Types Of Transitions Research Articles

Optical and microscopic characterizations of polyethylene oxides (PEO) doped with nickel nitrate (NiNO₃) transition metal salt

This study used a solution cast process to prepare a PEO doped with (4, 8 and 12 wt%) NiNO3 metal salt. Techniques including FTIR, optical microscope (OM), and UV–Visible-absorption spectrometry were employed to examine the structural, microscopic configuration and optical behaviors of the electrolyte. The FTIR bands indicated shifting and narrowing of PEO-O-H stretching bands by addition of 4w%NiNO3, suggesting a good interaction between the NiNO3 and the polymer. The optical microscope images showed the dark regions ascribed to amorphous phases and it is more dominant in the doped films than in the pure films. According to the optical absorption measurements optimum absorption and transmission of UV–visible light were observed at 4 wt% filler loading. Absorbance and transmittance of PEO were amplified by integrating 4 wt%NiNO3, although concentration above 4 wt% had insignificant influence on the optical behavior of PEO. The PEO:4w% NiNO3 films showed a higher value of refractive index and a greater optical conductivity in the UV wavelength which confirmed the presence of more charge carriers in the doped film. The regions attributed to band gap width and the different types of electron transitions were identified by using the Tauc's model in detail. The absorption edge shifting was distinguished for the 4 wt% doped PEO, and the optical band gap was reduced from 5.25 eV to 4.2 eV.

Photoluminescent investigation of Ba2LaV3O11:Dy3+ nanophosphors with cool white light emission for near-UV based WLEDs

Dy3+ doped Ba2LaV3O11 nanophosphor is one of the most promising energy converters for solid-state lighting (SSL) as it has outstanding potential to absorb near-ultraviolet light along with brilliant luminous features. Ba2LaV3O11 nanophosphors doped with varied compositions of Dy3+ ions are successfully prepared through an energy-efficient urea-based solution combustion production route. Benefitting from its facile synthesis route at low cost, longer operational lifetime the prepared nanophosphors may be used as luminescent material for WLEDs. Recently, modern white light-emitting diodes (WLEDs) have been fabricated based on the energy-conversion via efficient phosphor material. The current report is about the realization of white light emanation through doping a single dopant ion in vanadate host lattice. The outcomes evidence that the optimum Ba2La0.97Dy0.03V3O11 nanophosphor exhibits excellent performance in WLEDs. The diffuse reflectance spectrum (DRS) measured for the optimum nanopowder sample is subjected to Tauc's plot analysis, revealing a higher optical band-gap of 3.69 eV. The typical photoluminescence emission transitions of Dy3+ ions noticed in wavelength ranging from 400 nm to 650 nm are owing to intra 4f shifts upon excitation via 352 nm wavelength. In last, photometric characterizations are carried out disposing the outstanding result of color chromaticity coordinates as well as correlated color temperature (CCT) value.

Single-cell transcriptomic analysis of gingivo-buccal oral cancer reveals two dominant cellular programs.

Oral squamous cell carcinoma of the gingivo-buccal region (OSCC-GB) is the most common cancer among men in India, and is associated with poor prognosis and frequent recurrence. Cellular heterogeneity in OSCC-GB was investigated by single-cell RNA sequencing of tumors derived from the oral cavity of 12 OSCC-GB patients, 3 of whom had concomitant presence of a precancerous lesion (oral submucous fibrosis [OSMF]). Unique malignant cell types, features, and phenotypic shifts in the stromal cell population were identified in oral tumors with associated submucous fibrosis. Expression levels of FOS, ATP1A, and DUSP1 provided robust discrimination between tumors with or without the concomitant presence of OSMF. Malignant cell populations shared between tumors with and without OSMF were enriched with the expression of partial epithelial-mesenchymal transition (pEMT) or fetal cell type signatures indicative of two dominant cellular programs in OSCC-GB-pEMT and fetal cellular reprogramming. Malignant cells exhibiting fetal cellular and pEMT programs were enriched with the expression of immune-related pathway genes known to be involved in antitumor immune response. In the tumor microenvironment, higher infiltration of immune cells than the stromal cells was observed. The T cell population was large in tumors and diverse subtypes of T cells with varying levels of infiltration were found. We also detected double-negative PLCG2+ T cells and cells with intermediate M1-M2 macrophage polarization. Our findings shed light on unique aspects of cellular heterogeneity and cell states in OSCC-GB.

Turning catalytically active pores into active pumps.

We develop a semi-analytical model of self-diffusioosmotic transport in active pores, which includes advective transport and the inverse chemical reaction that consumes solute. In previous work [Antunes et al., Phys. Rev. Lett. 129, 188003 (2022)], we have demonstrated the existence of a spontaneous symmetry breaking in fore-aft symmetric pores that enables them to function as a micropump. We now show that this pumping transition is controlled by three timescales. Two timescales characterize advective and diffusive transport. The third timescale corresponds to how long a solute molecule resides in the pore before being consumed. Introducing asymmetry to the pore (either via the shape or the catalytic coating) reveals a second type of advection-enabled transition. In asymmetric pores, the flow rate exhibits discontinuous jumps and hysteresis loops upon tuning the parameters that control the asymmetry. This work demonstrates the interconnected roles of shape and catalytic patterning in the dynamics of active pores and shows how to design a pump for optimum performance.

Identifying the type of transition experienced by newly qualified physics teachers entering the workplace

ABSTRACT This study examines teachers’ experiences of transition at different points in time over a two-year period to encapsulate their journey to becoming a qualified teacher. Six novice teachers participated in a study in their final year of university through to their first year as a newly qualified teacher. Reflective journals, one-to-one interviews and qualitative surveys formed that database for reflexive thematic analysis and theme maps. Schlossberg’s indicators for identifying transition were then related to the analysed data to establish the type of transition experienced by teachers. Findings from the study shed light on the overlapping nature of transitions experienced by novice teachers and highlight opportunities for professional learning to aid for the smoothening of these transitions for aspiring teachers.

Dynamics of cascades in spatial interdependent networks.

The dynamics of cascading failures in spatial interdependent networks significantly depends on the interaction range of dependency couplings between layers. In particular, for an increasing range of dependency couplings, different types of phase transition accompanied by various cascade kinetics can be observed, including mixed-order transition characterized by critical branching phenomena, first-order transition with nucleation cascades, and continuous second-order transition with weak cascades. We also describe the dynamics of cascades at the mutual mixed-order resistive transition in interdependent superconductors and show its similarity to that of percolation of interdependent abstract networks. Finally, we lay out our perspectives for the experimental observation of these phenomena, their phase diagrams, and the underlying kinetics, in the context of physical interdependent networks. Our studies of interdependent networks shed light on the possible mechanisms of three known types of phase transitions, second order, first order, and mixed order as well as predicting a novel fourth type where a microscopic intervention will yield a macroscopic phase transition.

Single-cell RNA sequencing analysis reveals transcriptional heterogeneity of multiple primary lung cancer.

With the advancements in early diagnosis, more and more patients with multiple primary lung cancer (MPLC) have been identified. However, the progression of MPLC involves complex changes in cell composition and metabolic function, which remains largely controversial. Our study aims to comprehensively reveal the cellular characteristics and inter-cellular connections of MPLC. We performed scRNA-seq from 23 samples of six MPLC patients, combined with bulk whole-exome sequencing. We performed trajectory analysis to investigate the transition of different cell types during the development of MPLC. A total of 167397 cells were sequenced derived from tumour and adjacent tissues of MPLC patients, and tumour, normal, immune and stromal cells were identified. Two states of epithelial cells were identified, which were associated with immune response and cell death, respectively. Furthermore, both CD8+ naïve and memory T cells participated in the differentiation of CD8+ T cells. The terminal states of CD8+ T cells were exhausted T cells and cytotoxic T cells, which positively regulated cell death and were implicated in the regulation of cytokine production, respectively. Two main subpopulations of B cells with distinct functions were identified, which participate in the regulation of the immune response and antigen presentation, respectively. In addition, we found a specific type of endothelial cells that were abundant in tumour samples, with an increasing trend from normal to tumour samples. Our study showed the comprehensive landscape of different cells of MPLC, which might reveal the key cellular mechanisms and, therefore, may provide new insights into the early diagnosis and treatment of MPLC.

ANALYSIS OF THE "GURI I PLAKËS" AREA AS AN OPPORTUNITY FOR THE DEVELOPMENT OF RECREATION, TOURISM AND ECONOMY, REPUBLIC OF KOSOVO

Space has an essential character for human life and activity. The reduction of touristic, recreational, sports spaces, etc., are affecting the quality of life and the health of the community in many urban areas of our country. Natural, hereditary values, etc., are of great importance for present and future generations, as a living environment for tourism and, physical and mental recreation. Tourism as an economic activity aims at the economic utilization and maximization of the natural and artificial values that a certain area, region or country has. This paper aims, based on the research results, to bring to every reader authentic data and information that show what it offers and what are the possibilities to form a tourist, recreational and sports center in the "Guri i Plakës" area, after considering the economic benefits that can be generated from this area. The work materials were: notebooks for keeping notes from the field work, handheld GPS for measuring coordinates where necessary, meter tape also for measurements, cameras, topographical maps at scale 1:50 000, geological and hydrogeological map (1:200 000), etc. The "Guri i Plakës" - in (eng: Old Woman's Stone) study area has an area of 125.08 hectares. 104.98 ha or 83.93% belong to the Municipality of Drenas (Gllogoc), while 20.10 ha or 16.07% belong to the Municipality of Obiliq. The research work identified two groups of values which make this area interesting for the development of tourism and recreation and are: natural and artificial values. The natural values include: the Drenica river the Dobroshec water source, the "Guri i Plakës", the Dora Stone (Guri Dora), the Folds in the Paleozoic formations, the karst relief in the limestone rocks. The Drenica River represents the main watershed in the "Guri i Plakës" research area. Relatively rich in aquatic flora and fauna. The study area is located in the central part of Kosovo, between coordinates 42° 40ꞌ 20ꞌꞌ N, 20° 56ꞌ 40ꞌꞌ E and belongs to the territory of Municipality of Drenas (Gllogoc) and Kastriot (Obiliq). It has an area of 125.08 hectares, with hilly mountainous relief with an altitude of up to 712 m. Important natural and artificial values have been distinguished in the study area. The proposed area "Guri i Plakës" has a physical and geographical position quite favorable for the development of a center (mini-center) for the development of tourism and recreation. Tourist activities (transit type or type of tourism) can be developed there, including activities such as: walking, camping, fishing, partly cycling, photography, recording video clips, part of the activities related to traditional nutrition (traditional food). The "Guri i Plakës" area can be used as a miniature laboratory because it contains many educational, research, scientific research components, etc. Lastly, the development of this area brings social, economic, etc. benefits for the entire community in its vicinity and other local and international visitors.

Antimicrobial activities and theoretical studies on the weak interactions formation in two different configuration complexes

The ligand 2-(3-pyrazolyl)-4-methyl-1,2-dihydroquinazoline-N3-oxide (L) was synthesized, and two transition metal complexes, namely [Cu(L)2]·(NO3)2 (1) and [Ni(L)3]·(NO3)2·3CH3OH (2) were prepared through complexation reaction between L and the corresponding metal salt. L and both complexes were characterized by elemental analysis, as well as compared with spectrographic technique for example FT-IR and UV–Vis spectroscopy. X-ray single-crystal diffraction demonstrated that 1 was tetra-coordinated square planar whereas 2 was hexa-coordinated slightly distorted octahedral geometry. Meanwhile, the metal-ligand ratios were 2:1 in 1 whereas 3:1 in 2. Through the superposition of hydrogen bonds and other weak interactions, both complexes formed 1-D chain-like, 2-D layered, and 3-D supramolecular structures. Theoretical investigations explained the optimized geometries of complexes and the electrostatic potential distribution in molecules, and also analyzed the electron transition types of L and both complexes in combination with UV–vis spectroscopy, which provided theoretical support for the experimental conclusions. Electrostatic potential (ESP) was computed for both complexes to predict the reaction positions of electrophilic and nucleophilic assaults. Hirshfeld Surface Analysis quantified interactions in molecules and analyzed the contribution of various weak interactions to stabilize the structure of complexes. Especially, antibacterial experiments displayed compounds had certain antibacterial activities against both Gram-positive and Gram-negative bacterial strains.

Phase transitions driven by magnetoelectric and interfacial Dzyaloshinskii-Moriya interaction

In this paper, we study phase transitions in a magnetoelectric bilayer with two order parameters using Monte Carlo simulation. We investigate the effects of temperature, magnetoelectric coupling, and anisotropy in the multiferroic bilayer formed by a frustrated antiferromagnetic layer with Heisenberg spins and a triangular lattice ferroelectric layer. We show that magnetic frustration induces creation of skyrmions and a skyrmion lattice at moderate values of Dzyaloshinskii-Moriya interaction and interface magnetoelectric coupling with adjacent ferroelectric layer. The skyrmion crystal is stable up to relatively high temperatures. The effect of anisotropy is to cause only a shift of the critical temperature without changing the type of the phase transition. The phase of the skyrmion lattice becomes more resistant and stable to temperature fluctuations in the case of a highly anisotropic frustrated film.

“We have to save him”: a qualitative study on care transition decisions in Ontario’s long-term care settings during the COVID-19 pandemic

BackgroundThe COVID-19 pandemic has contributed to a global crisis in long-term care (LTC) with devastating consequences for residents, families and health professionals. In Ontario, Canada the severity of this crisis has prompted some care partners to move residents home with them for the duration or a portion of the pandemic. This type of care transition, from LTC to home care, was highly unusual pre-pandemic and arguably suboptimal for adults with complex needs. This paper presents the findings of a qualitative study to better understand how residents, care partners, and health professionals made care transition decisions in Ontario’s LTC settings during the pandemic.MethodsSemi-structured interviews were conducted with 32 residents, care partners and health professionals who considered, supported or pursued a care transition in a LTC setting in Ontario during the pandemic. Crisis Decision Theory was used to structure the analysis.ResultsThe results highlighted significant individual and group differences in how participants assessed the severity of the crisis and evaluated response options. Key factors that had an impact on decision trajectories included the individuals’ emotional responses to the pandemic, personal identities and available resources.ConclusionsThe findings from this study offer novel important insights regarding how individuals and groups perceive and respond to crisis events.

Niche overlap and Hopfield-like interactions in generalized random Lotka-Volterra systems.

We study communities emerging from generalized random Lotka-Volterra dynamics with a large number of species with interactions determined by the degree of niche overlap. Each species is endowed with a number of traits, and competition between pairs of species increases with their similarity in trait space. This leads to a model with random Hopfield-like interactions. We use tools from the theory of disordered systems, notably dynamic mean-field theory, to characterize the statistics of the resulting communities at stable fixed points and determine analytically when stability breaks down. Two distinct types of transition are identified in this way, both marked by diverging abundances but differing in the behavior of the integrated response function. At fixed points only a fraction of the initial pool of species survives. We numerically study the eigenvalue spectra of the interaction matrix between extant species. We find evidence that the two types of dynamical transition are, respectively, associated with the bulk spectrum or an outlier eigenvalue crossing into the right half of the complex plane.

The Influence of Texture Type and Grain Milling Degree on the Attenuation Limit, Protein Content, and Degradation in Wheat Wort

Wheat of medium hardness with marbled endosperm (transitional form between hard and soft wheat) in which glassy and floury zones alternate, form almost exclusively available assortment for brewing needs in Southeastern Europe. The aim of this work is to establish the influence of the grain texture and the degree of milling on the attenuation limit of wheat wort obtained from this type of wheat. Wheat worts using hard, soft transitional, or marbled endosperm texture were produced. The indicators of proteolysis, cytolysis, and amylolysis were determined, with regard to the parameter attenuation limit (AL) or fermentability. From the results for the tested parameters, it was established that despite similar starting values for the most important quality parameters, transitional wheat produces significantly different wort, both among themselves and in comparison with hard and soft wheat, and also when looking at the results for different milling degree (fine or coarse). The obtained values for the attenuation limit for transition wheat are similar or even better when compared to soft wheat, with satisfactory values for almost all examined quality parameters of wort. It can be concluded that a transitional type of wheat can be used just as well as unmalted raw material for the production of wort, as well as a raw material for malting.

China’s Transition to Collective Labor Relations: Top-Down and Bottom-Up Mechanisms

Abstract The article analyzes the development, characteristics, and tendency of China’s labor relations and the labor movement in recent years. It points out that China has begun the transition from individual labor relations to collective labor relations with the strike wave in the summer of 2010 as the main turning point. In the process of transformation, there are two kinds of forces and two ways to accomplish the labor movement. One is the top-down labor union movement led by the authorities within the system; the other is the bottom-up labor movement formed spontaneously by workers outside the system. The article particularly analyzes the emergence of, and mutual relationship between these two types of transition, as well as their influence and significance on China’s labor relations.

Neodymium based acylpyrazolone complexes: Synthesis and physicochemical characterizations

The electronic spectra of three neodymium acylpyrazolone complexes with the compositions [Nd(DMBPMP)3(H2O)(EtOH)] (Nd1), [Nd(DMMCPMP)3(H2O)(EtOH)] (Nd2), and [Nd(DMBPTMP)3(H2O)(EtOH)] (Nd3) have been analyzed. Utilizing ESI-mass, FT-IR, thermogravimetric, and single crystal X-ray diffraction methods, the structure of the DMBPTMP ligand and all three complexes were investigated. According to the single crystal analysis of Nd2, the complex is mononuclear and eight-coordinate (NdO8) with a distorted square antiprismatic geometry. A powder XRD pattern confirmed a similar structural arrangement of the other two complexes. The transition 4G5/2 ← 4I9/2, which is close to the centre of the visible spectrum (∼17,500 cm−1), exhibits hypersensitivity, which stands out in stark contrast to the behaviour of many other typically weak and reliably unchanging, typical 4f-4f transitions. Through a comparative analysis of calculated oscillator strength, Judd-Ofelt parameters, and covalency parameters in various solvents, hypersensitivity, symmetry characteristics, and covalency have been thoroughly investigated. The promotion of 4f-4f electric-dipole intensity has been found to be particularly successful with DMF, DMSO, pyridine and ethanol. Utilizing Judd-Ofelt parameter Ω4 values and Hirshfeld analysis, long-range secondary π⋯π stacking or H-bonding interactions were investigated. Using solid-state emission spectra, intensity of emission spectra and antenna effect energy diagram was examined.

Route to mixed-mode oscillations via step-shaped sharp transition of equilibria in a nonlinear gyroscope oscillator

Sharp transitions in relation to the variation of system parameters are frequently encountered in many multiple-timescale systems, and they have been found to be an important factor related to the generation of mixed-mode oscillations (MMOs). The present paper aims to report a novel type of sharp transition, referred to as step-shaped sharp transition, in a nonlinear gyroscope oscillator with multiple-frequency excitations, and investigate the resulting MMOs. We show that step-shaped sharp quantitative changes in relation to the variation of system parameters can be observed in the equilibrium branch, which yields the step-shaped sharp transition. In particular, with the increase of the frequency ratio between the parametric and external excitations, more step-shaped sharp transitions appear in the equilibrium branches, which evolve into the ones displaying different structures. Based on this, the rectangular-pulse-shaped explosion of equilibria is created. Furthermore, these sharp transitions can form active areas for the MMOs, leading to the alternations between large-amplitude and small-amplitude oscillations, and finally the route to MMOs is created. Our findings have significant implications for understanding the fast-slow dynamics of the nonlinear gyroscope oscillator, contributing to the exploration of new routes to MMOs. Thus, the results could provide theoretical support for the potential application of gyroscopes.

Effect of the Textures and Particle Sizes of Limestone on the Quicklime Reaction Activity

Quicklime is not only an important raw material for the steel and nano-calcium carbonate industries but also a key carrier for capturing carbon dioxide in the fight against global warming, and its reaction activity plays a vital role in these processes. Recent studies have found that quicklime produced from limestones with similar chemical compositions under the same production process has significantly different reaction activities, which indicates that something other than the chemical composition of limestone affects quicklime reaction activity. To explore the factors affecting quicklime reaction activity, this study analyzed the textures and calcite particle size of limestone collected from different areas of Guangxi, China, and measures the quicklime reaction activity with different calcination times. It has been found that: (1) limestone with a clastic texture is preferred to that with a crystalline texture (including transition type) in yielding quicklime with higher reaction activity; and (2) for limestone with a clastic texture, fine-grained limestone tends to produce the same or higher quicklime reaction activity with lower energy consumption.

SPP1/osteopontin: a driver of fibrosis and inflammation in degenerative ascending aortic aneurysm?

Degenerative ascending aortic aneurysm (AscAA) is a silent and potentially fatal disease characterized by excessive vascular inflammation and fibrosis. We aimed to characterize the cellular and molecular signature for the fibrotic type of endothelial mesenchymal transition (EndMT) that has previously been described in degenerative AscAA. Patients undergoing elective open-heart surgery for AscAA and/or aortic valve repair were recruited. Gene expression in the intima-media of the ascending aorta was measured in 22 patients with non-dilated and 24 with dilated aortas, and candidate genes were identified. Protein expression was assessed using immunohistochemistry. Interacting distal gene enhancer regions were identified using targeted chromosome conformation capture (HiCap) in untreated and LPS-treated THP1 cells, and the associated transcription factors were analyzed. Differential expression analysis identified SPP1 (osteopontin) as a key gene in the signature of fibrotic EndMT in patients with degenerative AscAA. The aortic intima-media expression of SPP1 correlated with the expression of inflammatory markers, the level of macrophage infiltration, and the aortic diameter. HiCap analysis, followed by transcription factor binding analysis, identified ETS1 as a potential regulator of SPP1 expression under inflammatory conditions. In conclusion, the present findings suggest that SPP1 may be involved in the development of the degenerative type of AscAA. KEY MESSAGES: In the original manuscript titled "SPP1/osteopontin, a driver of fibrosis and inflammation in degenerative ascending aortic aneurysm?" by David Freiholtz, Otto Bergman, Saliendra Pradhananga, Karin Lång, Flore-Anne Poujade, Carl Granath, Christian Olsson, Anders Franco-Cereceda, Pelin Sahlén, Per Eriksson, and Hanna M Björck, we present novel findings on regulatory factors on osteopontin (SPP1) expression in immune cells involved in degenerative ascending aortic aneurysms (AscAA). The central findings convey: SPP1 is a potential driver of the fibrotic endothelial-to-mesenchymal transition in AscAA. SPP1/osteopontin expression in AscAA is predominately by immune cells. ETS1 is a regulatory transcription factor of SPP1 expression in AscAA immune cells.

Asymmetric Schottky contacts induced via localized ultrafast laser irradiation for ultrasensitive, self-powered, 2D photodetectors

Self-powered photodetectors hold great promise for addressing power-related challenges in the “Internet of Things (IoT)” era. However, the self-powered performances of a metal-semiconductor-metal (MSM) structure photodetector are inherently limited due to the presence of the symmetric Schottky contacts, leading to canceling photocurrents in opposite directions, while constructing an asymmetric MSM structure demands complicated design or sustained external fields. Herein, we propose a novel contact engineering strategy based on localized femtosecond (fs) laser irradiation, achieving an asymmetric band structure in an MSM-structure photodetector with pristine symmetric Schottky contacts. As a result, a MoS2 photodetector that exhibits exceptional photoresponse and self-powered performances is successfully fabricated. The device type transitions from a photoconductor to a photodiode, exhibiting a significant improvement in the rectification ratio from 1 to > 104. A comprehensive study on fs laser-based contact engineering is conducted by investigating atom diffusion, element variation, and Schottky barrier height variation. Notably, the photodetector demonstrates an exceptional zero-bias responsivity of 1.72 A/W, with a short circuit current of 37.2 nA and maximum output electric power of 1.67 nW. Our work provides a new strategy for modifying the energy band structure and facilitates the fabrication of high-performance self-powered photodetectors.

Unconventional criticality, scaling breakdown, and diverse universality classes in the Wilson-Cowan model of neural dynamics.

The Wilson-Cowan model constitutes a paradigmatic approach to understanding the collective dynamics of networks of excitatory and inhibitory units. It has been profusely used in the literature to analyze the possible phases of neural networks at a mean-field level, e.g., assuming large fully connected networks. Moreover, its stochastic counterpart allows one to study fluctuation-induced phenomena, such as avalanches. Here we revisit the stochastic Wilson-Cowan model paying special attention to the possible phase transitions between quiescent and active phases. We unveil eight possible types of such transitions, including continuous ones with scaling behavior belonging to known universality classes-such as directed percolation and tricritical directed percolation-as well as six distinct ones. In particular, we show that under some special circumstances, at a so-called "Hopf tricritical directed percolation" transition, rather unconventional behavior is observed, including the emergence of scaling breakdown. Other transitions are discontinuous and show different types of anomalies in scaling and/or exhibit mixed features of continuous and discontinuous transitions. These results broaden our knowledge of the possible types of critical behavior in networks of excitatory and inhibitory units and are, thus, of relevance to understanding avalanche dynamics in actual neuronal recordings. From a more general perspective, these results help extend the theory of nonequilibrium phase transitions into quiescent or absorbing states.