The recent discovery of superconductivity in the iron oxypnictide family of compounds has generated intense interest. The layered crystal structure with transition-metal ions in planar square-lattice ...form and the discovery of spin-density-wave order near 130 K (refs 10, 11) seem to hint at a strong similarity with the copper oxide superconductors. An important current issue is the nature of the ground state of the parent compounds. Two distinct classes of theories, distinguished by the underlying band structure, have been put forward: a local-moment antiferromagnetic ground state in the strong-coupling approach, and an itinerant ground state in the weak-coupling approach. The first approach stresses on-site correlations, proximity to a Mott-insulating state and, thus, the resemblance to the high-transition-temperature copper oxides, whereas the second approach emphasizes the itinerant-electron physics and the interplay between the competing ferromagnetic and antiferromagnetic fluctuations. The debate over the two approaches is partly due to the lack of conclusive experimental information on the electronic structures. Here we report angle-resolved photoemission spectroscopy (ARPES) of LaOFeP (superconducting transition temperature, Tc = 5.9 K), the first-reported iron-based superconductor. Our results favour the itinerant ground state, albeit with band renormalization. In addition, our data reveal important differences between these and copper-based superconductors.
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DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Neuroimmune communication contributes to both baseline and adaptive physiological functions, as well as disease states. The vascular blood-brain barrier (BBB) and associated cells of the ...neurovascular unit (NVU) serve as an important interface for immune communication between the brain and periphery through the blood. Immune functions and interactions of the BBB and NVU in this context can be categorized into at least five neuroimmune axes, which include (1) immune modulation of BBB impermeability, (2) immune regulation of BBB transporters, secretions, and other functions, (3) BBB uptake and transport of immunoactive substances, (4) immune cell trafficking, and (5) BBB secretions of immunoactive substances. These axes may act separately or in concert to mediate various aspects of immune signaling at the BBB. Much of what we understand about immune axes has been from work conducted using in vitro BBB models, and recent advances in BBB and NVU modeling highlight the potential of these newer models for improving our understanding of how the brain and immune system communicate. In this review, we discuss how conventional in vitro models of the BBB have improved our understanding of the 5 neuroimmune axes. We further evaluate the existing literature on neuroimmune functions of novel in vitro BBB models, such as those derived from human induced pluripotent stem cells (iPSCs) and discuss their utility in evaluating aspects of neuroimmune communication.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
The whole-brain functional connectivity (FC) pattern obtained from resting-state functional magnetic resonance imaging data are commonly applied to study neuropsychiatric conditions such as autism ...spectrum disorder (ASD) by using different machine learning models. Recent studies indicate that both hyper- and hypo- aberrant ASD-associated FCs were widely distributed throughout the entire brain rather than only in some specific brain regions. Deep neural networks (DNN) with multiple hidden layers have shown the ability to systematically extract lower-to-higher level information from high dimensional data across a series of neural hidden layers, significantly improving classification accuracy for such data. In this study, a DNN with a novel feature selection method (DNN-FS) is developed for the high dimensional whole-brain resting-state FC pattern classification of ASD patients vs. typical development (TD) controls. The feature selection method is able to help the DNN generate low dimensional high-quality representations of the whole-brain FC patterns by selecting features with high discriminating power from multiple trained sparse auto-encoders. For the comparison, a DNN without the feature selection method (DNN-woFS) is developed, and both of them are tested with different architectures (i.e., with different numbers of hidden layers/nodes). Results show that the best classification accuracy of
is generated by the DNN-FS approach with 3 hidden layers and 150 hidden nodes (3/150). Remarkably, DNN-FS outperforms DNN-woFS for all architectures studied. The most significant accuracy improvement was
with the 3/150 architecture. The method also outperforms other feature selection methods, e.g., two sample
-test and elastic net. In addition to improving the classification accuracy, a Fisher's score-based biomarker identification method based on the DNN is also developed, and used to identify 32 FCs related to ASD. These FCs come from or cross different pre-defined brain networks including the default-mode, cingulo-opercular, frontal-parietal, and cerebellum. Thirteen of them are statically significant between ASD and TD groups (two sample
-test
< 0.05) while 19 of them are not. The relationship between the statically significant FCs and the corresponding ASD behavior symptoms is discussed based on the literature and clinician's expert knowledge. Meanwhile, the potential reason of obtaining 19 FCs which are not statistically significant is also provided.
•This paper uses the framework of the co-production of knowledge and social order to examine how knowledge–action systems work in the context of urban sustainable governance.•The paper presents and ...applies the knowledge–action systems analysis (KASA) approach to operationalize dynamics of co-production.•Existing institutional configurations and dynamics shape how knowledge is produced and used in policy-making.•Sustainability involves managing networks, politics of knowledge, and diverse social visions.•KASA can be used as a foundation to design new knowledge systems or joint-knowledge production efforts.
This paper examines how knowledge–action systems – the networks of actors involved in the production, sharing and use of policy-relevant knowledge – work in the process of developing sustainable strategies for cities. I developed an interdisciplinary framework – the knowledge–action system analysis (KASA) framework – that integrates concepts of the co-production of knowledge and social order with social network analysis tools to analyze existing configurations of knowledge–action systems in the city of San Juan, Puerto Rico, and how these are shaping both what we know and how we envision the future of cities. I applied KASA in the context of land use and green area governance and found that a diverse network of actors are contributing diverse knowledge types, thus showing potential for innovation in governance. This potential is conditioned, however, by various political and cultural factors, such as: (1) actors dominating knowledge about land use are the same ones that control urban land resources, (2) conventional planning expertise and procedures dominate over other alternative ways of knowing; (3) multiple visions and boundary arrangements co-exist in the city, and (4) boundary spanning opportunities limited by assumptions that knowledge and action should be done in distinct spheres of city planning. This study shows that developing adaptive and innovative capacities for sustainability is not solely a matter of harnessing more science, but about managing the politics of knowledge and visions that emerge from complex governance systems.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Abstract Purpose Foods, fluid intake, caffeine, alcohol, and tobacco may influence lower urinary tract symptoms (LUTS). Changes in these potentially modifiable non-urologic factors (NUF) are often ...suggested to improve LUTS. To better understand the relationship of NUFs with LUTS, we performed a systematic literature review to examine, grade, and summarize reported associations between LUTS and diet, fluid intake, caffeine, tobacco and alcohol use. Materials and Methods We performed PubMed searches for eligible articles providing evidence on associations between one or more NUF and LUTS. A modified Oxford system was used to grade the evidence. Results We reviewed 110 articles covering diet (n=28), fluid intake (n=21), caffeine (n=20), alcohol (n=26) and tobacco use (n=44). The evidence grade was generally low (6% level 1, 24% level 2, 11% level 3; 59% level 4). Fluid intake was associated with urinary frequency and urgency in men and women. Modest alcohol use was associated with less likelihood of benign prostatic hyperplasia (BPH) diagnosis and fewer LUTS in men. LUTS associations with food, caffeine, and tobacco were inconsistent. Conclusions Evidence for associations between LUTS and diet, fluid intake, caffeine, alcohol and tobacco use is sparse and mostly observational. However, there is evidence of associations between increased fluid intake and urinary frequency/urgency, and between modest alcohol intake and decreased BPH diagnosis and LUTS. Given the importance of these NUF to daily life, and their perceived impact on LUTS, higher quality evidence is needed.
Recent work investigating physiological mechanisms of working memory (WM) has revealed that modulation of alpha and beta frequency bands within the EEG plays a key role in WM storage. However, the ...nature of that role is unclear. In the present study, we examined event‐related desynchronization of alpha and beta (α/β‐ERD) elicited by visual tasks with and without a memory component to measure the impact of a WM demand on this electrophysiological marker. We recorded EEG from 60 healthy participants while they completed three variants on a typical change detection task: one in which participants passively viewed the sample array, passive (WM−); one in which participants viewed and attended the sample array in search of a target color but did not memorize the colors, active (WM−); and one in which participants encoded, attended to, and memorized the sample array, active (WM+). Replicating previous findings, we found that active (WM+) elicited robust α/β‐ERD in frontal and posterior electrode clusters and that α‐ERD was significantly associated with WM capacity. By contrast, α/β‐ERD was significantly smaller in the passive (WM−) and active (WM−) tasks, which did not consistently differ from one another. Furthermore, no such relationship was observed between WM capacity and desynchronization in the passive (WM−) or active (WM−) tasks. Taken together, these results suggest that α‐ERD during memory formation reflects a memory‐specific process such as consolidation or maintenance, rather than serving a generalized role in perceptual gating or engagement of attention.
Recently, task‐related desynchronization of the alpha and beta within the EEG during visual working memory (WM) formation and maintenance has been linked to individual differences in WM capacity. Here, we demonstrate that alpha/beta desynchronization elicited by a visual WM task appears to support a memory‐specific cognitive subprocess (e.g., consolidation), rather than a subprocess that is necessary, but not sufficient, for successful memory storage (e.g., encoding).
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BFBNIB, DOBA, FSPLJ, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UILJ, UKNU, UL, UM, UPUK
The blood-brain barrier (BBB) protects the central nervous system (CNS) from unregulated exposure to the blood and its contents. The BBB also controls the blood-to-brain and brain-to-blood permeation ...of many substances, resulting in nourishment of the CNS, its homeostatic regulation and communication between the CNS and peripheral tissues. The cells forming the BBB communicate with cells of the brain and in the periphery. This highly regulated interface changes with healthy aging. Here, we review those changes, starting with morphology and disruption. Transporter changes include those for amyloid beta peptide, glucose and drugs. Brain fluid dynamics, pericyte health and basement membrane and glycocalyx compositions are all altered with healthy aging. Carrying the
allele leads to an acceleration of most of the BBB's age-related changes. We discuss how alterations in the BBB that occur with healthy aging reflect adaptation to the postreproductive phase of life and may affect vulnerability to age-associated diseases.
Encephalitis can result in neurologic morbidity and mortality in children. Newly recognized infectious and noninfectious causes of encephalitis have become increasingly important over the past ...decade.
We retrospectively reviewed medical records from pediatric patients in Houston diagnosed with encephalitis in both an urban and rural catchment area between 2010 and 2017. We conducted an investigation to understand the etiology, clinical characteristics, and diagnostic testing practices in this population.
We evaluated 231 patients who met the case definition of encephalitis, among which 42% had no recognized etiology. Among those with an identified etiology, the most common were infectious (73; 31%), including viral (
= 51; 22%), with the most frequent being West Nile virus (WNV;
= 12), and bacterial (
= 19; 8%), with the most frequent being
(
= 7). Among cases of autoimmune encephalitis (
= 60; 26%), the most frequent cause was anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis (
= 31). Autoimmune causes were seen more commonly in female (
< .01) patients. Testing for herpes simplex virus and enterovirus was nearly universal; testing for anti-NMDAR encephalitis, WNV, and
was less common.
WNV was the most common infectious cause of encephalitis in our pediatric population despite lower testing frequency for WNV than herpes simplex virus or enterovirus. Increasing testing for anti-NMDAR encephalitis resulted in frequent identification of cases. Increased awareness and testing for WNV and
would likely result in more identified causes of pediatric encephalitis. Earlier etiologic diagnosis of encephalitides may lead to improve clinical outcomes.
The first neural crest cells to emigrate from the neural tube are specified as neurons and glial cells and are subsequently followed by melanocytes of the skin. We wished to understand how this fate ...switch is controlled. The transcriptional repressor FOXD3 is expressed exclusively in the neural/glial precursors and MITF is expressed only in melanoblasts. Moreover, FOXD3 represses melanogenesis. Here we show that avian MITF expression begins very early during melanoblast migration and that loss of MITF in melanoblasts causes them to transdifferentiate to a glial phenotype. Ectopic expression of FOXD3 represses MITF in cultured neural crest cells and in B16-F10 melanoma cells. We also show that FOXD3 does not bind directly to the MITF promoter, but instead interacts with the transcriptional activator PAX3 to prevent the binding of PAX3 to the MITF promoter. Overexpression of PAX3 is sufficient to rescue MITF expression from FOXD3-mediated repression. We conclude that FOXD3 controls the lineage choice between neural/glial and pigment cells by repressing MITF during the early phase of neural crest migration.
Oncogenes involved in recurrent chromosomal translocations serve as diagnostic markers and therapeutic targets in hematopoietic tumors. In contrast to myeloid and B-cell neoplasms, translocations in ...peripheral T-cell lymphomas (PTCLs) are poorly understood. Here, we identified recurrent translocations involving the multiple myeloma oncogene-1/interferon regulatory factor-4 (IRF4) locus in PTCLs. IRF4 translocations exist in myeloma and some B-cell lymphomas, but have not been reported earlier in PTCLs. We studied 169 PTCLs using fluorescence in situ hybridization and identified 12 cases with IRF4 translocations. Two cases with t(6;14)(p25;q11.2) had translocations between IRF4 and the T-cell receptor-alpha (TCRA) locus. Both were cytotoxic PTCLs, unspecified (PTCL-Us) involving bone marrow and skin. In total, 8 of the remaining 10 cases were cutaneous anaplastic large-cell lymphomas (ALCLs) without TCRA rearrangements (57% of cutaneous ALCLs tested). These findings identified IRF4 translocations as a novel recurrent genetic abnormality in PTCLs. Cytotoxic PTCL-Us involving bone marrow and skin and containing IRF4/TCRA translocations might represent a distinct clinicopathologic entity. Translocations involving IRF4 but not TCRA appear to occur predominantly in cutaneous ALCLs. Detecting these translocations may be useful in lymphoma diagnosis. Further, due to its involvement in translocations, MUM1/IRF4 protein may play an important biologic role in some PTCLs, and might represent a possible therapeutic target.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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