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Seed shattering is a major problem in birdsfoot trefoil (Lotus corniculatus L.) seed production and limited information is available describing the effects of agronomic practices on shatter losses. The objectives of this research were to: (i) quantify the effects of soil-water availability on seed shatter and (ii) determine optimal harvest time on the basis of a heat unit method to minimize birdsfoot trefoil seed losses under western Oregon climatic conditions. Six treatments varying in water depletion percentage and replenishment amount were applied in 1994 and 1995 and two treatments in 1996 on a Woodburn silt loam soil (fine-silty, mixed, mesic Aquultic Argixeroll) near Corvallis, OR. The total amount of shattered seeds was correlated with total harvested seed yield (r = 0.93). Crop water stress index (CWSI) was inversely related to the percentage of seeds shattered (r = -0.76). Increasing amounts of applied water increased the potential of seed yield shattered (r = 0.65). Seed shatter losses fluctuated during the late-reproductive period, but were not influenced by irrigation or fluctuating climatic conditions. A total of 109 heat units (approximately 11 d), which were determined on the basis of a 10 ° C base temperature, were accumulated from the time of initial pod dehiscence until rapid seed shattering. The average seed yield losses due to shattering was 3 to 5.3 kg [ha.sup.-] [d.sup.-1]. The non-irrigated control treatment generally produced more seeds than irrigated treatments. It is, thus, best not to irrigate birdsfoot trefoil grown for seed in western Oregon because increasing amounts of irrigation water increased seed shattering., BIRDSFOOT TREFOIL is a perennial, non-bloating legume used for forage and hay production in the northeastern and midwestern USA as well as eastern Canada. Fairey (1994) identified some of the [...]

Forage legume seed crop responses to water stress differ for each species, so a single optimal water management strategy is not applicable. The objectives of this study were to determine the effects of irrigation timing and replenishment amount on birdsfoot trefoil (Lotus corniculatus L.) reproduction and seed yield in the Willamette Valley of western Oregon, USA. Six treatments varying in water depletion percentage and replenishment amount were applied in 1994 and 1995 on a Woodburn silt loam soil (fine-silty, mixed, mesic Aquultic Argix-eroll) near Corvallis. In 1996, only a low stress (LS) that met the weekly crop evapotranspirative demand and a non-irrigated control (C) treatment were investigated. In the first year of production, maintaining plants under low-stress conditions sustained flowering longer than with limited or no irrigation. Flowering was not affected by irrigation in the subsequent two production years. Total above-ground phytomass was correlated with the amount of irrigation water (r = 0.92). The C and all single application treatments had greater seed yields (SY) than the LS treatment in 1994. In 1995, all single application treatments had greater SY than the LS treatment. There was no difference between LS and C in 1995 and 1996. Umbel density and the number of seeds per pod were the primary determinants of total seed yield (r = 0.77 and 0.92, respectively). Optimal total seed production was achieved without supplemental irrigation under the humid temperate marine climatic conditions found in western Oregon., BIRDSFOOT TREFOIL is a perennial, non-bloating forage legume used for pasture, hay, and silage in the midwestern and northeastern USA and eastern Canada. Annual U.S. certified seed production is estimated [...]

Forage legume seed crop reproduction can be modified by regulating soil-water availability. However, responses to water stress differ for each species, so a single optimal water management strategy is not available for all crops. The objectives of this research were to determine the crop-water requirements and the optimal water management conditions for birdsfoot trefoil (Lotus corniculatus L.) when grown for seed production under humid temperate marine climatic conditions of western Oregon, USA. The experiment was conducted on a Woodburn silt loam soil (fine-silty, mixed, mesic Aquultic Argixeroll) near Corvallis. Four single-application treatments varying in water depletion percentage (30 and 60% of field capacity) and replenishment amount (50 and 100% of amount depleted) were applied in 1994 and 1995. A low-stress treatment (LS) that received two to three applications per week of the amount depleted since the last application and a non-irrigated control were also investigated in 1994, 1995, and 1996. Increasing amounts of applied water resulted in increased seasonal crop evapotranspiration ([ET.sub.c]) with plants grown under lowstress having the greatest [ET.sub.c] and non-irrigated control plants the least (r = 0.91). The fraction of available soil water used by non-irrigated plants was greatest and the LS treatment the least of all treatments. For non-irrigated conditions, the crop-water requirement ranged from 240 to 255 mm. Soil-water conditions favorable for high vegetative development were opposite of the conditions for optimal seed yield water-use efficiency. Unlike other forage legume seed crops, birdsfoot trefoil grown under these conditions required minimal or no supplemental irrigation to achieve maximal seed yield., Birdsfoot trefoil is a perennial forage legume used for hay, pasture, and silage in the midwestern and northeastern USA and eastern Canada. It is adapted to a wide range of [...]

The molecular mechanisms controlling the balance of quiescence and proliferation in adult neural stem cells (NSCs) are often deregulated in brain cancers such as glioblastoma multiforme (GBM). Previously, we reported that FOXG1, a forebrain-restricted neurodevelopmental transcription factor, is frequently upregulated in glioblastoma stem cells (GSCs) and limits the effects of cytostatic pathways, in part by repression of the tumour suppressor Foxo3. Here, we show that increased FOXG1 upregulates Foxo6, a more recently discovered FOXO family member with potential oncogenic functions. Although genetic ablation of Foxo6 in proliferating NSCs had no effect on the cell cycle or entry into quiescence, we found that Foxo6-null NSCs could no longer efficiently exit quiescence following FOXG1 elevation. Increased Foxo6 resulted in the formation of large acidic vacuoles, reminiscent of Pak1-regulated macropinocytosis. Consistently, Pak1 expression was upregulated by FOXG1 overexpression and downregulated upon FOXO6 loss in proliferative NSCs. These data suggest a pro-oncogenic role for FOXO6, downstream of GBM-associated elevated FOXG1, in controlling quiescence exit, and shed light on the potential functions of this underexplored FOXO family member., Competing Interests: Competing interests The authors declare no competing or financial interests., (© 2024. Published by The Company of Biologists Ltd.)

The literature on organizational resilience explores various viewpoints, ranging from strategies to recover after disruptions to proactive anticipation of threats. Formal models primarily focus on the ability to recover from shocks, analyzing factors like deviation from performance targets, recovery time, and potential adaptation in function and structure. However, incorporating anticipation into such models remains scarce. Additionally, existing anticipatory systems models often neglect key aspects of organizational behavior. This work addresses these gaps by introducing an agent-based modeling approach that integrates anticipation into organizational decision-making. Our computational model features agents embedded in different organizational structures who make decisions based on projected market states (levels and trends). These decisions are subject to delays in perceiving market conditions and vary depending on the organization's adaptive capacity to update its offering. We analyze different organizational structures and market behaviors (trend direction and volatility). Our results indicate that full connectivity among agents can be detrimental to organizational resilience, as it may reduce the diversity of anticipation strategies for forecasting the market. Conversely, either sparse or highly clustered networks demonstrate a greater ability, on average, to keep up with changing market levels and trends.

Disease-relevant in vivo tumor models are essential tools for both discovery and translational research. Here, we describe a highly genetically tractable technique for generating immunocompetent somatic glioblastoma (GBM) mouse models using piggyBac transposition and CRISPR-Cas9-mediated gene editing in wild-type mice. We describe steps to deliver plasmids into subventricular zone endogenous neural stem cells by injection and electroporation, leading to the development of adult tumors that closely recapitulate the histopathological, molecular, and cellular features of human GBM. For complete details on the use and execution of this protocol, please refer to Garcia-Diaz et al. 1 ., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Glioblastoma (GBM) recurrence originates from invasive margin cells that escape surgical debulking, but to what extent these cells resemble their bulk counterparts remains unclear. Here, we generated three immunocompetent somatic GBM mouse models, driven by subtype-associated mutations, to compare matched bulk and margin cells. We find that, regardless of mutations, tumors converge on common sets of neural-like cellular states. However, bulk and margin have distinct biology. Injury-like programs associated with immune infiltration dominate in the bulk, leading to the generation of lowly proliferative injured neural progenitor-like cells (iNPCs). iNPCs account for a significant proportion of dormant GBM cells and are induced by interferon signaling within T cell niches. In contrast, developmental-like trajectories are favored within the immune-cold margin microenvironment resulting in differentiation toward invasive astrocyte-like cells. These findings suggest that the regional tumor microenvironment dominantly controls GBM cell fate and biological vulnerabilities identified in the bulk may not extend to the margin residuum., Competing Interests: Declaration of interests H.H. is a co-founder of and equity holder in Omniscope, a scientific advisory board member of MiRXES, and a consultant to Moderna., (Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.)

Glioblastoma is thought to originate from neural stem cells (NSCs) of the subventricular zone that acquire genetic alterations. In the adult brain, NSCs are largely quiescent, suggesting that deregulation of quiescence maintenance may be a prerequisite for tumor initiation. Although inactivation of the tumor suppressor p53 is a frequent event in gliomagenesis, whether or how it affects quiescent NSCs (qNSCs) remains unclear. Here, we show that p53 maintains quiescence by inducing fatty-acid oxidation (FAO) and that acute p53 deletion in qNSCs results in their premature activation to a proliferative state. Mechanistically, this occurs through direct transcriptional induction of PPARGC1a, which in turn activates PPARα to upregulate FAO genes. Dietary supplementation with fish oil containing omega-3 fatty acids, natural PPARα ligands, fully restores quiescence of p53-deficient NSCs and delays tumor initiation in a glioblastoma mouse model. Thus, diet can silence glioblastoma driver mutations, with important implications for cancer prevention., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.)

Change is ubiquitous in the study of organizations. Organizational change is characterized by multiple perspectives, both conceptually and methodologically. Computational modeling efforts are not the exception. In this work, we aim to provide an analysis of computational modeling approaches to organizational change. For that, we first review published works that directly connect to developing knowledge in organizational change from a computational lens. Second, we offer an account of unexplored topics in computational organizational change. Last, we highlight the potentialities of computer simulation models based on agent interactions in regard to how they could contribute to the understanding of central issues in this organizational research subfield.

Adult neural stem cells (NSCs) must tightly regulate quiescence and proliferation. Single-cell analysis has suggested a continuum of cell states as NSCs exit quiescence. Here we capture and characterize in vitro primed quiescent NSCs and identify LRIG1 as an important regulator. We show that BMP-4 signaling induces a dormant non-cycling quiescent state (d-qNSCs), whereas combined BMP-4/FGF-2 signaling induces a distinct primed quiescent state poised for cell cycle re-entry. Primed quiescent NSCs (p-qNSCs) are defined by high levels of LRIG1 and CD9, as well as an interferon response signature, and can efficiently engraft into the adult subventricular zone (SVZ) niche. Genetic disruption of Lrig1 in vivo within the SVZ NSCs leads an enhanced proliferation. Mechanistically, LRIG1 primes quiescent NSCs for cell cycle re-entry and EGFR responsiveness by enabling EGFR protein levels to increase but limiting signaling activation. LRIG1 is therefore an important functional regulator of NSC exit from quiescence.

Background: Ligation-mediated PCR protocols have diverse uses including the identification of integration sites of insertional mutagens, integrating vectors and naturally occurring mobile genetic elements. For approaches that employ NGS sequencing, the relative abundance of integrations within a complex mixture is typically determined through the use of read counts or unique fragment lengths from a ligation of sheared DNA; however, these estimates may be skewed by PCR amplification biases and saturation of sequencing coverage., Results: Here we describe a modification of our previous splinkerette based ligation-mediated PCR using a novel Illumina-compatible adapter design that prevents amplification of non-target DNA and incorporates unique molecular identifiers. This design reduces the number of PCR cycles required and improves relative quantitation of integration abundance for saturating sequencing coverage. By inverting the forked adapter strands from a standard orientation, the integration-genome junction can be sequenced without affecting the sequence diversity required for cluster generation on the flow cell. Replicate libraries of murine leukemia virus-infected spleen samples yielded highly reproducible quantitation of clonal integrations as well as a deep coverage of subclonal integrations. A dilution series of DNAs bearing integrations of MuLV or piggyBac transposon shows linearity of the quantitation over a range of concentrations., Conclusions: Merging ligation and library generation steps can reduce total PCR amplification cycles without sacrificing coverage or fidelity. The protocol is robust enough for use in a 96 well format using an automated liquid handler and we include programs for use of a Beckman Biomek liquid handling workstation. We also include an informatics pipeline that maps reads, builds integration contigs and quantitates integration abundance using both fragment lengths and unique molecular identifiers. Suggestions for optimizing the protocol to other target DNA sequences are included. The reproducible distinction of clonal and subclonal integration sites from each other allows for analysis of populations of cells undergoing selection, such as those found in insertional mutagenesis screens., Competing Interests: Competing interestsNone., (© The Author(s). 2020.)

Alcohol intake is facilitated by its relationship with eating behavior and both processes are highly influenced by situations of stress and anxiety. The dysregulation of these processes can reach pathological situations such as anorexia, bulimia or obesity. The neurobiological elements which underlie this control are not completely clarified. The nucleus incertus (NI) in the pontine tegmentum is a common element in the food intake and alcoholism. NI is characterized by using the neuropeptide relaxin-3 (RLN3) as transmitter and its receptor RXFP3. In the present review, we will analyze the participation of the NI-RLN3-RXFP3 system in these behaviors under conditions of anxiety or stress in animal models. The activation of NI has a positive effect on intake (orexigenic) and generates a wide response in the amygdala modulating anxiety states. The activity of RLN3-RXFP3 in the amygdala could affect alcohol addiction since the application of the RXFP3 antagonist in extended amygdala attenuates the relapse to alcohol induced by stress. The neuroanatomical data indicate that the NI-RLN3-RXFP3 system acts on the feeding behavior and alcohol intake by means of projections parallel to the canonical mesolimbic pathways. Thus, data in animal models indicate that the NI-RLN3-RXFP3 system should be taken into account as a target in the future treatment of disorders of eating and alcohol addictive behaviors.

Increasingly diversity researchers call for further studies of group micro-processes and dynamics to understand the paradoxical effects of diversity on group performance. In this study, based on analyses of in-group, networked, homophilous interactions, we aim to explain further the effects of diversity on group performance in a parallel problem-solving task, both experimentally and computationally. We developed a 'whodunit' problem-solving experiment with 116 participants assigned to different-sized groups. Experimental results show that low diversity and high homophily levels are associated with lower performance while the effects of group size are not significant. To investigate this further, we developed an agent-based computational model (ABM), through which we inspected (a) the effect of different homophily and diversity strengths on performance, and (b) the robustness of such effects across group size variations. Overall, modeling results were consistent with our experimental findings, and revealed that the strength of homophily can drive diversity towards a positive or negative impact on performance. We also observed that increasing group size has a very marginal effect. Our work contributes to a better understanding of the implications of diversity in-group problem-solving by providing an integration of both experimental and computational perspectives in the analysis of group processes.

Mammalian neural stem cell (NSC) lines provide a tractable model for discovery across stem cell and developmental biology, regenerative medicine and neuroscience. They can be derived from foetal or adult germinal tissues and continuously propagated in vitro as adherent monolayers. NSCs are clonally expandable, genetically stable, and easily transfectable - experimental attributes compatible with targeted genetic manipulations. However, gene targeting, which is crucial for functional studies of embryonic stem cells, has not been exploited to date in NSC lines. Here, we deploy CRISPR/Cas9 technology to demonstrate a variety of sophisticated genetic modifications via gene targeting in both mouse and human NSC lines, including: (1) efficient targeted transgene insertion at safe harbour loci ( Rosa26 and AAVS1 ); (2) biallelic knockout of neurodevelopmental transcription factor genes; (3) simple knock-in of epitope tags and fluorescent reporters (e.g. Sox2-V5 and Sox2-mCherry ); and (4) engineering of glioma mutations ( TP53 deletion; H3F3A point mutations). These resources and optimised methods enable facile and scalable genome editing in mammalian NSCs, providing significant new opportunities for functional genetic analysis., (© 2017. Published by The Company of Biologists Ltd.)

Transcription activator-like effectors (TALEs) contain modular programmable DNA binding domains. Fusing TALEs with effector domains creates synthetic transcription factors (TALE-TFs) or nucleases (TALENs), enabling precise gene manipulations. The construction of TALEs remains challenging due to their repetitive sequences. Here we report a simple TALE assembly reaction (STAR) that enables individual laboratories to generate multiple TALEs in a facile manner. STAR uses an isothermal assembly ('Gibson assembly') that is labour- and cost-effective, accessible, rapid and scalable. A small 68-part fragment library is employed, and the specific TALE repeat sequence is generated within ~8 hours. Sequence-verified TALENs or TALE-TF plasmids targeting 17 bp target sequences can be produced within three days, without the need for stepwise intermediate plasmid production. We demonstrate the utility of STAR through production of functional TALE-TFs capable of activating human SOX2 expression. STAR addresses some of the shortcomings of existing Golden Gate or solid-phase assembly protocols and enables routine production of TALE-TFs that will complement emerging CRISPR/Cas9-based reagents across diverse applications in mammalian stem cell and synthetic biology.