interview results provided a retrospective portrait of membership in the ensemble and what young adult members indicate was valuable, helpful, transformative, and transferable about participation in the rock orchestra. Textural elements of experiential learning, social-emotional processes, and skills for life were supported by structural elements of informal learning practices and a dialogue between Western classical and rock music traditions. This led to the essence of involvement identified as multi-dimensional growth through experience in a rich musical environment. We discuss whether informal learning practices may spur students to continue making music after they have left the structured environment of a school music program, the impact of student agency in their own musical space, and ways in which the rock ensemble might provide an example for integrating informal learning practices into existing school music ensemble programs.
(Re-)defining the self – Enhanced posttraumatic growth and event centrality in stroke survivors: A mixed-method approach and control comparison study
Authors: Kuenemund Anna , Zwick Sarah , Rief Winfried , Exner Cornelia
Published: June 2014

Growing evidences highlight the co-existence of negative and positive (e.g. posttraumatic growth) identity changes following stroke. Identity changes were assessed by comparing 42 survivors 21 months after stroke and healthy controls. A total of 26 stroke survivors participated in a semi-structured interview. Stroke survivors showed significantly higher posttraumatic growth ( F(1, 75) = 9.79, p = .003) and integrated the critical life event to a higher extent into their identity (event centrality) ( F(1, 74) = 37.54, p < .001). Qualitative analysis revealed increased appreciation of life and more intense/selective relationships as the most common positive changes. Considering positive changes might provide additional perspectives for rehabilitation.
Glare indicators: an analysis of ocular behaviour in an office equipped with venetian blinds
Authors: Yamín Garretón Julieta A. , Rodriguez Roberto G. , Pattini Andrea E.
Published: June 2014

This article studies the ocular behaviour of office workers in the presence of glare. Additionally, the study seeks to obtain a new indicator for glare prediction that compensates the inaccuracies of glare predicted by the existing models of glare sensation vote (GSV), daylight glare probability (DGP) and daylight glare index. A laboratory experiment was carried out (n = 18) simulating an office space. The volunteers participated in four office tasks (reading from a screen and from a paper, writing and socializing). Two scenarios were evaluated: one with sunspots on the faces of the subjects and the other with sunspots on the working area. By means of a visible spectrum eye tracker these ocular parameters were registered: direction of gaze, the degree of opening of eye and pupil size. These ocular parameters were correlated with vertical illuminance at the eye. The results show that the degree of reduction of opening of the eye was the best predictor of visual discomfort with statistically significant differences between scenarios (p = –0.728, s = 0.001). The other important predictor was the pupil size. The degree of opening of eye and pupil size was correlated with glare indices. The degree of eye opening has a good correlation with GSV and DGP and it could be a future index of visual comfort under situations of the risk of glare.
Spatial analysis of tourism income distribution in the accommodation sector in western Uganda
Authors: Adiyia Bright , Vanneste Dominique , Van Rompaey Anton , Ahebwa Wilber Manyisa
Published: June 2014

In the ongoing debate on the connection between tourism and poverty alleviation, tourism is often presented as a tool for poverty alleviation and the improvement of socio-economic conditions of rural communities in developing countries. Findings of prior research suggest that nature-based tourism has a positive impact; however, existing models tend to understate the spatial differentiation of impacts in different contexts. Little is known about the spatial range and scale of the benefits from tourism development at a certain location. Previous studies have shown that employment in accommodation facilities is responsible for the largest share of pro-poor impact in Ugandan tourism. This paper focuses on the spatial dimension of the impact of employment in the tourism accommodation sector on the local livelihoods, with nature-based tourism around Kibale National Park (KNP) in western Uganda as a case study. Semi-structured interviews with employees were undertaken to delineate the geographical sphere of influence (SoI) of tourism employment in the accommodation sector. Results show that tourism accommodations recruit from a small geographical sphere of influence (5–10 km) in rural settings, while in urbanized settings the sphere of influence is larger (30–40 km). Understanding spatial differences of the distribution of tourism benefits in developing countries can lead to better informed policies on poverty alleviation. Policies to promote tourism as a poverty alleviation strategy have shown some successes, but there is a danger that the spatial scale of the impact is smaller than anticipated. Furthermore, for more than 80% of households, tourism is the principal source of income. In addition, tourism employment can provide initial capital for supplementary activities, which gain in importance to the extent that their profits surpass the income from tourism employment. Tourism employment does not represent a final perspective but a stage for gathering resources and skills.
Proud to be Dogon: An exploration of the local perspective on cultural tourism and cultural heritage management in Dogon country, Mali
Authors: van Deursen Rosalie E , Raaphorst Wendy F
Published: June 2014

This paper explores how the local population of two Malinese villages in Dogon country, Kani Kombolé and Teli, are both managing their cultural heritage (on the United Nations Educational Scientific and Cultural Organization (UNESCO) World Heritage List since 1989) and creating a cultural tourism experience. The research is based on a project initiated by the National Ethnology Museum of the Netherlands and the Mission Culturelle in Dogon country to restore these villages. These institutes appear to be proponents of the authorised heritage discourse which perceives ‘heritage’ as aesthetic monuments which need to be ‘conserved as found’. The main question is: does the local population of Kani Kombolé and Teli comply with the authorised heritage discourse approach of these institutes or do they feel empowered to conserve, use and manage cultural heritage in their own way? It can be concluded that the local population partially manages their cultural heritage on their own terms and that this is not achieved without conflicts.
Numerical simulation of sloshing in a rectangular tank under combined horizontal, vertical and rotational oscillations
Authors: Stephen Jermie J , Sannasiraj Sannasi Annamalaisamy , Sundar Vallam
Published: June 2014

The sloshing of fluid in an enclosed tank due to regular excitation in the horizontal, vertical and rotational modes is investigated through a numerical model. Finite element method with cubic spline and finite difference approximations has been adopted to simulate the fully nonlinear sloshing wave. Herein, the external excitations, including rotational oscillation, are built-in within the kinematic and dynamic free surface boundary conditions. The predictions from the present model are compared with those of Nakayama and Wazhizu due to regular wave excitation in the roll mode, whereas the results from the combined excitations were compared with the results of Chen and Chiang. The sloshing oscillation induced by different combination of tank motions has been subjected to frequency domain analysis. The results exhibited the occurrence of dominant peak at the natural frequencies of the system, irrespective of the excitation frequency for the rotational motion. There is nearly a twofold increase in the peak amplitude if sway and roll excitations are in phase. Sloshing amplitude decreases if the vertical and rotational excitations act together.
Going large scale: The Polling Conference process for participatory constitution making in Turkey
Authors: Baburoglu Oguz N , Goker Gulru Z
Published: June 2014

This paper narrates the story of large-scale, nation-wide intervention for participatory constitution making in Turkey. The process of democratic involvement in the making of Turkey’s new Constitution has been an action research engagement since 2007 for the authors of this paper. In due process, a deliberative democracy-inspired large-scale conferencing, i.e., the Polling Conference [ Tarama Konferansı], was designed. Ordinary, unaffiliated citizens and local nongovernmental organization (NGO) members participated in the constitution-making process via attending these conferences across the nation. Reflecting upon Turkey’s first participatory constitution-making initiative and our intervention, we came to develop certain emergent themes, decisions and actions necessary for the successful realization of large-scale action research in polarized political contexts. These themes range from the establishment of a convening body and legitimate links to decision making and society, to the industrious preparation of a social-ecology on local and national levels. Our intervention is thoroughly embedded in the Turkish context; nevertheless, we came to develop a thematic approach that could set an example to nation-wide participatory initiatives in similar democratic trajectories.
The Phenomenon of Israelite Prophecy in Contemporary Scholarship
Authors: Kelle Brad E.
Published: June 2014

In the mid-twentieth century, the classic historical-critical approach to the Hebrew Bible’s prophetic books gave way to the study of Israelite prophecy as part of a social phenomenon known throughout the ancient Near East. Since the 1980s, research on the phenomenon of Israelite prophecy has been marked by two main paradigms. The first extends the basic phenomenological approach and identifies Israelite prophecy as a socio-historical phenomenon shared across various ancient cultures. Prophecy was a form of intermediation between the divine and human, and a sub-type of the larger religious practice of (non-technical) divination. The second paradigm questions the usefulness of the biblical texts for reconstructing the ancient realities of prophecy and suggests that Israelite prophecy was a literary phenomenon that emerged among scribes in postexilic Yehud. Within these paradigms, present research offers new insights on lines of inquiry, such as the relationship between prophecy and psychology, prophets in the Second Temple period, and female prophets and prophecy. Overall, scholarship reflects a sharpening distinction between ‘ancient Hebrew prophecy’ as a socio-historical phenomenon and ‘biblical prophecy’ as a literary/scribal phenomenon, and generally approaches Israelite prophecy not as a single phenomenon but as a set of related phenomena.
Steel fibre knitted fabric for automotive glass forming: Variations of the fabric thickness on the mould and glass optical quality
Authors: Barburski Marcin , Lomov Stepan , Lanckmans Filip , De Ridder Frank
Published: June 2014

Extremely fine steel fibres (12 µm diameter) are spun into yarns and then knitted into fabric, which is used, among other applications, as a mould cover in the formation of automotive glass. High requirements of the glass quality (absence of dioptric distortions) ask for a perfect evenness of the mould cover surface, which depends on the local distortions of the fabric created during tensioning of the fabric over the mould. In this paper, compression behaviour of steel knitted fabrics combined with the fabric deformation in biaxial tension and shear is studied. Interaction of the fabric with the formed glass depends on the local changes of the fabric compression behaviour due to local fabric deformations on the mould. The deformation of the fabric is further linked to quality of the glass using quantitative optical distortion system based on moiré patterns to measure glass dioptric distortions.
Zeb1 promotes androgen independence of prostate cancer via induction of stem cell-like properties
Authors: Li Ping , Wang Jia , Chu Mingliang , Zhang Kaiqing , Yang Ru , Gao Wei-Qiang
Published: June 2014

Current androgen deprivation therapy often leads to androgen independence. However, mechanism of the therapeutic failure is still not well understood. Here, we demonstrate elevated expression of Zeb1 in androgen-independent prostate cancer cells and prostate tumors of castrated PTEN conditional knockout mice. While Zeb1 shRNA resulted in a sensitization of androgen-independent prostate cancer cells, forced Zeb1 expression caused androgen-dependent prostate cancer cells to be more resistant to androgen deprivation. Moreover, such effects appeared to be mediated by induction of pluripotent genes or stem cell-like properties. Collectively, these findings suggest that inhibition of Zeb1 might be a potential therapeutic strategy for treatment of androgen-independent prostate cancer.
Modes of Cognitive Control in Official Game Handball Coaching
Authors: Debanne Thierry , Chauvin Christine
Published: June 2014

The purpose of this paper is to identify the dynamic adjustment of the cognitive control modes used by three professional head coaches during the defensive part of a handball match and, in particular, to highlight the contextual factors that have an effect on these modes. Two main aspects characterize cognitive control modes: the level of abstraction (symbolic/subsymbolic) and the origin (internal-anticipative/external-reactive) of the data used for control. Verbal communications between three coaches and their teams were recorded during 15 matches. The verbal meaningful units were encoded using a general cognitive method introduced by Amalberti and Hoc and coded using a predicate–argument format with MacSHAPA software. Analysis shows relationships between the mode of cognitive control used by coaches and the level of difficulty characterizing the situation. When the level of difficulty is low, coaches favor a reactive mode of control guided by external and subsymbolic data, whereas they favor a more abstract level of control and more internal data when facing a difficult situation. In the latter case, different coaching styles are in evidence.
Killed oral cholera vaccines: history, development and implementation challenges
Authors: Lopez Anna Lena , Gonzales Maria Liza Antoinette , Aldaba Josephine G. , Nair G. Balakrish
Published: June 2014

Cholera is still a major global health problem, affecting mainly people living in unsanitary conditions and who are at risk for outbreaks of cholera. During the past decade, outbreaks are increasingly reported from more countries. From the early killed oral cholera vaccine, rapid improvements in vaccine development occurred as a result of a better understanding of the epidemiology of the disease, pathogenesis of cholera infection and immunity. The newer-generation oral killed cholera vaccines have been shown to be safe and effective in field trials conducted in cholera endemic areas. Likewise, they have been shown to be protective when used during outbreak settings. Aside from providing direct protection to vaccinated individuals, recent studies have demonstrated that these killed oral vaccines also confer indirect protection through herd immunity. Although new-generation oral cholera vaccines should not be considered in isolation from other preventive approaches in countries where they are most needed, especially improved water quality and sanitation, these vaccines serve as immediately available public health tools for preventing further morbidity and mortality from cholera. However, despite its availability for more than two decades, use of these vaccines has not been optimized. Although there are limitations of the currently available oral cholera vaccines, recent data show that the vaccines are safe, feasible to use even in difficult circumstances and able to provide protection in various settings. Clear identification of the areas and target population groups who will benefit from the use of the cholera vaccines will be required and strategies to facilitate accessibility and usage of these vaccines in these areas and population groups will need to be developed.
Assessing Preoperative Frailty Utilizing Validated Geriatric Mortality Calculators and Their Association With Postoperative Hip Fracture Mortality Risk
Authors: Dwyer Jennifer G. , Reynoso Jason F. , Seevers Georgia A. , Schmid Kendra K. , Muralidhar Padmashri , Konigsberg Beau , Lynch Thomas G. , Johanning Jason M.
Published: June 2014

Introduction:

End-of-life surgical care is a major concern with a significant number of operations performed within the last year of life; surgery for hip fractures is a prime example. Unfortunately, no simple objective tool exists to assess life expectancy in the postoperative period. The goal of our study was to analyze 2 simple geriatric life expectancy calculators to compare with the current Veterans Affairs Surgical Quality Improvement Program (VASQIP) postoperative 30-day mortality calculator.

Methods:

This retrospective study assessed the utility of 3 validated calculators in 47 hip fracture repairs from July 2009 to May 2011. The tools included: 30-day VASQIP mortality calculator, 6-month Minimum Data Set Mortality Risk Index-Revised (MMRI-R), and Four-Year Mortality Index. The VASQIP calculator requires chart review, Current Procedural Terminology (CPT) codes, and laboratory analysis, whereas the mortality risk indices require simple patient questioning if prospective or simple chart review if retrospective. Scoring was performed and mortality risk was compared between survivors and nonsurvivors.

Results:

A total of 47 hip fractures were repaired during the study period with 37 survivors and 10 nonsurvivors. In all, 7 died within 30 days, 2 died within 6 months, and 1 died greater than 6 months after surgery. The mean age (standard deviation [SD]) of all patients undergoing hip fracture repair was 73.6 (13.3) years. The VASQIP calculator mean (SD) 30-day mortality risk was 10.4% (5.4) for nonsurvivors compared to survivors 4.3% (5.5), P < .003; the MMRI-R mean (SD) mortality risk was 35.8% (15.4) for nonsurvivors compared to survivors 14.7% (9.5), P < .001; the Four-Year Mortality Index mean (SD) mortality risk was 60.9% (16.9) for nonsurvivors compared to survivors 48.9% (24.4), P < .09.

Conclusion:

Overall, the VASQIP 30-day and MMRI-R 6-month mortality calculators showed significant differences in mortality risk between survivors versus nonsurvivors in a population with hip fracture. In contrast, the Four-Year Mortality calculator may not sufficiently discriminate operative risk. The easily obtained MMRI-R has the potential to provide information on short-term postoperative mortality risk.
“I Think I’m Reaching My Potential”
Authors: Eisenman Laura T. , Pell Megan M. , Poudel Bishwa B. , Pleet-Odle Amy M.
Published: June 2014

Through a 5-year qualitative case study of an inclusive high school, we examined students’ experiences of self-determination. We conducted analyses of multiple interviews with students, parents, teachers, guidance staff, and administrators using grounded theory methods and guided by self-determination conceptual frameworks. Explicit expectations for student agency, a network of caring autonomy-supportive adults, and integrated academic supports emerged as primary features of the students’ school experiences. We describe the participants’ perspectives about the school structures that supported those experiences and highlight three students who represented a range of responses to the school’s model of inclusive learning supports. Implications for fostering self-determination of adolescents with disabilities within general education school settings are considered.
Comparative study on laser welding characteristics of aluminium alloy under atmospheric and subatmospheric pressures
Authors: Cai C. , Peng G. C. , Li L. Q. , Chen Y. B. , Qiao L.
Published: June 2014

Laser bead on plate welding of 10 mm thick aluminium alloy under atmospheric and subatmospheric pressures were comparatively investigated. With the decrease of ambient pressure, the penetration depth increased sharply at first and then gradually levelled off. The largest penetration depth could reach 8·7 mm when welded under the pressures of 101 Pa, while only 4·9 mm under atmospheric pressure. Weld bead without any porosity was produced under ambient pressures of 10−1 Pa. The average tensile strength of joints welded under the pressure of 101 Pa was 300·2 MPa. The tensile strength remained constant as the ambient pressure decreased further. The shielding effect of plasma plume on laser beam was suppressed as the ambient pressure decreased. Therefore, the laser power deposition inside the keyhole was enhanced effectively. Under subatmospheric pressure, the porosity defects were eliminated effectively due to the keyhole stability and the change of liquid flow, i.e. moving upward along the rear wall of keyhole.
Real time monitoring of laser beam welding keyhole depth by laser interferometry
Authors: Blecher J. J. , Galbraith C. M. , Van Vlack C. , Palmer T. A. , Fraser J. M. , Webster P. J. L. , DebRoy T.
Published: June 2014

The utility of a new laser interferometric technique, inline coherent imaging, for real time keyhole depth measurement during laser welding is demonstrated on five important engineering alloys. The keyhole depth was measured at 200 kHz with a spatial resolution of 22 μm using a probe beam, which enters the keyhole coaxially with the process beam. Keyhole fluctuations limited average weld depth determination to a resolution on the order of 100 μm. Real time keyhole depth data are compared with the weld depths measured from the corresponding metallographic cross-sections. With the exception of an aluminium alloy, the technique accurately measured the average weld depth with differences of less than 5%. The keyhole depth growth rates at the start of welding are measured and compare well with order of magnitude calculations. The method described here is recommended for the real time measurement and control of keyhole depth in at least five different alloys.
Enhancement on thermal shock resistance of TBCs with EP interlayer
Authors: Lu G. X. , Hao L. J. , Cheng Z. X. , Ye F. X.
Published: June 2014

YSZ thermal barrier coatings (TBCs) were sprayed onto 2A70 aluminium by atmospheric plasma spray. To relieve the thermal stress between TBCs and aluminium substrate, Ni–P and Ni–Cu–P electroless plating (EP) were deposited onto aluminium as interlayers. The fabricated Ni–P and Ni–Cu–P EPs exhibited amorphous structure and their crystallisation temperatures were 346·4 and 356·4°C, respectively. Deposition of the interlayers did not degrade much the bonding strength of the TBCs. The thermal shock lifetimes of TBCs with Ni–P interlayer and Ni–Cu–P interlayer were approximately 600 and 200 cycles, respectively, which were enhanced compared to that of the conventional TBCs (58 cycles). The failure of the TBCs with Ni–Cu–P interlayer was mainly caused by the thermal mismatch stress induced during the thermal shock, while the TBCs with Ni–P interlayer failed due to the interdiffusion between the interlayer and the substrate and the relatively poor ductility of the Ni–P interlayer.
Influence of plasma coatings on Inconel 617 for gas turbine applications
Authors: Adam Khan M. , Sundarrajan S. , Natarajan S.
Published: June 2014

The Inconel 617 with plasma sprayed Al2O3–40%TiO2 (A40T) and NiCr–Cr2O3 coatings were investigated for the hot corrosion behaviour at 1000°C for gas turbine applications. The behaviour of the alloy under the mixed salt environment with and without V2O5 in Na2SO4 and NaCl was analysed by means of mass change per unit area, optical and SEM images along with X-ray diffraction and EDAX. Microstructural and EDAX analyses revealed presence of oxides, rich in Ni and Mo on the surface of the samples. The coated sample exhibited better corrosion resistance in A40T and NiCr – Cr2O3 coatings than bare alloy.
MicroRNA-155 influences B-cell receptor signaling and associates with aggressive disease in chronic lymphocytic leukemia
Authors: Cui Bing , Chen Liguang , Zhang Suping , Mraz Marek , Fecteau Jessie-F. , Yu Jian , Ghia Emanuela M. , Zhang Ling , Bao Lei , Rassenti Laura Z. , Messer Karen , Calin George A. , Croce Carlo M. , Kipps Thomas J.
Published: June 2014

Key Points

High-level miR-155 enhances BCR signaling, and is associated with poor prognosis in CLL. Signals within the CLL microenvironment, such as CD154 or BAFF, can induce miR-155 and enhance BCR signaling.
Optimization on condition of epigallocatechin-3-gallate (EGCG) nanoliposomes by response surface methodology and cellular uptake studies in Caco-2 cells
Authors: Luo Xiaobo , Guan Rongfa , Chen Xiaoqiang , Tao Miao , Ma Jieqing , Zhao Jin
Published: June 2014

The major component in green tea polyphenols, epigallocatechin-3-gallate (EGCG), has been demonstrated to prevent carcinogenesis. To improve the effectiveness of EGCG, liposomes were used as a carrier in this study. Reverse-phase evaporation method besides response surface methodology is a simple, rapid, and beneficial approach for liposome preparation and optimization. The optimal preparation conditions were as follows: phosphatidylcholine-to-cholesterol ratio of 4.00, EGCG concentration of 4.88 mg/mL, Tween 80 concentration of 1.08 mg/mL, and rotary evaporation temperature of 34.51°C. Under these conditions, the experimental encapsulation efficiency and size of EGCG nanoliposomes were 85.79% ± 1.65% and 180 nm ± 4 nm, which were close with the predicted value. The malondialdehyde value and the release test in vitro indicated that the prepared EGCG nanoliposomes were stable and suitable for more widespread application. Furthermore, compared with free EGCG, encapsulation of EGCG enhanced its inhibitory effect on tumor cell viability at higher concentrations.
Transcriptome and methylome profiling reveals relics of genome dominance in the mesopolyploid Brassica oleracea
Authors: Parkin Isobel AP , Koh Chushin , Tang Haibao , Robinson Stephen J , Kagale Sateesh , Clarke Wayne E , Town Chris D , Nixon John , Krishnakumar Vivek , Bidwell Shelby L , Denoeud France , Belcram Harry , Links Matthew G , Just Jérémy , Clarke Carling , Bender Tricia , Huebert Terry , Mason Annaliese S , Pires J Chris , Barker Guy , Moore Jonathan , Walley Peter G , Manoli Sahana , Batley Jacqueline , Edwards David , Nelson Matthew N , Wang Xiyin , Paterson Andrew H , King Graham , Bancroft Ian , Chalhoub Boulos , Sharpe Andrew G
Published: June 2014

Background

Brassica oleracea is a valuable vegetable species that has contributed to human health and nutrition for hundreds of years and comprises multiple distinct cultivar groups with diverse morphological and phytochemical attributes. In addition to this phenotypic wealth, B. oleracea offers unique insights into polyploid evolution, as it results from multiple ancestral polyploidy events and a final Brassiceae-specific triplication event. Further, B. oleracea represents one of the diploid genomes that formed the economically important allopolyploid oilseed, Brassica napus. A deeper understanding of B. oleracea genome architecture provides a foundation for crop improvement strategies throughout the Brassica genus.

Results

We generate an assembly representing 75% of the predicted B. oleracea genome using a hybrid Illumina/Roche 454 approach. Two dense genetic maps are generated to anchor almost 92% of the assembled scaffolds to nine pseudo-chromosomes. Over 50,000 genes are annotated and 40% of the genome predicted to be repetitive, thus contributing to the increased genome size of B. oleracea compared to its close relative B. rapa. A snapshot of both the leaf transcriptome and methylome allows comparisons to be made across the triplicated sub-genomes, which resulted from the most recent Brassiceae-specific polyploidy event.

Conclusions

Differential expression of the triplicated syntelogs and cytosine methylation levels across the sub-genomes suggest residual marks of the genome dominance that led to the current genome architecture. Although cytosine methylation does not correlate with individual gene dominance, the independent methylation patterns of triplicated copies suggest epigenetic mechanisms play a role in the functional diversification of duplicate genes.
Illumination invariant head pose estimation using random forests classifier and binary pattern run length matrix
Authors: Kim Hyunduk , Lee Sang-Heon , Sohn Myoung-Kyu , Kim Dong-Ju
Published: June 2014

In this paper, a novel approach for head pose estimation in gray-level images is presented. In the proposed algorithm, two techniques were employed. In order to deal with the large set of training data, the method of Random Forests was employed; this is a state-of-the-art classification algorithm in the field of computer vision. In order to make this system robust in terms of illumination, a Binary Pattern Run Length matrix was employed; this matrix is combination of Binary Pattern and a Run Length matrix. The binary pattern was calculated by randomly selected operator. In order to extract feature of training patch, we calculate statistical texture features from the Binary Pattern Run Length matrix. Moreover we perform some techniques to real-time operation, such as control the number of binary test. Experimental results show that our algorithm is efficient and robust against illumination change.
Mesenchymal stem cell-derived exosomes promote hepatic regeneration in drug-induced liver injury models
Authors: Tan Cheau Yih , Lai Ruenn Chai , Wong Winnie , Dan Yock Young , Lim Sai-Kiang , Ho Han Kiat
Published: June 2014

Introduction

Mesenchymal stem cell-conditioned medium (MSC-CM) has been shown to have protective effects against various cellular-injury models. This mechanism of protection, however, has yet to be elucidated. Recently, exosomes were identified as the active component in MSC-CM. The aim of this study is to investigate the effect of MSC-derived exosomes in an established carbon tetrachloride (CCl4)-induced liver injury mouse model. This potential effect is then validated by using in vitro xenobiotic-induced liver-injury assays: (1) acetaminophen (APAP)- and (2) hydrogen peroxide (H2O2)-induced liver injury.

Methods

The exosomes were introduced concurrent with CCl4 into a mouse model through different routes of administration. Biochemical analysis was performed based on the blood and liver tissues. Subsequently the exosomes were treated in APAP and H2O2-toxicants with in vitro models. Cell viability was measured, and biomarkers indicative of regenerative and oxidative biochemical responses were determined to probe the mechanism of any hepatoprotective activity observed.

Results

In contrast to mice treated with phosphate-buffered saline, CCl4 injury in mice was attenuated by concurrent-treatment exosomes, and characterized by an increase in hepatocyte proliferation, as demonstrated with proliferating cell nuclear antigen (PCNA) elevation. Significantly higher cell viability was demonstrated in the exosomes-treated group compared with the non-exosome-treated group in both injury models. The higher survival rate was associated with upregulation of the priming-phase genes during liver regeneration, which subsequently led to higher expression of proliferation proteins (PCNA and cyclin D1) in the exosomes-treated group. Exosomes also inhibited the APAP- and H2O2-induced hepatocytes apoptosis through upregulation of Bcl-xL protein expression. However, exosomes do not mitigate hepatocyte injury via modulation of oxidative stress.

Conclusions

In summary, these results suggest that MSC-derived exosomes can elicit hepatoprotective effects against toxicants-induced injury, mainly through activation of proliferative and regenerative responses.
A new fibrin sealant as a three-dimensional scaffold candidate for mesenchymal stem cells
Authors: Gasparotto Vinícius P O , Landim-Alvarenga Fernanda C , Oliveira Alexandre L R , Simões Gustavo Ferreira , Lima-Neto João F , Barraviera Benedito , Ferreira Rui S
Published: June 2014

Introduction

The optimization of an organic scaffold for specific types of applications and cells is vital to successful tissue engineering. In this study, we investigated the effects of a new fibrin sealant derived from snake venom as a scaffold for mesenchymal stem cells, to demonstrate the ability of cells to affect and detect the biological microenvironment.

Methods

The characterization of CD34, CD44 and CD90 expression on mesenchymal stem cells was performed by flow cytometry. In vitro growth and cell viability were evaluated by light and electron microscopy. Differentiation into osteogenic, adipogenic and chondrogenic lineages was induced.

Results

The fibrin sealant did not affect cell adhesion, proliferation or differentiation and allowed the adherence and growth of mesenchymal stem cells on its surface. Hoechst 33342 and propidium iodide staining demonstrated the viability of mesenchymal stem cells in contact with the fibrin sealant and the ability of the biomaterial to maintain cell survival.

Conclusions

The new fibrin sealant is a three-dimensional scaffolding candidate that is capable of maintaining cell survival without interfering with differentiation, and might also be useful in drug delivery. Fibrin sealant has a low production cost, does not transmit infectious diseases from human blood and has properties of a suitable scaffold for stem cells because it permits the preparation of differentiated scaffolds that are suitable for every need.
Surgeon Influence on Use of Needle Biopsy in Patients With Breast Cancer: A National Medicare Study
Authors: Eberth Jan M. , Xu Ying , Smith Grace L. , Shen Yu , Jiang Jing , Buchholz Thomas A. , Hunt Kelly K. , Black Dalliah M. , Giordano Sharon H. , Whitman Gary J. , Yang Wei , Shen Chan , Elting Linda , Smith Benjamin D.
Published: June 2014

Purpose

Use of needle biopsy is a proposed quality measure in the diagnosis and treatment of breast cancer, yet prior literature documents underuse. Nationally, little is known regarding the contribution of a patient's surgeon to needle biopsy use, and knowledge regarding downstream impact of needle biopsy on breast cancer care is incomplete.

Methods

Using 2003 to 2007 nationwide Medicare data from 89,712 patients with breast cancer and 12,405 surgeons, logistic regression evaluated the following three outcomes: surgeon consultation before versus after biopsy, use of needle biopsy (yes or no), and number of surgeries for cancer treatment. Multilevel analyses were adjusted for physician, patient, and structural covariates.

Results

Needle biopsy was used in 68.4% (n = 61,353) of all patients and only 53.7% of patients seen by a surgeon before biopsy (n = 32,953/61,312). Patient factors associated with surgeon consultation before biopsy included Medicaid coverage, rural residence, residence more than 8.1 miles from a radiologic facility performing needle biopsy, and no mammogram within 60 days before consultation. Among patients with surgeon consultation before biopsy, surgeon factors such as absence of board certification, training outside the United States, low case volume, earlier decade of medical school graduation, and lack of specialization in surgical oncology were negatively correlated with receipt of needle biopsy. Risk of multiple cancer surgeries was 33.7% for patients undergoing needle biopsy compared with 69.6% for those who did not (adjusted relative risk, 2.08; P < .001).

Conclusion

Needle biopsy is underused in the United States, resulting in a negative impact on breast cancer diagnosis and treatment. Surgeon-level interventions may improve needle biopsy rates and, accordingly, quality of care.
Chondrocytes Play a Major Role in the Stimulation of Bone Growth by Thyroid Hormone
Authors: Desjardin Clémence , Charles Cyril , Benoist-Lasselin Catherine , Riviere Julie , Gilles Mailys , Chassande Olivier , Morgenthaler Caroline , Laloé Denis , Lecardonnel Jérôme , Flamant Frédéric , Legeai-Mallet Laurence , Schibler Laurent
Published: June 2014

Thyroid hormone (T3) is required for postnatal skeletal growth. It exerts its effect by binding to nuclear receptors, TRs including TRα1 and TRβ1, which are present in most cell types. These cell types include chondrocytes and osteoblasts, the interactions of which are known to regulate endochondral bone formation. In order to analyze the respective functions of T3 stimulation in chondrocytes and osteoblasts during postnatal growth, we use Cre/loxP recombination to express a dominant-negative TRα1L400R mutant receptor in a cell-specific manner. Phenotype analysis revealed that inhibiting T3 response in chondrocytes is sufficient to reproduce the defects observed in hypothyroid mice, not only for cartilage maturation, but also for ossification and mineralization. TRα1L400R in chondrocytes also results in skull deformation. In the meantime, TRα1L400R expression in mature osteoblasts has no visible effect. Transcriptome analysis identifies a number of changes in gene expression induced by TRα1L400R in cartilage. These changes suggest that T3 normally cross talks with several other signaling pathways to promote chondrocytes proliferation, differentiation, and skeletal growth.
Stochastic specification of primordial germ cells from mesoderm precursors in axolotl embryos
Authors: Chatfield Jodie , O'Reilly Marie-Anne , Bachvarova Rosemary F. , Ferjentsik Zoltan , Redwood Catherine , Walmsley Maggie , Patient Roger , Loose Mathew , Johnson Andrew D.
Published: June 2014

A common feature of development in most vertebrate models is the early segregation of the germ line from the soma. For example, in Xenopus and zebrafish embryos primordial germ cells (PGCs) are specified by germ plasm that is inherited from the egg; in mice, Blimp1 expression in the epiblast mediates the commitment of cells to the germ line. How these disparate mechanisms of PGC specification evolved is unknown. Here, in order to identify the ancestral mechanism of PGC specification in vertebrates, we studied PGC specification in embryos from the axolotl (Mexican salamander), a model for the tetrapod ancestor. In the axolotl, PGCs develop within mesoderm, and classic studies have reported their induction from primitive ectoderm (animal cap). We used an axolotl animal cap system to demonstrate that signalling through FGF and BMP4 induces PGCs. The role of FGF was then confirmed in vivo. We also showed PGC induction by Brachyury, in the presence of BMP4. These conditions induced pluripotent mesodermal precursors that give rise to a variety of somatic cell types, in addition to PGCs. Irreversible restriction of the germ line did not occur until the mid-tailbud stage, days after the somatic germ layers are established. Before this, germline potential was maintained by MAP kinase signalling. We propose that this stochastic mechanism of PGC specification, from mesodermal precursors, is conserved in vertebrates.
Cadherin 6 promotes neural crest cell detachment via F-actin regulation and influences active Rho distribution during epithelial-to-mesenchymal transition
Authors: Clay Matthew R. , Halloran Mary C.
Published: June 2014

The epithelial-to-mesenchymal transition (EMT) is a complex change in cell phenotype that is important for cell migration, morphogenesis and carcinoma metastasis. Loss of epithelial cell adhesion and tight regulation of cadherin adhesion proteins are crucial for EMT. Cells undergoing EMT often display cadherin switching, where they downregulate one cadherin and induce expression of another. However, the functions of the upregulated cadherins and their effects on cell motility are poorly understood. Neural crest cells (NCCs), which undergo EMT during development, lose N-cadherin and upregulate Cadherin 6 (Cdh6) prior to EMT. Cdh6 has been suggested to suppress EMT via cell adhesion, but also to promote EMT by mediating pro-EMT signals. Here, we determine novel roles for Cdh6 in generating cell motility during EMT. We use live imaging of NCC behavior in vivo to show that Cdh6 promotes detachment of apical NCC tails, an important early step of EMT. Furthermore, we show that Cdh6 affects spatiotemporal dynamics of F-actin and active Rho GTPase, and that Cdh6 is required for accumulation of F-actin in apical NCC tails during detachment. Moreover, Cdh6 knockdown alters the subcellular distribution of active Rho, which is known to promote localized actomyosin contraction that is crucial for apical NCC detachment. Together, these data suggest that Cdh6 is an important determinant of where subcellular actomyosin forces are generated during EMT. Our results also identify mechanisms by which an upregulated cadherin can generate cell motility during EMT.
A neuron autonomous role for the familial dysautonomia geneELP1in sympathetic and sensory target tissue innervation
Authors: Jackson Marisa Z. , Gruner Katherine A. , Qin Charles , Tourtellotte Warren G.
Published: June 2014

Familial dysautonomia (FD) is characterized by severe and progressive sympathetic and sensory neuron loss caused by a highly conserved germline point mutation of the human ELP1/IKBKAP gene. Elp1 is a subunit of the hetero-hexameric transcriptional elongator complex, but how it functions in disease-vulnerable neurons is unknown. Conditional knockout mice were generated to characterize the role of Elp1 in migration, differentiation and survival of migratory neural crest (NC) progenitors that give rise to sympathetic and sensory neurons. Loss of Elp1 in NC progenitors did not impair their migration, proliferation or survival, but there was a significant impact on post-migratory sensory and sympathetic neuron survival and target tissue innervation. Ablation of Elp1 in post-migratory sympathetic neurons caused highly abnormal target tissue innervation that was correlated with abnormal neurite outgrowth/branching and abnormal cellular distribution of soluble tyrosinated α-tubulin in Elp1-deficient primary sympathetic and sensory neurons. These results indicate that neuron loss and physiologic impairment in FD is not a consequence of abnormal neuron progenitor migration, differentiation or survival. Rather, loss of Elp1 leads to neuron death as a consequence of failed target tissue innervation associated with impairments in cytoskeletal regulation.