Miracle-dz/UniFAR-FTUs huggingface dataset:
Zinc uptake and radial transport in roots of Arabidopsis thaliana: a modelling approach to understand accumulation.

BACKGROUND AND AIMS Zinc uptake in roots is believed to be mediated by ZIP (ZRT-, IRT-like proteins) transporters. Once inside the symplast, zinc is transported to the pericycle, where it exits by means of HMA (heavy metal ATPase) transporters. The combination of symplastic transport and spatial separation of influx and efflux produces a pattern in which zinc accumulates in the pericycle. Here, mathematical modelling was employed to study the importance of ZIP regulation, HMA abundance and symplastic transport in creation of the radial pattern of zinc in primary roots of Arabidopsis thaliana. METHODS A comprehensive one-dimensional dynamic model of radial zinc transport in roots was developed and used to conduct simulations. The model accounts for the structure of the root consisting of symplast and apoplast and includes effects of water flow, diffusion and cross-membrane transport via transporters. It also incorporates the radial geometry and varying porosity of root tissues, as well as regulation of ZIP transporters. KEY RESULTS Steady-state patterns were calculated for various zinc concentrations in the medium, water influx and HMA abundance. The experimentally observed zinc gradient was reproduced very well. An increase of HMA or decrease in water influx led to loss of the gradient. The dynamic behaviour for a change in medium concentration and water influx was also simulated showing short adaptation times in the range of seconds to minutes. Slowing down regulation led to oscillations in expression levels, suggesting the need for rapid regulation and existence of buffering agents. CONCLUSIONS The model captures the experimental findings very well and confirms the hypothesis that low abundance of HMA4 produces a radial gradient in zinc concentration. Surprisingly, transpiration was found also to be a key parameter. The model suggests that ZIP regulation takes place on a comparable timescale as symplastic transport.
Cortical Mechanisms of Visual Recognition and Learning: A Hierarchical Kalman Filter Model

We describe a biologically plausible model of dynamic recognition and learning in the visual cortex based on the statistical theory of Kalman filtering from optimal control theory. The model utilizes a hierarchical network whose successive levels implement Kalman filters operating over successively larger spatial and temporal scales. Each hierarchical level in the network predicts the current visual recognition state at a lower level and adapts its own recognition state using the residual error between the prediction and the actual lower-level state. Simultaneously, the network also learns an internal model of the spatiotemporal dynamics of the input stream by adapting the synaptic weights at each hierarchical level in order to minimize prediction errors. The Kalman filter model respects key neuroanatomical data such as the reciprocity of connections between visual cortical areas, and assigns specific computational roles to the inter-laminar connections known to exist between neurons in the visual cortex. Previous work elucidated the usefulness of this model in explaining neurophysiological phenomena such as endstopping and other related extra-classical receptive field effects. In this paper, in addition to providing a more detailed exposition of the model, we present a variety of experimental results demonstrating the ability of this model to perform robust spatiotemporal segmentation and recognition of objects and image sequences in the presence of varying amounts of occlusion, background clutter, and noise.
Rate-distortion-based segmentation for MRC compression

Effective document compression algorithms require scanned document images be first segmented into regions such as text, pictures and background. In this paper, we present a document compression algorithm that is based on the 3-layer (foreground/mask/background)MRC (mixture raster content) model. This compression algorithm first segments a scanned document image into different classes. Then, each class is transformed to the 3-layer MRC model differently according to the property of that class. Finally, the foreground and the back-ground layers are compressed using JPEG with customized quantization tables. The mask layer is compressed using JBIG2. The segmentation is optimized in the sense of rate distortion for the 3-layer MRC representation. It works in a closed loop fashion by a lying each transformation to each region of the document and then selecting the method that yields the best rate-distortion trade-off. The proposed segmentation algorithm can not only achieve a better rate-distortion trade-off, but also produce more robust segmentations by eliminating those mis-classifications which can cause severe artifacts. At similar bit rates, our MRC compression with the rate- distortion based segmentation can achieve a much higher subjective quality than state-of-the-art compression algorithms, such as JPEG and JPEG-2000.
Separation of speech from interfering sounds based on oscillatory correlation

A multistage neural model is proposed for an auditory scene analysis task--segregating speech from interfering sound sources. The core of the model is a two-layer oscillator network that performs stream segregation on the basis of oscillatory correlation. In the oscillatory correlation framework, a stream is represented by a population of synchronized relaxation oscillators, each of which corresponds to an auditory feature, and different streams are represented by desynchronized oscillator populations. Lateral connections between oscillators encode harmonicity, and proximity in frequency and time. Prior to the oscillator network are a model of the auditory periphery and a stage in which mid-level auditory representations are formed. The model has been systematically evaluated using a corpus of voiced speech mixed with interfering sounds, and produces improvements in terms of signal-to-noise ratio for every mixture. The performance of our model is compared with other studies on computational auditory scene analysis. A number of issues including biological plausibility and real-time implementation are also discussed.
Blockade of CTLA-4 on CD4+CD25+ Regulatory T Cells Abrogates Their Function In Vivo1

Naturally occurring CD4+ regulatory T cells (TR) that express CD25 and the transcription factor FoxP3 play a key role in immune homeostasis, preventing immune pathological responses to self and foreign Ags. CTLA-4 is expressed by a high percentage of these cells, and is often considered as a marker for TR in experimental and clinical analysis. However, it has not yet been proven that CTLA-4 has a direct role in TR function. In this study, using a T cell-mediated colitis model, we demonstrate that anti-CTLA-4 mAb treatment inhibits TR function in vivo via direct effects on CTLA-4-expressing TR, and not via hyperactivation of colitogenic effector T cells. Although anti-CTLA-4 mAb treatment completely inhibits TR function, it does not reduce TR numbers or their homing to the GALT, suggesting the Ab mediates its function by blockade of a signal required for TR activity. In contrast to the striking effect of the Ab, CTLA-4-deficient mice can produce functional TR, suggesting that under some circumstances other immune regulatory mechanisms, including the production of IL-10, are able to compensate for the loss of the CTLA-4-mediated pathway. This study provides direct evidence that CTLA-4 has a specific, nonredundant role in the function of normal TR. This role has to be taken into account when targeting CTLA-4 for therapeutic purposes, as such a strategy will not only boost effector T cell responses, but might also break TR-mediated self-tolerance.
Profilin1 facilitates staurosporine-triggered apoptosis by stabilizing the integrin β1–actin complex in breast cancer cells

Profilin1 (Pfn1) functions as a tumour suppressor against malignant phenotypes of cancer cells. A minimum level of Pfn1 is critical for the differentiation of human epithelial cells, and its lower expression correlates with the tumourigenesis of breast cancer cells and tissues. However, the molecular mechanisms underlying its anti‐tumour action remain largely unknown. In this study, we found that stable expression of ectopic Pfn1 sensitized the breast cancer cell line MDA‐MB‐468 to apoptosis induced by staurosporine, a widely used natural apoptosis‐inducing agent. Pfn1 overexpression could also up‐regulate the expression of integrin α5β1, which has been shown to inhibit the transformed phenotype of cancer cells. Furthermore, the Pfn1‐facilitated apoptosis induced by staurosporine was blocked in cells attached to a supplementary fibronectin substrate, which serves as a ligand of integrin α5β1. These results suggest that the insufficient fibronectin caused by the integrin α5β1 up‐regulation might activate a signalling pathway leading to an increase of cellular apoptosis. Moreover, Pfn1 that primarily functions to promote local superstructure formation involving actin filaments and integrin β1 may contribute to its promotion on apoptosis. Our study indicated a previously uncharacterized role of Pfn1 in mediating staurosporine‐inducing apoptosis in breast cancer cells via up‐regulating integrin α5β1, and suggested a new target for breast cancer therapy.
CONTEMPORARY CORPORATE SOCIAL RESPONSIBILITY IN CHINA: AN EXTENSION OF CONFUCIAN PHILOSOPHY?

Current understandings of corporate social responsibility practices have been mainly driven by ‘western-centric’ evidence and philosophical approaches. China is undergoing an unprecedented industrial boom, and attention is rightfully turning to the practices and attitudes of Chinese firms in regard to corporate social responsibility. This exploratory study employs a multi-case method to examine CSR motivations, policies, and practices among 22 Chinese firms across a wide range of industries and business sectors. Findings indicate that factors such as industry type, pressures from multinational parent companies and/or overseas business customers, and internal firm motivations, such as maintaining a consistent workforce, affect the degree to which firms engage in corporate social behaviors. Furthermore, there appears to be a permeation of Confucian philosophical values within the reported practices and motivations among these firms. A theoretical model for examining CSR practices in Chinese firms is presented as an opening for future research.
Probabilistic mixed-model fault diagnosis

Previously-proposed strategies for VLSI fault diagnosis have suffered from a variety of self-imposed limitations. Some techniques are limited to a specific fault model, and many will fail in the face of any unmodeled behavior or unexpected data. Others apply ad-hoc or arbitrary scoring mechanisms to fault candidates, making the results difficult to interpret or to compare with the results from other algorithms. This paper outlines an approach to fault diagnosis that is robust, comprehensive, extendable, and practical. By introducing a probabilistic framework for diagnostic prediction, it is designed to incorporate disparate diagnostic algorithms, different sets of data, and a mixture of fault models into a single diagnostic result. Results from diagnosis experiments on a Hewlett-Packard ASIC and FIB inserted defects are presented.
Proving Termination of Logic Programs with Delay Declarations

In this paper we propose a method for proving termination of logic programs with delay declarations. The method is based on the notion of recurrent logic program, which is used to prove programs terminating with respect to an arbitrary selection rule. Most importantly, we use the notion of bound query (as proposed by M. Bezem) in the definition of cover, a new notion which forms the kernel of our approach. We introduce the class of delay recurrent programs and prove that programs in this class terminate for all local delay selection rules, provided that the delay conditions imply boundedness. The corresponding method can be also used to transform a logic program into a terminating logic program with delay declarations
Party membership and social movement activism: A macro–micro analysis

This article examines the macro–micro dynamics linking party membership with protest participation. We theorise that institutional and extra-institutional engagement are mutually reinforcing and that party membership has a positive effect on party activism. We examine key ideational and structural factors identified in the literature to analyse the relative importance of various factors for party members’ involvement. We look at micro-macro-level linkages by examining macro-level contextual variables as well as the extent to which these features mediate the individual-level effects. Our results suggest that party members support social movements for a variety of ideational and structural reasons but that strategic reasons are also important. Moreover, we find that contexts marked by more open political opportunities close the gap in social movement activism between party members and non-members suggesting that contexts with higher public spending as well as crises could be capitalised on to engage the wider public into political activism.
Effects of Oxidized Low Density Lipoprotein, Lipid Mediators and Statins on Vascular Cell Interactions

Abstract The integrin heterodimer CD11b/CD18 (αMβ2, Mac-1, CR3) expressed on monocytes or polymorphonuclear leukocytes (PMN) is a receptor for iC3b, fibrinogen, heparin, and for intercellular adhesion molecule (ICAM)-1 on endothelium, crucially contributing to vascular cell interactions in inflammation and atherosclerosis. In this report, we summarize our findings on the effects of lipid mediators and lipid-lowering drugs. Exposure of endothelial cells to oxidized low density lipoprotein (oxLDL) induces upregulation of ICAM-1 and increases adhesion of monocytic cells expressing Mac-1. Inhibition experiments show that monocytes use distinct ligands, i.e. ICAM-1 and heparan sulfate proteoglycans for adhesion to oxLDL-treated endothelium. An albumin-transferable oxLDL activity is inhibited by the antioxidant pyrrolidine dithiocarbamate (PDTC), while 8-epi-prostaglandin F2α (8-epi-PGF2α) or lysophosphatidylcholine had no effect, implicating yet unidentified radicals. Sequential adhesive and signaling events lead to the firm adhesion of rolling PMN on activated and adherent platelets, which may occupy areas of endothelial denudation. Shear-resistant arrest of PMN on thrombin-stimulated platelets in flow conditions requires distinct regions of Mac-1, involving its interactions with fibrinogen bound to platelet αllbβ3, and with other platelet ligands. Both arrest and adhesion strengthening under flow are stimulated by platelet-activating factor and leukotriene B4, but not by the chemokine receptor CXCR2. We tested whether Mac-1-dependent monocyte adhesiveness is affected by inhibitors of hydroxy-methylglutaryl-Coenzyme A reductase (statins) which improve morbidity and survival of patients with coronary heart disease. As compared to controls, adhesion of isolated monocytes to endothelium ex vivo was increased in patients with hypercholesterolemia. Treatment with statins decreased total and low density lipoprotein (LDL) cholesterol plasma levels, surface expression of Mac-1, and resulted in a dramatic reduction of Mac-1-mediated monocyte adhesion to endothelium. The inhibition of monocyte adhesion was reversed by mevalonate but not LDL in vitro, indicating that isoprenoid precursors are crucial for adhesiveness of Mac-1. Such effects may crucially contribute to the clinical benefit of statins, independent of cholesterol-lowering, and may represent a paradigm for novel, anti-inflammatory mechanisms of action by this class of drugs.
Maternal undernutrition programmes atherosclerosis in the ApoE*3-Leiden mouse

Poor quality of nutrition during fetal development is associated with adverse health outcomes in adult life. Epidemiological studies suggest that markers of fetal undernutrition are predictive of risk of the metabolic syndrome and CHD. Here we show that feeding a low-protein diet during pregnancy programmed the development of atherosclerosis in ApoE*3-Leiden mice. ApoE*3-Leiden mice carry a mutation of human ApoE*3 rendering them prone to atherosclerosis when fed a diet rich in cholesterol. It was noted that fetal exposure to protein restriction led to a greater degree of dyslipidaemia in mice when fed an atherogenic diet, with low-protein-exposed ApoE*3 mice having elevated total plasma cholesterol (34 % higher; P < 0·001) and TAG (39 % higher; P < 0·001) relative to offspring exposed to a control diet in utero. The low-protein group developed more severe atherosclerotic lesions within the aortic arch (2·61-fold greater lesion area; P < 0·001). Analysis of a targeted gene array suggested a potential role for members of the LDL receptor superfamily, along with similar programmed suppression of the mRNA expression of hepatic sterol regulatory element-binding protein-1c. This indicates that disordered lipid metabolism may play a role in the fetal programming of atherosclerosis in this model. Whereas earlier studies have shown early programming of cardiovascular risk factors, these results demonstrate for the first time that the interaction of prenatal undernutrition with a postnatal atherogenic diet increases the extent of atherosclerotic disease.
Observational evidence for a truncation of the star cluster initial mass function at the high mass end

We present the luminosity function (LF) of star clusters in M51 based on HST/ACS observations taken as part of the Hubble Heritage project. The clusters are selected based on their size and with the resulting 5990 clusters we present one of the largest cluster samples of a single galaxy. We find that the LF can be approximated with a double power-law distribution with a break around MV = −8.9. On the bright side the index of the power-law distribution is steeper (α = 2.75) than on the faint-side (α = 1.93), similar to what was found earlier for the “Antennae” galaxies. The location of the bend, however, occurs about 1.6 mag fainter in M51. We confront the observed LF with the model for the evolution of integrated properties of cluster populations of Gieles et al. (2006, A&A, accepted), which predicts that a truncated cluster initial mass function would result in a bend in, and a double power-law behaviour of, the integrated LF. The combination of the large field-of view and the high star cluster formation rate of M51 make it possible to detect such a bend in the LF. Hence, we conclude that there exists a fundamental upper limit to the mass of star clusters in M51. Assuming a power-law cluster initial mass function with exponentional cut-off of the form N dM ∝ M−β exp(−M/MC) dM, we find that MC = 105 M . A direct comparison with the LF of the “Antennae” suggests that there MC = 4 × 105 M .
Interdisciplinary Needs: The Current Context

MEETING THE INTERDISCIPLINARY NEEDS of today's library users begins with understanding the activities that create these needs. The answers to three basic questions provide the basis for a common discourse about those activities and their place in the knowledge system: (1) why and how do interdisciplinary activities emerge? (2) what form do they take? and (3) where are they located in institutions? Interdisciplinary activities are the result of historical and contemporary developments in disciplines, professions, and new interdisciplinary fields. Recent accounts indicate that interdisciplinarity is no longer peripheral to the academy but is regarded in many quarters as essential to the knowledge system. The cumulative effect of alternative organizations of knowledge and new social and cognitive forms exposes a lack of fit between interdisciplinary needs and existing knowledge taxonomies and classification schemes.
Competition and Disclosure

There are many laws that require sellers to disclose private information about the quality of their products. But the theoretical justification for these laws is not obvious: economic theory predicts that a seller will voluntarily disclose such quality information, however unfavorable, as long as it is costless to do so. Here we show that competitive pressures between firms can undermine this full disclosure result, and explain why it may be the case that only high-quality firms choose to disclose. In this setting, mandatory disclosure laws can promote competition and raise consumer surplus at the expense of firm profits, potentially increasing the efficiency of the market.
Perceived Interparental Conflict and Depressive Symptomatology in Emerging Adults: The Mediating Role of Aggressive Attitudes

ABSTRACT This cross-sectional study tested the effects of perceived interparental conflict on emerging adults’ depressive symptomatology as mediated by aggressive attitudes. The sample included 520 college students (58.1% females) aged 18–22 years old. Total, direct and indirect effects were calculated through the estimation of an OLS regression-based mediation model, controlling for gender. The results suggest that perceptions of interparental conflict and appraisals of threat and self-blame positively predict depressive symptoms. Also, the results indicate that (1) verbal aggressive attitudes negatively mediate the relationship between interparental conflict properties and depressive symptoms; (2) hostile attitudes positively mediate the association between both threat and self-blame appraisals and depressive symptoms; and (3) anger positively mediates the relationship between both interparental conflict properties and threat appraisal and depressive symptoms. Results are discussed in the context of emerging adults’ mental adjustment and aggression expression when dealing with interparental conflict.
Toward Generalizable Sociomaterial Inquiry: A Computational Approach for Zooming In and Out of Sociomaterial Routines

In this paper, a computational, mixed methods approach that combines qualitative analysis with a novel approach to sequence analysis for studying the entanglement of human activities and digital capabilities in organizational routines is described. The approach is scalable across multiple contexts and complements the dominant idiographic modes of sociomaterial inquiry. The approach is rooted in the epistemology of a "rational reconstruction" consistent with the interpretive stance underlying the sociomaterial position. It arms researchers with the means to seek and uncover regularities in the ways human activities and digital capabilities become entangled across contexts by enabling the identification and articulation of generalizable patterns of sociomaterial activity. The computational approach is founded on sequence-analytic techniques that originated from the field of computational biology (genetics), but are now gaining popularity in the study of temporally ordered social phenomena such as organizational routines. These techniques are extended by drawing upon theoretical insights gained within sociomaterial scholarship on how the digital and the social become entangled. By detecting the variation in activities, actors, artifacts, and affordances that comprise what we denote a sociomaterial routine, the approach directly attends to ways in which human actors and the material features of technology become entangled in patterns of practice. Beyond motivating and describing the approach, the different insights that researchers can generate through its application in the study of the digitalization of organizational routines are illustrated. We conclude by suggesting several lines of inquiry that can enrich sociomaterial research.