660 research outputs found
Development of a high temperature battery final report
Development of battery with lithium-magnesium alloy anode, molten cuprous chloride cathode, and zeolite separator cells and cupric oxide cathode and porous glass separator cell
Is attending a mental process?
The nature of attention has been the topic of a lively research programme in psychology for over a century. But there is widespread agreement that none of the theories on offer manage to fully capture the nature of attention. Recently, philosophers have become interested in the debate again after a prolonged period of neglect. This paper contributes to the project of explaining the nature of attention. It starts off by critically examining Christopher Mole’s prominent “adverbial” account of attention, which traces the failure of extant psychological theories to their assumption that attending is a kind of process. It then defends an alternative, process-based view of the metaphysics of attention, on which attention is understood as an activity and not, as psychologists seem to implicitly assume, an accomplishment. The entrenched distinction between accomplishments and activities is shown to shed new light on the metaphysics of attention. It also provides a novel diagnosis of the empirical state of play
Clinical and Epidemiological Characteristics of 1,420 European Patients with mild-to-moderate Coronavirus Disease 2019
Background: The clinical presentation of European patients with mild-to-moderate Covid-19 infection is still unknown. Objective: To study the clinical presentation of Covid-19 in Europe. Methods: Patients with positive diagnosis of Covid-19 were recruited from 18 European hospitals. Epidemiological and clinical data were obtained through a standardized questionnaire. Bayesian analysis was used for analyzing the relationship between outcomes. Results: 1,420 patients completed the study (962 females, 30.7% of health care workers). The mean age of patients was 39.17\ub112.09 years. The most common symptoms were headache (70.3%), loss of smell (70.2%), nasal obstruction (67.8%), cough (63.2%), asthenia (63.3%), myalgia (62.5%), rhinorrhea (60.1%), gustatory dysfunction (54.2%) and sore throat (52.9%). Fever was reported by on 45.4%. The mean duration of Covid-19 symptoms of mild-to-moderate cured patients was 11.5\ub15.7 days. The prevalence of symptoms significantly varied according to age and sex. Young patients more frequently had ear, nose, and throat complaints, whereas elderly individuals often presented fever, fatigue and loss of appetite. Loss of smell, headache, nasal obstruction and fatigue were more prevalent in female patients. The loss of smell was a key symptom of mild-to-moderate Covid19 patients and was not associated with nasal obstruction and rhinorrhea. Loss of smell persisted at least 7 days after the disease in 37.5% of cured patients. Conclusion: The clinical presentation of mild-to-moderate Covid-19 substantially varies according to the age and the sex characteristics of patients. Olfactory dysfunction seems to be an important underestimated symptom of mild-to-moderate Covid-19 that needs to be recognized as such by the WHO
Risks, benefits, and knowledge gaps of non-native tree species in Europe
Changing ecosystem conditions and diverse socio-economical events have contributed to an ingrained presence of non-native tree species (NNTs) in the natural and cultural European landscapes. Recent research endeavors have focused on different aspects of NNTs such as legislation, benefits, and risks for forestry, emphasizing that large knowledge gaps remain. As an attempt to fulfill part of these gaps, within the PEN-CAFoRR COST Action (CA19128) network, we established an open-access questionnaire that allows both academic experts and practitioners to provide information regarding NNTs from 20 European countries. Then, we integrated the data originating from the questionnaire, related to the country-based assessment of both peer-reviewed and grey literature, with information from available datasets (EUFORGEN and EU-Forest), which gave the main structure to the study and led to a mixed approach review. Finally, our study provided important insights into the current state of knowledge regarding NNTs. In particular, we highlighted NNTs that have shown to be less commonly addressed in research, raising caution about those characterized by an invasive behavior and used for specific purposes (e.g., wood production, soil recultivation, afforestation, and reforestation). NNTs were especially explored in the context of resilient and adaptive forest management. Moreover, we emphasized the assisted and natural northward migration of NNTs as another underscored pressing issue, which needs to be addressed by joint efforts, especially in the context of the hybridization potential. This study represents an additional effort toward the knowledge enhancement of the NNTs situation in Europe, aiming for a continuously active common source deriving from interprofessional collaboration. Copyright © 2022 Dimitrova, Csilléry, Klisz, Lévesque, Heinrichs, Cailleret, Andivia, Madsen, Böhenius, Cvjetkovic, De Cuyper, de Dato, Ferus, Heinze, Ivetić, Köbölkuti, Lazarević, Lazdina, Maaten, Makovskis, Milovanović, Monteiro, Nonić, Place, Puchalka and Montagnoli
Bidirectional Transcription Directs Both Transcriptional Gene Activation and Suppression in Human Cells
Small RNAs targeted to gene promoters in human cells have been shown to modulate both transcriptional gene suppression and activation. However, the mechanism involved in transcriptional activation has remained poorly defined, and an endogenous RNA trigger for transcriptional gene silencing has yet to be identified. Described here is an explanation for siRNA-directed transcriptional gene activation, as well as a role for non-coding antisense RNAs as effector molecules driving transcriptional gene silencing. Transcriptional activation of p21 gene expression was determined to be the result of Argonaute 2–dependent, post-transcriptional silencing of a p21-specific antisense transcript, which functions in Argonaute 1–mediated transcriptional control of p21 mRNA expression. The data presented here suggest that in human cells, bidirectional transcription is an endogenous gene regulatory mechanism whereby an antisense RNA directs epigenetic regulatory complexes to a sense promoter, resulting in RNA-directed epigenetic gene regulation. The observations presented here support the notion that epigenetic silencing of tumor suppressor genes, such as p21, may be the result of an imbalance in bidirectional transcription levels. This imbalance allows the unchecked antisense RNA to direct silent state epigenetic marks to the sense promoter, resulting in stable transcriptional gene silencing
Broadening INPP5E phenotypic spectrum: detection of rare variants in syndromic and non-syndromic IRD
Pathogenic variants in INPP5E cause Joubert syndrome (JBTS), a ciliopathy with retinal involvement. However, despite sporadic cases in large cohort sequencing studies, a clear association with non-syndromic inherited retinal degenerations (IRDs) has not been made. We validate this association by reporting 16 non-syndromic IRD patients from ten families with bi-allelic mutations in INPP5E. Additional two patients showed early onset IRD with limited JBTS features. Detailed phenotypic description for all probands is presented. We report 14 rare INPP5E variants, 12 of which have not been reported in previous studies. We present tertiary protein modeling and analyze all INPP5E variants for deleteriousness and phenotypic correlation. We observe that the combined impact of INPP5E variants in JBTS and non-syndromic IRD patients does not reveal a clear genotype–phenotype correlation, suggesting the involvement of genetic modifiers. Our study cements the wide phenotypic spectrum of INPP5E disease, adding proof that sequence defects in this gene can lead to early-onset non-syndromic IRD
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Haemogenic Gastruloids Recapitulate Developmental Haematopoiesis and Provide an Ontogeny-Relevant Context to Dissect the Origins of Infant Leukemia
Meeting abstract presented at the 64th ASH Annual Meeting and Exposition, New Orleans, LA, USA, 10-13 Dec 2022..Modelling of developmental hematopoiesis has historically been challenging due to the inability to produce hematopoietic stem cells (HSC) and recapitulate microenvironment interactions ex vivo. Gastruloids are 3D aggregates of embryonic stem (ES) cells which display developmentally-specific spatial and temporal organization that recapitulate gastrulation. We adapted the gastruloid protocol to introduce hematopoietic signalling cues, and generated an in vitro model of embryonic hematopoiesis that sequentially recapitulates the formation of hemogenic endothelium, hematopoietic progenitors, and pre-HSC, over a culture period of 216 hours. Flow cytometry analysis detected the presence of c-Kit+ endothelium at 120h, followed by emergence of CD41+ hematopoietic progenitors at 144h, and the appearance of CD45+ cells from 192h. CD45+ cells were observed in small clusters adjoining endothelium-lined structures, reminiscent of developmental hemogenic-to-endothelial transition and intra-aortic clusters. Single-cell RNA sequencing revealed specification of pre-definitive and definitive waves of embryonic hematopoiesis, aligning 144h-CD41+ cells with erythro-myeloid progenitors (EMP), and late CD45+ with lympho-myeloid progenitors and pre-HSC, altogether supporting the hemogenic gastruloid as a model that is temporally and topographically congruous with the embryo.
The close recapitulation of developmental ontogeny led us to explore hemogenic gastruloids to understand cell and stage-specific susceptibility to forms of Acute Myeloid Leukaemia exclusively observed in infants. The chromosomal translocation t(7;12)(q36;p13), characterized by the ectopic overexpression of the MNX1 gene, is found in up to one third of infant AML cases, but has been challenging to model using conventional strategies, largely due to the inability of MNX1 to transform adult hematopoietic cells. The age-selectivity of t(7;12) has been proposed to reflect a transient developmental window for a target cell of origin absent in adult life, but its nature is yet to be defined. In order to identify the context of MNX1-driven leukemogenesis, we produced hemogenic gastruloids using lentiviral-transduced mouse ES cells in which we overexpressed MNX1 as a proxy of t(7;12). Although MNX1 did not interfere with ES cell pluripotent cultures, it primed incipient hemogenic programmes and promoted hemogenic gastruloid formation. Critically, expression of MNX1 resulted in transformation of gastruloid-derived hematopoietic cells, as assessed by serial colony-forming cell replating, with expansion of a phenotypic myeloid cell, a phenomenon not observed in adult tissues. Detailed analysis of the cellular composition of MNX1-overexpressing hemogenic gastruloids revealed a significant effect in the output of CD41+ and c-Kit+ populations at 144h, but no effect in CD45+ cells at 192-216h, suggesting that the target of MNX1 lies within the EMP stage, an observation supported by single-cell RNA-seq analysis of MNX1 vs control gastruloids. Systematic comparison of the temporal transcriptional profiles of hemogenic gastruloids, MNX1-overexpressing gastruloids, and t(7;12) patients, pinpoints the target cell of MNX1 at the HE-to-EMP transition.
In summary, we propose a novel model of embryonic hematopoiesis capable of capturing developmentally-relevant cellularity and topography of the early hematopoietic microenvironment, with the ability to mechanistically elucidate developmental associations of infant leukemia
Association between a rare SNP in the second intron of human Agouti related protein gene and increased BMI
<p>Abstract</p> <p>Background</p> <p>The agouti related protein (AGRP) is an endogenous antagonist of the melanocortin 4 receptor and is one of the most potent orexigenic factors. The aim of the present study was to assess the genetic variability of <it>AGRP </it>gene and investigate whether the previously reported SNP rs5030980 and the rs11575892, a SNP that so far has not been studied with respect to obesity is associated with increased body mass index (BMI).</p> <p>Methods</p> <p>We determined the complete sequence of the <it>AGRP </it>gene and upstream promoter region in 95 patients with severe obesity (BMI > 35 kg/m<sup>2</sup>). Three polymorphisms were identified: silent mutation c.123G>A (rs34123523) in the second exon, non-synonymous mutation c.199G>A (rs5030980) and c.131-42C>T (rs11575892) located in the second intron. We further screened rs11575892 in a selected group of 1135 and rs5030980 in group of 789 participants from the Genome Database of Latvian Population and Latvian State Research Program Database.</p> <p>Results</p> <p>The CT heterozygotes of rs11575892 had significantly higher mean BMI value (p = 0.027). After adjustment for age, gender and other significant non-genetic factors (presence of diseases), the BMI levels remained significantly higher in carriers of the rs11575892 T allele (p = 0.001). The adjusted mean BMI value of CC genotype was 27.92 ± 1.01 kg/m<sup>2 </sup>(mean, SE) as compared to 30.97 ± 1.03 kg/m<sup>2 </sup>for the CT genotype. No association was found between rs5030980 and BMI.</p> <p>Conclusion</p> <p>This study presents an association of rare allele of <it>AGRP </it>polymorphism in heterozygous state with increased BMI. The possible functional effects of this polymorphism are unclear but may relate to splicing defects.</p
From 2D to 3D: novel nanostructured scaffolds to investigate signalling in reconstructed neuronal networks
To recreate in vitro 3D neuronal circuits will ultimately increase the relevance of results from cultured to whole-brain networks and will promote enabling technologies for neuro-engineering applications. Here we fabricate novel elastomeric scaffolds able to instruct 3D growth of living primary neurons. Such systems allow investigating the emerging activity, in terms of calcium signals, of small clusters of neurons as a function of the interplay between the 2D or 3D architectures and network dynamics. We report the ability of 3D geometry to improve functional organization and synchronization in small neuronal assemblies. We propose a mathematical modelling of network dynamics that supports such a result. Entrapping carbon nanotubes in the scaffolds remarkably boosted synaptic activity, thus allowing for the first time to exploit nanomaterial/cell interfacing in 3D growth support. Our 3D system represents a simple and reliable construct, able to improve the complexity of current tissue culture models
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