Unfolding Phenomenon Research Articles

Attitudes to fake news verification: Youth orientations to ‘right click’ authenticate

This article examines the phenomenon of fake news through a survey of university students in the United Kingdom. The survey, composed through a selection of factual and non-factual content/news and complemented through a validation tool, sought to assess the attitudes of these respondents to items of factual misinformation before and after these were verified with the tool. The findings from the survey present online misinformation as a very complex and unfolding phenomenon in terms of user behaviour, particularly when presented with an authentication tool. The majority of respondents failed in identifying factual from fake news posts. While respondents indicated mistrust in using third-party validation tools, the majority indicated a critical need for a verification tool that would support their quest and increase their trust in what they read online.

Digital Platforms in Contemporary India: The Transformation of Quotidian Life Worlds

Abstract The introduction to the special issue on ‘Digital Platforms in Contemporary India: Transformation of Quotidian Life Worlds’ focuses on the ways in which everyday interactions in contemporary India have changed since the arrival of digital platforms. Locating these changes within their specific contexts, the essays in the special issue examine the new circulatory assemblages and representational tropes that emerge through interactions between diverse platforms and their various users. In particular, the essays trace the different ways in which bodies, mobilities, and platforms are entangled in everyday life in an unfolding phenomenon. This introduction outlines the new spatiotemporal shifts catalyzed by the platformization of everyday activities in India, drawing connections among the various essays in the special issue. The introduction attempts to map these shifts as part of a two-way process, which acknowledges that the resulting transformations also have the potential for reimagining the existing logic of platforms.

Elasto‐Capillary Manipulation of Freestanding Inorganic Nanosheets: An Implication for Nano‐Manufacturing of Low‐Dimensional Structures

AbstractUltrathin inorganic nanosheets (e.g., 2D nanomaterials, thin films, etc.) have attracted tremendous research interest because of their unique properties and promising applications. However, because of their ultrathin thickness (<100 nm) and low flexural rigidity, it is difficult to manufacture low‐dimensional structures using these nanosheets. In this work, the observation of an intriguing elasto‐capillary unfolding phenomenon is first reported which occurs on a variety of freestanding inorganic nanosheets floating on a liquid surface. Through theoretical modeling and experiments, it is demonstrated that one can easily unfold, re‐roll, and transport different kinds of nanosheets by tuning the interfacial properties of the liquid. As a result, one can assemble nanosheets on the liquid surface into small structures (e.g., heterogeneous scrolls, optical resonators) and/or transfer them out of the liquid surface onto other surfaces for the manufacturing of flexible devices. The outcome of this research paves the way for nano‐manufacturing of low‐dimensional structures with ultrathin inorganic nanosheets.

Refolding of denatured gold nanoparticles-conjugated bovine serum albumin through formation of catanions between gemini surfactant and sodium dodecyl sulphate.

The present work elucidates binding interactions of sodium dodecyl sulphate (SDS) with the conjugated gold nanoparticles (AuNPs)-bovine serum albumin (BSA), unfolded by each of two gemini surfactants, 1,4-bis(dodecyl-N,N-dimethylammonium bromide)-butane (12-4-12,2Br−) or 1,8-bis(dodecyl-N,N-dimethylammonium bromide)-octane (12-8-12,2Br−). Initially, at a low concentration of SDS there is a relaxation of bioconjugates from their compressed form due to the formation of catanions between SDS and gemini surfactants. On moving towards higher concentrations of SDS, these relaxed unfolded bioconjugates renature by removal of residual bound gemini surfactants. Mixed assemblies of SDS and gemini surfactants formed during refolding of bioconjugates are characterized by DLS and FESEM measurements. A step-by-step process of refolding observed for these denatured protein bioconjugates is exactly the inverse of their unfolding phenomenon. Parameters concerning nanometal surface energy transfer (NSET) and Förster's resonance energy transfer (FRET) phenomenon were employed to develop a binding isotherm. Moreover, there remains an inverse relationship between α-helix and β-turns of bioconjugates during the refolding process. Significantly, in the presence of 12-8-12,2Br−, SDS induces more refolding as compared to that for 12-4-12,2Br−. Bioconjugation shows an effect on the secondary structures of refolded BSA, which has been explored in detail through various studies such as Fourier transform infrared spectroscopy, fluorescence, and circular dichroism (CD). Therefore, this approach vividly describes the refolding of denatured bioconjugates, exploring structural information regarding various catanions formed during the process that would help in understanding distance-dependent optical biomolecular detection methodologies and physicochemical properties.

Studying Calcium Ion-Dependent Effect on the Inter-subunit Interaction Between the cTnC N-terminal Domain and cTnI C-terminal Switch Peptide of Human Cardiac Troponin via Chou’s 5-Steps Rule

Human cardiac troponin (cTn) is a calcium ion (Ca2+)-sensitive hetero-trimer complex that consists of three subunits: cTnC, cTnI and cTnT. The protein is a primary biomarker and potential target for the diagnosis and therapy of myocardial necrosis in acute coronary syndrome. Previously, a minimal region (mSwt peptide) of cTnI C-terminal switch peptide is identified as a functionally required segment for mediating cTnI interaction with the cTnC N-terminal domain to which Ca2+ binds. Here, we attempt to investigate the Ca2+-dependent effect on the inter-subunit interaction between cTnC and cTnI at molecular level. The structure of Ca2+-bound and Ca2+-free cTnC N-terminal domains as well as their complexes with mSwt peptide are stripped from the crystal structure of full-length cTn complex, which are then subjected to 600-ns molecular dynamics simulations for conformational equilibrium and post energetics analysis. It is revealed that Ca2+ can effectively stabilize the native conformation of cTnC N-terminal domain and the tight binding mode of mSwt peptide to the domain; lack of Ca2+ would cause a considerable unfolding phenomenon in the domain, particularly in helices H1 and H5, and largely shift the interaction manner between the domain and peptide. In addition, there is also a significant difference between the binding curves of mSwt peptide to Ca2+-bound and Ca2+-free domains along the dynamics trajectory; the former monotonically increases over the whole simulations, whereas the latter exhibits a unimodal profile. Binding analysis also observes a significant concentration-dependent effect of Ca2+ on the domain–peptide affinity, that is, just a little of Ca2+ can improve the affinity remarkably. Overall, it is demonstrated that Ca2+ plays a crucial role in domain–peptide interaction and Ca2+ should bind very efficiently to the domain.

Molecular-Level Profiling of Human Serum Transferrin Protein through Assessment of Nanopore-Based Electrical and Chemical Responsiveness.

In this study, we investigated the voltage and pH responsiveness of human serum transferrin (hSTf) protein using silicon nitride (Si xN y) nanopores. The Fe(III)-rich holo form of hSTf was dominant when pH > pI, while the Fe(III)-free apo form was dominant when pH < pI. The translocations of hSTf were purely in an electrophoretic sense, thus depended on its pI and the solution pH. With increasing voltage, voltage driven protein unfolding became prominent which was indicated by the trends associated with change in conductance, due to hSTf translocation, and in the excluded electrolyte volume. Additionally, analysis of the translocation events of the pure apo form of hSTf showed a clear difference in the event population compared to that of the holo form. The results obtained demonstrate the successful application of nanopore devices to distinguish between the holo and apo forms of hSTf in a mixture and to analyze its folding and unfolding phenomenon over a range of pH and applied voltages.

Can 2,2,2-trifluoroethanol be an efficient protein denaturant than methanol and ethanol under thermal stress?

Monohydric alcohols, such as methanol (MEH), ethanol (ETH) and 2,2,2-trifluoroethanol (TFE), have significant effects on biological processes including the protein folding-unfolding phenomenon. Among the several monohydric alcohols, TFE, a fluorine-substituted alcohol, is known to induce a helical structure in proteins. In this work, we report the heterogeneous unfolding phenomenon of a small protein Chymotrypsin Inhibitor 2 in various concentrations of methanol, ethanol and TFE solutions by performing atomistic molecular dynamics simulation studies. Our study reveals that the unfolding phenomenon of CI2 under thermal stress majorly depends on the concentration and the nature of the alcohol. The presence of alcohols in general has been noted to accelerate the unfolding process compared to pure water and TFE, among them all, has been found to speed up the unfolding time scale at low concentrations. The molecular contact frequency between protein and alcohol follows the trend, MEH < ETH < TFE at low concentrations, whereas the trend becomes MEH ∼ ETH > TFE at more concentrated solutions. The differential water-mediated and self-clustering phenomena of alcohols, diverse protein-alcohol hydrogen bond strengths and the concentration dependent restricted inhomogeneous protein-water as well as protein-alcohol hydrogen bond dynamics suggest that TFE, a well known α-helix stabilizer, could be a good competitor among its class of denaturants.

INTEGRASI NILAI-NILAI ANTI KORUPSI PADA MATA PELAJARAN KIMIA MELALUI MEDIA GAME ULAR TANGGA

This research moved from the unfolding phenomenon of corruption cases in Indonesia which is on evidence of unsuccesfull education world. One of the efforts is to arouse creativity, confidence, and passion to always be productive, responsibility so as not provoke by committing cheating and instant acts. Here we need innovative learning models that can give rise to awareness of goodness. The purpose of this research is to find out the integration of anti corruption values of chemical subject in SMAN 13 Banda Aceh and implementing anti corruption value to the student since early stage through snake and ladders game. The subject of this research is students grade X-MIA first semester academic year 2014/2015, the total amount is 25 students wich consist of 14 male and 11 female. This research was conducted in two meetings. The first meeting is divided into two stages: first, 1 JP to implement anti values trough video and the next, 2 JP with chemical bonding material. Whereas in the second meeting, the first 2 JP for snakes and ladders and the following 1 JP is for evaluation. Based and the result of attitude assessment of there is only one student whose grades rated C, for psychomotor assessment, all students succeed while in cognitive assessment there are four students who have not reached the KKM 2.66 (B-) with students total presentage abaout chemical bonding material reached 84%. Through snake and ladders game it can implement anti corruption values to students since early stage. It can be seen that the learning process each student have shown core (honesty, discipline, responsibility), work ethic (hard work, shumble, and indipendent) and attitudes (fair, brave and caring).

Investigating the structural transitions of proteins during dissolution by mass spectrometry

An appropriate solvent environment is essential for the implementation of biological functions of proteins. Interactions between protein residues and solvent molecules are of great importance for proteins to maintain their active structure and catalyze biochemical reactions. In this study, we investigated such interactions and studied the structural transitions of proteins during their dissolution process. Our previously developed technique, namely solvent assisted electric field induced desorption/ionization, was used for the dissolution and immediate ionization of proteins. Different solvents and proteins were involved in the investigation. According to the results, cytochrome c underwent significant unfolding during dissolution in the most commonly used NH4Ac buffer. The unfolding got more serious when the concentration of NH4Ac was further increased. Extending the dissolution time resulted in the re-folding of cytochrome c. In comparison, no unfolding was observed if cytochrome c was pre-dissolved in NH4Ac buffer and detected by nano-ESI. Furthermore, no unfolding was observed during the dissolution process of cytochrome c in water. Interactions between the residues of cytochrome c and the solute of NH4Ac might be the reason for the unfolding phenomenon. Similar unfolding phenomenon was observed on holo-myoglobin. However, the observed dissolution feature of insulin was different. No unfolding was observed on insulin during dissolution in NH4Ac buffers. Insulin underwent observable unfolding when water was used for dissolution. This might be due to the structural difference between different proteins. The obtained results in the present study furthered our insights into the interactions between proteins and the solvents during the phase transition of dissolution.

Are Social Media Emancipatory or Hegemonic? Societal Effects of Mass Media Digitization in the Case of the SOPA Discourse

Mass media digitization is an unfolding phenomenon, posing novel societal opportunities and challenges that researchers are beginning to note. We build on and extend MIS research on process digitization and digital versus traditional communication media to study how and to what extent social media—one form of digital mass media—are emancipatory (i.e., permitting wide-spread participation in public discourse and surfacing of diverse perspectives) versus hegemonic (i.e., contributing to ideological control by a few). While a pressing concern to activists and scholars, systematic study of this issue has been elusive, owing partially to the complexity of the emancipation and hegemony concepts. Using a case study approach, we iteratively engaged with data on the discourse surrounding the Stop Online Piracy Act (SOPA) and source literature to identify six facets of interpretive media packages (i.e., competing social constructions of an issue) as measurable constructs pertinent to emancipation and hegemony. These facets included three structural constraints (on authorship, citation, and influence) and three content restrictions (on frames, signatures, and emotion). We investigated propositions regarding effects of social versus traditional media and lean versus rich social media on these interpretive media package facets by comparing the SOPA discourse across two lean traditional and social media (newspapers and Twitter) and two rich traditional and social media (television and YouTube). Our findings paradoxically revealed social media to be emancipatory with regard to structural constraints, but hegemonic with regard to an important content restriction (i.e., frames). Lean social media mitigated structural advantages and exacerbated content problems. These findings suggest that, as with traditional media, some inevitable evils accompany the societal benefits of social media and that mass media is having a detrimental effect on public discourse. We offer practical steps by which private and public institutions may counter this effect, theoretical implications for wider consideration of the six interpretive media package facets proposed here, and encouragement to MIS researchers to increase their efforts to compare different digitized processes so that a more comprehensive theory of the effects of different forms of digitized processes can be developed.

New institutional geographies of higher education: The rise of transregional university alliances

This article opens up debates about the deepening uneven geographies of higher education through a critical analysis of transregional university alliances. Focusing on the formation of research consortia and Doctoral Training Centres, we reveal the emergence of over 50 transregional alliances between United Kingdom universities. Despite each consortium operating at a variously defined regional scale there has been no explicit attempt to account for their geographical basis. Providing the first-ever analysis of this unfolding phenomenon, we demonstrate how the rise of transregional alliances is indicative of, and a response to, universities operating in an intensely neoliberalised political economy. Bringing together emergent theories of regionalism with emerging worlds of (neoliberal) higher education, our article reveals how, why and where universities are engaging in more intensively targeted, exclusive approaches to regional development. We argue that higher education is conducive to the weakening of fixed regional territories, and propose the metaphor of ‘regional constellations’ for interpreting transregional geographies. Finally, our analysis suggests that while high-performing research institutions may compete better by forming consortia, transregional alliances lead to a more unequal and divided university sector.

Bitcoin: The Early Market

&lt;p&gt;Bitcoin is a decentralized virtual crypto currency that has attracted attention from technologists, economists, consumers, regulators, black marketeers, venture capitalists and Wall Street commentators to name a few. While many debate issues such as whether or not bitcoin is money, how might it ultimately be regulated and whether or not it represents a truly disruptive innovation, this paper examines the current landscape of bitcoin and identifies some of the early adopters and significant events that have contributed to this unfolding phenomenon.&lt;/p&gt;

Surface-induced conformational changes in doped bovine serum albumin self-assembled monolayers.

Evidence for considerable stabilization of doped bovine serum albumin (BSA) molecules upon adsorption on gold surfaces is provided. This is compared to the surface-induced conformational changes of the bare BSA and its corresponding monolayer. The BSA unfolding phenomenon is correlated with dehydration, which in turn enables improved monolayer coverage. The stabilization mechanism is found to be partially controllable via nanodoping of the BSA molecules, upon which the dehydration process is suppressed and molecular rigidity can be varied. Our experimental data and calculations further point to the intermixing of structural characteristics and inherent molecular properties in studies of biological monolayers.

Structural stability and unfolding transition of β-glucosidases: a comparative investigation on isozymes from a thermo-tolerant yeast

The folding of proteins in the milieu of the cellular environment involves various interactions among the residues of the polypeptide chain and the microenvironment where it resides. These interactions are responsible for stabilizing the protein molecule, and disruption of the same provides information about the stability of the molecule. β-Glucosidase isozymes, despite having high homology in their primary and tertiary designs, show deviations in their properties such as unfolding, refolding, and stability. In a comparative study on two large cell-wall-bound isozymes, β-glucosidase I (BGLI) and β-glucosidase II (BGLII) from a thermo-tolerant yeast, Pichia etchellsii, we have investigated guanidine hydrochloride (GdnHCl)-induced, alkali-induced, and thermal-unfolding transitions using CD and fluorescence spectroscopy and high sensitivity differential scanning calorimetry. Using spectral parameters (MRE 222 nm) to monitor the conformational transitions of the GdnHCl-induced unfolding phenomenon, it was observed that the midpoints of unfolding, apparent C (m), occurred at 1.2 M ± 0.05 and 0.8 M ± 0.03 GdnHCl, respectively, for BGLI and BGLII. The alkali-induced unfolding process indicated that BGLI showed a mid-transition point at pH 11 ± 0.17, while for BGLII it was at pH 10 ± 0.40, further indicating BGLI to be more stable to alkali denaturation than BGLII. In the case of thermal unfolding, the midpoint of transition was observed at 63 ± 0.12°C for BGLI and at 58 ± 0.55°C for BGLII. Analysis by high sensitivity differential scanning calorimeter supported the unfolding data in which BGLI showed higher melting temperature, T (m), (56.07°C ± 0.34) than BGLII (54.02°C ± 0.36). Our results clearly indicate that BGLI is structurally more rigid and stable than BGLII.

Business ecosystem perspective on value co-creation in the Web 2.0 era: implications for entrepreneurial opportunities

Firms such as Facebook, Google and MySpace are rapidly emerging as leaders of what is known as the 'Web 2.0' era of commerce. The common distinguishing characteristic of these firms is the primary basis of the value they provide, namely a forum for iterative collaboration and interactive content creation and modification for users. Their strategies underlie an important, currently unfolding phenomenon – that of 'value co-creation' and a transformation in the way value is created and experienced by producers and consumers. It is the intent of this article to analyse this phenomenon and its implications for entrepreneurial opportunities. Drawing from an interdisciplinary body of literature in networked organisations, Web 2.0 technologies and innovation, we identify the trends driving this transformation, the process by which it is accomplished and its outcomes. Our analysis lays out a theoretically grounded explanation for the occurrence of value co-creation and consequent opportunities for entrepreneurship, and provides direction for future research.

Involvement of Single Residue Tryptophan 548 in the Quaternary Structural Stability of Pigeon Cytosolic Malic Enzyme

Pigeon cytosolic malic enzyme has a double dimer quaternary structure with three tryptophanyl residues in each monomer distributed in different structural domains. The enzyme showed a three-state unfolding phenomenon upon increasing the urea concentration (Chang, H. C., Chou, W. Y., and Chang, G. G. (2002) J. Biol. Chem. 277, 4663-4671). At urea concentration of 4-4.5 m, where the intermediate form was detected, the enzyme existed as partially unfolded dimers, which were easily polymerized. Mn2+ provided full protection against the polymerization. To further characterize this phenomenon, three mutants of the enzyme (W129, W321, and W548), each with only one tryptophanyl residue left, were constructed. All these mutants were successfully overexpressed in Escherichia coli cells and purified to homogeneity. Changes in the circular dichroism spectra of all mutants revealed a three-state urea-unfolding process in the absence of Mn2+. In the presence of 4 mm Mn2+, W548 and wild type (WT) enzymes shifted to monophasic, while W129 and W321 were still biphasic. Similar results were obtained from the fluorescence spectral changes, except for W321, which showed monophasic denaturation curve with or without Mn2+. Analytical ultracentrifugation analysis indicated that the mutant enzymes were polymerized at 4.5 m urea, and Mn2+ provided protective effect on W548 and WT enzymes only. Other mutants with mutated Trp-548 polymerized at 4.5 m urea in the absence or presence of 4 mm Mn2+. The above results indicate that a single residue, Trp-548, in the subunit interface region, is responsible for the integrity of the quaternary structure of the pigeon cytosolic malic enzyme.

Competitive Model on Denaturant-Mediated Protein Unfolding

A denaturant-mediated protein unfolding model, which is different from already existing ones based on the assumption that denaturant competes for water molecules to interact and thus reduces water–protein interactions, which leads to unfolding phenomenon, has been developed with a detailed mathematical justification. Theoretical results suggested that the parameter ( m u) obtained from the usual linear extrapolation model must be a linear function of the number of bound water molecules ( n) on protein with a zero intercept. However, application of this theory to a set of proteins for which m u values for urea denaturation are already known showed that m u was a linear function of n but with a nonzero intercept. Finally this nonzero intercept was attributed to binding of denaturant to protein at n = 0. Detailed investigation of this factor showed that average equilibrium constant for binding of urea with aromatic side chains (generally nonpolar side chains) was k b ≈ 0.65 ± 0.45 mol −1, which agreed well with earlier experimental estimations, and also suggested that an integrated approach was necessary to avoid discrepancy in Δ G H 2 O estimated from different models.