Role Of Core Research Articles

Growth defect of domain III glycoprotein B mutants of human cytomegalovirus reverted by compensatory mutations co-localizing in post-fusion conformation.

Cell entry is a crucial step for a virus to infect a host cell. Human cytomegalovirus utilizes glycoprotein B (gB) to fuse the viral and host cell membranes upon receptor binding of gH/gL-containing complexes. Fusion is mediated by major conformational changes of gB from a metastable pre-fusion to a stable post-fusion state whereby the central trimeric coiled-coils, formed by domain (Dom)III α helices, remain structurally nearly unchanged. To better understand the role of the stable core, we individually introduced three potentially helix-breaking or one disulfide bond-breaking mutation in the DIII α3 to study different aspects of the viral behavior upon long-term culturing. Two of the three helix-breaking mutations, gB_Y494P and gB_I495P, were lethal for the virus in either fibroblasts or epithelial cells. The third substitution, gB_G493P, on the other hand, displayed a delayed replication and spread, which was more pronounced in epithelial cells, hinting at an impaired fusion. Interestingly, the disulfide bond-breaker mutation, gB_C507S, performed strikingly differently in the two cell types - lethal in epithelial cells and an atypical phenotype in fibroblasts, respectively. Replication curve analyses paired with the infection efficiency, the spread morphology, and the cell-cell fusogenicity suggest a dysregulated fusion process, which could be reverted by second-site mutations mapping predominantly to gB DomV. Our findings underline the functional importance of a stable DomIII core for a well-regulated DomV rearrangement during fusion.IMPORTANCEHuman cytomegalovirus (HCMV) can establish a lifelong infection. In most people, the infection follows an asymptomatic course; however, it is a major cause of morbidity and mortality in immunocompromised patients or neonates. HCMV has a very broad cell tropism, ranging from fibroblasts to epi- and endothelial cells. The virus uses different entry pathways utilizing the core fusion machinery consisting of glycoprotein complexes gH/gL and glycoprotein B (gB). The fusion protein gB undergoes fundamental rearrangements from a metastable pre-fusion to a stable post-fusion conformation. Here, we characterized the viral behavior after the introduction of four single-point mutations in the gB central core. These led to various cell type-specific atypical phenotypes and the emergence of compensatory mutations, demonstrating an important interaction between domains III and V. We provide a new basis for the development of a structurally and functionally altered gB, which can further serve as a tool for drug and vaccine development.

Propofol disrupts the functional core-matrix architecture of the thalamus in humans

Research into the role of thalamocortical circuits in anesthesia-induced unconsciousness is difficult due to anatomical and functional complexity. Prior neuroimaging studies have examined either the thalamus as a whole or focused on specific subregions, overlooking the distinct neuronal subtypes like core and matrix cells. We conducted a study of heathy volunteers and functional magnetic resonance imaging during conscious baseline, deep sedation, and recovery. We advanced the functional gradient mapping technique to delineate the functional geometry of thalamocortical circuits, within a framework of the unimodal-transmodal functional axis of the cortex. Here we show a significant shift in this geometry during deep sedation, marked by a transmodal-deficient geometry. This alteration is closely linked to the spatial variations in the matrix cell composition within the thalamus. This research bridges cellular and systems-level understanding, highlighting the crucial role of thalamic core–matrix functional architecture in understanding the neural mechanisms of states of consciousness.

Geographic location shapes fungal communities associated with Epidendrum roots

Fungal biodiversity significantly influences ecosystem dynamics through various interactions with plants, ranging from pathogenic to mutually beneficial associations. This study explores the fungal diversity associated with an ornamental orchid genus Epidendrum that is widely propagated globally but native to northern South America. Root samples were collected from Epidendrum in diverse geographic locations: Brazil, Colombia, Germany, Spain and six South African provinces. Fungal biodiversity was catalogued from the genomic DNA extracted from these roots using fungal-specific primers and Illumina MiSeq sequencing. Bioinformatic and statistical analyses revealed significant fungal diversity in the roots, with distinct dominant orders in each geographic region. Among the South African samples, significant differences were found in alpha diversity indices and species richness. Even though samples originating from different provinces overlapped in the PCoA plot, PERMANOVA indicated a significant difference in the fungal biodiversity, which was further supported by PERMDISP. In the global dataset, alpha diversity indices were insignificant, but species richness was. In the PCoA plot, data points clustered by sampling sites, indicating substantial differences in fungal biodiversity between the samples. This was validated by PERMANOVA and PERMDISP analyses. Outcomes from the core fungal analyses showed Epidendrum retained a conserved set of fungal orders from its native habitat when it transitioned to exotic regions, while it also formed new associations with local fungal communities in these introduced regions. These findings highlight the role of both core and region-specific fungal communities in the ecological adaptability and success of this widely planted orchid genus.

Structural and functional dissection of the Pacinian corpuscle reveals an active role of the inner core in touch detection.

Pacinian corpuscles are rapidly adapting mechanoreceptor end-organs that detect transient touch and high-frequency vibration. In the prevailing model, these properties are determined by the outer core, which acts as a mechanical filter limiting static and low-frequency stimuli from reaching the afferent terminal-the sole site of touch detection in corpuscles. Here, we determine the detailed 3D architecture of corpuscular components and reveal their contribution to touch detection. We show that the outer core is dispensable for rapid adaptation and frequency tuning. Instead, these properties arise from the inner core, composed of gap junction-coupled lamellar Schwann cells (LSCs) surrounding the afferent terminal. By acting as additional touch sensing structures, LSCs potentiate mechanosensitivity of the terminal, which detects touch via fast-inactivating ion channels. We propose a model in which Pacinian corpuscle function is mediated by an interplay between mechanosensitive LSCs and the afferent terminal in the inner core.

Life Skills for Promoting Mental Well-Being among Indian Adolescents and Youth

Abstract: Adolescents and young emerging adults are highly vulnerable to stress and strain due to numerous transitions which are biological, socio-emotional, and psychological in nature. This coupled with external factors and environmental influences such as family structure and needs, peer-pressure, school and college environment play a critical role in influencing their thoughts and behavior. Hence it becomes crucial to find the means for strengthening problem-solving skills thereby enhancing their mental health and overall well-being. Life skills serve as an effective means of empowering adolescents and youth to navigate life’s challenges proficiently, using a skill-based approach. The World Health Organization (WHO) focuses on ten core life skills including aspects of individual personality (self-awareness, empathy), cognitive skills (critical and creative thinking, decision making, problem solving), coping skills (coping with stress and emotions), interpersonal relationships and communication skills. The Jeevan Kaushal Curriculum (2.0) framed by University Grants Commission proposes several core skills essential for living successful lives viz. communication skills, professional skills (career and team skills), leadership and management skills and universal human values. This study attempts to explore the role of core documents such as the Jeevan Kaushal Curriculum (2.0), WHO Universal Health Coverage for Mental Health and National Education Policy (NEP, 2020) in supporting the mental well-being of the target population, using document analysis. The study findings indicate that the Jeevan Kaushal curriculum (2.0) can be used as an effective tool towards fostering student skills sets and enhancing mental strength thereby supporting the promotion and maintenance of mental well-being of adolescents and youth in the Indian context. Moreover, it is in alignment with the core features of NEP 2020 which focuses on a holistic, transformational higher education curriculum incorporating value-based education and community engagement services.

When the dark one negotiates: Sacrificing relations at the altar of money

While evidence suggests the significant role played by personality traits in affecting the usage of inappropriate and unethical negotiation strategies, studies have rarely examined the dark core. Considering, negotiation frequently involves choosing between economic outcomes and relational gains, this research primarily examines the effect of dark core and the mediating role of relational interdependent self-construal (RISC) in affecting the usage of inappropriate negotiation strategies (SINS), at the person level (Study – 1) (n = 283, managers, India). Further, it evaluates the individual and interactive effect of dark core with two situation level variables, namely, Interdependence and Incentives in a dictator game design (Study – 2) (n = 221, business school postgraduates, India). It was observed that, while at the person level, the effects of dark core were significantly mediated by RISC, at the situational level, the increasing degree of interdependence with the actor and the additional economic incentives offered, significantly interacted with dark core to predict the endorsement of a variety of inappropriate negotiation strategies. In summary, the study examines the role of dark core, clarifies its self – interested nature, propensity for favouring economic gains at the cost of deteriorated relationships and highlights the role of two important situational elements in negotiation.

SYMBOLIC METAMETAPHORS IN BORGES' "THE HOUSE OF ASTERION"

The paper examines metametaphors in Borges' "The House of Asterion", focusing on reconstructing symbolic metametaphors and derivative metaphorical constructs within a postmodernist and existentialist framework. It highlights the role of metaphorical core and periphery in encoding the narrative-semiotic structure. The study reveals that metametaphors serve as codes for interpreting and integrating images and meanings, aligning with symbolic metaphorical constants in postmodern and existential-philosophical texts.

Involvement of Pre-limbic Cortex-Nucleus accumbens projections in Context-Induced alcohol seeking

Alcohol use disorder (AUD) remains a critical public health issue worldwide, characterized by high relapse rates often triggered by contextual cues. This research investigates the neural mechanisms behind context-induced reinstatement of alcohol-seeking behavior, focusing on the nucleus accumbens and its interactions with the prelimbic cortex, employing Male Long-Evans rats in an ABA renewal model. In our experimental setup, rats were trained to self-administer 10 % ethanol in Context A, followed by extinction of lever pressing in the presence of discrete cues in Context B. The context-induced reinstatement of ethanol-seeking was then assessed by re-exposing rats to Context A or B under extinction conditions, aiming to simulate the environmental cues’ influence on relapse behaviors. Three experiments were conducted: Experiment 1 utilized Fos-immunohistochemistry to examine neuronal activation in the nucleus accumbens; Experiment 2 applied the baclofen + muscimol inactivation technique to probe the functional importance of the nucleus accumbens core; Experiment 3 used Fos-immunofluorescence along with Retrobeads injection to investigate activation of neurons projecting from the prelimbic cortex to the nucleus accumbens core. Our findings revealed significant increases in Fos-immunoreactive nuclei within the nucleus accumbens core and shell during the reinstatement phase in Context A, underscoring the environment’s potent effect on ethanol-seeking behavior. Additionally, inactivation of the nucleus accumbens core markedly reduced reinstatement, and there was a notable activation of neurons from the prelimbic cortex to the nucleus accumbens core in the ethanol-associated context. These results highlight the critical role of the nucleus accumbens core and its corticostriatal projections in the neural circuitry underlying context-driven ethanol seeking.

A network-based modeling framework reveals the core signal transduction network underlying high carbon dioxide-induced stomatal closure in guard cells.

Stomata are pores on plant aerial surfaces, each bordered by a pair of guard cells. They control gas exchange vital for plant survival. Understanding how guard cells respond to environmental signals such as atmospheric carbon dioxide (CO2) levels is not only insightful to fundamental biology but also relevant to real-world issues of crop productivity under global climate change. In the past decade, multiple important signaling elements for stomatal closure induced by elevated CO2 have been identified. Yet, there is no comprehensive understanding of high CO2-induced stomatal closure. In this work, we assemble a cellular signaling network underlying high CO2-induced stomatal closure by integrating evidence from a comprehensive literature analysis. We further construct a Boolean dynamic model of the network, which allows in silico simulation of the stomatal closure response to high CO2 in wild-type Arabidopsis thaliana plants and in cases of pharmacological or genetic manipulation of network nodes. Our model has a 91% accuracy in capturing known experimental observations. We perform network-based logical analysis and reveal a feedback core of the network, which dictates cellular decisions in closure response to high CO2. Based on these analyses, we predict and experimentally confirm that applying nitric oxide (NO) induces stomatal closure in ambient CO2 and causes hypersensitivity to elevated CO2. Moreover, we predict a negative regulatory relationship between NO and the protein phosphatase ABI2 and find experimentally that NO inhibits ABI2 phosphatase activity. The experimental validation of these model predictions demonstrates the effectiveness of network-based modeling and highlights the decision-making role of the feedback core of the network in signal transduction. We further explore the model's potential in predicting targets of signaling elements not yet connected to the CO2 network. Our combination of network science, in silico model simulation, and experimental assays demonstrates an effective interdisciplinary approach to understanding system-level biology.

Tuning Electron-Accepting Properties of Phthalocyanines for Charge Transfer Processes.

Phthalocyanines play fundamental roles as electron-acceptors in many different fields; thus, the study of structural features affecting electron-accepting properties of these macrocycles is highly desirable. A series of low-symmetry zinc(II) phthalocyanines, in which one, three, or four benzene rings were replaced for pyrazines, was prepared and decorated with electron-neutral (alkylsulfanyl) or strongly electron-withdrawing (alkylsulfonyl) groups to study the role of the macrocyclic core as well as the effect of peripheral substituents. Electrochemical studies revealed that the first reduction potential (Ered1) is directly proportional to the number of pyrazine units in the macrocycle. Introduction of alkylsulfonyl groups had a very strong effect and resulted in a strongly electron-deficient macrocycle with Ered1 = -0.48 V vs SCE (in THF). The efficiency of intramolecular-charge transfer (ICT) from the peripheral bis(2-methoxyethyl)amine group to the macrocycle was monitored as a decrease in the sum of ΦΔ + ΦF and correlated well with the determined Ered1 values. The strongest quenching by ICT was observed for the most electron-deficient macrocycle. Importantly, an obvious threshold at -1.0 V vs SCE was observed over which no ICT occurs. Disclosed results may substantially help to improve the design of electron-donor systems based on phthalocyanines.

Educational reconstruction of physics of complexity within a creative writing classroom activity

Disciplinary identity is widely studied in physics (and science) education research. Great attention has been devoted to studying the role of sociocultural factors in students’ career choices and persistence, such as students’ participation or gender differences. However, few works within the literature have investigated the role of the cognitive-epistemic core of scientific disciplines in identity work. In the first section of the paper we discuss the state of the art about science-identity. Then, we discuss the theoretical frameworks that informed the construction of our idea of epistemic-personal consonance/dissonance: the “Reconceptualized FRA to NOS framework” and the “Model of Educational Reconstruction”. In section 4 we introduce a qualitative analysis of data collected within a classroom activity held in 2021 and discuss it according to our Research Question. The findings show that students used complex systems epistemology as scaffolding for the expression of personal needs; they reconceptualized personal demands by borrowing epistemological structures and practices of complexity as tools to change perspectives about personal issues. The findings of this first dataset call for the need for further data to analyze and enrich the discussion around physics epistemology and identity.

Benzopyrone, a privileged scaffold in drug discovery: An overview of FDA-approved drugs and clinical candidates.

Natural products have always served as an important source of drugs for treating various diseases. Among various privileged natural product scaffolds, the benzopyrone class of compounds has a substantial presence among biologically active compounds. One of the pioneering anticoagulant drugs, warfarin approved in 1954 bears a benzo-α-pyrone (coumarin) nucleus. The widely investigated psoriasis drugs, methoxsalen, and trioxsalen, also contain a benzo-α-pyrone nucleus. Benzo-γ-pyrone (chromone) containing drugs, cromoglic acid, and pranlukast were approved as treatments for asthma in 1982 and 2007, respectively. Numerous other small molecules with a benzopyrone core are under clinical investigation. The present review discusses the discovery, absorption, distribution, metabolism, excretion properties, and synthetic approaches for the Food and Drug Administration-approved and clinical-stage benzopyrone class of compounds. The role of the pyrone core in biological activity has also been discussed. The present review unravels the potential of benzopyrone core in medicinal chemistry and drug development.

Influence of the ion core on relaxation processes in dense plasmas

AbstractThe effect of an ionic core on the temperature relaxation in dense hot plasma of beryllium is studied using the pseudpotential model by Gericke et al [Phys. Rev. E 2010, 81, 065401(R)]. Employing the screened version of the ion pseudpotential [by Ramazanov et al, Phys. Plasmas 2021, 28 (9), 092702], we computed the quantum transport cross section for the electron‐ion collisions in dense beryllium plasma, where screening is taking into account using the density response function in the long‐wavelength regime. The results for the transport cross section are used to compute a generalised Coulomb logarithm and electron‐ion collision frequency. Utilizing the latter, we show the effect of the ionic core on the temperature relaxation. To understand the role of the ionic core, we compare the results with the data computed considering ions as point‐like charges.

Nucleus accumbens core dopamine D2 receptors are required for performance of the odor span task in male rats.

The nucleus accumbens (NAc) core gates motivationally relevant behavioral action sequences through afferents from cortical and subcortical brain regions. While the role of the NAc core in reward and effort-based decision making is well established, its role in working memory (WM) processes is incompletely understood. The odor span task (OST) has been proposed as a measure of non-spatial working memory capacity (WMC) as it requires rodents to select a novel odor from an increasing number of familiar odors to obtain a food reward. To assess the role of the NAc core in the OST using (1) reversible chemical inactivation and (2) selective blockade of dopamine D1 and D2 receptors in the area. Well-trained male rats were tested on the OST following intra-NAc core infusions of muscimol/baclofen, the D1 receptorantagonist SCH-23390 (1 μg/hemisphere) and the D2 receptorantagonist eticlopride (1 μg/hemisphere). Behavioral measurements included the average odor span, maximum odor span, choice latency, searching vigor, and patterns of responding during foraging that may relate to impulsivity. Chemical inactivation of the NAc core significantly decreased odor span relative to sham and vehicle conditions. Selective antagonism of D2, but not D1, receptors in the NAc core also produced deficits in odor span. We found that secondary behavioral measures of choice latency, searching vigor, and responding to the first odor stimulus encountered were largely unaffected by treatment. These findings suggest that D2 receptors in the NAc core are required for OST performance.

Mechanistic elucidation of the catalytic activity of silver nanoclusters: exploring the predominant role of electrostatic surface.

The core and the ligand shell of metal nanoclusters (MNCs) have an influential role in modulating their spectroscopic signatures and catalytic properties. The aspect of electrostatic interactions to regulate the catalytic properties of MNCs has not been comprehensively addressed to date. Our present work conclusively delineates the role of the metal core and the electrostatic surface of MNCs involved in the reduction of nitroarenes. A facile surface modification of mercaptosuccinic acid (MSA)-templated AgNCs has been selectively achieved through Mg2+ ions (Mg-AgNCs). Microscopic studies suggest that the size of Mg-AgNCs is ∼3.3 nm, which is considerably higher than that of MSA-templated AgNCs (∼1.75 nm), confirming the formation of a nano-assembled structure. Our spectroscopic and microscopic experiments revealed that the negatively charged AgNCs efficiently catalyze the reduction of 4-nitrophenol (4-NP) with a rate constant of 0.23 ± 0.01 min-1. However, upon surface modification, the catalytic efficiency almost doubles due to the formation of Mg-AgNCs. Catalysis through AgNCs and Mg-AgNCs collectively portrays the role of the core and electrostatic surfaces. Furthermore, the role of electrostatic interaction has been substantiated by varying the ionic strength of the medium, as well as employing different molecular systems. A quantitative assessment of the Debye screening length asserts the correlation between the ionic strength of the medium and the role of electrostatic interactions involved herein. This highly enhanced catalytic aspect has been utilized for the real sample analysis, wherein AgNCs unexpectedly outperform Mg-AgNCs. This approach of real sample analysis also emanates the role of electrostatics involved. This comprehensive investigation represents the influential role of the core and ligand shell of MNCs as well as the role of electrostatics on its catalytic activities, which is relevant for the rational design of highly efficient catalysts.

Ligation of Titanium-oxide and {Mo2} Units for Solar CO2 Storage.

Two Mo-Ti-mixed oxide clusters, Ti6Mo4 and Ti4Mo4, which contain the {Mo2V} unit commonly observed in many polyoxomolybdates, were successfully synthesized. The introduction of a {Mo2V} dopant into a titanium-oxide cluster (TOC) results in a red shift of the absorption edge, hence leading to a substantial enhancement of visible-light absorption. The band gap electron transition mainly involves the ligand-to-metal charge transfer (LMCT, benzoate-to-Mo) and MoV d-d transition. Both clusters show favorable visible-light responsiveness and charge-separation efficiency. Both serve as heterogeneous photocatalysts and exhibit excellent catalytic activity in CO2/epoxide cycloadditions under very mild conditions. The mechanism study suggests that the catalytically active sites are mainly MoV, and the photogenerated electrons and holes are both involved. Ti6Mo4 exhibits better photocatalytic activity than Ti4Mo4, demonstrating the crucial role of the titanium-oxide core, which corresponds to improved light absorption and charge-separation efficiency. Our findings highlight the potential of the {Mo2V} unit in constructing Mo-Ti-mixed oxide clusters with interesting topologies and excellent solar-light-harvesting activity.

Piezoelectric, mechanical, and crystallographic properties of polyvinylidene fluoride‐hexafluoropropylene based composites reinforced by different dimensional carbon nanomaterials

AbstractPolymer based piezoelectric materials are increasingly used because of their lightweight and flexibility. To understand the effects of different dimensional carbon nanomaterials on the properties of polyvinylidene fluoride‐hexafluoropropylene (PVDF‐HFP) based composites, carbon black (CB), carbon nanotube (CNT), and few‐layer graphene (FLG) were used to reinforce PVDF‐HFP for preparing different composites, respectively. Their piezoelectric, mechanical, and crystallographic properties were tested. The results show that CB/PVDF‐HFP composite film has the best piezoelectric property, successively followed by FLG/PVDF‐HFP and CNT/PVDF‐HFP at 0.5%, 0.05%, and 0.1% contents of CB, FLG, and CNT, respectively. In the initial crystallization stage, CB better plays the best role of crystallization core, increasing the electroactive crystalline phase content and crystallization rate. The appropriate contents of CNT and FLG promote the formation of β crystalline phase. In the polarization stage, CB forms a uniform nonconductive network in the composite film and shows the best polarization effect. CNT tends to form connections and has the worst polarization effect. FLG forms a “microcapacitor” structure to enhance the local polarization effect. The effects of CB, CNT, and FLG on crystalline phase changes and piezoelectric property enhancements of PVDF‐HFP based composites are mainly due to their differences in size, morphology, and quantity.Highlights Effects of CB, CNT, and FLG on the piezoelectricity of PVDF‐HFP are investigated; CB more obviously increases the piezoelectricity of PVDF‐HFP than CNT and FLG; α, β, and γ crystalline phase changes in PVDF‐HFP based composites are understood; CB forms smaller and more uniform crystal cores in PVDF‐HFP than CNT and FLG; CB markedly increases the contents of electroactive crystalline phases in PVDF‐HFP.

About this title - Core Values: the Role of Core in Twenty-first Century Reservoir Characterization

Through state-of-the-art reviews and case studies this volume illustrates how innovative technologies, approaches and thinking continue to reinvent the value of both newly-acquired and legacy core for subsurface evaluation. Such an assessment is timely given that the sector sits at a pivotal point in terms of changing economics, demographics, skillsets and energy solutions.

The role of core in twenty-first century reservoir characterization: an introduction

Abstract The first two decades of the twenty-first century have seen significant advances across a wide range of reservoir characterization techniques, from microscale digital rock physics to macroscale 3D and 4D seismic. At the same time, industry downturns and the requirements of the energy transition have demanded improved understanding of the value and impact of subsurface data to justify their acquisition and commercial relevance. Despite changing technologies and demands, the acquisition, description and analysis of core remains a fundamental tool in managing subsurface uncertainty and associated risk. Value continues to be created in relation to the reservoir property, sedimentological, diagenetic and structural characterization of subsurface reservoirs, and these are the focus of the Core Values volume. The enduring business impact of core reflects advances in acquisition methods and laboratory-based core analysis (Theme 1 of the volume); the recent development of multi-sensor core scanning and associated artificial intelligence (AI) tools that allow unprecedented high-resolution data collection and visualization (Theme 2); the integration of core-derived data with new complementary technologies, leading to improved characterization of both cored and uncored intervals (Theme 3); the changing nature and role of legacy core collections due to digitization and improved data access (Theme 4). These are complemented by the need to better understand both existing hydrocarbon resources and other subsurface energy-related systems, particularly CCUS (carbon capture, utilization and storage), geothermal energy and the long-term storage of nuclear waste (Theme 5). Through the energy transition core will remain the ground truth foundation to any subsurface understanding and evaluation. At the same time, the technologies available to maximize the applied value of core will continue to develop and evolve, with the integration of diverse and complex core-derived and core-related datasets becoming the norm. Even in the face of AI's impact and value in handling such datasets, those earth scientists who can effectively analyse, interpret and integrate core will still be best placed to meet the subsurface challenges of the future.

The role of the metal core in the WOx inverse catalyst performance

The role of the metal core in the WOx inverse catalyst performance