Features Of Transition Research Articles

Liquid-liquid crystalline phase separation of spider silk proteins

AbstractLiquid-liquid phase separation (LLPS) of proteins can be considered an intermediate solubility regime between disperse solutions and solid fibers. While LLPS has been described for several pathogenic amyloids, recent evidence suggests that it is similarly relevant for functional amyloids. Here, we review the evidence that links spider silk proteins (spidroins) and LLPS and its role in the spinning process. Major ampullate spidroins undergo LLPS mediated by stickers and spacers in their repeat regions. During spinning, the spidroins droplets shift from liquid to crystalline states. Shear force, altered ion composition, and pH changes cause micelle-like spidroin assemblies to form an increasingly ordered liquid-crystalline phase. Interactions between polyalanine regions in the repeat regions ultimately yield the characteristic β-crystalline structure of mature dragline silk fibers. Based on these findings, we hypothesize that liquid-liquid crystalline phase separation (LLCPS) can describe the molecular and macroscopic features of the phase transitions of major ampullate spidroins during spinning and speculate whether other silk types may use a similar mechanism to convert from liquid dope to solid fiber.

Research on the evolution and driving factors of the coupling relationship among tourism industry, urbanization and human settlements of the urban agglomeration in the middle reaches of the Yangtze River.

This study examines the evolution of the coupling relationship among the tourism industry, urbanization, and human settlements of the urban agglomeration in the middle reaches of the Yangtze River from 2005 to 2019. By employing a constructed evaluation index system and a quantitative analysis model, the study aims to characterize and analyze this relationship. The key findings are as follows: (1) The coupling coordination level of the three major systems exhibits a continuous upward trend over the study period, albeit with a gradually slowing growth rate. The Changsha -Zhuzhou-Xiangtan urban agglomeration shows the highest average growth rate, followed by the Wuhan metropolitan area and the Poyang Lake urban agglomeration. (2) The variation coefficient and Taylor index of the coupling coordination degree demonstrate a fluctuating downward trend, indicating a convergence in spatial differences in interregional coupling coordination levels. Internal differences between city clusters within urban agglomerations are identified as the main source of overall differences in coupling coordination levels. (3) The coupling coordination levels of the three major systems follow an evolutionary trajectory characterized by "serious imbalance, moderate imbalance, mild imbalance". Clear features of level transitions are observed among various cities. (4) The endowment of tourism resources emerges as the primary factor driving the evolution of the coupling relationship among the tourism industry, urbanization, and human settlements. The study highlights the increasing diversification of driving forces and significant spatiotemporal heterogeneity in interregional driving forces for coupling relationship evolution factors.

Multi-perspective API call sequence behavior analysis and fusion for malware classification

The growing variety of malicious software, i.e., malware, has caused great damage and economic loss to computer systems. The API call sequence of malware reflects its dynamic behavior during execution, which is difficult to disguise. Therefore, API call sequence can serve as a robust feature for the detection and classification of malware. The statistical analysis presented in this paper reveals two distinct characteristics within the API call sequences of different malware: (1) the API existence feature caused by frequent calls to the APIs with some special functions, and (2) the API transition feature caused by frequent calls to some special API subsequence patterns. Based on these two characteristics, this paper proposes MINES, a Multi-perspective apI call sequeNce bEhavior fuSion malware classification Method. Specifically, the API existence features from different perspectives are described by two graphs that model diverse rich and complex existence relationships between APIs, and we adopt the graph contrastive learning framework to extract the consistent shared API existence feature from two graphs. Similarly, the API transition features of different hops are described by the multi-order transition probability matrices. By treat each order as a channel, a CNN-based contrastive learning framework is adopted to extract the API transition feature. Finally, the two kinds of extracted features are fused to classify malware. Experiments on five datasets demonstrate the superiority of MINES over various state-of-the-arts by a large margin.

SERPINA1 promotes the invasion, metastasis, and proliferation of pancreatic ductal adenocarcinoma via the PI3K/Akt/NF-κB pathway

Serpin peptidase inhibitor clade A member 1 (SERPINA1) is highly expressed in a variety of solid tumors. However, its role in pancreatic ductal adenocarcinoma (PDAC) remains unclear. Here, we report evidence that SERPINA1 acts as a potent oncogene to drive its extremely malignant character. We found that elevated SERPINA1 expression in primary tumors was associated with lymph node metastasis and shorter survival in PDAC patients. Mechanistic investigations revealed that overexpression of SERPINA1 induced nuclear translocation and phosphorylation of the p65 subunit through the PI3K/Akt/NF-κB pathway, thereby promoting the invasion, metastasis and proliferation of PDAC cells in vitro and in vivo. Conversely, the knockdown of SERPINA1 attenuated this signaling pathway and restored the phenotype of PDAC cells overexpressing SERPINA1. Overall, our study reveals that SERPINA1 affects the properties of PDAC through the PI3K/Akt/NF-κB pathway, and its activation confers the clinical features of epithelial-mesenchymal transition and proliferation in the disease.

Features of Transition from Digital Economy to Data Economy

Features of Transition from Digital Economy to Data Economy

Emerging Functions of Neuromodulation during Sleep.

Neuromodulators act on multiple timescales to affect neuronal activity and behavior. They function as synaptic fine-tuners and master coordinators of neuronal activity across distant brain regions and body organs. While much research on neuromodulation has focused on roles in promoting features of wakefulness and transitions between sleep and wake states, the precise dynamics and functions of neuromodulatory signaling during sleep have received less attention. This review discusses research presented at our minisymposium at the 2024 Society for Neuroscience meeting, highlighting how norepinephrine, dopamine, and acetylcholine orchestrate brain oscillatory activity, control sleep architecture and microarchitecture, regulate responsiveness to sensory stimuli, and facilitate memory consolidation. The potential of each neuromodulator to influence neuronal activity is shaped by the state of the synaptic milieu, which in turn is influenced by the organismal or systemic state. Investigating the effects of neuromodulator release across different sleep substates and synaptic environments offers unique opportunities to deepen our understanding of neuromodulation and explore the distinct computational opportunities that arise during sleep. Moreover, since alterations in neuromodulatory signaling and sleep are implicated in various neuropsychiatric disorders and because existing pharmacological treatments affect neuromodulatory signaling, gaining a deeper understanding of the less-studied aspects of neuromodulators during sleep is of high importance.

Is Transitivity Register-specific? A Corpus Exploration of Online Science News

This paper deals with parsing and exploring transitivity in ten online science news articles in one of the leading national broadsheets in the Philippines. The corpus analysis used two software applications: AntConc and UAM Corpus. Specifically, this study compared the transitivity features of ten online science news with the transitivity features of non-science-based registers. The transitivity analysis of the science-based and the non-science-based registers has resulted in identifying and classifying the underlying semantic roles of Participants, Process types, and Circumstances. Identifying the semantic features across the registers has resulted in identifying the prominent and foregrounded features of transitivity in the corpus. This study reiterates that foregrounding is crucial in stylistic analysis of texts. The analysis has established that while the non-science-based registers use the six Process types, the science-based registers primarily use the Material and the Relational Process types. This disproportionate occurrence of the Process types, especially the non-use of the Behavioral process types, strongly corroborates the notion that transitivity is register-specific. The present study supports a systemic and functional stance that considers language a network of choices applicable across varied genres and registers. Also, this study recommends the use of software applications in language pedagogy. Finally, the findings may also facilitate teaching L2 academic writing and producing science-based materials.

The Role of TGF-β1 and Mutant SMAD4 on Epithelial-Mesenchymal Transition Features in Head and Neck Squamous Cell Carcinoma Cell Lines.

The aim of the present study was to investigate possible differences in the sensitivity of HNSCC cells to known EMT regulators. Three HNSCC cell lines (UM-SCC-1, -3, -22B) and the HaCaT control keratinocyte cell line were exposed to transforming growth factor beta 1 (TGF-β1), a known EMT master regulator, and the cellular response was evaluated by real-time cell analysis (RTCA), Western blot, quantitative PCR, flow cytometry, immunocytochemistry, and the wound closure (scratch) assay. Targeted sequencing on 50 cancer-related genes was performed using the Cancer Hotspot Panel v2. Mutant, and wild type SMAD4 cDNA was used to generate recombinant SMAD4 constructs for expression in mammalian cell lines. The most extensive response to TGF-β1, such as cell growth and migration, β-actin expression, or E-cadherin (CDH1) downregulation, was seen in cells with a more epithelial phenotype. Lower response correlated with higher basal p-TGFβ RII (Tyr424) levels, pointing to a possible autocrine pre-activation of these cell lines. Targeted sequencing revealed a homozygous SMAD4 mutation in the UM-SCC-22B cell line. Furthermore, PCR cloning of SMAD4 cDNA from the same cell line revealed an additional SMAD4 transcript with a 14 bp insertion mutation, which gives rise to a truncated SMAD4 protein. Overexpression of this mutant SMAD4 protein in the highly epithelial control cell line HaCaT resulted in upregulation of TGF-β1 and vimentin. Consistent with previous reports, the invasive and metastatic potential of HNSCC tumor cells appears associated with the level of autocrine secretion of EMT regulators such as TGF-β1, and it could be influenced by exogenous EMT cytokines such as those derived from immune cells of the tumor microenvironment. Furthermore, mutant SMAD4 appears to be a significant contributor to the mesenchymal transformation of HNSCC cells.

Exploring land system reform for demographic transition in rural China

Rural population in China has undergone dramatic changes driven by large-scale industrialization and urbanization. However, under the current land system, it is difficult to adjust rural land resource allocation according to population changes, resulting in an imbalance in the human-land relationship of rural China and restricting the sustainable development of agriculture and rural areas. Therefore, there is an urgent need to further promote land system reform to cope with rural demographic transition and the challenges it brings to rural human-land relationship and provide institutional support for rural revitalization in the new era. The results show that population contraction, population aging, and below-replacement fertility are the main features of China's rural population transition in 1990–2020, which brings about problems such as the aging and weaking of social actors and non-grain farming. Meanwhile, the disconnect between land-use transition and demographic transition determines that inefficient land use, mainly characterized by cropland abandonment and homestead idle, is prevalent in rural China. Focusing on the trend of demographic transition in rural China, deepening the reform of contracted land, steadily advancing the reform of homesteads, and strengthening the provision of supporting policies are needed. These measures aim to promote the capitalization and assetization of land resources through the introduction of market mechanisms and empowerment, thus enhancing land resource allocation efficiency and optimizing rural human-land relationship.

Impact of Natural Disasters on Mental Health: Evidence and Implications.

Natural disasters are large-scale catastrophic events, and they are increasing in frequency and severity. Converging evidence indicates that the mental health consequences of disasters are extensive and are often associated with trauma and the disruption of personal and socioeconomic factors in people's lives. Although most individuals experiencing disaster-related traumatic events do not develop mental illnesses, some experience adverse psychological effects of disasters. These mental health effects begin immediately following a disaster and may persist for extended periods. In this article, we summarize the literature findings to provide a narrative review that focuses on the mental health consequences of natural disasters. An overview of the disaster mental health research field is provided, and the findings are ordered into theoretical frameworks. Then, the development and course of psychopathology regarding disaster aftermath are described in a methodological context. Next, understanding a disaster as an event of transition is highlighted, and the impact of this disaster-specific transition is discussed. Lastly, a potential relationship between the transitional impact of a disaster and mental health consequences is speculated on, and the implications are discussed. The impact of disasters on mental health can be direct or indirect, short-term or long-term, and to some extent depends on the recovery process of the affected community. Also, we propose the possible merits of using the Transitional Impact Scale in the context of disaster mental health research by assessing the features of disaster-related transition and its effects on mental health. We conclude by suggesting a direction for future research in terms of measuring the disaster mental health effects in community settings (affected vs. non-affected) and also considering cross-cultural and cross-regional differences. In recent decades, a large amount of knowledge has been gathered from disaster mental health research, but, still, more research is needed to resolve some irregular findings through refining the methodological variations.

Evaluating the associations between dysautonomia, gastrointestinal transit, and clinical phenotype in patients with systemic sclerosis.

Our objective was to identify systemic sclerosis (SSc) patients with a high burden of autonomic symptoms and to determine whether they have a distinct clinical phenotype, gastrointestinal (GI) transit or extraintestinal features. In a prospective cohort of SSc patients with GI disease, clinical data were systematically obtained at routine visits. Dysautonomia was identified by the Composite Autonomic Symptom Score (COMPASS)-31questionnaire. GI transit was measured by whole-gut scintigraphy. Associations between total COMPASS-31 scores and clinical features, GI symptoms, and transit were evaluated. Comparisons between patients with global autonomic dysfunction [(GAD); ≥5 positive COMPASS-31 subdomains] and those with limited autonomic dysfunction [(LAD); <5 positive subdomains] were also studied. 91 patients with SSc and GI involvement were included [mean age 57, 90% female, 74% limited cutaneous disease, 83% significant GI disease (Medsger score ≥2)]. The mean COMPASS-31 score in SSc was higher than controls (38.8 vs. 7.2). 33% had GAD, 67% had LAD. Patients with GAD were more likely to have limited SSc (93% vs. 65%; p<0.01) and have sicca symptoms (100% vs. 77%; p=0.01). Gastric and colonic transit were faster in patients with GAD (p<0.05). Upper GI involvement (Medsger GI score of 1 or 2) was associated with higher total COMPASS-31 scores (p=0.02). Symptoms of global dysautonomia are seen in up to one-third of patients with SSc and GI involvement. Identifying specific clinical characteristics associated with GAD in SSc will help to identify a population that may benefit from therapies that modulate the autonomic nervous system.

1958P Influence of androgen deprivation therapy (ADT) on epithelial-mesenchymal transition (EMT) and cancer stem cell (CSC) features in prostate cancer (PCa)

1958P Influence of androgen deprivation therapy (ADT) on epithelial-mesenchymal transition (EMT) and cancer stem cell (CSC) features in prostate cancer (PCa)

Advantages of Ultrathin AlN/GaN/AlN Quantum Wells for Excitonic Population Distribution and Transition Features Studied by Phononic–Excitonic–Radiative Model

Excitons are expected to be a high‐efficiency emission source in UV light‐emitting devices. However, the damping of the excitonic laser oscillation has been reported under conditions where the excitonic states are expected to be populated in the conventional theory. In order to understand the exciton dynamics under the thermal nonequilibrium state, a theoretical model including various energy species in semiconductors such as electrons, phonons, and photons is required. Herein, a 2D phononic–excitonic–radiative model is constructed to analyze the exciton dynamics in a 2D system. 2D excitons with four principal quantum number states and the continuum in the lowest energy level of the AlN/GaN/AlN quantum wells are considered. It is found that the 2D phonon significantly augments the excitation transition rate. When the high recombination rate corresponding to stimulated emission is considered, the exciton binding energy of 108 meV is not enough to reduce the population in the high‐order discreet states and the continuum states, while the binding energy of 215 meV corresponding to the one monolayer GaN has an advantage of reducing these populations. The analysis of population flux has an advantage in discussing the increase in the kinetic energy transfer to the 1S exciton.

Characterization of two melanoma cell lines resistant to BRAF/MEK inhibitors (vemurafenib and cobimetinib)

BackgroundBRAF (v-raf murine sarcoma viral oncogene homolog B1)/MEK (mitogen-activated protein kinase kinase) inhibitors are used for melanoma treatment. Unfortunately, patients treated with this combined therapy develop resistance to treatment quite quickly, but the mechanisms underlying this phenomenon are not yet fully understood. Here, we report and characterize two melanoma cell lines (WM9 and Hs294T) resistant to BRAF (vemurafenib) and MEK (cobimetinib) inhibitors.MethodsCell viability was assessed via the XTT test. The level of selected proteins as well as activation of signaling pathways were evaluated using Western blotting. The expression of the chosen genes was assessed by RT-PCR. The distribution of cell cycle phases was analyzed by flow cytometry, and confocal microscopy was used to take photos of spheroids. The composition of cytokines secreted by cells was determined using a human cytokine array.ResultsThe resistant cells had increased survival and activation of ERK kinase in the presence of BRAF/MEK inhibitors. The IC50 values for these cells were over 1000 times higher than for controls. Resistant cells also exhibited elevated activation of AKT, p38, and JNK signaling pathways with increased expression of EGFR, ErbB2, MET, and PDGFRβ receptors as well as reduced expression of ErbB3 receptor. Furthermore, these cells demonstrated increased expression of genes encoding proteins involved in drug transport and metabolism. Resistant cells also exhibited features of epithelial-mesenchymal transition and cancer stem cells as well as reduced proliferation rate and elevated cytokine secretion.ConclusionsIn summary, this work describes BRAF/MEK-inhibitor-resistant melanoma cells, allowing for better understanding the underlying mechanisms of resistance. The results may thus contribute to the development of new, more effective therapeutic strategies.

Structural, magnetic, and luminescent properties of NaGdF4:Nd3+@Fe3O4 nanocomposites

The diverse applications of nanomaterials, and their rapidly increasing demand, have spurred the development of novel multifunctional materials. As such, this study aimed to synthesize and characterize a magneto-luminescent nanocomposite, composed of magnetite and fluorescent quantum dots (NaGdF4:Nd3+@Fe3O4). Nanomaterial synthesis was accomplished through solvothermal and co-precipitation methods. Stable nanoparticles (NPs) with a zeta potential of -19.57 ± 0.42 mV, and a size of 4.55 ± 1.44 nm were obtained. The crystalline structure of the NPs, verified via x-ray diffraction, affirmed the hexagonal pattern of the NaGdF4:Nd3+NPs and the inverse spinel pattern of Fe3O4NPs. In the diffraction pattern of the NaGdF4:Nd3+@Fe3O4NPs, only the phase pertaining to the Fe3O4NPs was identified, indicating their influence on the nanocomposite. Magnetic measurements revealed the superparamagnetic behavior of the material. Photoluminescence spectra of NaGdF4:Nd3+and NaGdF4:Nd3+@Fe3O4NPs verified the luminescent emission around 1060 nm; a feature of the radiative transitions of Nd3+ions. Based on the assessed characteristics, the nanocomposite's multifunctionality was confirmed, positioning the material for potential use in various fields, such as biomedicine.

Real-Space Imaging of Intrinsic Symmetry-Breaking Spin Textures in a Kagome Lattice.

The electronic orders in kagome materials have emerged as a fertile platform for studying exotic quantum states, and their intertwining with the unique kagome lattice geometry remains elusive. While various unconventional charge orders with broken symmetry is observed, the influence of kagome symmetry on magnetic order has so far not been directly observed. Here, using a high-resolution magnetic force microscopy, it is, for the first time, observed a new lattice form of noncollinear spin textures in the kagome ferromagnet in zero magnetic field. Under the influence of the sixfold rotational symmetry of the kagome lattice, the spin textures are hexagonal in shape and can further form a honeycomb lattice structure. Subsequent thermal cycling measurements reveal that these spin textures transform into a non-uniform in-plane ferromagnetic ground state at low temperatures and can fully rebuild at elevated temperatures, showing a strong second-order phase transition feature. Moreover, some out-of-plane magnetic moments persist at low temperatures, supporting the Kane-Mele scenario in explaining the emergence of the Dirac gap. The observations establish that the electronic properties, including both charge and spin orders, are strongly coupled with the kagome lattices.

Magnetic properties and large low-field magnetocaloric effect of RFe2Si2 (R = Ho, Tm) compounds

Nowadays, magnetic refrigerant technology has drawn much attention for its environmental friendliness. Those magnetic materials possessing giant low-field magnetocaloric effect (MCE) performance are of great importance for practical applications, especially at low temperatures. Herein, we present a detailed study on polycrystalline magnetocaloric compounds HoFe2Si2 and TmFe2Si2. HoFe2Si2 exhibits a transition from antiferromagnetic to paramagnetic phase at 2.2 K, while no long-range magnetic ordering is observed in TmFe2Si2 even temperature down to 2 K. For both compounds, they showed large low-field magnetic entropy change (−ΔSM) with the peak values of 10.6 and 7.9 J kg−1 K−1 under field change of 0–2 T for HoFe2Si2 and TmFe2Si2, respectively, which is comparable or even larger than some low-temperature magnetocaloric materials. In addition, the characteristic of second-order magnetic transitions of both compounds were confirmed on basis of Arrott plots and mean-field theory criterion. The low magnetic ordering temperatures, large low-field MCE performance along with the feature of second order phase transition for HoFe2Si2 and TmFe2Si2 indicate that both compounds are promising candidate for magnetic refrigerant materials at liquid helium temperature.

Revealing failure law of single-track traffic-loaded concrete airport pavement from a thermodynamic perspective

ABSTRACT With the growth of global air traffic and the popularity of large aircraft, the design and life prediction of airport pavements have received increasing attention from scholars. However, concrete airport pavement evaluations based on cracking patterns are often uncertain. A thermodynamic-based failure analysis of the FAA Phase 4 Construction Cycle 8 (CC8) strength and fatigue traffic test is conducted in this work to investigate the failure laws of airport concrete pavements. First, this work equates concrete pavement failure to a phase transition. It converts strain data from full-scale traffic tests into state variables. Based on the Wilson theory definition of phase transition, network-free renormalisation is applied to reveal the concrete slab stressing state evolution and phase transition features. The clustering algorithm that utilises the attractor effect of phase transition points determines characteristic points. In summary, this work applies network-free renormalisation and clustering algorithms to reveal robust concrete pavement failure points, which can provide a reference for airport pavement design, assessment, and failure warning. Furthermore, this work further validates the stressing state theory and network-free renormalisation under high-speed time-varying conditions.

Generalization of interfacial thermal conductance based on interfacial phonon localization

Interfacial energy transport is of great engineering and scientific importance. Traditional theoretical treatment based on phonon reflection and transmission only provides qualitative understanding of the interfacial thermal conductance (G). In the interface region, the material has gradual (covalent) or abrupt (van de Waals) physical structure transition, each transition features interface-region atomic interactions that are different from those of both adjoining sides. This difference makes the interface-region phonons extremely localized. Here, by constructing an “equivalent interfacial medium” (EIM) that accounts for the extremely localized phonon region, G can be described by a universal physical model that is characterized by an “interface characteristic temperature” (Θint) and energy carrier transfer time. The EIM model fits widely reported G ∼ T (T: temperature) data with high accuracy and provides remarkable prediction of G at different temperatures based on 2–3 experimental data points. Under normalized temperature (T/Θint) and interfacial thermal conductance (G/Gmax), all literature data of G can be universally grouped to a single curve. The EIM model provides a solid correlation between G and interfacial structure and is expected to significantly advance the physical understanding and design of interfacial energy transport toward high-efficiency energy conversion, transport, and micro/nanoelectronics.

Modified Re‐Entrant‐Like (K, Na)NbO3‐Based Relaxors with Superior Electrostrain Properties

AbstractPiezoceramics with large strain output, low hysteresis, and wide operation temperature are indispensable for the high‐end displacement control. Unfortunately, requiring these merits simultaneously remains a long‐standing challenge for lead‐free piezoceramics promising for replacing lead‐based ones. Herein a new strategy to resolve this challenge by developing modified re‐entrant‐like potassium sodium niobate ((K, Na)NbO3, KNN) relaxors is presented. Multi‐scale structural analysis reveals the presence of the significant local disorder, nano‐sized multi‐phase coexistence, and ultra‐fine grains, which facilitate the polarization rotation, effectively eliminate non‐180° domains, and erase polymorphic phase transition features in re‐entrant‐like KNN relaxors. Consequently, a combination of large strain (≈0.19%), ultra‐low hysteresis (&lt;7%), high electrostriction coefficient (Q33 = 0.049 m4 C−2), and benign temperature stability (i.e., strain varies less than 10.6% within 30–120 °C) is realized, superior to other lead‐free relaxors. Therefore, this strategy provides a novel paradigm for designing high‐performance lead‐free piezoceramics used for high‐precision actuators.