Articles de revues : « CB. User studies »

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Yaa Anima Adzobu, Nesba. « Building digital collections in a public university library in Ghana : priority-setting and user needs assessment ». Collection Building 33, n^o 2 (1 avril 2014) : 38–45. http://dx.doi.org/10.1108/cb-10-2013-0040.

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Purpose – Although user needs assessment is an intrinsic element of service quality delivery in digital libraries (DLs), not much has been written on this topic in the context of African universities. This is understandable as academic digital libraries in Africa are rather nascent. Even so, the most frequently-used needs assessment methods do not directly involve the users. This study aims to assess priority setting by academic library administrators and the needs of patrons of digital collections of a public university library in Ghana. Design/methodology/approach – Analysis of official university documents and interviews with digital library patrons at the University of Cape Coast (UCC) in Ghana were carried out between September, 2011 and January, 2012. Five research questions were asked: what are the current conditions of the UCC digital library project, the user communities and their needs, what are the priorities set by the university administrators and library leaders at the UCC and the state of technological readiness in place and what are needed by the UCCDL. Also, what is the extent of collaboration by interested parties in the UCCDL? Findings – Three general digital library user communities were identified, that is, UCCDL staff- this community was composed of experts in both digital library systems and content, characterized as heavy users of the existing systems, as knowledgeable about articulated (formalized) user needs, and able to devote short (usually less than two hours) amounts of time to individual's needs. Next, are scholars and other visitors to the UCCDL – this community was characterized as having high levels of domain expertise and knowledge of library systems. They are also able to devote large but specific amounts of time (days or weeks) to their individual information needs. Visitors/Prospective users- this community was characterized as having varied levels of domain expertise and low levels of library systems knowledge. They are able to devote only short periods of time to their information needs or explorations. These user communities are influenced by diverse preferences, experiences, and knowledge structures. Practical implications – Academic libraries are increasingly advocating local user studies as a way to provide the digital library services that are relevant to the culture and user population of the academic institution. Replicating digital library user studies at the local level can provide information for improving existing services or developing new ones. Originality/value – In African public universities, there is little earlier research on digital library user needs assessments or DL priority-setting by academic library administrators.

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Hadi Putra, Panca O., Sendhy Nugroho et Achmad Nizar Hidayanto. « Factors Affecting User Retention of Mobile Mutual Fund Investment Applications : Evidence from Indonesia ». Human Behavior and Emerging Technologies 2022 (8 octobre 2022) : 1–13. http://dx.doi.org/10.1155/2022/7521680.

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Mutual fund is one of the most popular investment programs, especially among small investors. Currently, many mobile-based applications are available, facilitating the buying and selling of mutual funds. This number of choices creates competition between application developers, pressuring them to find ways to maintain user loyalty by increasing user retention rates. However, only a few studies have currently discussed user retention in mutual fund investment applications. Furthermore, previous studies never examined the quality factor of the application but instead focused more on other factors outside the application. This study analyzed the factors influencing user retention on mutual fund investment applications in Indonesia from the application’s quality and usability aspects. This study was based on the expectation-confirmation model (ECM) as the underlying theory. Data were collected using a survey questionnaire resulting in 414 responses, which were then processed and analyzed using the covariance-based structural equation modeling (CB-SEM) technique. The results of this study indicate that three variables can directly affect user retention in mutual fund investment applications: satisfaction, perceived usefulness, and perceived enjoyment. The satisfaction variable had the most significant influence of these three variables. Several factors influenced satisfaction: perceived usefulness, enjoyment, ease of use, trust, confirmation, prompt response, and security.

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Jeon, Youngseung, Bogoan Kim, Aiping Xiong, DONGWON LEE et Kyungsik Han. « ChamberBreaker : Mitigating the Echo Chamber Effect and Supporting Information Hygiene through a Gamified Inoculation System ». Proceedings of the ACM on Human-Computer Interaction 5, CSCW2 (13 octobre 2021) : 1–26. http://dx.doi.org/10.1145/3479859.

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Because of the increasingly negative impacts of the echo chamber effect, such as the dissemination of fake news and political polarization occurring in social networking services (SNSs), considerable efforts are being made to mitigate this effect. Prior HCI studies have presented the development of user interfaces to display information that reflects various standpoints, with the aim of nudging people to consume information in a more objective fashion. However, these efforts still lack the ability to highlight the characteristics, generation processes, and negative effects of echo chambers, so they may not be effective in helping people become sufficiently aware of the echo chamber effect and those who are already in an echo chamber. In this paper, we present ChamberBreaker (CB), which has been designed to help increase a player's awareness of and preemptively respond to an echo chamber effect based on psychological concepts: inoculation, heuristics for judging, and gamification. Through a user study with 882 participants (control group: 446, experimental group: 436), we demonstrated the feasibility of our game-based methodology to support the awareness of the echo chamber effect and the importance of maintaining diverse perspectives when consuming information. Our findings highlight the externalization of psychological standpoints in mitigating an echo chamber effect and suggest design implications for system development---the consideration of demographics, playing time, and the connection to fake news recognition---for digital literacy education. You can play CB at http://tiny.cc/chamberbreaker (The game only works with Chrome.)

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Lobato-Calleros, Odette, Karla Fabila-Rodríguez et Brian Roberts. « Methodology to Improve the Acceptance and Adoption of Circular and Social Economy : A Longitudinal Case Study of a Biodiesel Cooperative ». Sustainability 14, n^o 19 (29 septembre 2022) : 12394. http://dx.doi.org/10.3390/su141912394.

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Purpose: The aim was this study was to test the effectiveness of the Mexican User Satisfaction Index of Circular and Social Economy (MUSI-CSE) methodology to improve user acceptance and the adoption of biodiesel from the Cowichan Bio-Diesel Co-op (CB-DC), a social enterprise that upcycles cooking oil waste. Approach: The external strategy is to study factors of user experience with products and/or services and internal processes. This type of economy tends to build its value chain independently to avoid barriers in the economic structure. Methodology/Techniques: MUSI-CSE presents a model of satisfaction (present acceptance) and loyalty (future acceptance) factors and a measurement system comprising the same factors. It also identifies and monitors interventions in key factors and evaluates their effectiveness. Here, MUSI-CSE has been tested through a longitudinal and prospective study. In-depth interviews, surveys, SEM, and PLS were used. Findings/originality/applicability: User acceptance and adoption are based on self-benefits and the achievement of specific sustainable local development goals. Satisfaction did not change. Loyalty did experience a statistically significant increase at a 95% confidence level, and sales increased by 26%. It can be concluded that MUSI-CSE innovation contributed to improving users’ future acceptance and adoption. In the future, MUSI-CSE will be adjusted based on other case studies and will support the co-creation of an international methodology and index of circular and social economy.

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Mason, Katherine F. « Using student activity trends to inform purchasing : a layered model for collection management ». Collection Building 35, n^o 2 (4 avril 2016) : 54–56. http://dx.doi.org/10.1108/cb-09-2015-0018.

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Purpose The purpose of this paper is to explore the development of a layered model for describing student activity that librarians can use to inform collection management decisions. It proposes using student activity in the classroom and the library, physically and virtually, to increase understanding of student curricular and research needs. The model can be used as a tool to facilitate conversations and can be adapted for use in large and small projects. Design/methodology/approach The paper used a theoretical approach using Mathematics Department as an example, with supporting evidence from existing studies and research. As a theoretical paper, data are discussed in the framework of what information you might use. Findings Experimentation suggests that the framework of student activity provides a meaningful assessment of collection contents that can be used to inform collection development activities. Implementation of the model in response to a specific research question may build evidence towards the assertion that patterns of academic activity and library use should be used to improve collection offerings. Research limitations/implications Further research is required to determine which criteria are most appropriate for inclusion in specific collection development activities and which questions are best suited for modeling. Practical implications The paper includes implications for developing student “personas” that can be used in collection building and beyond. Social implications The framework introduced can be used by libraries of any size or type to develop a layered model of student, or more generally user, activity. Originality/value This paper adds a flexible, responsive process to the body of collection assessment methods.

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Oliva, Victor T. « Deselection of print monographs in the humanities and social sciences in the digital age ». Collection Building 35, n^o 2 (4 avril 2016) : 37–47. http://dx.doi.org/10.1108/cb-02-2016-0002.

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Purpose For most college and university libraries, deselection of monographs should be an essential component of collection development. Few of these libraries have unlimited space for book stack expansion. This research study aims to cover the reasons why this should be undertaken and how it can be accomplished in the humanities and social sciences. At the main campus of Adelphi University Libraries, a conservative approach was used to identify and carefully review monograph titles that were published more than 50 years ago, and, in most cases, this resulted in their deselection without significantly affecting the collection. For some of these titles, the author determined that they might be worth replacing with available e-books and the author did so. Design/methodology/approach A brief overview is provided to delineate why deselection is important, and how it can be accomplished. A literature review was prepared. It included a review of deselection at small-, medium- and large-sized college and university libraries. The pros and cons of print versus e-books for collection development were reviewed, including four case studies. The feasibility of replacing print reference titles with e-books was also covered. A review of the monograph weeding project at the Adelphi University Library in the humanities and social sciences is provided. Conclusions and a projection of next steps are also included. Findings An overwhelming majority of the monograph titles reviewed were deselected without adversely affecting the overall quality of the collection. A small number of available e-book editions were selected to replace some of these deselected titles. Research limitations/implications All of the titles deselected were published more than 50 years ago. All of these titles were in the social sciences and humanities. The deselection review was limited to philosophy, religion, history, political science, sociology, education and psychology. There were limitations on the amount of time available to review titles in most of these fields, and as a result, only a small percentage of the titles in our collection could be reviewed. Practical implications The library has very serious space constraints, which has made it difficult to provide the needed study space for members of the Adelphi University community. Some sections of the book collection are jam packed, with no room for expansion. Deselecting older less used titles and eliminating some sections of book shelves help address both of these problems. Replacing some of these print titles with e-books contributes as well. This deselection project has reduced the holdings of monograph print titles significantly. In the future, the author hopes to rely less on print titles and more on e-books for collection development. Social implications In most fields, college and university students would be better served for their research by more recently published titles. Older, less used titles, as well as those not used at all, should be deselected to make room for more useful and up-to-date titles. As more and more titles become readily available as e-books, the collections of print titles can be reduced. Being able to use e-books even when the library is closed is a great advantage. It should also be noted that these titles can be used by more than one user simultaneously. Originality/value In conducting the literature search, the author discovered that there were a large number of titles on deselecting print titles. There was also considerable research on e-book collection development. However, there were few that linked these two important topics. In this research article and case study, the author hopes to have made a significant contribution to linking them together.

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Kato, Atsushi, Maiko Nishioka, Yoshihiro Sato, Etsuko Nagano, Riko Yamashita, Norihito Kimura et Takehiko Taguchi. « STUDIES ON BOUND RUBBER OF CB BEFORE/AFTER VULCANIZATION OF ISOPRENE RUBBER ». Rubber Chemistry and Technology 87, n^o 3 (1 septembre 2014) : 471–85. http://dx.doi.org/10.5254/rct.14.86974.

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ABSTRACT The high abrasion furnace (HAF), fast extrusion furnace (FEF), and fine thermal (FT) loadings used in this study were adjusted to keep the carbon black (CB)–specific area of cetyl trimethyl ammonium bromide adsorption to 2490 m2g−1. Their polyisoprene (IR) compounds and vulcanizates were investigated. Regarding the dependence of the CB gel fraction (FCB gel) on the IR gel/CB weight ratio (WRIR/CB), the amount of CB in the CB gel increased with a larger CB aggregate size, whereas the amount of the IR gel decreased. With regard to the dependence of the activation energy (ΔE(T2)) of the spin–spin relaxation time (T2) on the CB aggregate size, an immobilized rubber layer around CB formed more easily in the order of FT < FEF < HAF. Moreover, it became clear from the relationship between WRIR/CB and ΔE(T2) that the amount of the IR gel in the CB gel increased with decreasing ΔE(T2). The unique ratio of the surface area to the volume of CB aggregates (SCB/VCB) was obtained from results of three-dimensional transmission electron microscopy observation. The dependence of the amount of dibutyl phthalate (DBP) adsorption and compressed DBP adsorption on SCB/VCB was approximately linear, which suggested that SCB/VCB was closely related to CB aggregates and CB agglomerates. The linear relationship seen between SCB/VCB and ΔE(T2) revealed that an immobilized rubber layer was present around CB. The dependence of (qCB/qIR)(WRIR/CB) on SCB/VCB was also investigated using the densities (ρIR and ρCB) of IR and CB. The slope (tirl) of their approximately linear relationship was about 3.9 nm, which almost agreed with the bound rubber thickness reported in the literature to date. It is also inferred that because the intercept (α), which reflects the change in the IR gel weight fraction, was about 0.04 (4%), the IR gel weight fraction changed very little between before and after vulcanization.

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Miner, R. C. « What Does Obligation Add to Virtue-Descriptions ? Some Uses of Anscombe's Law/Game Analogy ». Christian Bioethics 14, n^o 2 (1 août 2008) : 165–74. http://dx.doi.org/10.1093/cb/cbn008.

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Liu, Wei, Lin Li, Bing Kai Han et Cheng Zhong Zong. « Studies on Mechanical Properties and Dynamic Performance of SSBR/CB/Silica Composites ». Key Engineering Materials 717 (novembre 2016) : 52–56. http://dx.doi.org/10.4028/www.scientific.net/kem.717.52.

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Carbon black ( CB ) and silica were used as two-component fillers to enhance the practicability of rubber. In this study, the microstructure, mechanical and dynamic properties of solution-polymerized styrene-butadiene rubber ( SSBR ) vulcanizates filled with carbon black and silica were characterized. 50 phr of total hybrid fillers was used as the base. A series of experiments with different ratios of CB/silica were carried out to determine the best contribution to the performance of SSBR vulcanizates. The studies have shown that when the vulcanizates exhibited the better overall mechanical and dynamic performance with 20 phr silica loading and 30 phr CB loading.

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Korb, Laura, Bhathika Perera et Ken Courtenay. « Challenging behaviour or untreated ADHD ? » Advances in Mental Health and Intellectual Disabilities 13, n^o 3/4 (12 juin 2019) : 152–57. http://dx.doi.org/10.1108/amhid-12-2018-0053.

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Purpose The purpose of this paper is to illustrate the possible basis of challenging behaviour (CB) can lie in a treatable neurodevelopmental disorder. Design/methodology/approach Two case studies were used to illustrate the clinical characteristics of attention deficit hyperactivity disorder (ADHD) presenting as CB in people with intellectual disability (ID). Findings The findings of this paper show that the appropriate use of drug therapy for ADHD effectively reduced the behavioural challenges. Research limitations/implications Limited by two cases. Application of the findings of this paper is limited given it is a case study. This paper highlights an important clinical implications which need to be studied in a larger scale to make clinical recommendations. Practical implications Findings from the two case studies may be used when making decisions in clinical practice. Originality/value The paper explores the possibility of ADHD presenting as CB in people with ID.

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Parvan, Marius-George, Georgeta Voicu, Alina-Ioana Badanoiu et Victor Oprisan Fruth. « Self-sensing Piezoresistive Composites Based on Cement Incorporating Low Dosage of Carbon Black Used as Multifunctional Construction Materials ». Revista de Chimie 71, n^o 5 (29 mai 2020) : 30–44. http://dx.doi.org/10.37358/rc.20.5.8110.

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HIGHLIGHTS -Carbon black (CB) particles in nanometric domain can be successfully incorporated in cement matrices in order to obtain special concretes/mortars with self-sensing properties. -Piezorezistivity monitoring of mortars is a non-destructive method used to assess the structural characteristics of composite materials. -The presence of CB in studied mortars provides a specific electrical sensitivity which may change when curing time increases. The paper presents the manufacture and characterization of special mortars based on Portland cement (PC) and a nanopowder with electrical properties (carbon black - CB). These materials were characterized from the point of view of mechanical strengths as well as properties specific for self-sensing materials i.e. variation of electrical signal when applying a mechanical strain. The electrical signal and mechanical strength values are strongly dependent on the composition and microstructure of mortars.The values of electrical resistance are strongly correlated with the composition, morphology and curing time of the mortars. In this study significant changes of the electrical behaviour (piezoresistivity) of the mortars vs. curing time (90 or 180 days) were noticed, so this must be considered in practical applications. The best results were obtained for the mortars with 0.5-3 wt.% CB cured for 180 days.

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Hou, Xiaoxiao, Jun Liu, Zhiren Zhang, Yanhui Zhai, Yutian Wang, Zhengzhu Wang, Bo Tang, Xueming Zhang, Liguang Sun et Ziyi Li. « Effects of cytochalasin B on DNA methylation and histone modification in parthenogenetically activated porcine embryos ». Reproduction 152, n^o 5 (novembre 2016) : 519–27. http://dx.doi.org/10.1530/rep-16-0280.

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DNA methylation and histone modification play important roles in the development of mammalian embryos. Cytochalasin B (CB) is an actin polymerization inhibitor that can significantly affect cell activity and is often used in studies concerning cytology. In recent years, CB is also commonly being used inin vitroexperiments on mammalian embryos, but few studies have addressed the effect of CB on the epigenetic modification of embryonic development, and the mechanism underlying this process is also unknown. This study was conducted to investigate the effects of CB on DNA methylation and histone modification in the development of parthenogenetically activated porcine embryos. Treatment with 5 μg/mL CB for 4 h significantly increased the cleavage rate, blastocyst rate and total cell number of blastocysts. However, the percentage of apoptotic cells and the expression levels of the apoptosis-related genesBCL-XL,BAXandCASP3were significantly decreased. Treatment with CB significantly decreased the expression levels ofDNMT1,DNMT3a,DNMT3b,HAT1andHDAC1at the pronuclear stage and promoted the conversion of 5-methylcytosine (5mC) into 5-hydroxymethylcytosine (5hmC). After CB treatment, the level of AcH3K9 was upregulated and the level of H3K9me3 was downregulated. When combined with Scriptaid and 5-Aza-Cdr, CB further improved the embryonic development competence and decreased the expression ofBCL-XL,BAXandCASP3. In conclusion, these results suggest that CB could improve embryonic development and the quality of the blastocyst by improving the epigenetic modification during the development of parthenogenetically activated embryos.

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Lee, Young Hoon, Yongdai Kim et Sara Kim. « Competitive balance with unbalanced schedules ». Journal of Quantitative Analysis in Sports 15, n^o 3 (27 août 2019) : 239–60. http://dx.doi.org/10.1515/jqas-2017-0100.

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Abstract Many empirical studies on competitive balance (CB) use the ratio of the actual standard deviation to the idealized standard deviation of win percentages (RSD). This paper suggests that empirical studies that use RSD to compare CB among different leagues are invalid, but that RSD may be used for time-series analysis on CB in a league if there are no changes in season length. When schedules are unbalanced and/or include interleague games, the final winning percentage is a biased estimator of the true win probability. This paper takes a mathematical statistical approach to derive an unbiased estimator of within-season CB that can be applied to not only balanced but also unbalanced schedules. Simulations and empirical applications are also presented, which confirm that the debiasing strategy to obtain the unbiased estimator of within-season CB is still effective for unbalanced schedules.

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Oran, Betul, et Elizabeth Shpall. « Umbilical cord blood transplantation : a maturing technology ». Hematology 2012, n^o 1 (8 décembre 2012) : 215–22. http://dx.doi.org/10.1182/asheducation.v2012.1.215.3798291.

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Abstract The use of umbilical cord blood (CB) as a source of hematopoietic progenitor cells for patients with high-risk hematologic disorders receiving allogeneic hematopoietic cell transplantations (HCTs) has increased significantly. Single-institution and registry studies have shown a decreased relapse rate and an increased transplantation-related mortality rate with similar overall survival rates after allogeneic HCT with CB compared with other donor sources. The transplantation of double CB units has overcome the dose limitation inherent in a single CB unit and thus has markedly extended the use of CB to larger children and adults. Similarly, the use of reduced intensity conditioning in the CB transplantation setting has allowed the treatment of older patients who would be unable to tolerate the myeloablative regimens used in the original CB transplantation protocols.

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Shivashankar, Hiremath, et S. M. Kulkarni. « Modelling and Analysis of Thermomechanical Behaviour in Composite Bimorph Actuator ». Materials Science Forum 928 (août 2018) : 209–14. http://dx.doi.org/10.4028/www.scientific.net/msf.928.209.

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This paper presents study of a thermomechanical bimorph actuator, constituted by layers of polymer composite material. The proposed bimorph consists of polydimethylsiloxane (PDMS) and carbon black-polydimethylsiloxane (CB-PDMS) polymer composite layered structure. The thermomechanical response of the PDMS and CB-PDMS material is studied. Deflection of bimorph for change in temperature is studied for different thickness and volume percentage of CB bimorph. Three different thicknesses and three volume fractions of CB are used for analysis of bimorph. Deflections of the bimorph are obtained from two different approaches analytical and FE. The modelling of bimorph carried out using multi-physics (FE) software. Results obtained from above approaches are agreeing well with different volume fractions of CB and thickness. It is observed that the bimorph with higher amount of CB has larger deflection. An optimum deflection achieved in an equal layer of bimorph actuators. In this study, the largest displacement noticed at 6 mm thick CB-PDMS layer with 5 Vol% of carbon black filler.

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Deng, Hua, Ya Fen Li, Shu Qi Tao, An Yu Li, Qiu Yan Li et Le Ning Hu. « Efficient adsorption capability of banana and cassava biochar for malachite green : Removal process and mechanism exploration ». Environmental Engineering Research 27, n^o 3 (1 mai 2021) : 200575–0. http://dx.doi.org/10.4491/eer.2020.575.

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In this study, banana biochar (BB) and cassava biochar (CB) were roasted in a tube furnace at 400℃ for 2 h, and their adsorption effects on malachite green (MG) were studied. The removal of MG with respect to the solution concentration and reaction time was also investigated. The results show that the optimal amount of biochar is 2 g/L. Studies of the adsorption kinetics and adsorption isotherms show that the pseudo-second-order kinetics can most accurately reflect the adsorption process. Freundlich model fits the experimental data well. The theoretical saturated adsorption capacities of BB and CB are 1,092.80 mg/g and 261.42 mg/g, respectively. SEM-EDS, TGA, BET, FTIR, XRD, element analysis and other characterization techniques were used to explore the adsorption mechanism. Based on the characterization results, it is speculated that the adsorption of BB and CB for MG mainly includes chemical adsorption and physical adsorption.

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Hadri, Mustapha El, Serge Bresson, Albane Lecuelle, Fatiha Bougrioua, Vincent Baeten, Van Hung Nguyen, Vincent Faivre et Matthieu Courty. « Structural and Vibrational Investigations of Mixtures of Cocoa Butter (CB), Cocoa Butter Equivalent (CBE) and Anhydrous Milk Fat (AMF) to Understand Fat Bloom Process ». Applied Sciences 12, n^o 13 (29 juin 2022) : 6594. http://dx.doi.org/10.3390/app12136594.

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Some studies found that the proportions of cocoa butter (CB), cocoa butter equivalent (CBE) and milk fatty acid (AMF) tend to influence the blooming delay when mixing them. The goal of our research is to determine the effects of the proportion of CB, CBE and AMF on the structural organization of the final mixtures. X-ray, DSC, MIR and Raman spectroscopy were used to analyze the structural features and the vibrational modes of four mixtures: CB + 0.5AMF, CB + AMF, CB + 0.5AMF + CBE and CB + AMF + CBE. At room temperature, the triglycerides are ingredients of CB, and CBE and AMF do not fully exhibit the known crystalline forms V or VI, unlike a recent CB sample. Part of these triglycerides is in the form IV instead. The presence of the latter seems to be a key parameter that favors the deceleration of the transformation to the form VI, which is responsible for the development of fat bloom.

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Silva, Tiago Almeida, Fernando Cruz Moraes, Bruno Campos Janegitz et Orlando Fatibello-Filho. « Electrochemical Biosensors Based on Nanostructured Carbon Black : A Review ». Journal of Nanomaterials 2017 (2017) : 1–14. http://dx.doi.org/10.1155/2017/4571614.

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Carbon black (CB) is a nanostructured material widely used in several industrial processes. This nanomaterial features a set of remarkable properties including high surface area, high thermal and electrical conductivity, and very low cost. Several studies have explored the applicability of CB in electrochemical fields. Recent data showed that modified electrodes based on CB present fast charge transfer and high electroactive surface area, comparable to carbon nanotubes and graphene. These characteristics make CB a promising candidate for the design of electrochemical sensors and biosensors. In this review, we highlight recent advances in the use of CB as a template for biosensing. As will be seen, we discuss the main biosensing strategies adopted for enzymatic catalysis for several target analytes, such as glucose, hydrogen peroxide, and environmental contaminants. Recent applications of CB on DNA-based biosensors are also described. Finally, future challenges and trends of CB use in bioanalytical chemistry are discussed.

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Singer, J. W., F. B. Oldham, B. Bandstra, L. Sandalic, J. Bianco, P. Bonomi et H. Ross. « Serum cathepsin B (CB) levels are prognostic in chemotherapy-naive patients (pts) with advanced non-small cell lung cancer (NSCLC) and performance status (PS) of 2 ». Journal of Clinical Oncology 25, n^o 18_suppl (20 juin 2007) : 18036. http://dx.doi.org/10.1200/jco.2007.25.18_suppl.18036.

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18036 Background: CB is an estrogen-influenced lysosomal cysteine protease produced by tumor cells and tumor-associated macrophages; tumor tissue CB protein levels and proteolytic activity are prognostic in NSCLC (Anticancer Res. 2004; 24:4147–61). The prognostic value of serum CB has not previously been evaluated in NSCLC. Here we evaluate the impact of pretreatment CB levels on survival in pts from 2 phase III trials in advanced NSCLC, STELLAR 3 and 4. These trials compared paclitaxel poliglumex (PPX) against commonly used regimens. As the intratumoral metabolic pathway of PPX is characterized by the CB-mediated release of paclitaxel (P) from a polymeric backbone (Ca Chemother Pharm. 2006. Epub ahead of print), correlation of CB levels with PPX efficacy was assessed as well. Methods: Pretreatment serum samples from 450 chemo-naive pts with advanced NSCLC and PS 2 enrolled in STELLAR 3 (P + carboplatin (C) v. PPX + C) (N=315) and STELLAR 4 (vinorelbine or gemcitabine v. PPX) (N=135) were assayed for CB by ELISA (ICON Labs). Values were assessed by quartiles and there was a clear breakpoint at the median. Pts were categorized as high or low CB based on values above or below the median (64 ng/ml). The effect of CB levels on survival was evaluated by log rank for pooled pts from the studies. Results: As detailed in the table , median survival for non-PPX-treated pts was worse if CB was high; in contrast, median survival for PPX-treated pts did not differ by CB level. Pts with high CB receiving PPX showed a trend towards better survival compared to those receiving control regimens. Conclusions: The data suggest that serum CB may be prognostic biomarker for NSCLC. Retrospective analysis suggests a trend towards improved survival in patients with high CB receiving PPX; prospective studies are required to confirm this observation. [Table: see text] No significant financial relationships to disclose.

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Wang, Xuefei, Lingling Wu, Tongliang Xiao, Haiwen Yu, Huaming Li et Jun Yang. « Preparation and application of carbon black-filled rubber composite modified with a multi-functional silane coupling agent ». International Polymer Processing 37, n^o 1 (25 février 2022) : 15–24. http://dx.doi.org/10.1515/ipp-2021-4124.

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Abstract Carbon black (CB)-filled rubber composites are widely used for tire tread and other rubber products due to their good abrasion resistance and reinforcement. Numerous studies have been focused on the filler-rubber interaction with the aim of obtaining optimum performances. In order to investigate the effect of modification on properties of diene rubber composites, a modified CB-filled isoprene rubber (IR) composite was prepared with a multi-functional silane coupling agent, 2-aminoethyl-2-(3-triethoxysilylpropyl)aminoethyl disulfide (ATD). This modification significantly enhanced the CB-IR interaction and improved CB dispersion. For the modified CB/IR vulcanizates, the tensile strength, stress at 300% elongation, temperature rise, and dynamic loss coefficient were significantly improved at low ATD dosage (1.5 phr). Such modification provides an effective route to prepare CB-reinforced diene rubber composites with low hysteresis and improved mechanical properties.

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Sarvaria, Anushruti, Robert David Danby, J. Alejandro Madrigal et Aurore Saudemont. « Cord Blood IL-15 Activated NK Cells Increase Cord Blood CD34+CD133+CD45lo Cell Function through IFN-y Production and Direct Cell Contact ». Blood 132, Supplement 1 (29 novembre 2018) : 2032. http://dx.doi.org/10.1182/blood-2018-99-111820.

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Abstract Delayed engraftment following cord blood (CB) transplantation remains a significant challenge. While cell dose is clearly limiting, CB derived hematopoietic stem cells (HSCs) also exhibit a deficit in homing and engraftment. IL-15 activated natural killer (NK) cells have been shown as potential promoters of homing and engraftment of CB HSCs. However, the role of NK cells and their underlying mechanisms in promoting CB HSCs requires further study. Here, we explore the effect of IL-15 activated CB NK cells on the functional properties of CB CD34+CD133+CD45lo HSCs. In addition, we define the mechanistic interaction between NK cells and HSCs that may increase CB-HSC engraftment and improve patient outcome post-HSC transplantation. We first determined whether IL-15 activated NK cells could improve HSC function in vitro. Purified CD56+CD3- NK cells from CB were stimulated overnight with IL-15 and cultured at a 1:5 cell ratio with autologous purified CD34+CD133+CD45lo cells (CB HSCs). IL-15 activated NK cells increased CXCR4 expression on CB HSCs when compared to cultures with resting NK cells or CB HSCS alone. As HSCs must migrate to the bone marrow in order to engraft and facilitate long-term immune reconstitution, we next assessed whether NK cells also impact on HSC migration, clonogenicity and proliferation. We found that elevated levels of CXCR4 on CB HSCs cultured with activated NK cells also translated into enhanced chemotaxis towards SDF-1α in vitro. IL-15 activated CB NK cells also increased CB HSC clonogenicity as evaluated by short-term in vitro cultures. The effect of activated NK cells on the clonogenic capacity of CB HSCs was cell dose dependent with the highest effect observed at a ratio of 1:10. To study CB HSC proliferation, CFSE stained CD34+CD133+CD45lo cells were cultured either alone, with resting NK cells or IL-15 activated NK cells. Cultures with IL-15 activated NK cells significantly increased CB HSC proliferation when compared to cultures with resting NK cells or CB HSCs alone [median percentage of proliferating CB-HSCs; 38.4% (34%-44.6%) vs. 46.7% (36%-53.4%) vs. 69% (59.6%-78.5%)]. Moreover, following the ability of IL-15 activated NK cells to upregulate CB HSC proliferation, we investigated whether CB HSCs still retained their long-term engraftment potential. We found that proliferating CB HSCs still recalled both their short-term and long term clonogenic capacity as evaluated by CFU assays and cobblestone cultures followed by long-term culture (LTC-IC) respectively. Finally, we demonstrated that IL-15 activated NK cells also possessed the ability to activate pAkt/pErk and pStat3. As pAkt/pErk and pStat3 are key mediators of cell survival proliferation, our findings identify that NK cells may promote the survival and proliferation of CB HSCs through activating pAkt/pErk and pStat3. These data suggest that IL-15 activated NK cells from CB are endowed with properties to promote the functional profile of CB HSCs that contribute to improved engraftment. To further understand the underlying mechanisms through which IL-15 activated NK cells exert their ability to upregulate the functional profile of CB HSCs, we used antibody blockade experiments. We showed that the ability of NK cells to increase CXCR4 expression on CB HSCs was mediated via the provision of IFN-γ, but not TNF-α or TNF-β. Whereas, the effect of NK cells on CB HSC function studied through clonogenicity, proliferation and signalling studies was only partially dependent on IFN-γ production by IL-15 activated NK cells. Using transwell experiments, we further determined that the ability of activated NK cells to upregulate CB HSC function is also partly dependent on direct NK cell/HSC cell contact. Subsequently, we found that the addition of blocking antibody against 2B4 in cultures containing IL-15 activated NK cells and CB HSC partially reversed the ability of NK cells to increase the clonogenic capacity, proliferation and Akt/Erk and Stat3 signalling of CB HSCs. Thus, the ability of IL-15 activated NK cells to increase the functional profile of CB HSCs depends on IFN-γ production and cell-cell contact involving 2B4. Our combined studies demonstrate a novel effect of IL-15 activated CB NK cells and their key factors as potential mediators of stem cell homing and engraftment, which could be utilized to develop strategies that will benefit all patients with haematological malignancies and improve CB transplantation. Disclosures No relevant conflicts of interest to declare.

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Castro-Alayo, Efraín M., Llisela Torrejón-Valqui, Marleni Medina-Mendoza, Ilse S. Cayo-Colca et Fiorella P. Cárdenas-Toro. « Kinetics Crystallization and Polymorphism of Cocoa Butter throughout the Spontaneous Fermentation Process ». Foods 11, n^o 12 (15 juin 2022) : 1769. http://dx.doi.org/10.3390/foods11121769.

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The spontaneous fermentation process of Criollo cocoa is studied for its importance in the development of chocolate aroma precursors. This research supports the importance of spontaneous fermentation, which was studied through the crystallization behavior and polymorphisms of cocoa butter (CB), the most abundant component of chocolate that is responsible for its quality physical properties. The k-means technique was used with the CB crystallization kinetics parameters to observe the division of the process during the first stage (day 0–3). The experimental crystallization time was 15.78 min and the second stage (day 4–7) was 17.88 min. The Avrami index (1.2–2.94) showed that the CB crystallizes in the form of a rod/needle/fiber or plate throughout the process. CB produced metastable crystals of polyforms β1′ and β2′. Three days of fermentation are proposed to generate Criollo cocoa beans with acceptable CB crystallization times.

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Zhong, Kunzhi, Zhi Li, Jianwei Fan, Guangji Xu et Xiaoming Huang. « Effect of Carbon Black on Rutting and Fatigue Performance of Asphalt ». Materials 14, n^o 9 (3 mai 2021) : 2383. http://dx.doi.org/10.3390/ma14092383.

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As an additive to improve the performance of asphalt binder, tire pyrolysis carbon black is gradually being used in road engineering, but the effect of carbon black (CB) with different particle sizes on asphalt modification remains to be further studied. In this study, three kinds of particle sizes and three kinds of contents of CB were used to modify asphalt, and different tests were conducted to research the high temperature performance and fatigue resistance of carbon black modified asphalt binder. It is found that the addition of CB can enhance the rutting resistance and medium temperature fatigue performance of virgin asphalt binder in general. However, for CB of 270 μm and 2.6 μm, its addition under certain contents lead to the decrease of high temperature performance and fatigue performance of the asphalt binder. For aged asphalt, the addition of CB decreases the rutting resistance and improves the fatigue resistance. The recommended content and particle size of CB are 2% and 2.6 μm. This study refines the complex effects of CB on asphalt properties, providing a reference for determining the size and content of CB in asphalt modification.

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Gere, Sisay, Yemane Berhane et Alemayehu Worku. « Comparison of Chest-to-Back Skin-to-Skin Contact and Chest-to-Chest Skin-to-Skin Contact on the Risk of Oxygen Desaturation and Change in Heart Rate in Low Birth Weight and/or Premature Babies : A Randomized Controlled Clinical Trial ». International Journal of Pediatrics 2021 (8 décembre 2021) : 1–7. http://dx.doi.org/10.1155/2021/7196749.

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Chest-to-chest (CC) skin-to-skin contact (SSC) is a widely used method of SSC to prevent low birth weight (LBW) and/or premature babies with the risk of hypothermia. However, very recently, a study has also shown that the chest-to-back (CB) SSC is also useful for such a purpose. It is also evident that CC SSC enhances the cardiorespiratory performance of LBW and/or premature babies from the risk of cold stress. However, whether babies kept in CB SSC have the risk of clinically relevant decreases of oxygen saturation or critical changes of the baby heart rate comparing the two SSC methods has been studied hardly. Thus, we assessed the risk of oxygen desaturation and changes in babies’ heart rate among LBW and/or premature babies kept in CB SSC compared to the standard. In this study, we enrolled 46 LBW and/or premature babies born between 32 and 37 completed weeks of gestation. We used a parallel-group randomized controlled clinical trial. Peripheral arterial blood oxygen saturation (SpO2) and heart rate (HR) were measured using an OxiMaxN-600X Pulse Oximeter. We transformed these measurements into stability of the cardiorespiratory system in premature infant (SCRIP) scores. We applied a generalized estimating equation model to analyze the data. No statistically significant difference was observed between babies kept in CB SSC compared to babies kept in CC SSC in either blood oxygen saturation or heart rate ( P > 0.05 ). Thus, the CB SSC can be used as one possible way to care for LBW and preterm babies in the kangaroo mother care. We suggest more studies before scaling up the approach in routine care.

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Alshammari, Bushra, Helen Noble, Helen McAneney, Farhan Alshammari et Peter O’Halloran. « Factors Associated with Burden in Caregivers of Patients with End-Stage Kidney Disease (A Systematic Review) ». Healthcare 9, n^o 9 (14 septembre 2021) : 1212. http://dx.doi.org/10.3390/healthcare9091212.

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Background: Caring for a patient with end-stage kidney disease (ESKD) is highly stressful and can impact negatively on the physical and psychological well-being of caregivers. To accurately assess caregiver burden (CB), health care providers (HCPs) need to identify characteristics associated with an increase in CB. Aim: The aim of this review is to explore CB in caregivers of adult patients with ESKD and to identify characteristics associated with any increase in CB. Method: A comprehensive literature search was completed using five electronic databases. Medline, Embase, CINHAL, PsycINFO, and Scopus. The Joanna Briggs Institute checklist (JBI) was used to quality appraise full text papers included in the review. No time limit for the date of publication of studies was employed, to enable the inclusion of more extensive literature. Results: A total of 38 relevant studies from 18 countries were identified and included in the review. A variety of patient and caregiver factors can impact positively or negatively on CB, including socio-demographic factors of patients and caregivers, disease-related factors, situational and relational factors, environmental factors, and psychological factors. Conclusion: This review provides awareness to HCPs of the important factors associated with CB, when assessing or targeting interventions for caregivers experiencing burden.

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Zhang, Shuwen, Zheping Yu, Li Sun, Haiying Ren, Xiliang Zheng, Senmiao Liang et Xingjiang Qi. « An overview of the nutritional value, health properties, and future challenges of Chinese bayberry ». PeerJ 10 (4 mars 2022) : e13070. http://dx.doi.org/10.7717/peerj.13070.

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Chinese bayberry (CB) is among the most popular and valuable fruits in China owing to its attractive color and unique sweet/sour taste. Recent studies have highlighted the nutritional value and health-related benefits of CB. CB has special biological characteristics of evergreen, special aroma, dioecious, nodulation, nitrogen fixation. Moreover, the fruits, leaves, and bark of CB plants harbor a number of bioactive compounds including proanthocyanidins, flavonoids, vitamin C, phenolic acids, and anthocyanins that have been linked to the anti-cancer, anti-oxidant, anti-inflammatory, anti-obesity, anti-diabetic, and neuroprotective properties and to the treatment of cardiovascular and cerebrovascular diseases. The CB fruits have been used to produce a range of products: beverages, foods, and washing supplies. Future CB-related product development is thus expected to further leverage the health-promoting potential of this valuable ecological resource. The present review provides an overview of the botanical characteristics, processing, nutritional value, health-related properties, and applications of CB in order to provide a foundation for further research and development.

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Peterson, Steven C., et Nirmal Joshee. « Co-milled silica and coppiced wood biochars improve elongation and toughness in styrene-butadiene elastomeric composites while replacing carbon black ». Journal of Elastomers & ; Plastics 50, n^o 8 (21 janvier 2018) : 667–76. http://dx.doi.org/10.1177/0095244317753653.

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Carbon black (CB) is a petroleum by-product with a million ton market in the US tire industry. Finding renewable substitutes for CB reduces dependence on oil and alleviates global warming. Biochar is a renewable source of carbon that has been studied previously as a replacement for CB in styrene-butadiene rubber (SBR) composites. However, biochar typically has lower carbon content, higher ash content, and larger particle size, which are all significant detractors to making biochar a viable drop-replacement for CB. In this study, high carbon and low ash biochars made from fast-growing Paulownia elongata and Populus tremuloides were co-milled with small amounts of silica in order to reduce the particle size, and the biochar/silica blends were then used to partially replace CB in SBR composites. Using this method both Paulownia and poplar biochars were able to replace 30% of the CB filler and improve elongation and toughness with virtually no loss of tensile strength, compared to the 100% CB-filled control composite.

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Eskola, Mikko, Sari Rekunen, Sari Mottonen, Pekka Aroviita et Riitta Kekomaki. « Screening for the Megakaryocytopoietic Potential of Cord Blood Units. » Blood 108, n^o 11 (16 novembre 2006) : 5215. http://dx.doi.org/10.1182/blood.v108.11.5215.5215.

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Abstract OBJECTIVE: Delayed platelet engraftment is a common problem after hematopoietic stem cell transplantation. However, although aiming at high quality, the megakaryocytopoietic potential of cord blood (CB) units is not routinely studied in CB banks. In this study, a simple method for the evaluation of the megakaryocytic growth of unfrozen CB units was designed. The results were compared with cell characteristics of the units, including mean platelet volume (MPV) and platelet concentration in unprocessed CB as possible markers of thrombopoietic potential. MATERIALS & METHODS: Buffy coat (BC) samples from 24 randomly selected CB units were cultured on two double-chamber slides per unit in a semisolid assay designed to support megakaryocytic cells (MegaCult-C, StemCell Technologies Inc., Vancouver, Canada). After 13 days, the cells were fixed and stained using a monoclonal CD41 antibody and the alkaline-phosphatase anti-alkaline-phosphatase technology. Based on the appearance of megakaryocytic colonies, the CB units were scored on a scale 0–3 by three independent investigators. The scores were compared with CB bank data of the same units. The nonparametric Kendall coefficient of concordance (W) and simple linear regression were used for statistics. RESULTS: The study sample was confirmed representative of all CB units processed during the same time period. All CB units received a mean score of at least 0.7, indicating megakaryocytic growth. The scores given by the three investigators appeared similar and a high concordance was observed (W= 0.91; p < 0.0001), although the distribution of scores varied slightly between the investigators. Using simple linear regression, a clear yet not statistically significant correlation was discovered between the megakaryocyte (MK) score and the volume proportion of platelets in unprocessed CB (“plateletcrit”), defined as MPV × platelet concentration.A correlation (although not statistically significant) was also observed between the MK score and both MPV and platelet concentration. MK score and markers of thrombopoiesis (n=24) Mean (Range) R p* *Two sided Plateletcrit, % 0.23 (0.13–0.35) −0.21 0.32 MPV, fl 8.9 (8.0–9.7) 0.27 0.20 Platelet concentration, 109/l 258 (136–374) −0.25 0.23 In addition, a negative correlation between MPV and platelet concentration was discovered (R= −0.35; p= 0.091). No significant correlation was observed between the MK score and total colony-forming unit (CFU) number, total CD34+ cells or total nucleated cells (TNC) in BC. MK score and CB unit cell contents (n=24) Mean (Range) R p* *Two sided Total CFU, 106 2.4 (0.8–4.5) 0.004 0.98 Total CD34+ cells, 106 5.4 (1.4–11.5) 0.04 0.84 TNC, 107 124 (69.4–212) 0.13 0.54 CONCLUSIONS: As the megakaryocytopoietic potential of a CB unit does not necessarily correlate with data used to select units for banking and transplantation, screening for this potential may be of clinical significance. The screening method used in this study was simple and required no extra sample from the CB unit; however, more studies are needed to identify the best procedure for a routine setting. The associations observed between the MK score, MPV and platelet concentration may reflect the autoregulation of thrombopoiesis as well as the reliability of the screening procedure. The development of screening methods for the megakaryocytopoietic potential of a CB unit may be an important step in improving platelet engraftment after transplantation.

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Termignoni-Garcia, Flavia, Matthew I. M. Louder, Christopher N. Balakrishnan, Lauren O’Connell et Scott V. Edwards. « Prospects for sociogenomics in avian cooperative breeding and parental care ». Current Zoology 66, n^o 3 (4 décembre 2019) : 293–306. http://dx.doi.org/10.1093/cz/zoz057.

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Abstract For the last 40 years, the study of cooperative breeding (CB) in birds has proceeded primarily in the context of discovering the ecological, geographical, and behavioral drivers of helping. The advent of molecular tools in the early 1990s assisted in clarifying the relatedness of helpers to those helped, in some cases, confirming predictions of kin selection theory. Methods for genome-wide analysis of sequence variation, gene expression, and epigenetics promise to add new dimensions to our understanding of avian CB, primarily in the area of molecular and developmental correlates of delayed breeding and dispersal, as well as the ontogeny of achieving parental status in nature. Here, we outline key ways in which modern -omics approaches, in particular genome sequencing, transcriptomics, and epigenetic profiling such as ATAC-seq, can be used to add a new level of analysis of avian CB. Building on recent and ongoing studies of avian social behavior and sociogenomics, we review how high-throughput sequencing of a focal species or clade can provide a robust foundation for downstream, context-dependent destructive and non-destructive sampling of specific tissues or physiological states in the field for analysis of gene expression and epigenetics. -Omics approaches have the potential to inform not only studies of the diversification of CB over evolutionary time, but real-time analyses of behavioral interactions in the field or lab. Sociogenomics of birds represents a new branch in the network of methods used to study CB, and can help clarify ways in which the different levels of analysis of CB ultimately interact in novel and unexpected ways.

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Jan, Pey-Shynan, Hsu-Yuang Huang et Hueih-Min Chen. « Expression of a Synthesized Gene Encoding Cationic Peptide Cecropin B in Transgenic Tomato Plants Protects against Bacterial Diseases ». Applied and Environmental Microbiology 76, n^o 3 (4 décembre 2009) : 769–75. http://dx.doi.org/10.1128/aem.00698-09.

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ABSTRACT The cationic lytic peptide cecropin B (CB), isolated from the giant silk moth (Hyalophora cecropia), has been shown to effectively eliminate Gram-negative and some Gram-positive bacteria. In this study, the effects of chemically synthesized CB on plant pathogens were investigated. The S50s (the peptide concentrations causing 50% survival of a pathogenic bacterium) of CB against two major pathogens of the tomato, Ralstonia solanacearum and Xanthomonas campestris pv. vesicatoria, were 529.6 μg/ml and 0.29 μg/ml, respectively. The CB gene was then fused to the secretory signal peptide (sp) sequence from the barley α-amylase gene, and the new construct, pBI121-spCB, was used for the transformation of tomato plants. Integration of the CB gene into the tomato genome was confirmed by PCR, and its expression was confirmed by Western blot analyses. In vivo studies of the transgenic tomato plant demonstrated significant resistance to bacterial wilt and bacterial spot. The levels of CB expressed in transgenic tomato plants (∼0.05 μg in 50 mg of leaves) were far lower than the S50 determined in vitro. CB transgenic tomatoes could therefore be a new mode of bioprotection against these two plant diseases with significant agricultural applications.

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Reggio, Patricia H. « Ligand-Ligand and Ligand-Receptor Approaches to Modeling the Cannabinoid CB₁ and CB₂ Receptors : Achievements and Challenges ». Current Medicinal Chemistry 6, n^o 8 (août 1999) : 665–83. http://dx.doi.org/10.2174/0929867306666220401124434.

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The cannabinoid CB<sub>1</sub> and CB<sub>1</sub> receptors belong to the super family of G protein-coupled receptors. Antagonists for each receptor sub type, as well as four structural classes of agonists that bind to both receptors, have been identified. In the absence of an experimentally determined structure for each of these two receptors, computational molecular modeling approaches have been employed to begin to probe structure-function rela tionships. Molecular modeling studies have been approached from two perspectives: calculations involving only ligands (Ligand-Ligand Approach) or calculations of the interaction of a ligand with its receptor macromolecule (Ligand-Receptor Approach) [49]. The Ligand-Ligand Approach does not directly consider the structure of the ligand binding site, but attempts to infer information about this site from a correlation between experimentally determined biological activities and the structural and electronic features of a series of small molecules. Ligand-Ligand Approaches result in development of pharmacophore models. Although closer to the event of interest, the study of the binding of a ligand to its receptor is less common because it requires a working knowledge of the receptor structure [54]. Mutation/ chimera studies, as well as structure activity relationships can be used to test models developed in a Ligand-Receptor Approach. This review considers both Ligand-Ligand and Ligand-Receptor computational studies of the CB1 and CB2 receptors. Challenges for further modeling studies are also identified.

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Semmel, Eric S., Vonetta M. Dotson, Thomas G. Burns, William T. Mahle et Tricia Z. King. « Posterior Cerebellar Volume and Executive Function in Young Adults With Congenital Heart Disease ». Journal of the International Neuropsychological Society 24, n^o 9 (30 mai 2018) : 939–48. http://dx.doi.org/10.1017/s1355617718000310.

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AbstractObjectives: As the number of adolescents and young adults (AYAs) surviving congenital heart disease (CHD) grows, studies of long-term outcomes are needed. CHD research documents poor executive function (EF) and cerebellum (CB) abnormalities in children. We examined whether AYAs with CHD exhibit reduced EF and CB volumes. We hypothesized a double dissociation such that the posterior CB is related to EF while the anterior CB is related to motor function. We also investigated whether the CB contributes to EF above and beyond processing speed. Methods: Twenty-two AYAs with CHD and 22 matched healthy controls underwent magnetic resonance imaging and assessment of EF, processing speed, and motor function. Volumetric data were calculated using a cerebellar atlas (SUIT) developed for SPM. Group differences were compared with t tests, relationships were tested with Pearson’s correlations and Fisher’s r to z transformation, and hierarchical regression was used to test the CB’s unique contributions to EF. Results: CHD patients had reduced CB total, lobular, and white matter volume (d=.52–.99) and poorer EF (d=.79–1.01) compared to controls. Significant correlations between the posterior CB and EF (r=.29–.48) were identified but there were no relationships between the anterior CB and motor function nor EF. The posterior CB predicted EF above and beyond processing speed (ps<.001). Conclusions: This study identified a relationship between the posterior CB and EF, which appears to be particularly important for inhibitory processes and abstract reasoning. The unique CB contribution to EF above and beyond processing speed alone warrants further study. (JINS, 2018, 24, 939–948)

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Nitzsche, Peter J., C. A. Storlie, W. P. Cowgill et W. Tietjen. « INFLUENCE OF SOIL TENSION ON TOMATO FRUIT CRACKING ». HortScience 27, n^o 6 (juin 1992) : 663e—663. http://dx.doi.org/10.21273/hortsci.27.6.663e.

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Fruit cracking in tomatoes is a serious problem, particularly when trellis culture is used. Past studies indicate that fruit cracking is associated with fluctuating soil moisture levels. Soil moisture variations are influenced by irrigation practices, and an irrigation regime employing frequent applications of water will lessen variations in soil moisture. A field study was initiated to study the effect of trickle irrigation regime on fruit cracking in `Celebrity' tomatoes (Lycopersicon esculentum Mill). In the three treatments used, soil was allowed to dry to 10-20, 50-60, and 100-110 centibars of tension, respectively, between watering and then was irrigated to field capacity. These tension levels corresponded with soil moisture levels of field capacity (10-20 cb), 20% of available water depleted (50-60 cb), and 40% of available water depleted (100-110 cb). Yield measurements indicated that the driest treatment (100-110 cb) significantly reduced the percent of radially cracked fruit. This treatment also significantly lowered the total yield, in terms of both fruit number and weight. There was no significant effect, however, on marketable fruit yield due to irrigation treatments. Further field studies are required to determine the optimum irrigation program to reduce fruit cracking.

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Chen, Zhou, Junfeng Hu, Jiajun Ju et Tairong Kuang. « Fabrication of Poly(butylene succinate)/Carbon Black Nanocomposite Foams with Good Electrical Conductivity and High Strength by a Supercritical CO2 Foaming Process ». Polymers 11, n^o 11 (10 novembre 2019) : 1852. http://dx.doi.org/10.3390/polym11111852.

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Lightweight, high-strength and electrically conductive poly(butylene succinate) (PBS)/ carbon black (CB) nanocomposite foams with a density of 0.107–0.344 g/cm3 were successfully fabricated by a solid-state supercritical CO2 (ScCO2) foaming process. The morphology, thermal and dynamic mechanical properties, and rheological behavior of the PBS/CB nanocomposites were studied. The results indicate that the CB nanofiller was well dispersed in the PBS matrix and the presence of a proper CB nanofiller can accelerate the rate of crystallization, improve the thermal stability, enhance the stiffness, and increase the complex viscosity of PBS/CB nanocomposites. These improved properties were found to play an important role in the foaming process. The results from foaming experiments showed that the PBS/CB nanocomposite foams had a much smaller cell size, a higher cell density, and a more uniform cell morphology as compared to neat PBS foams. Furthermore, the PBS/CB nanocomposite foams also possessed low density (0.107–0.344 g/cm3), good electrical conductivity (~0.45 S/cm at 1.87 vol % CB loading), and improved compressive strength (108% increase), which enables them to be used as lightweight and high-strength functional materials.

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Peterson, Steven C. « Silica-Milled Paulownia Biochar as Partial Replacement of Carbon Black Filler in Natural Rubber ». Journal of Composites Science 3, n^o 4 (13 décembre 2019) : 107. http://dx.doi.org/10.3390/jcs3040107.

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Carbon black (CB) has been the dominant filler in the tire industry for decades. The demand for this petroleum byproduct is ever increasing, although petroleum markets can be volatile due to geopolitical issues. Finding sustainable, renewable substitutes for CB reduces the dependence on petroleum. Biochar is a renewable source of carbon that was studied as a potential CB replacement filler in styrene–butadiene rubber (SBR) composites, but little has been done in terms of natural rubber (NR). In this work, biochar made from fast-growing Paulownia elongata was co-milled with small amounts of silica in order to reduce the larger particle size typical with biochar respective to CB. The resulting silica-milled Paulownia biochar (PB) was then used to replace CB in natural rubber (NR) composites. By using this method to make natural rubber composites with 30% total filler, half of the CB was fully replaced with silica-milled biochar with very little loss (<6%) of tensile strength, and equal or better elongation and toughness compared to the 100% CB-filled control composite.

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Wissner, Erik. « Ablation of atrial fibrillation using the fourth-generation cryoballoon Arctic Front Advance PRO ». Future Cardiology 17, n^o 1 (janvier 2021) : 81–87. http://dx.doi.org/10.2217/fca-2020-0066.

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The cryoballoon (CB) is a popular ablation technology used for pulmonary vein isolation. The fourth-generation CB, Arctic Front Advance PRO features a 40% shorter distal tip but retains the internal design from its second-generation predecessor. The Arctic Front Advance PRO and the second-generation CB demonstrated similar thermodynamic characteristics in a computational model. Several observational and retrospective studies established the acute safety and efficacy of the Arctic Front Advance PRO. Real-time electrical isolation was observed in 75–85% of pulmonary veins targeted with the Arctic Front Advance PRO resulting in shorter fluoroscopy and procedure times.

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Blain, Grégory M., Curtis A. Smith, Kathleen S. Henderson et Jerome A. Dempsey. « Contribution of the carotid body chemoreceptors to eupneic ventilation in the intact, unanesthetized dog ». Journal of Applied Physiology 106, n^o 5 (mai 2009) : 1564–73. http://dx.doi.org/10.1152/japplphysiol.91590.2008.

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We used extracorporeal perfusion of the reversibly isolated carotid sinus region to determine the effects of specific carotid body (CB) chemoreceptor inhibition on eupneic ventilation (V̇i) in the resting, awake, intact dog. Four female spayed dogs were studied during wakefulness when CB was perfused with 1) normoxic, normocapnic blood; and 2) hyperoxic (>500 mmHg), hypocapnic (∼20 mmHg) blood to maximally inhibit the CB tonic activity. We found that CB perfusion per se (normoxic-normocapnic) had no effect on V̇i. CB inhibition caused marked reductions in V̇i (−60%, range 49–80%) and inspiratory flow rate (−58%, range 44–87%) 24–41 s following the onset of CB perfusion. Thereafter, a partial compensatory response was observed, and a steady state in V̇i was reached after 50–76 s following the onset of CB perfusion. This steady-state tidal volume-mediated hypoventilation (∼31%) coincided with a significant reduction in mean diaphragm electromyogram (−24%) and increase in mean arterial pressure (+12 mmHg), which persisted for 7–25 min until CB perfusion was stopped, despite a substantial increase in CO2 retention (+9 Torr, arterial Pco2) and systemic respiratory acidosis. We interpret these data to mean that CB chemoreceptors contribute more than one-half to the total eupneic drive to breathe in the normoxic, intact, awake animal. We speculate that this CB contribution consists of both the normal tonic sensory input from the CB chemoreceptors to medullary respiratory controllers, as well as a strong modulatory effect on central chemoreceptor responsiveness to CO2.

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Boruczkowski, Dariusz, Josep-Maria Pujal et Izabela Zdolińska-Malinowska. « Autologous Cord Blood in Children with Cerebral Palsy : A Review ». International Journal of Molecular Sciences 20, n^o 10 (16 mai 2019) : 2433. http://dx.doi.org/10.3390/ijms20102433.

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The aim of this narrative review is to report on the current knowledge regarding the clinical use of umbilical cord blood (CB) based on articles from PubMed and clinical trials registered on ClinicalTrials.gov. An increasing amount of evidence suggests that CB may be used for both early diagnostics and treatment of cerebral palsy. The acidity of CB and its biochemical parameters, including dozens of cytokines, growth factors, and other metabolites (such as amino acids, acylcarnitines, phosphatidylcholines, succinate, glycerol, 3-hydroxybutyrate, and O-phosphocholine) are predictors of future neurodevelopment. In addition, several clinical studies confirmed the safety and efficacy of CB administration in both autologous and allogeneic models, including a meta-analysis of five clinical trials involving a total of 328 participants. Currently, nine clinical trials assessing the use of autologous umbilical CB in children diagnosed with hypoxic-ischemic encephalopathy or cerebral palsy are in progress. The total population assessed in these trials exceeds 2500 patients.

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Zelazo, Philip David, Jacob E. Anderson, Jennifer Richler, Kathleen Wallner-Allen, Jennifer L. Beaumont, Kevin P. Conway, Richard Gershon et Sandra Weintraub. « NIH Toolbox Cognition Battery (CB) : Validation of Executive Function Measures in Adults ». Journal of the International Neuropsychological Society 20, n^o 6 (24 juin 2014) : 620–29. http://dx.doi.org/10.1017/s1355617714000472.

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AbstractThis study describes psychometric properties of the NIH Toolbox Cognition Battery (NIHTB-CB) executive function measures in an adult sample. The NIHTB-CB was designed for use in epidemiologic studies and clinical trials for ages 3 to 85. A total of 268 self-described healthy adults were recruited at four university-based sites, using stratified sampling guidelines to target demographic variability for age (20–85 years), gender, education and ethnicity. The NIHTB-CB contains two computer-based instruments assessing executive function: the Dimensional Change Card Sort (a measure of cognitive flexibility) and a flanker task (a measure of inhibitory control and selective attention). Participants completed the NIHTB-CB, corresponding gold standard convergent and discriminant measures, and sociodemographic questionnaires. A subset of participants (N=89) was retested 7 to 21 days later. Results reveal excellent sensitivity to age-related changes during adulthood, excellent test–retest reliability, and adequate to good convergent and discriminant validity. The NIH Toolbox EF measures can be used effectively in epidemiologic and clinical studies. (JINS, 2014, 20, 1–10)

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Kendler, K. S., C. J. Patrick, H. Larsson, C. O. Gardner et P. Lichtenstein. « Genetic and environmental risk factors in males for self-report externalizing traits in mid-adolescence and criminal behavior through young adulthood ». Psychological Medicine 43, n^o 10 (1 février 2013) : 2161–68. http://dx.doi.org/10.1017/s003329171300007x.

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BackgroundExternalizing traits or behaviors are typically assessed by self-report scales or criminal records. Few genetically informative studies have used both methods to determine whether they assess the same genetic or environmental risk factors.MethodWe examined 442 male Swedish twin pairs with self-reported externalizing behaviors at age 16–17 years [externalizing traits (EXT), self-reported delinquency (SRD), impulsivity (IMP), grandiosity (GRD) and callousness (CLS)] and criminal behavior (CB) from the National Suspect Registry from age 13 to 25 years. Multivariate structural equation modeling was conducted with Mx.ResultsThe best-fit model contained one genetic, one shared environmental and two non-shared environmental common factors, and variable specific genetic and non-shared environmental factors. The risk for CB was influenced substantially by both genetic (a2 = 0.48) and familial–environmental factors (c2 = 0.22). About one-third of the genetic risk for CB but all of the shared environmental risk was indexed by the self-report measures. The degree to which the individual measures reflected genetic versus familial–environmental risks for CB varied widely. GRD and CLS were correlated with CB mainly through common genetic risk factors. SRD and CB covaried largely because of shared familial–environmental factors. For EXT and IMP, observed correlations with CB resulted in about equal parts from shared genetic and shared familial–environmental factors.ConclusionsIn adolescence, measures of grandiose and callous temperament best tap the genetic liability to CB. Measures of antisocial behaviors better index familial–environmental risks for CB. A substantial proportion of the genetic risk to CB was not well reflected in any of the self-report measures.

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Vivell, Maj-Britt, Vanessa Opladen, Silja Vocks et Andrea S. Hartmann. « Short-term functions and long-term consequences of checking behavior as a transdiagnostic phenomenon : protocol for a systematic review ». BMJ Open 12, n^o 4 (avril 2022) : e056732. http://dx.doi.org/10.1136/bmjopen-2021-056732.

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IntroductionChecking behaviour (CB) occurs in various mental health problems. Cognitive-behavioural models for these mental disorders share similar theoretical assumptions. Thus, they postulate a negative reinforcing effect of CB by reducing negative affect (ie, anxiety) and a maintenance of the pathology due to a lack of reality testing of concerns. This paper details methods for a systematic review that will be conducted to synthesise empirical evidence testing these theoretical assumptions across obsessive–compulsive, generalised anxiety, eating, body dysmorphic and illness anxiety disorder. The results are expected to foster our understanding of the mechanisms of action underlying CB, which is of high clinical relevance. Depending on whether or not the findings confirm the model assumptions regarding CB, the focus of treatments would need to be intensified or modified.Methods and analysisWe will search PsycINFO, PubMed, PSYNDEX and Scopus for studies investigating the emotional state in which CB is being used as well as the immediate and longer-term effects of CB on cognitive and emotional measures in clinical and analogue samples. The selection process, data extraction and quality assessment of included studies will be performed by two independent reviewers. In the case of inconsistencies, a third reviewer will be involved. Study results will be reported in a narrative synthesis.Ethics and disseminationEthics approval will not be required as this is a protocol for systematic review. The results are mainly disseminated through peer-reviewed publications.PROSPERO registration numberCRD42021238835.

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Ismail, S., S. A. Abu, R. Rezaur et H. Sinin. « Biodiesel Production from Castor Oil and Its Application in Diesel Engine ». ASEAN Journal on Science and Technology for Development 31, n^o 2 (20 décembre 2014) : 90. http://dx.doi.org/10.29037/ajstd.18.

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In this study, the optimum biodiesel conversion from crude castor oil to castor biodiesel (CB) through transesterification method was investigated. The base catalyzed transesterification under different reactant proportion such as the molar ratio of alcohol to oil and mass ratio of catalyst to oil was studied for optimum production of castor biodiesel. The optimum condition for base catalyzed transesterification of castor oil was determined to be 1:4.5 of oil to methanol ratio and 0.005:1 of potassium hydroxide to oil ratio. The fuel properties of the produced CB such as the calorific value, flash point and density were analyzed and compared to conventional diesel. Diesel engine performance and emission test on different CB blends proved that CB was suitable to be used as diesel blends. CB was also proved to have lower emission compared to conventional diesel.

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Singh, Rashmi, et J. K. Nayak. « Life stressors and compulsive buying behaviour among adolescents in India ». South Asian Journal of Global Business Research 4, n^o 2 (3 août 2015) : 251–74. http://dx.doi.org/10.1108/sajgbr-08-2014-0054.

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Purpose – The compulsive buying (CB)behaviour has become topics of increasing interest to researchers and policy makers, particularly because researches have shown that it can influence consumer behaviour and well-being. However, a clear picture of how this phenomenon arises has proven elusive. Using the adolescents perceived level of stress as an integrative framework, the purpose of this paper is to derive hypotheses from two theoretical perspectives (the stress and CB behaviour), and uses a survey of adolescents (15-18) year in India to test the hypotheses. Design/methodology/approach – The present study is the first to experimentally manipulate important stressors in the lives of adolescents, i.e. familial and non-familial; and measures its impact on CB among a sample of 15-18-year old adolescents. Next, the authors investigate the relationship between CB and post-purchase regret and then whether gender moderates the stress-CB relationship. Findings – The present study finds that adolescents increasingly turn to CB in an attempt to cope with heightened levels of stress due to familial and non-familial factors. Surprisingly, findings reveal that non-familial factors are not a major source of stress among adolescents. Gender was not found to moderate stress-CB relationship. Both boys and girls were found to respond to higher levels of stress with higher incidences of CB. Results suggest that CB behaviour is a common coping strategy for adolescents from both genders. The findings indicate that one’s experiences and circumstances in adolescence are related to their CB behaviour, thus a framework has been used to elucidate them, have important implications for theory and practice. Originality/value – The study makes some inimitable and significant contributions to the literature. It portrays one of few studies to investigate CB during adolescence period – a hard to reach population. Here authors experimentally manipulate stress levels to investigate its impact on CB. The study’s findings in regard to gender’s impact on the stress-CB relationship suggest that CB begins during adolescence period and is a common coping strategy for both boys and girls.

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Sithornkul, Sarawuth, et Poonsub Threepopnatkul. « Control of Mechanical Properties and Permeability of Electrospun Natural Rubber with Different Composite Systems ». Advanced Materials Research 93-94 (janvier 2010) : 619–22. http://dx.doi.org/10.4028/www.scientific.net/amr.93-94.619.

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The electrospun natural rubber (NR) with two different components namely: acrylonitrile butadiene styrene (ABS) and carbon black (CB) have been extensively studied. The main objective was to investigate the mechanical properties and permeability dependency of NR/ABS and NR/CB as well as its contents. NR/CB was compounded by torque rheometer (Brabender) while ABS was dissolved with NR using tetrahydrofuran (THF) as its solvent. Sulfur was used as the vulcanizing agent in both systems. Mechanical properties were evaluated by universal testing machine and permeability was observed by water vapour permeability. The optimum conditions for electrospun NR/ABS and NR/CB non-woven mats were as follows: flow rate 30 ml/h, voltage 15 kV, collector distance 20 cm and collected on rotating circular plate at 1000 rpm. The results of mechanical properties showed that for electrospun NR/CB fiber membranes, the higher the CB loading it had, the lower its tensile strength and elongation it would be. Whilst electrospun NR/ABS fiber mats, the elongation behavior was affected by the ABS loading but not the tensile strength. For permeability, NR/CB was shown to possess relatively higher permeability than the NR/ABS non-woven mats.

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Miller, Kimberly J., Courtney L. Pollock, Brenda Brouwer et S. Jayne Garland. « Use of Rasch Analysis to Evaluate and Refine the Community Balance and Mobility Scale for Use in Ambulatory Community-Dwelling Adults Following Stroke ». Physical Therapy 96, n^o 10 (1 octobre 2016) : 1648–57. http://dx.doi.org/10.2522/ptj.20150423.

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AbstractBackgroundThe Community Balance and Mobility Scale (CB&M) is increasingly used to evaluate walking balance following stroke.ObjectiveThis study applied Rasch analysis to evaluate and refine the CB&M for use in ambulatory community-dwelling adults following stroke.MethodsThe CB&M content was linked to task demands and motor skill classifications. Rasch analysis was used to evaluate internal construct validity (structural validity) and refine the CB&M for use with ambulatory community-dwelling adults following stroke. The CB&M data were collected at 3 time points: at discharge from inpatient rehabilitation and at 6 and 12 months postdischarge (N=238). Rasch analysis evaluated scale dimensionality, item and person fit, item response bias, scoring hierarchy, and targeting. Disordered scoring hierarchy was resolved by collapsing scoring categories. Highly correlated and “misfitting” items were removed. Sensitivity to change was evaluated with standardized response means (SRMs) and one-way repeated-measures analysis of variance.ResultsThe CB&M was primarily linked to closed body transport task demands. Significant item-trait interaction, disordered scoring hierarchies, and multidimensionality were found. Scoring categories were collapsed in 15/19 items, and 5 misfitting items were removed. The resulting stroke-specific 14-item unidimensional CB&M (CB&MStroke) fit Rasch model expectations, with no item response bias, acceptable targeting (13% floor effects and 0% ceiling effects), and moderate-to-strong sensitivity to change at 6 months postdischarge (SRM=0.63; 95% confidence interval=−1.523, −0.142) and 12 months postdischarge (SRM=0.73; 95% confidence interval=−2.318, −0.760).LimitationsFindings are limited to a modest-sized sample of individuals with mild-to-moderate balance impairment following stroke.ConclusionsThe CB&MStroke shows promise as a clinical scale for measuring change in walking balance in ambulatory community-dwelling adults poststroke. Future studies are recommended in a larger sample to validate and further refine the scale for use in this clinical population.

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Lee, Byoung-Cheon, Ki-Hak Lee et Bo-Hyeun Wang. « Control Bifurcation Structure of Return Map Control in Chua's Circuit ». International Journal of Bifurcation and Chaos 07, n^o 04 (avril 1997) : 903–9. http://dx.doi.org/10.1142/s0218127497000704.

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We demonstrate that return map control and adaptive tracking can be used together to locate, stabilize, and track unstable periodic orbits (UPOs). Through bifurcation studies as a function of some control parameters of return map control, we observe the control bifurcation (CB) phenomenon which exhibits another route to chaos. Nearby an UPO there are a lot of driven periodic orbits (DPOs) along the CB route. DPOs are not embedded in the original chaotic attractor, but they are generated artificially by driving the system slightly in a direction with feedback control. Based on the CB phenomenon, our adaptive tracking algorithm searches for the location and the exact control condition of the UPO by minimizing feedback perturbations. We discuss the universality of the CB phenomenon and the possibility of immediate control which does not require much prior analysis of the system.

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Pandey, Achal, Srinivasarao Naik B, Shishir Sinha et B. Prasad. « Carbon Black Production from Various Sources by Thermal Cracking Method ». Energy Environment and Storage 2, n^o 3 (24 septembre 2022) : 1–8. http://dx.doi.org/10.52924/nsvq3567.

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Petroleum-based feedstock (PBFS) and Coal tar-based feedstock (CTBFS) were used for the synthesis of carbon black (CB) via the thermal cracking method named as Petroleum-based feedstock carbon black (PBFS-CB) and Coal tar-based feedstock carbon black (CTBFS-CB) in a furnace reactor at a temperature of 1800 °C, for utilizing industrial waste products. The obtained distinguished carbon black samples are characterized for determining functional groups, morphology, and surface area using advanced instruments. Further, investigated the physical and mechanical properties of obtained different CB samples were mixed into the natural rubber. The small cluster morphology is observed in CBs. There are slight changes in spectra peaks and there no significant new peaks are observed. The same minerals were observed at the same theta values in the XRD pattern corresponding to PBFS-CB and CTBFS-CB. The tensile strength, modulus 300%, and abrasion loss of samples into rubber were determined as per international ASTM standards. The results revealed that there are negotiable values observed in both samples due to minimal changes observed in the surface area of the CB samples. These samples can be used for various applications viz rubber reinforcement, conductivity agent, coloring agent, and ultraviolet screening agent etc.

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Vejmelková, Eva, Monika Čáchová et Jaroslava Koťátková. « Influence of Selected Pozzolanas on Basic Physical and Mechanical Properties of HSC ». Materials Science Forum 824 (juillet 2015) : 39–42. http://dx.doi.org/10.4028/www.scientific.net/msf.824.39.

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Crushed brick (CB) used in high strength concrete as partial replacement of cement is the subject of this paper. It is a waste material and so its exploitation is needed to be found. Concrete industry can be proper area as CB is a fine material and is pozzolanic active. Basic physical properties and mechanical properties were investigated. Open porosity and bulk density achieved the best values when 30% of cement was replaced by CB. Matrix density decreased with rising addition ratio. The values of compressive strength was the highest for 30% replacement level and with 60% addition ratio were not lower than for the reference mixture. The conclusion is, that according to studied parameters 30% of cement substituted by CB is the most profitable addition ratio.

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Mizuta, Keisuke, Makoto Okano, Takahiro Morimoto, Seisuke Ata et Shinichi Watanabe. « Strain-induced irreversible change of the conductive network in a rubber/carbon-black composite revealed by polarization-resolved terahertz dielectric spectroscopy ». Applied Physics Letters 121, n^o 2 (11 juillet 2022) : 024101. http://dx.doi.org/10.1063/5.0099975.

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The dielectric response during the deformation of a rubber composite filled with carbon black (CB) was studied by polarization-resolved terahertz spectroscopy, because the characterization of such responses can be used to reveal strain-induced irreversible changes in the electrical properties of a CB-filled rubber. During the first stretching-and-relaxation cycle, two characteristic behaviors were observed: strain-induced anisotropy and an irreversible reduction of the dielectric constants in the measured frequency range. To understand the origin of this result, we tried to reproduce the strain dependence of the dielectric function with a modified effective medium theory that accounts for the orientational distribution of the CB aggregates. From the dependence of the fitting parameters on the deformation condition, it was found that the reduction of the dielectric constants in the terahertz frequency range is mainly caused by the breakdown of the CB-based conductive network due to a dissociation of CB agglomerates. This finding indicates that polarization-resolved terahertz spectroscopy is a promising technique for the assessment of changes in the internal structure of CB fillers on the nanometer scale.

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Raju, Gunasunderi, Mohammad Khalid, Mahmoud M. Shaban et Baharin Azahari. « Preparation and Characterization of Eco-Friendly Spent Coffee/ENR50 Biocomposite in Comparison to Carbon Black ». Polymers 13, n^o 16 (20 août 2021) : 2796. http://dx.doi.org/10.3390/polym13162796.

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This study investigates the impact of spent coffee biochar (Biochar) compared to carbon black (CB) as a partial replacement for carbon black in epoxidized natural rubber (ENR). Particle size and elemental analysis were used to characterize the biochar and CB. Cure characteristics, tensile, thermal, and morphological properties on the effect of biochar and CB as filler were studied. It was found that incorporating 10 phr of spent coffee biochar could improve the composites’ tensile properties and thermal performance compared to carbon black. However, the addition of biochar significantly affects the maximum torque compared to CB and delays the vulcanization time. SEM study shows that biochar has a strong effect on the morphology of composite films. The FTIR graph reveals no substantial difference between compounds with biochar and CB. According to the thermal calorimetric study, the thermal stability of ENR-Biochar is higher than that of ENR-CB. Additionally, these findings suggest that the utilization of spent coffee as a sustainable biochar could be further explored, but little has been done in epoxidized natural rubber (ENR).

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