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In this study, we investigate how production Cooperatives with a Sharing Economy Business Model (CSE‐BMs) foster innovations in structurally weak rural places. Taking a place‐based social capital perspective, we argue that the strength of CSE‐BMs in developing process, service, product, and social innovation lies in their ability to reconfigure shared resources across communities and actors located on different levels of power and with different access to resources. Empirically, we reconstruct the mobilization and reconfiguration of shared resources across the network in an in‐depth case study of a CSE‐BM in rural Greece. We find that CSE‐BMs can mobilize resources across the network by offering value propositions that stakeholders regard as credible because decision‐makers show attachment to the place. To realize sufficient value for members to sustain their contributions to the CSE‐BM, product, service, and process innovations are complemented by social innovations. Mobilizing and reconfiguring shared resources across different interest groups unleashes the innovative potential of CSE‐BMs but causes tensions between different mindsets at the same time. Cooperatives offer an organizational structure to turn these tensions from a threat into an opportunity for innovation. Our findings contribute to the Sharing Economy Business Model (SE‐BM) literature on typology building and the construction of ideal types. We also advance the SE‐BM debate by shedding light on the potential of cooperative forms of organizing collaborative production in the sharing economy. Practically, we contribute to the discussion about the importance of physical vs. digital platforms as intermediaries in SE‐BMs. [ABSTRACT FROM AUTHOR]

We study structural conditions in dense graphs that guarantee the existence of vertex‐spanning substructures such as Hamilton cycles. It is easy to see that every Hamiltonian graph is connected, has a perfect fractional matching and, excluding the bipartite case, contains an odd cycle. A simple consequence of the Robust Expander Theorem of Kühn, Osthus and Treglown tells us that any large enough graph that robustly satisfies these properties must already be Hamiltonian. Our main result generalises this phenomenon to powers of cycles and graphs of sublinear bandwidth subject to natural generalisations of connectivity, matchings and odd cycles. This answers a question of Ebsen, Maesaka, Reiher, Schacht and Schülke and solves the embedding problem that underlies multiple lines of research on sufficient conditions for spanning structures in dense graphs. As applications, we recover and establish Bandwidth Theorems in a variety of settings including Ore‐type degree conditions, Pósa‐type degree conditions, deficiency‐type conditions, locally dense and inseparable graphs, multipartite graphs as well as robust expanders. [ABSTRACT FROM AUTHOR]

In 1980, Akiyama, Exoo and Harary posited the Linear Arboricity Conjecture which states that any graph G of maximum degree Δ can be decomposed into at most linear forests. (A forest is linear if all of its components are paths.) In 1988, Alon proved the conjecture holds asymptotically. The current best bound is due to Ferber, Fox and Jain from 2020 who showed that Δ 2 + O (Δ 0.661) suffices for large enough Δ . Here, we show that G admits a decomposition into at most Δ 2 + 3 Δ log 4 Δ linear forests provided Δ is large enough. Moreover, our result also holds in the more general list setting, where edges have (possibly different) sets of permissible linear forests. Thus our bound also holds for the List Linear Arboricity Conjecture which was only recently shown to hold asymptotically by Kim and the second author. Indeed, our proof method ties together the Linear Arboricity Conjecture and the well-known List Colouring Conjecture; consequently, our error term for the Linear Arboricity Conjecture matches the best known error-term for the List Colouring Conjecture due to Molloy and Reed from 2000. This follows as we make two copies of every colour and then seek a proper edge colouring where we avoid bicoloured cycles between a colour and its copy; we achieve this via a clever modification of the nibble method. [ABSTRACT FROM AUTHOR]

Neurons in the hypothalamic preoptic area (POA) regulate multiple homeostatic processes, including thermoregulation and sleep, by sensing afferent input and modulating sympathetic nervous system output. The POA has an autonomous circadian clock and may also receive circadian signals indirectly from the suprachiasmatic nucleus. We have previously defined a subset of neurons in the POA termed QPLOT neurons that are identified by the expression of molecular markers (Qrfp, Ptger3, LepR, Opn5, Tacr3) that suggest receptivity to multiple stimuli. Because Ptger3, Opn5, and Tacr3 encode G-protein coupled receptors (GPCRs), we hypothesized that elucidating the G-protein signaling in these neurons is essential to understanding the interplay of inputs in the regulation of metabolism. Here, we describe how the stimulatory Gs-alpha subunit (Gnas) in QPLOT neurons regulates metabolism in mice. We analyzed Opn5cre; Gnasfl/fl mice using indirect calorimetry at ambient temperatures of 22°C (a historical standard), 10°C (a cold challenge), and 28°C (thermoneutrality) to assess the ability of QPLOT neurons to regulate metabolism. We observed a marked decrease in nocturnal locomotion of Opn5cre; Gnasfl/fl mice at both 28°C and 22°C, but no overall differences in energy expenditure, respiratory exchange, or food and water consumption. To analyze daily rhythmic patterns of metabolism, we assessed circadian parameters including amplitude, phase, and MESOR. Loss-of-function GNAS in QPLOT neurons resulted in several subtle rhythmic changes in multiple metabolic parameters. We observed that Opn5cre; Gnasfl/fl mice show a higher rhythm-adjusted mean energy expenditure at 22°C and 10°C, and an exaggerated respiratory exchange shift with temperature. At 28°C, Opn5cre; Gnasfl/fl mice have a significant delay in the phase of energy expenditure and respiratory exchange. Rhythmic analysis also showed limited increases in rhythm-adjusted means of food and water intake at 22°C and 28°C. Together, these data advance our understanding of Gαs-signaling in preoptic QPLOT neurons in regulating daily patterns of metabolism. [ABSTRACT FROM AUTHOR]

Activating non-inherited mutations in the guanine nucleotide-binding protein G(q) subunit alpha (GNAQ) gene family have been identified in childhood vascular tumors. Patients experience extensive disfigurement, chronic pain and severe complications including a potentially lethal coagulopathy termed Kasabach-Merritt phenomenon. Animal models for this class of vascular tumors do not exist. This has severely hindered the discovery of the molecular consequences of GNAQ mutations in the vasculature and, in turn, the preclinical development of effective targeted therapies. Here we report a mouse model expressing hyperactive mutant GNAQ in endothelial cells. Mutant mice develop vascular and coagulopathy phenotypes similar to those seen in patients. Mechanistically, by transcriptomic analysis we demonstrate increased mitogen activated protein kinase signaling in the mutant endothelial cells. Targeting of this pathway with Trametinib suppresses the tumor growth by reducing vascular cell proliferation and permeability. Trametinib also prevents the development of coagulopathy and improves mouse survival. Life-threatening vascular tumors can be associated with uncontrolled activity of the guanine nucleotide-binding protein subunit alpha (Gαq). Here, the authors develop a murine model for these tumors and show that MEK inhibition prevents formation of vascular lesions and improves survival. [ABSTRACT FROM AUTHOR]

BACKGROUND: Evolving research suggests cockpit decompression at altitude occurs more frequently and at lower altitudes than previously reported. Aerospace decompression sickness (DCS) can present subtly and lead to morbid neurological sequelae, requiring high clinical suspicion maintained by pilots, first responders, and physicians. Current literature reflects a paucity of guidance detailing decision-making response algorithm. This report intends to address this knowledge gap by reviewing published guidelines to develop treatment decision protocols for medical providers. OVERVIEW: Aviation DCS mechanistically overlaps with its well-studied correlate in divers with a growing literature body stimulated by prior serial fatal aviation accidents within the United States Air Force U-2 community. Following narrative literature review on the occurrence of decompression injuries resulting from altitude exposure, best clinical practices were formatted as flow charts for algorithmic and universal approaches to medical care. Inflection points in decision-making incorporate both telephone/virtual and face-to-face evaluation with progressive escalations of treatment according to tiered level of care indicated. Three flow charts were developed for procedure following rapid decompression at altitude for utilization in clinical standard operating procedures, practice guidelines, or emergency response. These encompass presence of clinical symptoms at ground-level, self-assessment screening protocol for seeking care, and pre-hospital treatment guidelines for use in a Basic Life Support response system. DISCUSSION: Cockpit decompression at altitude occurs relatively infrequently, though the potential for morbid resulting injury mandates high clinical suspicion when indicated. Clinical sequelae overlap with correlates in the hyperbaric environment, which should be recognized by pilots, aircrew, relevant military personnel, air traffic controllers, and those who provide medical services to them. Established management frameworks facilitate prompt recognition of and initiation of treatment for decompression injuries at altitude. The proposed schema in this report thus serve to prevent related adverse medical incidents while guiding clinical decision making. Learning Objectives 1. The audience will understand updates about how aerospace decompression sickness (DCS) can to lead to morbid neurological sequelae, and the monitoring methods used including high clinical suspicion maintained by pilots, first responders, and physicians. 2. The audience will learn about current published guidelines in managing acute altitude decompression sickness (DCS) and their utility in developing updated treatment decision protocols for medical providers presented in this process review. [ABSTRACT FROM AUTHOR]

The 2022 annual National Toxicology Program Satellite Symposium, entitled "Pathology Potpourri," was held in Austin, Texas at the Society of Toxicologic Pathology's 40th annual meeting during a half-day session on Sunday, June 19. The goal of this symposium was to present and discuss challenging diagnostic pathology and/or nomenclature issues. This article presents summaries of the speakers' talks along with select images that were used by the audience for voting and discussion. Various lesions and topics covered during the symposium included induced and spontaneous neoplastic and nonneoplastic lesions in the mouse lung, spontaneous lesions in the reproductive tract of a female cynomolgus macaque, induced vascular lesions in a mouse asthma model and interesting case studies in a rhesus macaque, dog and genetically engineered mouse model. [ABSTRACT FROM AUTHOR]

Circadian clocks in the mammalian retina regulate a diverse range of retinal functions that allow the retina to adapt to the light-dark cycle. Emerging evidence suggests a link between the circadian clock and retinopathies though the causality has not been established. Here we report that clock genes are expressed in the mouse embryonic retina, and the embryonic retina requires light cues to maintain robust circadian expression of the core clock gene, Bmal1. Deletion of Bmal1 and Per2 from the retinal neurons results in retinal angiogenic defects similar to when animals are maintained under constant light conditions. Using two different models to assess pathological neovascularization, we show that neuronal Bmal1 deletion reduces neovascularization with reduced vascular leakage, suggesting that a dysregulated circadian clock primarily drives neovascularization. Chromatin immunoprecipitation sequencing analysis suggests that semaphorin signaling is the dominant pathway regulated by Bmal1. Our data indicate that therapeutic silencing of the retinal clock could be a common approach for the treatment of certain retinopathies like diabetic retinopathy and retinopathy of prematurity. Silencing of the retinal clock through targeting neuronal Bmal1 could constitute an approach to treating some forms of retinopathy. [ABSTRACT FROM AUTHOR]

Mammals maintain their internal body temperature within a physiologically optimal range. This involves the regulation of core body temperature in response to changing environmental temperatures and a natural circadian oscillation of internal temperatures. The preoptic area (POA) of the hypothalamus coordinates body temperature by responding to both external temperature cues and internal brain temperature. Here we describe an autonomous circadian clock system in the murine ventromedial POA (VMPO) in close proximity to cells which express the atypical violet-light sensitive opsin, Opn5. We analyzed the light-sensitivity and thermal-sensitivity of the VMPO circadian clocks ex vivo. The phase of the VMPO circadian oscillations was not influenced by light. However, the VMPO clocks were reset by temperature changes within the physiological internal temperature range. This thermal-sensitivity of the VMPO circadian clock did not require functional Opn5 expression or a functional circadian clock within the Opn5-expressing cells. The presence of temperature-sensitive circadian clocks in the VMPO provides an advancement in the understanding of mechanisms involved in the dynamic regulation of core body temperature. [ABSTRACT FROM AUTHOR]

Mammals maintain their internal body temperature within a physiologically optimal range. This involves the regulation of core body temperature in response to changing environmental temperatures and a natural circadian oscillation of internal temperatures. The preoptic area (POA) of the hypothalamus coordinates body temperature by responding to both external temperature cues and internal brain temperature. Here we describe an autonomous circadian clock system in the murine ventromedial POA (VMPO) in close proximity to cells which express the atypical violet-light sensitive opsin, Opn5. We analyzed the light-sensitivity and thermal-sensitivity of the VMPO circadian clocks ex vivo. The phase of the VMPO circadian oscillations was not influenced by light. However, the VMPO clocks were reset by temperature changes within the physiological internal temperature range. This thermal-sensitivity of the VMPO circadian clock did not require functional Opn5 expression or a functional circadian clock within the Opn5-expressing cells. The presence of temperature-sensitive circadian clocks in the VMPO provides an advancement in the understanding of mechanisms involved in the dynamic regulation of core body temperature. [ABSTRACT FROM AUTHOR]

Obtaining a parts list of the sensory components of the retina is vital to understand the effects of light in behavior, health, and disease. Rods, cones, and intrinsically photosensitive retinal ganglion cells (ipRGCs) are the best described photoreceptors in the mammalian retina, but recent functional roles have been proposed for retinal neuropsin (Opn5)—an atypical opsin. However, little is known about the pattern of Opn5 expression in the retina. Using cre (Opn5cre) and cre‐dependent reporters, we uncover patterns of Opn5 expression and find that Opn5 is restricted to retinal ganglion cells (RGCs). Opn5‐RGCs are nonhomogenously distributed through the retina, with greater densities of cells located in the dorsotemporal quadrant. In addition to the local topology of these cells, using cre‐dependent AAV viral tracing, we surveyed their central targets and found that they are biased towards image‐forming and image‐stabilizing regions. Finally, molecular and electrophysiological profiling reveal that Opn5‐RGCs comprise previously defined RGC types that respond optimally to edges and object‐motion (F‐mini‐ONs, HD2, HD1, LEDs, ooDSRGCs, etc.). Together, these data describe the second collection of RGCs that express atypical opsins in the mouse, and expand the roles of image‐forming cells in retinal physiology and function. [ABSTRACT FROM AUTHOR]

We develop a new framework to study minimum d$d$‐degree conditions in k$k$‐uniform hypergraphs, which guarantee the existence of a tight Hamilton cycle. Our main theoretical result deals with the typical absorption, path cover and connecting arguments for all k$k$ and d$d$ at once, and thus sheds light on the underlying structural problems. Building on this, we show that one can study minimum d$d$‐degree conditions of k$k$‐uniform tight Hamilton cycles by focusing on the inner structure of the neighbourhoods. This reduces the matter to an Erdös–Gallai‐type question for (k−d)$(k-d)$‐uniform hypergraphs, which is of independent interest. Once this framework is established, we can easily derive two new bounds. Firstly, we extend a classic result of Rödl, Ruciński and Szemerédi for d=k−1$d=k-1$ by determining asymptotically best possible degree conditions for d=k−2$d = k-2$ and all k⩾3$k \geqslant 3$. This was proved independently by Polcyn, Reiher, Rödl and Schülke. Secondly, we provide a general upper bound of 1−1/(2(k−d))$1-1/(2(k-d))$ for the tight Hamilton cycle d$d$‐degree threshold in k$k$‐uniform hypergraphs, thus narrowing the gap to the lower bound of 1−1/k−d$1-1/\sqrt {k-d}$ due to Han and Zhao. [ABSTRACT FROM AUTHOR]

If buildings are to play a role in reversing myopia trends, it is building professionals who will need to step up, prioritize myopia risk, and exhibit the collective will to design and engineer buildings that support eye health. Violet light transmission is related to myopia progression in adult high myopia. Myopia, also known as nearsightedness, is an eye disease that most often begins in early childhood and progresses through late adolescence. This has refocused the myopia field on the question of whether changes in the human living environment are causing myopia. [Extracted from the article]

Axon regeneration after spinal cord injury (SCI) is limited by both a decreased intrinsic ability of neurons to grow axons and the growth-hindering effects of extrinsic inhibitory molecules expressed around the lesion. Deletion of phosphatase and tensin homolog (Pten) augments mechanistic target of rapamycin (mTOR) signaling and enhances the intrinsic regenerative response of injured corticospinal neurons after SCI. Because of the variety of growth-restrictive extrinsic molecules, it remains unclear how inhibition of conserved inhibitory signaling elements would affect axon regeneration and rewiring after SCI. Moreover, it remains unknown how a combinatorial approach to modulate both extrinsic and intrinsic mechanisms can enhance regeneration and rewiring after SCI. In the present study, we deleted RhoA and RhoC, which encode small GTPases that mediate growth inhibition signals of a variety of extrinsic molecules, to remove global extrinsic pathways. RhoA/RhoC double deletion in mice suppressed retraction or dieback of corticospinal axons after SCI. In contrast, Pten deletion increased regrowth of corticospinal axons into the lesion core. Although deletion of both RhoA and Pten did not promote axon regrowth across the lesion or motor recovery, it additively promoted rewiring of corticospinal circuits connecting the cerebral cortex, spinal cord, and hindlimb muscles. Our genetic findings, therefore, reveal that a combinatorial approach to modulate both intrinsic and extrinsic factors can additively promote neural circuit rewiring after SCI. [ABSTRACT FROM AUTHOR]

Opsin photoreceptors outside of the central nervous system have been shown to mediate smooth muscle photorelaxation in several organs. We hypothesized that opsin receptor activation in the colon would have a similar effect and influence colonic motility. We detected Opsin 3 (OPN3) protein expression in the colonic wall and demonstrated that OPN3 was present in enteric neurons in the muscularis propria of the murine colon. Precontracted murine colon segments demonstrated blue light (BL) -mediated relaxation ex vivo. This photorelaxation was wavelength specific and was increased with the administration of the chromophore 9 -cis retinal and a G protein receptor kinase 2 (GRK2) inhibitor. Light-mediated relaxation of the colon was not inhibited by L-NAME or tetrodotoxin (TTX). Furthermore, BL exposure in the presence of 9 -cis retinal decreased the frequency of colonic migrating motor complexes (CMMC) in spontaneously contracting mouse colons ex vivo. These results demonstrate for the first time a receptor-mediated photorelaxation of colonic smooth muscle and implicate opsins as possible new targets in the treatment of spasmodic gastrointestinal dysmotility. [ABSTRACT FROM AUTHOR]

Here we investigate mechanisms underlying spontaneous phasic contractions (SPCs) and sympathetic control of contractility in the rat epididymis, a long tubular duct involved in transportation and maturation of sperm. Longitudinal contractions of short segments (~ 1.5 mm) of rat proximal and distal caudal epididymal duct were measured + / − nerve stimulation. The extent of sympathetic innervation of these duct regions was determined by immunohistochemistry. Proximal caudal duct segments (150–300 μm dia.) exhibited SPCs, while distal segments (350–500 μm) were quiescent in ~ 80% of preparations. SPC amplitude and frequency were reduced by the L-type voltage-dependent Ca2+ channel (LVDCC) blocker nifedipine (1 μM), with the T-type voltage-dependent Ca2+ channel (TVDCC) blocker ML218 (1 μM) specifically decreasing SPC frequency. SPCs were inhibited upon blockade of the SR/ER Ca2+-ATPase (CPA 10 μM). SPCs were also inhibited by caffeine (1 μM), 2-APB (100 μM), niflumic acid (100 μM), or by lowering extracellular [Cl−] from 134.4 to 12.4 mM but not by ryanodine (25 μM) or tetracaine (100 μM). Electrical field stimulation (EFS) at 2 Hz for 60 s caused a sustained α1-adrenoceptor-sensitive contraction in distal segments and enhanced and/or induced α2-adrenoceptor-sensitive oscillatory phasic contractions in proximal and distal segments, the latter mimicked by application of the α2-adrenoceptor agonist clonidine. We hypothesise that SPCs in the proximal cauda are triggered by pacemaker mechanisms involving rhythmic IP3 receptor–operated SR/ER store Ca2+ release and resultant activation of CaCC with TVDCCs and possibly LVDCCs subserving in this process. Sympathetic nerve-released noradrenaline induces α2-adrenoceptor-mediated phasic contractions in the proximal and distal cauda. These findings provide new pharmacological targets for male infertility and contraception. [ABSTRACT FROM AUTHOR]

Myopia has become a major public health concern, particularly across much of Asia. It has been shown in multiple studies that outdoor activity has a protective effect on myopia. Recent reports have shown that short-wavelength visible violet light is the component of sunlight that appears to play an important role in preventing myopia progression in mice, chicks, and humans. The mechanism underlying this effect has not been understood. Here, we show that violet light prevents lens defocus-induced myopia in mice. This violet light effect was dependent on both time of day and retinal expression of the violet light sensitive atypical opsin, neuropsin (OPN5). These findings identify Opn5-expressing retinal ganglion cells as crucial for emmetropization in mice and suggest a strategy for myopia prevention in humans. [ABSTRACT FROM AUTHOR]

The preoptic area of the hypothalamus is a homeostatic control center. The heterogeneous neurons in this nucleus function to regulate the sleep/wake cycle, reproduction, thirst and hydration, as well as thermogenesis and other metabolic responses. Several recent studies have analyzed preoptic neuronal populations and demonstrated neuronal subtype-specific roles in suppression of thermogenesis. These studies showed similar thermogenesis responses to chemogenetic modulation, and similar synaptic tracing patterns for neurons that were responsive to cold, to inflammatory stimuli, and to violet light. A reanalysis of single-cell/nucleus RNA-sequencing datasets of the preoptic nucleus indicate that these studies have converged on a common neuronal population that when activated, are sufficient to suppress thermogenesis. Expanding on a previous name for these neurons (Q neurons, which reflect their ability to promote quiescence and expression of Qrfp), we propose a new name: QPLOT neurons, to reflect numerous molecular markers of this population and to capture its broader roles in metabolic regulation. Here, we summarize previous findings on this population and present a unified description of QPLOT neurons, the excitatory preoptic neuronal population that integrate a variety of thermal, metabolic, hormonal and environmental stimuli in order to regulate metabolism and thermogenesis. [ABSTRACT FROM AUTHOR]

Animals have evolved light-sensitive G protein–coupled receptors, known as opsins, to detect coherent and ambient light for visual and nonvisual functions. These opsins have evolved to satisfy the particular lighting niches of the organisms that express them. While many unique patterns of evolution have been identified in mammals for rod and cone opsins, far less is known about the atypical mammalian opsins. Using genomic data from over 400 mammalian species from 22 orders, unique patterns of evolution for each mammalian opsins were identified, including photoisomerases, RGR-opsin (RGR) and peropsin (RRH), as well as atypical opsins, encephalopsin (OPN3), melanopsin (OPN4), and neuropsin (OPN5). The results demonstrate that OPN5 and rhodopsin show extreme conservation across all mammalian lineages. The cone opsins, SWS1 and LWS, and the nonvisual opsins, OPN3 and RRH, demonstrate a moderate degree of sequence conservation relative to other opsins, with some instances of lineage-specific gene loss. Finally, the photoisomerase, RGR, and the best-studied atypical opsin, OPN4, have high sequence diversity within mammals. These conservation patterns are maintained in human populations. Importantly, all mammalian opsins retain key amino acid residues important for conjugation to retinal-based chromophores, permitting light sensitivity. These patterns of evolution are discussed along with known functions of each atypical opsin, such as in circadian or metabolic physiology, to provide insight into the observed patterns of evolutionary constraint. [ABSTRACT FROM AUTHOR]

Given a family of graphs scrF, we prove that the normalized edit distance of any given graph Gamma to being induced scrF -free is estimable with a query complexity that depends only on the bounds of the Frieze--Kannan regularity lemma and on a removal lemma for scrF. [ABSTRACT FROM AUTHOR]

This paper is a salvage report on Turner Rockshelter (36Ar96) and Smittman Rockshelter (36Ar38), and provides new information on Turner Cave (36Bt509). All three sites are located in close proximity to each other in western Pennsylvania. Turner and Smittman rockshelters were excavated by amateur archaeologists in the late 1950s and early 1960s, but the results were never published. In subsequent years the field notes were lost, and the collections dispersed. Thankfully, some documentation on Turner Rockshelter and large portions of the Turner and Smittman collections have been relocated and studied. As this report demonstrates, all three sites were visited by native people from Archaic times through the Late Prehistoric periods. Turner Rockshelter also produced some interesting early historic artifacts. [ABSTRACT FROM AUTHOR]

Erdős, Gyárfás and Pyber showed that every r-edge-coloured complete graph Kn can be covered by 25 r2 log r vertex-disjoint monochromatic cycles (independent of n). Here we extend their result to the setting of binomial random graphs. That is, we show that if $p = p(n) = \Omega(n^{-1/(2r)})$ , then with high probability any r-edge-coloured G(n, p) can be covered by at most 1000r4 log r vertex-disjoint monochromatic cycles. This answers a question of Korándi, Mousset, Nenadov, Škorić and Sudakov. [ABSTRACT FROM AUTHOR]

Recently, we characterized blue light--mediated relaxation (photorelaxation) of airway smooth muscle (ASM) and implicated the involvement of opsin 3 (OPN3), an atypical opsin. In the present study, we characterized the cellular signaling mechanisms of photorelaxation. We confirmed the functional role of OPN3 in blue light photorelaxation using trachea from OPN3 null mice (maximal relaxation 52 ± 13% compared with wild-type mice 90 ± 4.3%, P < 0.05). We then demonstrated colocalization of OPN3 and Gαs using co-IP and proximity ligation assays in primary human ASM cells, which was further supported by an increase in cAMP in mouse trachea treated with blue light compared with dark controls (23 ± 3.6 vs. 14 ± 2.6 pmol cAMP/ring, P < 0.05). Downstream PKA (protein kinase A) involvement was shown by inhibiting photorelaxation using Rp-cAMPS (P < 0.0001). Moreover, we observed converging mechanisms of desensitization by chronic β2-agonist exposure in mouse trachea and correlated this finding with colocalization of OPN3 and GRK2 (G protein receptor kinase) in primary human ASM cells. Finally, an overexpression model of OPN1LW (a red light photoreceptor in the same opsin family) in human ASM cells showed an increase in intracellular cAMP levels following red light exposure compared with nontransfected cells (48 ± 13 vs. 13 ± 2.1 pmol cAMP/mg protein, P < 0.01), suggesting a conserved photorelaxation mechanism for wavelengths of light that are more tissue penetrant. Together, these results demonstrate that blue light photorelaxation in ASM is mediated by the OPN3 receptor interacting with Gαs, which increases cAMP levels, activating PKA and modulated by GRK2. [ABSTRACT FROM AUTHOR]

Aims: As PDGFRα (+) cells appear not to suppress the excitability of detrusor smooth muscle by generating SK3‐dependent hyperpolarising as proposed in the gastrointestinal tract, we further explored the functional roles of PDGFRα (+) cells in regulating the spontaneous activity of urogenital tissues. Methods: Using PDGFRα‐eGFP mice, intracellular Ca2+ signaling in PDGFRα (+) cells of the bladder lamina propria, renal pelvis, and seminal vesicle were visualized using Cal‐590 fluorescence. The distribution and SK3 expression of PDGFRα (+) cells were also examined by immunohistochemistry. Results: In the bladder lamina propria, SK3 (−) PDGFRα (+) cells exhibited spontaneous Ca2+ transients and responded to stimulation of P2Y1 purinoceptors with MRS2365 (100 nM) or adenosine diphosphate (ADP) (100 μM) by developing Ca2+ transients. In the proximal renal pelvis, PDGFRα (+) cells were distributed in the mucosal, muscular and serosal layers but did not express SK3 immunoreactivity. PDGFRα (+) cells in the musculature resembling atypical smooth muscle cells generated spontaneous Ca2+ transients that were partially suppressed upon P2Y1‐stimulation, while vigorously responding to human angiotensin II (100 nM). In the seminal vesicle, PDGFRα (+) cells in the musculature but not mucosa expressed SK3 immunoreactivity. In the mucosa, the P2Y1 stimulation evoked Ca2+ transients in both PDGFRα (+) cells and PDGFRα (−) cells. Conclusion: PDGFRα (+) cells in spontaneously active urogenital tissues display heterogeneity in terms of their SK3 expression and P2Y1‐induced Ca2+ responses. Muscular PDGFRα (+) cells in the renal pelvis and mucosal PDGFRα (+) cells in the seminal vesicle may generate depolarizing signals to drive smooth muscle cells. [ABSTRACT FROM AUTHOR]

There has been substantial interest in estimating the value of a graph parameter, i.e. of a real-valued function defined on the set of finite graphs, by querying a randomly sampled substructure whose size is independent of the size of the input. Graph parameters that may be successfully estimated in this way are said to be testable or estimable, and the sample complexity qz = qz(ε) of an estimable parameter z is the size of a random sample of a graph G required to ensure that the value of z(G) may be estimated within an error of ε with probability at least 2/3. In this paper, for any fixed monotone graph property P = Forb(F), we study the sample complexity of estimating a bounded graph parameter zℱ that, for an input graph G, counts the number of spanning subgraphs of G that satisfy P. To improve upon previous upper bounds on the sample complexity, we show that the vertex set of any graph that satisfies a monotone property P may be partitioned equitably into a constant number of classes in such a way that the cluster graph induced by the partition is not far from satisfying a natural weighted graph generalization of P. Properties for which this holds are said to be recoverable, and the study of recoverable properties may be of independent interest. [ABSTRACT FROM AUTHOR]

The paper aims to take forward recent research concerning the development of grassroots innovations and sustainability transitions in housing. We introduce and empirically assess a multi-level, process-oriented framework informed by strategic niche management (SNM) and social capital theory. Drawing on qualitative data, the empirical part explores the emergence of community-led housing (CLH) in England as a grassroots-based housing niche which operates in a context of market dysfunction. The paper offers further conceptual development of the role of intermediaries in grassroots niche building. Our findings suggest an evolution from independent sub-niche umbrellas to broader-based intermediaries to leverage and consolidate different sustainability practices in the niche. The results question an unadapted application of the simplistic growth-oriented SNM approach advocating for strategic coherence. In particular, our analysis shows that the development of broader-based intermediary organisations is driven by short-term government funding and carefully preserves the diversity of approaches and identities within the niche. [ABSTRACT FROM AUTHOR]

The paper aims to develop a better understanding of the evolution and structuration of contemporary civil society fields. It applies analytical elements from field theories and closely related network governance literature within a qualitative research design to explore collective action around community-led housing (CLH) in England, a label assigned to a range of alternative housing models. We argue that collective action needs to be understood as a loose coupling of earlier and younger social movements, based on their shared awareness of and willingness to address macro-level societal problems. We further identify a gradual evolution of field governance from loose covenanting between sub-fields, development of a common project, to network activation to manage significant external funding. This process has not yet led to a unified field with stable internal governance and wide external legitimacy on the national level. However, an embryonic field structure and permeable boundaries provide CLH actors multiple hybrid identities and strategic positioning opportunities in adjacent fields. We believe that our strategic field perspective can shed light on the nature of collective action in other parts of the civil society. [ABSTRACT FROM AUTHOR]

Europe is witnessing a new wave of collective self-organized forms of housing provision. We refer to the wide variety of these forms under the umbrella term "Collaborative Housing". Alongside growing grassroots activity, the number and breadth of academic publications is rapidly growing. Nevertheless, the field remains thematically fragmented, with literature spread across disciplines. This article aims to establish a basis for greater conceptual clarity by exploring the domain of collaborative housing research over the period of 1990–2017. We carry out a thematic mapping and assessment covering 195 relevant peer-reviewed journal articles in English, German and French. These are inductively synthesized and categorized into five main thematic areas: socio-demographic, collaboration, motivation, effects and context. We conclude that the systematic and inductive approach of our review unravels new perspectives and makes the case for the conceptualization of collaborative housing as an independent research field, providing a basis for further theory development. [ABSTRACT FROM AUTHOR]

Since the 2000s many European countries have seen the re-emergence of a range of collective self-organized and participatory forms of housing provision. Collaborative housing (CH) has been adopted by many researchers and practitioners over the last decades as an umbrella term to encompass the wide variety that these forms of housing can take. Clearer definitions of CH practices would help us identify the potential and limits of these housing types to address a variety of (new) housing needs, notably vis-a-vis other types of housing provision. Their conceptualization of CH as the domain of "bricoleurs" or "makers" emphasies the agency of residents who collectively display creativity and resourcefulness to customize their own homes and "obtain housing that is not easily available in the standard housing production" (p.7). [Extracted from the article]

Impedance spectroscopy has been used to investigate the conductivity displayed by diamond doped with boron in an intrinsic-δ-layer-intrinsic multilayer system with differing δ-layer thicknesses. Carrier transport within 5 nm δ-layer structures is complex, being dominated by conduction in the interfacial regions between the δ-layer and the intrinsic regions, as well as conduction within the δ-layer itself. In the case of 3.2 nm thick δ-layers the situation appears improved with uncapped samples supporting only two conduction paths, one of which may be associated with transport outside of the δ-layer, the other low transport within the δ-layer complex diamond structures. Introduction of the capping layer creates a third conduction path associated with unwanted boron in the capping layer-δ-layer interface. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 29-year old woman suffering from mutilated occlusion and anterior splaying of teeth. No medications were being taken by the patient and no allergies to antibiotics was revealed. It discusses the effect of local tetracycline therapy of the periodontium during orthodontic treatment. Results show that the treatment reduced the maxillary incisor protrusion and rotations. The therapy led to a normal clinical status, allowing effective orthodontic movements.

The aim of this paper is to investigate how the institutional context influences the configuration of collaborative housing models in Austria. Although Austria has a well-established cooperative sector, few empirical studies and no comprehensive overviews have been published on collaborative housing. This paper aims to fill this research gap by extending existing work on organisational models within Austrian non-profit housing. The contribution reports original research based on qualitative expert interviews and case studies completed in 2015. We focus our empirical analysis on two local housing contexts with current collaborative housing activity, Vienna and Salzburg. Our findings highlight the importance of partnerships with large cooperatives and the key role of local authorities for the development of collaborative housing initiatives. The main contributions of the paper can be seen in feeding into on-going international comparative research on collaborative housing sectors and on the changing institutional landscapes of housing systems. [ABSTRACT FROM PUBLISHER]