Journal articles: 'Core box'

1

Sun, Qing Zhou, Li Jin, Pu Qing Zhang, Zhong Kui Zhao, Jian Wang, and Jing Guang Yan. "The Process Adaptability Study under the Conditions of Reclaimed Clay Sand Variable System." Applied Mechanics and Materials 432 (September 2013): 11–15. http://dx.doi.org/10.4028/www.scientific.net/amm.432.11.

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This paper studies the process adaptability of reclaimed clay sand with core sand, and discovers that the reclaimed clay sand with furan resin self-setting sand can be used to mix the water-glass sand and hot core box sand; but it can not be used to mix the cold core box sand and coated sand. The reclaimed clay sand with water-glass sand can not be used to mix the hot core box sand, cold core box sand and coated sand; the reclaimed clay sand with hot core box sand can be used to mix the water-glass sand, cold core box sand and coated sand; the reclaimed clay sand with cold core box sand can be used to mix the water-glass sand, coated sand and hot core box sand. The reclaimed clay sand with coated sand can be used to mix the water-glass sand, but when it is used to mix the hot core box sand and cold core box sand, it can meet general requirements of the casting production; the completely reclaimed clay sand can not be used to mix the resin self-setting sand.

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McKeegan, Kenneth Scott, Charles Maurice Debieux, Séverine Boulon, Edouard Bertrand, and Nicholas James Watkins. "A Dynamic Scaffold of Pre-snoRNP Factors Facilitates Human Box C/D snoRNP Assembly." Molecular and Cellular Biology 27, no. 19 (July 16, 2007): 6782–93. http://dx.doi.org/10.1128/mcb.01097-07.

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ABSTRACT The box C/D small nucleolar RNPs (snoRNPs) are essential for the processing and modification of rRNA. The core box C/D proteins are restructured during human U3 box C/D snoRNP biogenesis; however, the molecular basis of this is unclear. Here we show that the U8 snoRNP is also restructured, suggesting that this may occur with all box C/D snoRNPs. We have characterized four novel human biogenesis factors (BCD1, NOP17, NUFIP, and TAF9) which, along with the ATPases TIP48 and TIP49, are likely to be involved in the formation of the pre-snoRNP. We have analyzed the in vitro protein-protein interactions between the assembly factors and core box C/D proteins. Surprisingly, this revealed few interactions between the individual core box C/D proteins. However, the novel biogenesis factors and TIP48 and TIP49 interacted with one or more of the core box C/D proteins, implying that they mediate the assembly of the pre-snoRNP. Consistent with this, we show that NUFIP bridges interactions between the core box C/D proteins in a partially reconstituted pre-snoRNP. Restructuring of the core complex probably reflects the conversion of the pre-snoRNP, where core protein-protein interactions are maintained by the bridging biogenesis factors, to the mature snoRNP.

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3

Fedoryszyn, A., and R. Dańko. "Examinations of Parameters Influencing the Outflow of Two Phase Air-Sand Stream from Machine Chamber and Core Box Filling in Shooting Process." Archives of Metallurgy and Materials 58, no. 3 (September 1, 2013): 903–6. http://dx.doi.org/10.2478/amm-2013-0097.

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Abstract The study investigates the key aspects involved in the flow of the air-sand stream from the machine chamber and in the core box filling in the core shooting and core blowing processes. The prevailing tendency to manufacture thin-walled castings with intricate channel structures has become the major determinant of castings quality and production rates. An important parameter of most core sand used in the shooting processes is the ability to eject from the machine chamber and the core-box filling capability. These properties are the key factors determining the feasibility of manufacturing intricate cores and the process efficiency. The research work outlined in this study focuses on establishing the performance criteria of core sand ejection from the machine chamber and of core box filling and sand compaction. The results given below were obtained for several new-generation core sand types, containing organic and inorganic binders, and designed to be used in hot-box, warm box and warm air processes.

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Ma, Xian Zhen, Wei Zhang, and Fu Rong Wang. "Improvement for Block Cipher Based on S-Box Reorganization." Applied Mechanics and Materials 543-547 (March 2014): 3516–19. http://dx.doi.org/10.4028/www.scientific.net/amm.543-547.3516.

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S-box is the core of block ciphers. Its cryptographic properties impact on the security of block ciphers directly. From S-box inherent weaknesses, this paper adopt Fractal theory, and put forward a method based on non S-box transformation to change the S-box using sequence, that is, using the sub-key of each round to determine the S-box sequence by Fractal theory, then the effects different keys in each encryption come true. The method improved encryption algorithm, enhanced encryption strength and increased the algorithms security.

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Fedoryszyn, A., J. Dańko, R. Dańko, M. Asłanowicz, T. Fulko, and A. Ościłowski. "Characteristic of Core Manufacturing Process with Use of Sand, Bonded by Ecological Friendly Nonorganic Binders." Archives of Foundry Engineering 13, no. 3 (September 1, 2013): 19–24. http://dx.doi.org/10.2478/afe-2013-0052.

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Abstract Mechanization of the process of core making with the use of inorganic and organic binders is based, almost solely, on core blowing machines. Presently the core blowing machines are equipped with tools and devices that allow for application of different technologies of core making. Cold-box, hot-box and warm-air technologies require that core blowing machines shall be additionally equipped with either core-box pre-heating system or gas purging and neutralization system, or hot air purging systems. Considering the possibility of using varied, the most advantageous technologies of core making, the production of universal core blowing machines equipped with replaceable devices has been undertaken in Poland. The universal core blowing systems allow for mechanization of core making process also with the use of sand, bonded by modern, eco-friendly binder systems. The paper presents selected results-based evaluation of core blowing process showing the scope of conducted design and implementation works.

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Dańko, R., J. Dańko, A. Burbelko, and M. Skrzyński. "Core Blowing Process - Assessment of Core Sands Properties and Preliminary Model Testing." Archives of Foundry Engineering 14, no. 1 (March 1, 2014): 25–28. http://dx.doi.org/10.2478/afe-2014-0006.

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Abstract The effects of filling the core box cavity and sand compaction in processes of core production by blowing methods (blowing, shooting) depend on several main factors. The most important are: geometrical parameters of cavity and complexity of its shape, number, distribution and shape of blowing holes feeding sands as well as the venting of a technological cavity. Values of individual parameters are selected according to various criteria, but mostly they should be adjusted to properties of the applied core sand. Various methods developed by several researchers, including the authors own attempts, allow to assess core sands properties on the basis of special technological tests projecting the process into a laboratory scale. The developed criteria defining a degree or a filling ability factor provide a better possibility of assessing the core sand behavior during flowing and core box filling, which indicate the value and structure of the obtained compacting decisive - after hardening - for strength and permeability. The mentioned above aspects are analyzed - on the basis of authors’ own examinations - in the hereby paper.

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7

Ni, Changjiang, Gaochun Lu, Tao Jing, and Junjiao Wu. "Flow Dynamic Analysis of Core Shooting Process through Experiment and Multiphase Modeling." Advances in Materials Science and Engineering 2016 (2016): 1–12. http://dx.doi.org/10.1155/2016/2317180.

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Core shooting process is the most widely used technique to make sand cores and it plays an important role in the quality of sand cores as well as the manufacture of complicated castings in metal casting industry. In this paper, the flow behavior of sand particles in the core box was investigated synchronously with transparent core box, high-speed camera, and pressure measuring system. The flow pattern of sand particles in the shooting head of the core shooting machine was reproduced with various colored core sand layers. Taking both kinetic and frictional stress into account, a kinetic-frictional constitutive correlation was established to describe the internal momentum transfer in the solid phase. Two-fluid model (TFM) simulations with turbulence model were then performed and good agreement was achieved between the experimental and simulation results on the flow behavior of sand particles in both the shooting head and the core box. Based on the experimental and simulation results, the flow behavior of sand particles in the core box, the formation of “dead zone” in the shooting head, and the effect of drag force were analyzed in terms of sand volume fraction (αs), sand velocity (Vs), and pressure variation (P).

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8

Rudolph, Markus G., and Dagmar Klostermeier. "When core competence is not enough: functional interplay of the DEAD-box helicase core with ancillary domains and auxiliary factors in RNA binding and unwinding." Biological Chemistry 396, no. 8 (August 1, 2015): 849–65. http://dx.doi.org/10.1515/hsz-2014-0277.

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Abstract DEAD-box helicases catalyze RNA duplex unwinding in an ATP-dependent reaction. Members of the DEAD-box helicase family consist of a common helicase core formed by two RecA-like domains. According to the current mechanistic model for DEAD-box mediated RNA unwinding, binding of RNA and ATP triggers a conformational change of the helicase core, and leads to formation of a compact, closed state. In the closed conformation, the two parts of the active site for ATP hydrolysis and of the RNA binding site, residing on the two RecA domains, become aligned. Closing of the helicase core is coupled to a deformation of the RNA backbone and destabilization of the RNA duplex, allowing for dissociation of one of the strands. The second strand remains bound to the helicase core until ATP hydrolysis and product release lead to re-opening of the core. The concomitant disruption of the RNA binding site causes dissociation of the second strand. The activity of the helicase core can be modulated by interaction partners, and by flanking N- and C-terminal domains. A number of C-terminal flanking regions have been implicated in RNA binding: RNA recognition motifs (RRM) typically mediate sequence-specific RNA binding, whereas positively charged, unstructured regions provide binding sites for structured RNA, without sequence-specificity. Interaction partners modulate RNA binding to the core, or bind to RNA regions emanating from the core. The functional interplay of the helicase core and ancillary domains or interaction partners in RNA binding and unwinding is not entirely understood. This review summarizes our current knowledge on RNA binding to the DEAD-box helicase core and the roles of ancillary domains and interaction partners in RNA binding and unwinding by DEAD-box proteins.

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9

Juven-Gershon, T., J. Y. Hsu, and J. T. Kadonaga. "Perspectives on the RNA polymerase II core promoter." Biochemical Society Transactions 34, no. 6 (October 25, 2006): 1047–50. http://dx.doi.org/10.1042/bst0341047.

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The RNA polymerase II core promoter is a critical yet often overlooked component in the transcription process. The core promoter is defined as the stretch of DNA, which encompasses the RNA start site and is typically approx. 40–50 nt in length, that directs the initiation of gene transcription. In the past, it has been generally presumed that core promoters are general in function and that transcription initiation occurs via a common shared mechanism. Recent studies have revealed, however, that there is considerable diversity in core promoter structure and function. There are a number of DNA elements that contribute to core promoter activity, and the specific properties of a given core promoter are dictated by the presence or absence of these core promoter motifs. The known core promoter elements include the TATA box, Inr (initiator), BREu {BRE [TFIIB (transcription factor for RNA polymerase IIB) recognition element] upstream of the TATA box} and BREd (BRE downstream of the TATA box), MTE (motif ten element), DCE (downstream core element) and DPE (downstream core promoter element). In this paper, we will provide some perspectives on current and future issues that pertain to the RNA polymerase II core promoter.

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Jiang, Li, Zi Yu Wang, Xiu Wei Cheng, and Chao Yang Lu. "Experimental Study on Diesel Engine Intake Ports with Reverse Engineering Technology." Applied Mechanics and Materials 551 (May 2014): 315–19. http://dx.doi.org/10.4028/www.scientific.net/amm.551.315.

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Compared the principle and application effect of non-contact measuring data collecting method of intake ports: the nondestructive scanning method and laser scanning method. A intake port was developed for a four-valve diesel engine with reverse engineering technology, and different core boxes of intake port were made respectively by different measureing and manufacturing method, and were investigated in the steady-flow test with the original cylinder head of the diesel engine. The results show that the performance of the metal core box based on laser scanning is consistent with the original cylinder head. Compared with the epoxy resin core box based on nondestructive scanning method, the metal core box based on laser scanning can satisfy the requirement of development of intake port.

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11

Milgate, Michael. "Black-Box Protection of Core Competencies in Strategic Alliances." Journal of Management & Organization 6, no. 2 (March 2000): 32–43. http://dx.doi.org/10.1017/s183336720000540x.

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AbstractThis article presents a conceptual framework that participants in cooperative ventures may use to protect core competencies and proprietary information, while allowing the cooperative venture to benefit from these. While strategic alliances, in various forms, are becoming more common (Beamish and Delios, 1997), a potentially issue that often remains unresolved is how to protect your core competencies, while still cooperating openly with your partner, particularly when advanced technology is involved. It can be difficult for partners in an alliance to cooperate and openly share strategic know-how. Cooperation and openness are necessary, however, if a joint venture is to succeed. Since the success of any strategic alliance is based on cooperation, trust and an open sharing of competencies, potentially sensitive knowledge might be exposed through the joint venture. This is why many executives regard strategic alliances with reservation (Lorenz, 1992). They resist giving away core strategic competencies that might be misused in other contexts.

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12

Milgate, Michael. "Black-Box Protection of Core Competencies in Strategic Alliances." Journal of the Australian and New Zealand Academy of Management 6, no. 2 (March 2000): 32–43. http://dx.doi.org/10.5172/jmo.2000.6.2.32.

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AbstractThis article presents a conceptual framework that participants in cooperative ventures may use to protect core competencies and proprietary information, while allowing the cooperative venture to benefit from these. While strategic alliances, in various forms, are becoming more common (Beamish and Delios, 1997), a potentially issue that often remains unresolved is how to protect your core competencies, while still cooperating openly with your partner, particularly when advanced technology is involved. It can be difficult for partners in an alliance to cooperate and openly share strategic know-how. Cooperation and openness are necessary, however, if a joint venture is to succeed. Since the success of any strategic alliance is based on cooperation, trust and an open sharing of competencies, potentially sensitive knowledge might be exposed through the joint venture. This is why many executives regard strategic alliances with reservation (Lorenz, 1992). They resist giving away core strategic competencies that might be misused in other contexts.

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13

Bhuvaneswari, V., V. Amarnath, D. Balaji, H. Andrew Meshach, A. Aravinth, S. Dineshkumar, and V. S. Saravanan. "Productivity enhancement through coating of core box - A Review." IOP Conference Series: Materials Science and Engineering 1145, no. 1 (April 1, 2021): 012025. http://dx.doi.org/10.1088/1757-899x/1145/1/012025.

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14

Yu, Jing Liang. "The Construction Technique of Steel-Wood Composite Core Formwork in a Large Span Prestressed Hollow Box Guider." Advanced Materials Research 894 (February 2014): 18–21. http://dx.doi.org/10.4028/www.scientific.net/amr.894.18.

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Based on the comparison of several types of core formwork for large span hollow box girder, their structural characters, and assemble and disassemble in application is analysed to find that steel-wood core formwork is a better choice. Then the installation technique of steel-wood core formwork is discussed, including assemble, disassemble and anti-floating counter measures. The practice in some large span prestressed hollow box girder construction prove that steel-wood core formwork is a simple but effective core formwork construction technique with technological economic advantages because of its low cost, high working efficiency and better accuracy..

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15

Li, W. W., Y. Hsiung, V. Wong, K. Galvin, Y. Zhou, Y. Shi, and A. S. Lee. "Suppression of grp78 core promoter element-mediated stress induction by the dbpA and dbpB (YB-1) cold shock domain proteins." Molecular and Cellular Biology 17, no. 1 (January 1997): 61–68. http://dx.doi.org/10.1128/mcb.17.1.61.

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The highly conserved grp78 core promoter element plays an important role in the induction of grp78 under diverse stress signals. Previous studies have established a functional region in the 3' half of the core (stress-inducible change region [SICR]) which exhibits stress-inducible changes in stressed nuclei. The human transcription factor YY1 is shown to bind the SICR and transactivate the core element under stress conditions. Here we report that expression library screening with the core element has identified two new core binding proteins, YB-1 and dbpA. Both proteins belong to the Y-box family of proteins characterized by an evolutionarily conserved DNA binding motif, the cold shock domain (CSD). In contrast to YY1, which binds only double-stranded SICR, the Y-box/CSD proteins much prefer the lower strand of the SICR. The Y-box proteins can repress the inducibility of the grp78 core element mediated by treatment of cells with A23187, thapsigargin, and tunicamycin. In gel shift assays, YY1 binding to the core element is inhibited by either YB-1 or dbpA. A yeast interaction trap screen using LexA-YY1 as a bait and a HeLa cell cDNA-acid patch fusion library identified YB-1 as a YY1-interacting protein. In cotransfection experiments, the Y-box proteins antagonize the YY1-mediated enhancement of transcription directed by the grp78 core in stressed cells. Thus, the CSD proteins may be part of the stress signal transduction mechanism in the mammalian system.

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Veiga, Pedro, Ronnie Figueiredo, Sergio Teixeira, and Cristina Isabel I. Fernandes. "Opening Pandora's Box." Journal of Global Information Management 29, no. 1 (January 2021): 1–21. http://dx.doi.org/10.4018/jgim.2021010101.

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Global strategy research is rapidly increasing in quantity but is found in divergent literature and disciplines. Now is the time to offer a comprehensive review that identifies, synthesizes, and integrates previous research and highlights knowledge gaps and the way forward. This methodical literature search helped to identify 338 articles in the Web of Science database published until 2018. Using a systematic and in-depth content analysis using bibliometric techniques, the authors reviewed the articles and identified the main theories used and the methodological guidelines in these articles. This review helps to identify significant knowledge gaps in terms of theoretical orientation and core content. The main contributions of this paper are to outline and summarize a multilevel analysis of emerging global strategy literature, integrate and extract potential theoretical contributions in this field, and indicate directions for future research.

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RAM KUMAR, K., and N. GANESAN. "VIBRATION AND DAMPING STUDIES ON A HOLLOW SANDWICH BOX COLUMN WITH A VISCOELASTIC/ELECTRORHEOLOGICAL/MAGNETORHEOLOGICAL FLUID CORE LAYER BY THE FINITE ELEMENT METHOD." International Journal of Structural Stability and Dynamics 08, no. 04 (December 2008): 531–46. http://dx.doi.org/10.1142/s0219455408002831.

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In this paper, the vibration and damping of a hollow sandwich box column containing a viscoelastic layer (VEL) or an electrorheological (ER) or magnetorheological (MR) fluid core with a constraining layer are analyzed and a comparison of performance is made. The hollow sandwich box column comprises two skin plates and a VEL/ER/MR fluid core layer. The finite element method is used to study the vibration and damping behaviors of the column. The natural frequencies and modal loss factors are obtained by solving the complex eigenvalue problem. The modal dampings and natural frequencies of the column are calculated for various electric as well as magnetic fields and their performance is compared with that of the viscoelastic core layer for the clamped-free boundary condition. Effects of core thickness, electric voltage and magnetic field on the vibration behavior of the sandwich box column are investigated.

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18

Deng, W., and S. G. E. Roberts. "Core promoter elements recognized by transcription factor IIB." Biochemical Society Transactions 34, no. 6 (October 25, 2006): 1051–53. http://dx.doi.org/10.1042/bst0341051.

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The general transcription factor TFIIB (transcription factor IIB) plays a critical role in the assembly of the RNA polymerase II pre-initiation complex. TFIIB can make sequence-specific DNA contacts both upstream and downstream of the TATA box. This has led to the definition of two core promoter BREs (TFIIB-recognition elements), one upstream [BREu (upstream BRE)] and one downstream of TATA box [BREd (downstream BRE)]. TFIIB–BREu and TFIIB–BREd contacts are mediated by two independent DNA-recognition motifs within the core domain of TFIIB. Both the BREu and the BREd modulate the transcriptional potency of a promoter. However, the net effect of the BREs on promoter activity is dependent on the specific blend of elements present within a core promoter.

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Civáň, P., and M. Švec. "Genome-wide analysis of rice (Oryza sativa L. subsp. japonica) TATA box and Y Patch promoter elements." Genome 52, no. 3 (March 2009): 294–97. http://dx.doi.org/10.1139/g09-001.

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The TATA box is one of the best characterized transcription factor binding sites. However, it is not a ubiquitous element of core promoters, and other sequence motifs such as Y Patches seem to play a major role in plants. Here, we present a first genome-wide computational analysis of the TATA box and Y Patch distribution in rice ( Oryza sativa L. subsp. japonica) promoter sequences. Utilizing a probabilistic sequence model, we ascertain that only ~19% of rice genes possess the TATA box, but ~50% contain one or more Y Patches in their core promoters. By computational processing of identified elements, we generated extended TATA box and Y Patch nucleotide frequency matrices capable of predicting these motifs in plants with a high degree of confidence.

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Galan, Jean-Marc, Andreas Wiederkehr, Jae Hong Seol, Rosine Haguenauer-Tsapis, Raymond J. Deshaies, Howard Riezman, and Matthias Peter. "Skp1p and the F-Box Protein Rcy1p Form a Non-SCF Complex Involved in Recycling of the SNARE Snc1p in Yeast." Molecular and Cellular Biology 21, no. 9 (May 1, 2001): 3105–17. http://dx.doi.org/10.1128/mcb.21.9.3105-3117.2001.

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ABSTRACT Skp1p–cullin–F-box protein (SCF) complexes are ubiquitin-ligases composed of a core complex including Skp1p, Cdc53p, Hrt1p, the E2 enzyme Cdc34p, and one of multiple F-box proteins which are thought to provide substrate specificity to the complex. Here we show that the F-box protein Rcy1p is required for recycling of the v-SNARE Snc1p inSaccharomyces cerevisiae. Rcy1p localized to areas of polarized growth, and this polarized localization required its CAAX box and an intact actin cytoskeleton. Rcy1p interacted with Skp1p in vivo in an F-box-dependent manner, and both deletion of its F box and loss of Skp1p function impaired recycling. In contrast, cells deficient in Cdc53p, Hrt1p, or Cdc34p did not exhibit recycling defects. Unlike the case for F-box proteins that are known to participate in SCF complexes, degradation of Rcy1p required neither its F box nor functional 26S proteasomes or other SCF core subunits. Importantly, Skp1p was the only major partner that copurified with Rcy1p. Our results thus suggest that a complex composed of Rcy1p and Skp1p but not other SCF components may play a direct role in recycling of internalized proteins.

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Lai, Chao-Kuen, and Ling-Pai Ting. "Transcriptional Repression of Human Hepatitis B Virus Genes by a bZIP Family Member, E4BP4." Journal of Virology 73, no. 4 (April 1, 1999): 3197–209. http://dx.doi.org/10.1128/jvi.73.4.3197-3209.1999.

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ABSTRACT Box α is an essential element of both the upstream regulatory sequence of the core promoter and the second enhancer, which positively regulate the transcription of human hepatitis B virus (HBV) genes. In this paper, we describe the cloning and characterization of a box α binding protein, E4BP4. E4BP4 is a bZIP type of transcription factor. Overexpression of E4BP4 represses the stimulating activity of box α in the upstream regulatory sequence of the core promoter and the second enhancer in differentiated human hepatoma cell lines. E4BP4 can also suppress the transcription of HBV genes and the production of HBV virions in a transient-transfection system that mimics the viral infection in vivo. Expression of an E4BP4 antisense transcript can, instead, elevate the transcription of the core promoter. A low abundance of E4BP4 protein and mRNA in differentiated human hepatoma cell lines is detected, and E4BP4 is not a major component of box α binding proteins in untransfected differentiated human hepatoma cell lines. C/EBPα and C/EBPβ, in contrast, are major components of the box α binding activity present in nuclear extracts. E4BP4 has a stronger binding affinity towards box α than the endogenous box α binding activity present in nuclear extracts. Structure and function analysis of E4BP4 reveals that DNA binding activity is sufficient to confer the negative regulatory function of E4BP4. These results indicate that binding site occlusion is the mechanism whereby E4BP4 suppresses transcription in HBV.

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ZANG, Qing-lai, Xing ZHANG, and Guo-xun WU. "Restrained Torsion of Thin-walled Box Beam with Honeycomb Core." Chinese Journal of Aeronautics 18, no. 4 (November 2005): 336–45. http://dx.doi.org/10.1016/s1000-9361(11)60253-7.

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ZANG, Qing-lai, Xing ZHANG, and Guo-xun WU. "Restrained Bending of Thin-Walled Box Beam with Honeycomb Core." Chinese Journal of Aeronautics 18, no. 3 (August 2005): 223–29. http://dx.doi.org/10.1016/s1000-9361(11)60302-6.

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Burke, S. K., W. H. Berger, W. T. Coulbourn, and E. Vincent. "Benthic foraminifera in box core ERDC 112, Ontong Java Plateau." Journal of Foraminiferal Research 23, no. 1 (January 1, 1993): 19–39. http://dx.doi.org/10.2113/gsjfr.23.1.19.

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Carballo-Rubio, Raúl, Francesco Di Filippo, Stefano Liberati, and Matt Visser. "Opening the Pandora’s box at the core of black holes." Classical and Quantum Gravity 37, no. 14 (June 25, 2020): 145005. http://dx.doi.org/10.1088/1361-6382/ab8141.

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Stachowicz, M., K. Granat, and P. Obuchowski. "Evaluation of the Possibilities of Sodium Silicate Sands Application in Automated Hot-Box Process of Cores Shooting." Archives of Foundry Engineering 17, no. 4 (December 20, 2017): 155–60. http://dx.doi.org/10.1515/afe-2017-0149.

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AbstractThe paper presents the results of preliminary research on the use of silica sands with hydrated sodium silicate 1.5% wt. of binder for the performance of eco-friendly casting cores in hot-box technology. To evaluate the feasibility of high quality casting cores performed by the use of this method, the tests were made with the use of a semiautomatic core shooter using the following operating parameters: initial shooting pressure of 6 bar, shot time 4 s and 2 s, core-box temperature 200, 250 and 300 °C and core heating time 30, 60, 90 and 150 s. Matrixes of the moulding sands were two types of high-silica sand: fine and medium. Moulding sand binder was a commercial, unmodified hydrated sodium silicate having a molar module SiO2/ Na2O of 2.5. In one shot of a core-shooter were made three longitudinal samples (cores) with a total volume of about 2.8 dm3. The samples thus obtained were subjected to an assessment of the effect of shooting parameters, i.e. shooting time, temperature and heating time, using the criteria: core-box fill rate, bending strength (RgU), apparent density and surface quality after hardening. The results of the trials on the use of sodium silicate moluding sands made it possible to further refine the conditions of next research into the improvement of inorganic warm-box / hot-box technology aimed at: reduction of heating temperature and shot time. It was found that the performance of the cores depends on the efficiency of the venting system, shooting time, filling level of a shooting chamber and grains of the silica matrix used.

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SUSLOV, VALENTIN V., PETR M. PONOMARENKO, VADIM M. EFIMOV, LUDMILA K. SAVINKOVA, MIKHAIL P. PONOMARENKO, and NIKOLAY A. KOLCHANOV. "SNPS IN THE HIV-1 TATA BOX AND THE AIDS PANDEMIC." Journal of Bioinformatics and Computational Biology 08, no. 03 (June 2010): 607–25. http://dx.doi.org/10.1142/s0219720010004677.

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Evolutionary trends have been examined in 146 HIV-1 forms (2662 copies, 2311 isolates) polymorphic for the TATA box using the "DNA sequence→affinity for TBP" regression (TBP is the TATA binding protein). As a result, a statistically significant excess of low-affinity TATA box HIV-1 variants corresponding to a low level of both basal and TAT-dependent expression and, consequently, slow replication of HIV-1 have been detected. A detailed analysis revealed that the excess of slowly replicating HIV-1 is associated with the subtype E-associated TATA box core sequence "CATAAAA". Principal Component Analysis performed on 2662 HIV-1 TATA box copies in 70 countries revealed the presence of two principal components, PC1 (75.7% of the variance) and PC2 (23.3% of the variance). They indicate that each of these countries is specifically associated with one of the following trends in HIV-1 evolution: neutral drift around the normal TATA box; neutral drift around the slowly replicating TATA box core sequence (phylogenetic inertia); an adaptive increase in the frequency of the slowly replicating form.

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McKeegan, Kenneth Scott, Charles Maurice Debieux, and Nicholas James Watkins. "Evidence that the AAA+ Proteins TIP48 and TIP49 Bridge Interactions between 15.5K and the Related NOP56 and NOP58 Proteins during Box C/D snoRNP Biogenesis." Molecular and Cellular Biology 29, no. 18 (July 20, 2009): 4971–81. http://dx.doi.org/10.1128/mcb.00752-09.

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ABSTRACT The box C/D small nucleolar RNPs (snoRNPs) are essential for the processing and modification of rRNA. TIP48 and TIP49 are two related AAA+ proteins that are essential for the formation of box C/D snoRNPs. These proteins are key components of the pre-snoRNP complexes, but their exact role in box C/D snoRNP biogenesis is largely uncharacterized. Here we report that TIP48 and TIP49 interact with one another in vitro, and only the TIP48/TIP49 complex, but not the individual proteins, possesses significant ATPase activity. Loss of TIP48 and TIP49 results in a change in pre-snoRNA levels and a loss of U3 snoRNA signal in the Cajal body. We show that TIP48 and TIP49 make multiple interactions with core snoRNP proteins and biogenesis factors and that these interactions are often regulated by the presence of ATP. Furthermore, we demonstrate that TIP48 and TIP49 efficiently bridge interactions between the core box C/D proteins NOP56 or NOP58 and 15.5K. Our data imply that the snoRNP assembly factor NUFIP can regulate the interactions between TIP48 and TIP49 and the core box C/D proteins. We suggest that snoRNP assembly involves an intricate series of interactions that are mediated/regulated by bridging factors and chaperones.

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Ouyang, Zhiming, Jianli Zhou, Chad A. Brautigam, Ranjit Deka, and Michael V. Norgard. "Identification of a core sequence for the binding of BosR to the rpoS promoter region in Borrelia burgdorferi." Microbiology 160, no. 5 (May 1, 2014): 851–62. http://dx.doi.org/10.1099/mic.0.075655-0.

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The alternative sigma factor RpoS in Borrelia burgdorferi plays a central role in modulating host adaptive responses when spirochaetes cycle between ticks and mammals. The transcriptional activation of σ54-dependent rpoS requires a Fur homologue designated BosR. Previously, BosR was shown to directly activate rpoS transcription by binding to the rpoS promoter. However, many other DNA binding features of BosR have remained obscure. In particular, the precise DNA sequence targeted by BosR has not yet been completely elucidated. The prediction of a putative Per box within the rpoS promoter region has further confounded the identification of the BosR binding sequence. Herein, by using electrophoretic mobility shift assays, we demonstrate that the putative Per box predicted in the rpoS promoter region is not involved in the binding of BosR. Rather, a 13 bp palindromic sequence (ATTTAANTTAAAT) with dyad symmetry, which we denote as the ‘BosR box’, functions as the core sequence recognized by BosR in the rpoS promoter region of Borrelia burgdorferi. Similar to a Fur box and a Per box, the BosR box probably comprises a 6–1–6 inverted repeat composed of two hexamers (ATTTAA) in a head-to-tail orientation. Selected mutations in the BosR box prevented recombinant BosR from binding to rpoS. In addition, we found that sequences neighbouring the BosR box also are required for the formation of BosR–DNA complexes. Identification of the BosR box advances our understanding of how BosR recognizes its DNA target(s), and provides new insight into the mechanistic details behind the unique regulatory function of BosR.

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Dobosz, St M., A. Grabarczyk, K. Major-Gabryś, and D. Bolibruchova. "Elasticity of cores manufactured in cold box technology." Archives of Metallurgy and Materials 62, no. 1 (March 1, 2017): 351–54. http://dx.doi.org/10.1515/amm-2017-0053.

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Abstract In the foundry industry, as in many other fields we seek to achieve the best quality with the least losses and the lowest cost. To meet these demands numerous plants increased automatization of their manufacturing processes. However, with changes in the production process it is necessary to change also the materials used. Not only casting alloys that are used in production, but also applied moulding and core sands are important. Proper selection and evaluation of the properties of used moulding mixtures is crucial in order to achieve a highly efficient production. In this article a new issue concerning the use of flexibility in foundry molding and core was mentioned. It explains the principles of measurement and interpretation of the obtained results for the cold-box moulding sands.

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Fyfe, Janet A. M., and John K. Davies. "An AT-Rich Tract Containing an Integration Host Factor-Binding Domain and Two UP-Like Elements Enhances Transcription from thepilEp1 Promoter of Neisseria gonorrhoeae." Journal of Bacteriology 180, no. 8 (April 15, 1998): 2152–59. http://dx.doi.org/10.1128/jb.180.8.2152-2159.1998.

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ABSTRACT The pilE gene of Neisseria gonorrhoeae is transcribed from a ς70 promoter (pilEp 1) with an AT-rich tract extending 65 nucleotides upstream of the −35 box. Within this region is an integration host factor (IHF)-binding core consensus sequence. We have performed a detailed analysis to determine which upstream sequences are required for efficient transcription frompilEp 1 in N. gonorrhoeae. Deletion of sequences upstream of the AT-rich tract had no effect on the level of transcription. However, the IHF-binding core consensus sequence and the AT-rich sequence further upstream were both required for enhanced levels of transcription from this promoter in both N. gonorrhoeae and an Escherichia coli strain producing IHF. In addition, an UP-like element positioned between the −35 box and the IHF-binding site was required for maximal transcription. The AT-rich region upstream of the IHF-binding core consensus sequence can also act as an UP-like element when appropriately repositioned upstream of the −35 box.

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Barabba, Vincent. "Assessing General Motors’ innovation strategy over three decades using the “Three Box Solution”." Strategy & Leadership 47, no. 2 (March 18, 2019): 34–42. http://dx.doi.org/10.1108/sl-01-2019-0004.

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Purpose Professor Vijay Govindarajan’s “Three Box Solution” framework provides a useful way of looking at a transformative business innovation initiative started at General Motors almost three decades ago and now being further developed by its current CEO Mary Barra. Design/methodology/approach Drawing on 18 years of experience at GM the author offers insights into how the company used the “Three Box” aproach: 10;•9;Box 1: Strengthen the core. 10;•9;Box 2: Let go of the practices that drive the core business but hinder the new one. 10;•9;Box 3: Invented a new business model. 10; Findings GM management found creative ways to enable the current business to thrive while exploring the potential market for a visionary business model. Practical implications %2010%3BThe%20paper%20provides%20new%20insight%20into%20how%20General%20Motors%20has%20changed%20and%20how%20it%20is%20continuing%20to%20adapt%20%20emerging%20future%20markets.. Originality/value Based on actual experience of participating in strategy development this paper should help decision makers address their current actions and future strategies simultaneously.

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ten Hove, J. B., J. Wang, F. W. B. van Leeuwen, and A. H. Velders. "Dendrimer-encapsulated nanoparticle-core micelles as a modular strategy for particle-in-a-box-in-a-box nanostructures." Nanoscale 9, no. 47 (2017): 18619–23. http://dx.doi.org/10.1039/c7nr06773a.

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Šimas, L., and G. Tzifa. "F. Hoffmann-La Roche v AGCM: Misleading Information Fits Into the ‘Object Box’." European Competition and Regulatory Law Review 2, no. 2 (2018): 138–42. http://dx.doi.org/10.21552/core/2018/2/10.

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Mikóné Mádi, Laura, László Varga, and Tamás Mikó. "Examination of the Properties of Resin Bonded Core Mixtures." Materials Science Forum 885 (February 2017): 171–77. http://dx.doi.org/10.4028/www.scientific.net/msf.885.171.

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The production technology for automotive foundry castings has developed significantly during the past decade. The production of cylinder hats with more and more complex designs could be rather challenging for core makers. Heating might cause the annealing of the core, thus, the buoyancy of the molten metal increases which might cause the movement of the core. The heat distortion of the cores was examined with a Hot Distortion Tester. A universal Instron 5982 device was used for bending, wedge penetration strength and cold and hot compression tests. The test bars were prepared with cold- and hot-box processes using DMPA (Dimethylpropyl-amine) under laboratory conditions. The tests showed that the decrease of the bending strength is proportional to the amount of additives. The compression test results showed that the test bars produced with cold-box compression have the lowest and the ones with furan resin mixtures have the highest compressive strength.

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Aittaleb, Mohamed, Rumana Rashid, Qiong Chen, John R. Palmer, Charles J. Daniels, and Hong Li. "Structure and function of archaeal box C/D sRNP core proteins." Nature Structural & Molecular Biology 10, no. 4 (February 24, 2003): 256–63. http://dx.doi.org/10.1038/nsb905.

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Fonseca, Erik R., and Carlos I. Mendoza. "Self-assembly of core-corona particles confined in a circular box." Journal of Physics: Condensed Matter 32, no. 1 (October 11, 2019): 015101. http://dx.doi.org/10.1088/1361-648x/ab42fc.

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Mingjuan, CUI. "Prediction on Deflection of Box-Core Sandwich Panels in Weak Direction." Open Ocean Engineering Journal 6, no. 1 (December 30, 2013): 42–58. http://dx.doi.org/10.2174/1874835x01306010042.

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Rodríguez, Eduardo, Alberto Pérez, Rafael David Mercado-Solis, Velasco-Téllez Abraham, Omar Jiménez, Martín Flores, Marco Aurelio González, and Jesús Ibarra. "Erosion problem in tool steel using cold box core-making process." China Foundry 16, no. 3 (May 2019): 204–10. http://dx.doi.org/10.1007/s41230-019-8156-0.

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Järvinen, Pekka, and Kerstin Engström. "Biological monitoring of triethylamine among cold-box core makers in foundries." International Archives of Occupational and Environmental Health 70, no. 6 (November 20, 1997): 424–27. http://dx.doi.org/10.1007/s004200050240.

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Boyd, K. E., and P. J. Farnham. "Myc versus USF: discrimination at the cad gene is determined by core promoter elements." Molecular and Cellular Biology 17, no. 5 (May 1997): 2529–37. http://dx.doi.org/10.1128/mcb.17.5.2529.

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Carbamoyl-phosphate synthase/aspartate carbamoyltransferase/dihydroorotase, which is encoded by the cad gene, is required for the first three rate-limiting steps of de novo pyrimidine biosynthesis. It has been previously demonstrated that cad transcription increases at the G1/S-phase boundary, as quiescent cells reenter the proliferative cell cycle. The growth-responsive element has been mapped to an E box at +65 in the hamster cad promoter. Using an in vivo UV cross-linking and immunoprecipitation assay, we show that Myc, Max, and upstream stimulatory factor (USF) bind to the chromosomal cad promoter. To determine whether binding of Myc-Max or USF is critical for cad growth regulation, we analyzed promoter constructs which contain mutations in the nucleotides flanking the E box. We demonstrate that altering nucleotides which flank the cad E box to sequences which decrease Myc-Max binding in vitro correlates with a loss of cad G1/S-phase transcriptional activation. This result supports the conclusion that binding of Myc-Max, but not USF, is essential for cad regulation. Our investigations demonstrate that the endogenous cad E box can be bound by more than one transcription factor, but growth-induced cad expression is achieved only by Myc.

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Persinger, Jim, Sarojini M. Sengupta, and Blaine Bartholomew. "Spatial Organization of the Core Region of Yeast TFIIIB-DNA Complexes." Molecular and Cellular Biology 19, no. 7 (July 1, 1999): 5218–34. http://dx.doi.org/10.1128/mcb.19.7.5218.

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ABSTRACT The interaction of yeast TFIIIB with the region upstream of theSUP4 tRNATyr gene was extensively probed by use of photoreactive phosphodiesters, deoxyuridines, and deoxycytidines that are site specifically incorporated into DNA. The TATA binding protein (TBP) was found to be in close proximity to the minor groove of a TATA-like DNA sequence that starts 30 nucleotides upstream of the start site of transcription. TBP was cross-linked to the phosphate backbone of DNA from bp −30 to −20 in the nontranscribed strand and from bp −28 to −24 in the transcribed strand (+1 denotes the start site of transcription). Most of the major groove of DNA in this region was shown not to be in close proximity to TBP, thus resembling the binding of TBP to the TATA box, with one notable exception. TBP was shown to interact with the major groove of DNA primarily at bp −23 and to a lesser degree at bp −25 in the transcribed strand. The stable interaction of TBP with the major groove at bp −23 was shown to require the B" subunit of TFIIIB. The S4 helix and flanking region of TBP were shown to be proximal to the major groove of DNA by peptide mapping of the region of TBP cross-linked at bp −23. Thus, TBP in the TFIIIB-SUP4 gene promoter region is bound in the same direction as TBP bound to the TATA box with respect to the transcription start site. The B" and TFIIB-related factor (BRF) subunits of TFIIIB are positioned on opposite sides of the TBP-DNA core of the TFIIIB complex, as indicated by correlation of cross-linking data to the crystal structure of the TBP-TATA box complex. Evidence is given for BRF binding near the C-terminal stirrup of TBP, similar to that of TFIIB near the TBP-TATA box complex. The protein clamp formed around the TBP-DNA complex by BRF and B" would help explain the long half-life of the TFIIIB-DNA complex and its resistance to polyanions and high salt. The path of DNA traversing the surface of TBP at the 3′ end of the TATA-like element in the SUP4 tRNA gene is not the same as that of TBP bound to a TATA box element, as shown by the cross-linking of TBP at bp −23.

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Kern, M. J., and J. G. Woodward. "The same CCAAT box-binding factor binds to the promoter of two coordinately regulated major histocompatibility complex class II genes." Molecular and Cellular Biology 11, no. 1 (January 1991): 578–81. http://dx.doi.org/10.1128/mcb.11.1.578.

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Using competition mobility shift, methylation interference, and proteolytic clipping DNA binding assays, we demonstrate that the protein binding the major histocompatibility complex A beta CCAAT box is indistinguishable from the protein previously named NF-Y, which binds the major histocompatibility complex E alpha CCAAT box. Although the two CCAAT boxes share the same 10-base core sequence, termed the Y box, their flanking sequences, known to be important for binding, are very different.

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Kern, M. J., and J. G. Woodward. "The same CCAAT box-binding factor binds to the promoter of two coordinately regulated major histocompatibility complex class II genes." Molecular and Cellular Biology 11, no. 1 (January 1991): 578–81. http://dx.doi.org/10.1128/mcb.11.1.578-581.1991.

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Using competition mobility shift, methylation interference, and proteolytic clipping DNA binding assays, we demonstrate that the protein binding the major histocompatibility complex A beta CCAAT box is indistinguishable from the protein previously named NF-Y, which binds the major histocompatibility complex E alpha CCAAT box. Although the two CCAAT boxes share the same 10-base core sequence, termed the Y box, their flanking sequences, known to be important for binding, are very different.

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Wang, ChunYan, SongChun Zou, and WanZhong Zhao. "Multi-objective optimization of a novel crash box with a three-dimensional negative Poisson’s ratio inner core." Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering 233, no. 2 (November 29, 2017): 263–75. http://dx.doi.org/10.1177/0954407017741780.

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The crash box can absorb energy from the beam as much as possible, so as to reduce the collision damage to the front part of the car body and protect the safety of passengers. This work proposes a novel crash box filled with a three-dimensional negative Poisson’s ratio (NPR) inner core based on an inner hexagonal cellular structure. In order to optimize and improve the crash box’s energy absorption performance, the multi-objective optimization model of the NPR crash box is established, which combines the optimal Latin hypercube design method and response surface methodology. Then, the microstructure parameters are further optimized by the multi-objective particle swarm optimization algorithm to obtain an excellent energy absorption effect. The simulation results show that the proposed NPR crash box can generate smooth and controllable deformation to absorb the total energy, and it can further enhance the crashworthiness through the designed optimization algorithm.

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Feng, Xiaofan, and Mario Andrea Marchisio. "Novel S. cerevisiae Hybrid Synthetic Promoters Based on Foreign Core Promoter Sequences." International Journal of Molecular Sciences 22, no. 11 (May 27, 2021): 5704. http://dx.doi.org/10.3390/ijms22115704.

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Promoters are fundamental components of synthetic gene circuits. They are DNA segments where transcription initiation takes place. New constitutive and regulated promoters are constantly engineered in order to meet the requirements for protein and RNA expression into different genetic networks. In this work, we constructed and optimized new synthetic constitutive promoters for the yeast Saccharomyces cerevisiae. We started from foreign (e.g., viral) core promoters as templates. They are, usually, unfunctional in yeast but can be activated by extending them with a short sequence, from the CYC1 promoter, containing various transcription start sites (TSSs). Transcription was modulated by mutating the TATA box composition and varying its distance from the TSS. We found that gene expression is maximized when the TATA box has the form TATAAAA or TATATAA and lies between 30 and 70 nucleotides upstream of the TSS. Core promoters were turned into stronger promoters via the addition of a short UAS. In particular, the 40 nt bipartite UAS from the GPD promoter can enhance protein synthesis considerably when placed 150 nt upstream of the TATA box. Overall, we extended the pool of S. cerevisiae promoters with 59 new samples, the strongest overcoming the native TEF2 promoter.

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Kjær, Helle Astrid, Lisa Lolk Hauge, Marius Simonsen, Zurine Yoldi, Iben Koldtoft, Maria Hörhold, Johannes Freitag, Sepp Kipfstuhl, Anders Svensson, and Paul Vallelonga. "A portable lightweight in situ analysis (LISA) box for ice and snow analysis." Cryosphere 15, no. 8 (August 11, 2021): 3719–30. http://dx.doi.org/10.5194/tc-15-3719-2021.

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Abstract. There are enormous costs involved in transporting snow and ice samples to home laboratories for “simple” analyses in order to constrain annual layer thicknesses and identify accumulation rates of specific sites. It is well known that depositional noise, incurred from factors such as wind drifts, seasonally biased deposition and melt layers can influence individual snow and firn records and that multiple cores are required to produce statistically robust time series. Thus, at many sites, core samples are measured in the field for densification, but the annual accumulation and the content of chemical impurities are often represented by just one core to reduce transport costs. We have developed a portable “lightweight in situ analysis” (LISA) box for ice, firn and snow analysis that is capable of constraining annual layers through the continuous flow analysis of meltwater conductivity and hydrogen peroxide under field conditions. The box can run using a small gasoline generator and weighs less than 50 kg. The LISA box was tested under field conditions at the East Greenland Ice-core Project (EastGRIP) deep ice core drilling site in northern Greenland. Analysis of the top 2 m of snow from seven sites in northern Greenland allowed the reconstruction of regional snow accumulation patterns for the 2015–2018 period (summer to summer).

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Kajiwara, Moto, Tomohiro Terada, Jun-ichi Asaka, Masayo Aoki, Toshiya Katsura, Iwao Ikai, and Ken-ichi Inui. "Regulation of basal core promoter activity of human organic cation transporter 1 (OCT1/SLC22A1)." American Journal of Physiology-Gastrointestinal and Liver Physiology 295, no. 6 (December 2008): G1211—G1216. http://dx.doi.org/10.1152/ajpgi.90360.2008.

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Human organic cation transporter 1 (OCT1/SLC22A1) plays important roles in the hepatic uptake of cationic drugs. The functional characteristics of this transporter have been well evaluated, but molecular information regarding transcriptional regulation is limited. In the present study, therefore, we examined the gene regulation of OCT1 gene focusing on basal core expression. An ∼2.5-kb fragment of the OCT1 promoter region was isolated, and promoter activity was measured by luciferase assay in the human liver cell lines Huh7 and HepG2. Deletion analysis suggested that the region spanning −141/−69 was essential for the basal core transcriptional activity and that this region contained the sequence of a cognate E-box (CACGTG). The E-box is known to be bound by the basal transcription factors, upstream stimulating factors (USFs), and the functional involvements of USF1 and USF2 were confirmed by a transactivation effect, a mutational analysis of the E-box, and an electrophoretic mobility shift assay. The transactivation effect of USFs on the OCT1 promoter was further stimulated by hepatocyte nuclear factor 4α, a liver-enriched transcription factor. There were no polymorphisms in the proximal promoter region (about 400 bp) of OCT1 gene ( n = 109). These findings indicated that both USF1 and USF2 bind to an E-box sequence located in the OCT1 core promoter region and are required for the basal gene expression of this transporter.

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Conlon, Frank L., Lynne Fairclough, Brenda M. J. Price, Elena S. Casey, and J. C. Smith. "Determinants of T box protein specificity." Development 128, no. 19 (October 1, 2001): 3749–58. http://dx.doi.org/10.1242/dev.128.19.3749.

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Members of the T box family of transcription factors play important roles in early development. Different members of the family exert different effects and here we show that much of the specificity of the Xenopus T box proteins Xbra, VegT and Eomesodermin resides in the DNA-binding domain, or T box. Binding site selection experiments show that the three proteins bind the same core sequence, but they select paired sites that differ in their orientation and spacing. Lysine 149 of Xbra is conserved in all Brachyury homologues, while the corresponding amino acid in VegT and Eomesodermin is asparagine. Mutation of this amino acid to lysine changes the inductive abilities of VegT and Eomesodermin to resemble that of Xbra.

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GERRING, JOHN. "The Mechanismic Worldview: Thinking Inside the Box." British Journal of Political Science 38, no. 1 (December 7, 2007): 161–79. http://dx.doi.org/10.1017/s0007123408000082.

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A widespread turn towards mechanism-centred explanations can be viewed across the social sciences in recent decades. This article clarifies what it might mean in practical terms to adopt a mechanismic view of causation. This simple task of definition turns out to be considerably more difficult than it might at first appear. The body of the article elucidates a series of tensions and conflicts within this ambient concept, looking closely at how influential authors have employed this ubiquitous term. It is discovered that ‘mechanism’ has at least nine distinct meanings as the term is used within contemporary social science: (1) the pathway or process by which an effect is produced; (2) an unobservable causal factor; (3) an easy-to-observe causal factor; (4) a context-dependent (bounded) explanation; (5) a universal (or at least highly general) explanation; (6) an explanation that presumes highly contingent phenomena; (7) an explanation built on phenomena that exhibit lawlike regularities; (8) a distinct technique of analysis (based on qualitative, case study, or process-tracing evidence); or (9) a micro-level explanation for a causal phenomenon. Some of these meanings may be combined into coherent definitions; others are obviously contradictory. It is argued, however, that only the first meaning is consistent with all contemporary usages and with contemporary practices within the social sciences; this is therefore proposed as a minimal (core) definition of the concept. The other meanings are regarded as arguments surrounding the core concept.

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Journal articles on the topic 'Core box'

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