Complementary Theory Research Articles

Separating Uncertainty from Surprise in Auditory Processing with Neurocomputational Models: Implications for Music Perception.

Advances in neuroscience have led to the emergence of two complementary theories of neural information processing. First, the “Bayesian brain hypothesis” proposes that the brain actively predicts and represents incoming sensory information as probabilities that are updated in a near-optimal

Learning in deep neural networks and brains with similarity-weighted interleaved learning

Understanding how the brain learns throughout a lifetime remains a long-standing challenge. In artificial neural networks (ANNs), incorporating novel information too rapidly results in catastrophic interference, i.e., abrupt loss of previously acquired knowledge. Complementary Learning Systems Theory (CLST) suggests that new memories can be gradually integrated into the neocortex by interleaving new memories with existing knowledge. This approach, however, has been assumed to require interleaving all existing knowledge every time something new is learned, which is implausible because it is time-consuming and requires a large amount of data. We show that deep, nonlinear ANNs can learn new information by interleaving only a subset of old items that share substantial representational similarity with the new information. By using such similarity-weighted interleaved learning (SWIL), ANNs can learn new information rapidly with a similar accuracy level and minimal interference, while using a much smaller number of old items presented per epoch (fast and data-efficient). SWIL is shown to work with various standard classification datasets (Fashion-MNIST, CIFAR10, and CIFAR100), deep neural network architectures, and in sequential learning frameworks. We show that data efficiency and speedup in learning new items are increased roughly proportionally to the number of nonoverlapping classes stored in the network, which implies an enormous possible speedup in human brains, which encode a high number of separate categories. Finally, we propose a theoretical model of how SWIL might be implemented in the brain.

Copper adatoms mediated adsorption of benzotriazole on a gold substrate

The adsorption of organic molecules on metal surfaces is often mediated by metal adatoms, however their effect on the geometry of the resulting supramolecular structure can be difficult to determine. Herein, the role played by reactive copper atoms in the adsorption chemistry of benzotriazole (BTAH), an organic corrosion inhibitor for copper well-known for forming adatom mediated supramolecular structures, on an inert substrate, Au(111), has been investigated in an ultra-high vacuum environment using a combination of complementary surface sensitive techniques and density functional theory calculations. Pseudo-ordered and hydrogen bonded flat-lying assemblies convert into ordered -[CuBTA]n- flat-lying organometallic species of well-defined stoichiometry upon addition of copper atoms from the gas phase onto an Au(111) surface, which has been pre-dosed with BTAH. The formation and characterisation of these organometallic species are discussed in the light of the experimental results and computational modelling. The combination of complementary experimental and computational methods is crucial in order to obtain a thorough characterisation of such a complex system. The final supramolecular structure shows previously unseen BTA phases, which are favoured by the adsorption distribution of copper adatoms on Au(111), and are stable up to 500 K.

Digital consumption and socio-normative vulnerability

Digital consumption is expanding human boundaries and offering us unprecedented opportunities, while simultaneously redefining human capabilities, eroding individuality, and compromising ethical purpose; this is giving rise to a condition of digital consumerism through technological overdependence. Individuals' self-preserving autonomy, reasoning, ideologies, and ethical status are being compromised due to a growing compulsion for digital consumption, which is leading to the onset of digital harm. This study offers novel insights into the technological interventions that are giving rise to excessive digital consumption leading to digital harm. It also suggests how the effects of such harm can be mitigated through the lenses of two complementary theories: Self-determination theory (SDT) and Agentic theory. We identify five constructs of digital harm through epistemic discourse analysis and use thematic analysis to examine how the digital harm that affects individual rationality, maturity and autonomy can be mitigated by practising attributes of SDT and Agentic theory. This study shows the extent to which SDT and Agentic theory can help to explain how people collectively conceptualize, adapt, define and use the technology that constrains them as self-realizing rational beings.

Managing Group Dynamics and Effectiveness of University Staff: Evidence from Nigeria

Research evidence linking managing group dynamic (GPD) to the effectiveness of academic and non-academic staff of Nigerian universities, is ostensibly scarce. While existing studies have majorly addressed the performance impact of group dynamics in general perspectives, there is a gap in gauging how managing dynamics in groups could lead to the effectiveness of staff of Nigerian universities. Built on two complementary theories, the study has sought to investigate the relationship between pooled constructs of group dynamics, including social integration (SI), team leadership (TL), interpersonal facilitation (IF), group efficacy (GE); and effectiveness of university staff in those measures as in productivity (PD), adaptability (AD), and flexibility (FL). The sample size of 253 staff was selected from 2050 staff, and a self-structured questionnaire was designed. Instrument reliability was confirmed for the individual construct of GPD and staff effectiveness (SE) and Confirmatory Factor Analysis (CFA) which was used to validate the instruments. The frequency and percentage table, means, and standard deviations were engaged as descriptive tools. Linear and multiple regressions and variance inflation factor were designed to test hypotheses and relationships. Findings revealed a significant statistical relationship between the dimensions of GPD and measures of staff effectiveness except for the dimension of GPD (SI) with a weak aggregate predictive contribution. The study posited the need for management of the federal universities to forge integration with staff through adapting strategies of group dynamics to improve the effectiveness of academic and non-academic staff of universities. Especially, staff with innate creative ability and genius for innovation should be supported and motivated to reach their potential.

Abstract SY39-02: Accessing evolutionary programs to enable therapeutic resistance

Abstract Twenty million people around the world are diagnosed with cancer every year and over ten million people die because their cancer has metastasized and is incurable using current systemic therapies. Metastatic disease remains incurable because tumors evade all forms of programmed cell death. How is this possible? Unicellular and multicellular organisms have evolved multiple strategies to avoid death from internal and external stresses. While the nature of these catastrophes may be varied, their common property is to doom the organism unless it can access a survival mechanism and/or evolve a resistance mechanism rapidly. One such stress survival mechanism that is present across the tree of life in both unicellular and multicellular organisms is the utilization of a program that enables whole genome doubling (polyploidization) and cell cycle arrest. This evolutionary program allows the organism to avoid environmental stresses and protect the integrity of its genomic material by adopting a quiescent phenotype. In addition, by doubling DNA and increasing RNA and protein material, organisms have increased capacity to evolve further resistance mechanisms to stressors. To date, no common genomic signature has been defined that can explain or identify which patients will develop therapeutically resistant and lethal metastatic cancer. In all these incurable patients, therefore, lethal cancer independently evolves capacities for metastasis, avoidance of all cellular death pathways, and resistance. This convergent outcome across all patients demands an explanation beyond the accrual of stochastic mutations. Since the tumor ecosystem is exposed to constantly changing chemical and biologic conditions, it is generally assumed that cancer cell populations must have the ability to evolve rapidly to acquire mutations to adapt and survive. An alternative and complementary theory to explain cancer cell fitness is that a subset of cancer cells access evolutionary stress survival programs that are inherited as development programs. These development programs enable whole genome doubling (polyploidization) and cell cycle arrest and are seen in multiple cell types, including regenerating liver cells, myocytes under physical strain, and megakaryocytes under metabolic stress. In cancer, access to these stress programs result in cancer cell survival though a state of cell cycle arrest that is simultaneously polyploid and aneuploid. Entering the polyaneuploid cancer cell (PACC) state, cancer cells pause their cell cycle and protect the integrity of their DNA from tumor microenvironmental stresses as well as have increased potential to develop further resistance mechanisms to environmental stressors and toxic therapies. After stress is removed, cells in the PACC state undergo depolyploidization and generate resistant progeny. This enables the generation of heritable variation that can be dispensed to their 2N+ aneuploid progeny, providing population rescue in response to therapeutic stress. Targeting cells in the PACC state opens a new avenue for cancer therapy. Citation Format: Kenneth J. Pienta. Accessing evolutionary programs to enable therapeutic resistance [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr SY39-02.

The touch-screen generation: Trends in Dutch parents’ perceptions of young children’s media use from 2012–2018

Abstract Based on a time-lag model, this study tested for changes in young children’s (1–6 years) home access and use of digital media in the 2012–2018 period as well as in their parents’ views on such media. What it found was that in only a few years the digital devices available to children have become more mobile (tablets and smartphones), more accessible, and more numerous in these children’s bedrooms, especially in single-parent households. Also, on average children have strongly increased their daily media use—up to 102 minutes. This is especially true for both younger children (3 years or less, plus 30 minutes) and children in middle to highly educated households (plus 25 minutes). Our findings support the complementary media adoption theory more than the displacement theory. Over the years parents have tended more and more to use digital media as ‘babysitters’, while they also found it increasingly difficult to stop their children from using such media, which may have major implications for parenting support activities.

Diamond (111) surface reconstruction and epitaxial graphene interface

The evolution of the diamond (111) surface as it undergoes reconstruction and subsequent graphene formation is investigated with angle-resolved photoemission spectroscopy, low energy electron diffraction, and complementary density functional theory calculations. The process is examined starting at the C(111)-(2x1) surface reconstruction that occurs following detachment of the surface adatoms at 920 {\deg}C, and continues through to the liberation of the reconstructed surface atoms into a free-standing monolayer of epitaxial graphene at temperatures above 1000 {\deg}C. Our results show that the C(111)-(2x1) surface is metallic as it has electronic states that intersect the Fermi-level. This is in strong agreement with a symmetrically {\pi}-bonded chain model and should contribute to resolving the controversies that exist in the literature surrounding the electronic nature of this surface. The graphene formed at higher temperatures exists above a newly formed C(111)-(2\times1) surface and appears to have little substrate interaction as the Dirac-point is observed at the Fermi-level. Finally, we demonstrate that it is possible to hydrogen terminate the underlying diamond surface by means of plasma processing without removing the graphene layer, forming a graphene-semiconductor interface. This could have particular relevance for doping the graphene formed on the diamond (111)surface via tuneable substrate interactions as a result of changing the terminating species at the diamond-graphene interface by plasma processing.

Abstract IA017: The polyaneuploid cancer cell state as a mediator of therapeutic resistance

Abstract More than ten million people around the world will die from metastatic cancer in 2022. To date, no common genomic signature has been defined that can explain or identify which patients will develop lethal metastatic cancer. In all of these incurable patients lethal cancer independently evolves capacities for metastasis, avoidance of all cellular death pathways, and resistance. This convergent outcome demands an explanation beyond the slow and steady accrual of stochastic mutations. Generally, it is thought that cancer cells utilize the forces of natural selection when utilizing accumulating mutations during its evolution. Their utilization of heritable variation permits the cancer cell population to respond and survive environmental hazards. The tumor ecosystem is exposed to extreme and constantly changing chemical conditions. These changes can be natural, (e.g., loss of blood supply) or imposed (therapeutic). While the nature of these catastrophes may be varied or unique, their common property may be to doom the current cancer phenotype unless it evolves rapidly. We propose a complementary theory to explain cancer cell fitness through these environmental hazards that lead to metastasis, therapeutic resistance, and lethality. The basis of this theory is that a subset of cancer cells accesses evolutionary or developmental (evo/devo) stress survival programs that enable whole genome doubling (polyploidization) and cell cycle arrest. These stress survival programs are observed across the tree of life, from unicellular both prokaryotes and eukaryotes, such as Archaea, Bacteria, and yeast, to multicellular organism including plants and animals. In cancer, environmental stress and these stress programs result in cancer cell survival though a state of cell cycle arrest that is simultaneously polyploid and aneuploid. During this polyaneuploid cancer cell (PACC) state, cancer cells pause their cell cycle and protect the integrity of their DNA. This avoids the environmental stresses associated with the tumor microenvironment and metastatic cascade as well as the toxic effects of systemic therapy. In addition, by doubling their DNA and increasing their RNA and protein material, cancer cells in the PACC state have increased potential to develop further resistance mechanism to environmental stressors and otherwise toxic therapies. We have demonstrated that upon removal of stress, e.g., chemotherapy, cells in the PACC state undergo depolyploidization and generate resistant progeny. Thus, cells in the PACC state may play a critical role in lethality by their increased capacity to endure novel and stressful environments. This enables the metastatic phenotype and the generation of heritable variation that can be dispensed to their 2N+ aneuploid progeny, providing population rescue in response to therapeutic stress. Targeting cells in the PACC state is essential to cancer therapy and patient cure. Citation Format: Kenneth J. Pienta. The polyaneuploid cancer cell state as a mediator of therapeutic resistance [abstract]. In: Proceedings of the AACR Special Conference on the Evolutionary Dynamics in Carcinogenesis and Response to Therapy; 2022 Mar 14-17. Philadelphia (PA): AACR; Cancer Res 2022;82(10 Suppl):Abstract nr IA017.

Understanding the complementarities of surface-enhanced infrared and Raman spectroscopies in CO adsorption and electrochemical reduction

In situ/operando surface enhanced infrared and Raman spectroscopies are widely employed in electrocatalysis research to extract mechanistic information and establish structure-activity relations. However, these two spectroscopic techniques are more frequently employed in isolation than in combination, owing to the assumption that they provide largely overlapping information regarding reaction intermediates. Here we show that surface enhanced infrared and Raman spectroscopies tend to probe different subpopulations of adsorbates on weakly adsorbing surfaces while providing similar information on strongly binding surfaces by conducting both techniques on the same electrode surfaces, i.e., platinum, palladium, gold and oxide-derived copper, in tandem. Complementary density functional theory computations confirm that the infrared and Raman intensities do not necessarily track each other when carbon monoxide is adsorbed on different sites, given the lack of scaling between the derivatives of the dipole moment and the polarizability. Through a comparison of adsorbed carbon monoxide and water adsorption energies, we suggest that differences in the infrared vs. Raman responses amongst metal surfaces could stem from the competitive adsorption of water on weak binding metals. We further determined that only copper sites capable of adsorbing carbon monoxide in an atop configuration visible to the surface enhanced infrared spectroscopy are active in the electrochemical carbon monoxide reduction reaction.

H trapping at the metastable cation vacancy in α-Ga2O3 and α-Al2O3

α-Ga2O3 has the corundum structure analogous to that of α-Al2O3. The bandgap energy of α-Ga2O3 is 5.3 eV and is greater than that of β-Ga2O3, making the α-phase attractive for devices that benefit from its wider bandgap. The O–H and O–D centers produced by the implantation of H+ and D+ into α-Ga2O3 have been studied by infrared spectroscopy and complementary theory. An O–H line at 3269 cm−1 is assigned to H complexed with a Ga vacancy (VGa), similar to the case of H trapped by an Al vacancy (VAl) in α-Al2O3. The isolated VGa and VAl defects in α-Ga2O3 and α-Al2O3 are found by theory to have a “shifted” vacancy-interstitial-vacancy equilibrium configuration, similar to VGa in β-Ga2O3, which also has shifted structures. However, the addition of H causes the complex with H trapped at an unshifted vacancy to have the lowest energy in both α-Ga2O3 and α-Al2O3.

CORRIGENDUM to “Psychological Antecedents of Intentions to Participate in Last Chance Tourism: Considering Complementary Theories”

CORRIGENDUM to “Psychological Antecedents of Intentions to Participate in Last Chance Tourism: Considering Complementary Theories”

Integrating the dialectic perspectives of resource-based view and industrial organization theory for competitive advantage – a review and research agenda

PurposeAcademic dialogue related to ‘organizational performance’ in strategic management has primarily centred around the industrial organization theory (IO) and resource-based view (RBV). Both perspectives, though conceptually dialectic, have served as primary competing theories governing research studies in the domain of strategic management. However, the confluence of these theoretical perspectives has not been adequately explored to advance a shared view of competitive advantage. This study aims to explore the likelihood of embedded commonalities between RBV and IO.Design/methodology/approachA bibliometric analysis was conducted to visualize the intellectual map of studies and knowledge development encompassing these theories. This was followed by a comprehensive literature review to understand how the business environment (BE) and organizational capabilities have contributed towards attaining competitive advantage.FindingsThis study established that connecting the intellectual boundaries of these theoretical perspectives would facilitate better comprehension of the processes and outcomes in organizations. Integrating the knowledge emerging out of this methodological blend, a convergence framework connecting the intellectual boundaries of both theories was presented.Practical implicationsThe framework that emerged from this study would help in better understanding of organizational behaviour from a dual theoretical lens. It would also motivate future studies to consider RBV and IO as complementary theories rather than the current narrative of competing theories.Social implicationsThis study added to the efforts to achieve equilibrium between the BE and internal capabilities of organizations so as to maximize positive social externalities.Originality/valueThis study contributed to the limited attempts to leverage shared knowledge from a dual perspective using a comprehensive literature review in sequential combination with bibliometric analysis.

The Development of Lean Healthcare Constructs for Quality of Healthcare Service: A Second-order Model of Lean Healthcare in Malaysia

The increase of patients’ attendance due to Covid-19 cases, together with the rise of patients’ demand, long waiting time, rising cost of service, lack of quality personnel and government funding constraints has overwhelmed the healthcare system and resources. Lean is therefore introduced as one of the best strategies by improving the quality of healthcare service delivery through stakeholders’ centricity. Despite there are emerging literatures for Lean healthcare, there is less agreement on the primary constructs constituting under the Lean healthcare practices. This study aims to identify the Lean healthcare practices and provide valid and reliable constructs for Lean healthcare in Malaysia. With the inspiration of Complementary Theory and Sustainable Lean Iceberg Model, the Lean healthcare is conceptualized as second-order formatively measured construct with five first-order constructs namely Strategy and alignment; Leadership; Behavior and engagement; Process management; Tools, technologies and techniques and measure Lean healthcare association with healthcare service quality. Data were obtained from 500 healthcare practitioners and patients in Malaysia public lean hospitals. The result identified the valid and reliable Lean healthcare constructs which consists of five Lean healthcare practices with total 30 items. The study found that all the constructs are complementary and mutually supportive to present the Lean healthcare as holistic implementation and have significant association with the healthcare service quality. This study provides fundamental knowledge and direction for future research as well as practitioners to adopt and implement all the Lean healthcare practices in a holistic manner to enhance the quality of healthcare services.

Research on the Productivity Paradox of Information Technology

The rapid development of new-generation information technology, such as the internet, big data, and artificial intelligence, has shifted the focus of theoretical and commercial attention on whether information technology can increase productivity growth. This paper systematically combs the evolution trend of the productivity paradox of information technology from the macro and micro levels. The findings revealed that there are still no unified conclusions at the macro-level, but it is generally believed that there is no productivity paradox at the micro level. There are some differences between developed and non-developed countries as well as across different industries. Based on the complementary mechanism theory, it is found that information technology forms a complementary effect with human capital, technological innovation, organizational change, and management practice, which can provide ideas for solving the productivity paradox of information technology. Finally, the future research direction for the productivity paradox of information technology is determined from the macro and micro levels.

Magnetic-Field-Induced Dielectric Anomalies in Cobalt-Containing Garnets.

Here we present a comparative study of the magnetic and crystal chemical properties of two Co2+ containing garnets. CaY2Co2Ge3O12 (which has been reported previously) and NaCa2Co2V3O12 both exhibit the onset of antiferromagnetic order around 6 K as well as field-induced transitions around 7 and 10 T, respectively, that manifest as anomalies in the dielectric properties of the material. We perform detailed crystal-chemistry analyses and complementary density functional theory calculations to show that very minor changes in the local environment of the Co ions explain the differences in the two magnetic structures and their respective properties.

Reduction of Transition-Metal Columbite-Tantalite as a Highly Efficient Electrocatalyst for Water Splitting

We successfully report a liquid-liquid chemical reduction and hydrothermal synthesis of a highly stable columbite-tantalite electrocatalyst with remarkable hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) performance in acidic media. The reduced Fe0.79Mn0.21Nb0.16Ta0.84O6 (CTr) electrocatalyst shows a low overpotential of 84.23 mV at 10 mA cm-2 and 103.7 achieved at 20 mA cm-2 current density in situ for the HER and OER, respectively. The electrocatalyst also exhibited low Tafel slopes of 104.97 mV/dec for the HER and 57.67 mV/dec for the OER, verifying their rapid catalytic kinetics. The electrolyzer maintained a cell voltage of 1.5 V and potential-time stability close to that of Pt/C and RuO2. Complementary first-principles density functional theory calculations identify the Mn sites as most active sites on the Fe0.75Mn0.25Ta1.875Nb0.125O6 (100) surface, predicting a moderate Gibbs free energy of hydrogen adsorption (ΔGH* ≈ 0.08 eV) and a low overpotential of η = 0.47 V. The |ΔGMnH*| = 0.08 eV on the Fe0.75Mn0.25Ta1.875Nb0.125O6 (100) surface is similar to that of the well-known and highly efficient Pt catalyst (|ΔGPtH*| ≈ 0.09 eV).

The influence of chemistry on the interface toughness in a WTi-Cu system

With a considerable amount of commonly used material systems consisting of individual, rather confined layers, the question for mechanical behaviour of their individual interfaces arises. Especially, when considering varying interfacial structures as a result of the processing environment. Furthermore, the interaction between pronounced plasticity and fracture processes can lead to challenges with regards to separation between sole interface- or bulk properties.The present work investigates the interfacial fracture characteristic of a WTi-Cu sytem commonly found in the microelectronics industry as a heterogeneous model material with pronounced plasticity in the Cu phase. To study this behaviour on a rather limited scale (<6 µm), microcantilever experiments were conducted and evaluated using a continuous J-Δa curve evaluation scheme with classical elastic-plastic considerations in mind. A change in interface chemistry, resulting from air exposure between processing steps, was probed and found to show distinct crack propagation along the interface opposed to crack tip blunting as encountered in the vacuum processed sample. Complementary density functional theory calculations also showed a strong reduction of interface cohesion upon oxygen accumulation and a model framework based on classical dislocation plasticity considerations revealed the transition from plasticity to fracture processes to be a result of shielding and following change in mode mixity.

In search of a definition and frameworks for engineering leadership development.

Despite an elusive definition of engineering leadership, educators and researchers forge ahead to identify disparate and complementary theories which frame engineering leadership.

Effect of neutron irradiation on ductility of tungsten foils developed for tungsten-copper laminates

Severe plastic deformation of tungsten (W) is known to be an efficient way to reduce its inherently high ductile-to-brittle transition temperature (DBTT), what is essential for its use in components of a fusion reactor. Thin rolled W foils possess superior mechanical behaviour at room temperature (RT), as demonstrated in previous works. It was then proposed to expand the beneficial mechanical properties of the foil to bulk by fabricating tungsten-copper (W-Cu) laminate composites, which can be used for structural applications. Neutron irradiation in HFIR resulted in embrittlement of the laminate already after 0.016dpa, with the W foil determining the composite behaviour.In this work, for the first time, we investigate the effect of neutron irradiation on individual W foil, and determine the resulting DBTT shift with the help of cantilever bend tests, using bulk W and the W-Cu composite as reference. The W foil and the bulk samples were irradiated to 0.15dpa at 400 °C in the BR-2 reactor in Mol (Belgium). We also hypothesise that diffusion of Cu atoms into W could modify the response to irradiation in these materials. We substantiate it with complementary density functional theory (DFT) ab initio calculations to analyse the Cu-vacancy and Cu-self-interstitial interaction, which helps to elucidate co-alignment of the fluxes of point defects and Cu solutes in W matrix.Irradiated foil was found to retain its ductility at RT. No significant irradiation hardening or DBTT shift were detected in the irradiated W foil compared to the bulk W. The different irradiation effect on embrittlement in individual foils and in the laminate may be attributed to the irradiation-assisted diffusion of Cu solutes in W foil, which could form intermetallic phases and affect the accumulation of lattice defects.