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African swine fever virus (ASFV) is a large and complex DNA virus that causes a highly lethal swine disease, against which there is no vaccine available except in Vietnam. ASFV has developed multiple strategies to evade the antiviral innate immune responses. Here, we revealed that the D129L protein (pD129L), a nonstructural protein of ASFV, counteracted the type I interferon (IFN) responses and IFN-stimulated genes (ISGs) expression. Furthermore, we demonstrated that knockdown of D129L by specific small interfering RNAs enhanced the transcription of IFN-β mRNA in the ASFV-infected primary porcine alveolar macrophages (PAMs). Mechanistically, pD129L did not affect the expression of adaptors in the cGAS-STING signaling pathway or the nuclear translocation of IFN regulatory factor 3 (IRF3). Importantly, pD129L specifically bound to the transcriptional coactivators CBP/p300 in the nucleus and inhibited the interaction of IRF3 with CBP/p300, which in turn suppressed the activation of the IFN-β promoter to antagonize the IFN-β induction. More specifically, the HrcA domain of pD129L and the IRF3-binding domain of p300 were mapped crucial for their interaction. Taken together, our findings demonstrate a novel immunoevasion mechanism evolved by ASFV to escape the host antiviral response, which provides a new target for the development of antiviral strategies. IMPORTANCE African swine fever (ASF) is an acute, hemorrhagic, and severe porcine infectious disease caused by African swine fever virus (ASFV). ASF outbreaks severely threaten the global pig industries and result in serious economic losses. No safe and efficacious commercial vaccine is currently available except in Vietnam. To date, large gaps in the knowledge concerning viral biological characteristics and immunoevasion strategies have hindered the ASF vaccine design. In this study, we demonstrate that pD129L negatively regulates the type I interferon (IFN) signaling pathway by interfering with the interaction of the transcriptional coactivator p300 and IRF3, thereby inhibiting the induction of type I IFNs. This study reveals a novel immunoevasion strategy employed by ASFV, shedding new light on the intricate mechanisms for ASFV to evade the host immune responses. [ABSTRACT FROM AUTHOR]

Cyclic adenosine diphosphoribose (cADPR), an endogenous nucleotide derived from nicotinamide adenine dinucleotide (NAD+), mobilizes Ca2+ release from endoplasmic reticulum (ER) via ryanodine receptors (RyRs), yet the bridging protein(s) between cADPR and RyRs remain(s) unknown. Here we synthesized a novel photoaffinity labeling (PAL) cADPR agonist, PAL-cIDPRE, and subsequently applied it to purify its binding proteins in human Jurkat T cells. We identified glyceraldehyde 3-phosphate dehydrogenase (GAPDH) as one of the cADPR binding protein(s), characterized the binding affinity between cADPR and GAPDH in vitro by surface plasmon resonance (SPR) assay, and mapped cADPR's binding sites in GAPDH. We further demonstrated that cADPR induces the transient interaction between GAPDH and RyRs in vivo and that GAPDH knockdown abolished cADPR-induced Ca2+ release. However, GAPDH did not catalyze cADPR into any other known or novel compound(s). In summary, our data clearly indicate that GAPDH is the long-sought-after cADPR binding protein and is required for cADPR-mediated Ca2+ mobilization from ER via RyRs. [ABSTRACT FROM AUTHOR]

The H240R protein (pH240R), encoded by the H240R gene of African swine fever virus (ASFV), is a 241-amino-acid capsid protein. We previously showed that the deletion of H240R from the ASFV genome, creating ASFV-ΔH240R, resulted in an approximately 2-log decrease in infectious virus production compared with the wild-type ASFV strain (ASFV-WT), and ASFV-ΔH240R induced higher interleukin 1β (IL-1β) production in porcine alveolar macrophages (PAMs) than did ASFV-WT, but the underlying mechanism remains to be elucidated. Here, we demonstrate that the activation of the NF-κB signaling and NLRP3 inflammasome was markedly induced in PAMs upon ASFV-ΔH240R infection compared with ASFV-WT. Moreover, pH240R inhibited NF-κB activation by interacting with NEMO and promoting the autophagymediated lysosomal degradation of NEMO, resulting in reduced pro-IL-1β transcription. Strikingly, NLRP3 deficiency in PAMs inhibited the ASFV-DH240R-induced IL-1β secretion and caspase 1 activation, indicating an essential role of NLRP3 inflammasome activation during ASFV-ΔH240R replication. Mechanistically, pH240R interacted with NLRP3 to inhibit its oligomerization, leading to decreased IL-1β production. Furthermore, the inhibition of the NF-κB signaling and NLRP3 inflammasome activation promoted ASFV-ΔH240R replication in PAMs. Taken together, the results of this study reveal an antagonistic mechanism by which pH240R suppresses the host immune response by manipulating activation of the NF-κB signaling and NLRP3 inflammasome, which might guide the rational design of live attenuated vaccines or therapeutic strategies against ASF in the future. [ABSTRACT FROM AUTHOR]

Critical path method delay analysis techniques are widely applied in the construction industry, with the windows method being regarded as technologically advantageous. The approach looks at different schedule snapshots (windows) throughout the project and analyzes the contractor versus owner responsibility for delaying the critical paths. Accordingly, decisions regarding time and/or cost compensation could be made. While the technique is beneficial, it is computationally intensive and produces different results with different window sizes. Commercial software provide little support in this regard and the analysis is usually done manually. In this paper, a modified windows approach is introduced with computerized daily analysis of delays so that accurate and repeatable results are produced. The new approach is coupled with a new representation of progress information and is readily usable by professionals and researchers to evaluate project delays. Details of the daily analysis are introduced along with two case studies that demonstrate its advantages over the traditional windows approach. A downloadable version is made available for experimental use by researchers and professionals. [ABSTRACT FROM AUTHOR]

African swine fever virus (ASFV) is a complex nucleocytoplasmic large DNA virus that causes African swine fever, a lethal hemorrhagic disease that currently threatens the pig industry. Recent studies have identified the viral structural proteins of infectious ASFV particles. However, the functional roles of several ASFV structural proteins remain largely unknown. Here, we characterized the function of the ASFV structural protein H240R (pH240R) in virus morphogenesis. pH240R was identified as a capsid protein by using immunoelectron microscopy and interacted with the major capsid protein p72 by pulldown assays. Using a recombinant ASFV, ASFV-DH240R, with the H240R gene deleted from the wild-type ASFV (ASFV-WT) genome, we revealed that the infectious progeny virus titers were reduced by approximately 2.0 logs compared with those of ASFV-WT. Furthermore, we demonstrated that the growth defect was due to the generation of noninfectious particles with a higher particle-to-infectious titer ratio in ASFV-DH240R-infected primary porcine alveolar macrophages (PAMs) than in those infected with ASFV-WT. Importantly, we found that pH240R did not affect virus-cell binding, endocytosis, or egress but did affect ASFV assembly; noninfectious virions containing large aberrant tubular and bilobulate structures comprised nearly 98% of all virions observed in ASFV-DH240R-infected PAMs by electron microscopy. Notably, we demonstrated that ASFV-DH240R infection induced high-level expression of inflammatory cytokines in PAMs. Collectively, we show for the first time that pH240R is essential for ASFV icosahedral capsid formation and infectious particle production. Also, these results highlight the importance of pH240R in ASFV morphogenesis and provide a novel target for the development of ASF vaccines and antivirals. [ABSTRACT FROM AUTHOR]

The sustaining environments hypothesis theorizes that the lasting effects of PreK programs are contingent on the quality of the subsequent learning environment in early elementary school. The current study tests this theory by leveraging data from students (N = 462) who did and did not enroll in the Boston Public Schools (BPS) prekindergarten (PreK) program as well as features of their kindergarten instruction measured at the child- and classroom-levels using surveys and observations. Taken together, findings revealed limited evidence for the sustaining environments hypothesis. The bulk of the results were null, indicating that in general, associations between enrollment in BPS PreK and language, literacy, and math skills through the spring of kindergarten did not vary by kindergarten instructional experiences. When examining distinct types of instructional experiences, there were some inklings that child-level observational measures of kindergarten learning experiences--particularly those capturing constrained versus unconstrained instruction--were more predictive of PreK persistence than observed global classroom quality measures or survey-based measures of advanced instruction. However, these associations were not always specific to outcomes matching the content delivered during this instruction (math vs. literacy), consistent with the possibility of either cross-domain effects or that instructional variables are proxies for more general instruction;il practices. Findings for future research and theory are discussed. [ABSTRACT FROM AUTHOR]

African swine fever virus (ASFV) is the causative agent of African swine fever, a highly contagious and usually fatal disease in pigs. The pathogenesis of ASFV infection has not been clearly elucidated. Here, we used single-cell RNA-sequencing technology to survey the transcriptomic landscape of ASFV-infected primary porcine alveolar macrophages. The temporal dynamic analysis of viral genes revealed increased expression of viral transmembrane genes. Molecular characteristics in the ASFV-exposed cells exhibited the activation of antiviral signaling pathways with increased expression levels of interferon-stimulated genes and inflammatory- and cytokine-related genes. By comparing infected cells with unexposed cells, we showed that the unfolded protein response (UPR) pathway was activated in low viral load cells, while the expression level of UPRrelated genes in high viral load cells was less than that in unexposed cells. Cells infected with various viral loads showed signature transcriptomic changes at the median progression of infection. Within the infected cells, differential expression analysis and coregulated virus–host analysis both demonstrated that ASFV promoted metabolic pathways but inhibited interferon and UPR signaling, implying the regulation pathway of viral replication in host cells. Furthermore, our results revealed that the cell apoptosis pathway was activated upon ASFV infection. Mechanistically, the production of tumor necrosis factor alpha (TNF-α) induced by ASFV infection is necessary for cell apoptosis, highlighting the importance of TNF-α in ASFV pathogenesis. Collectively, the data provide insights into the comprehensive host responses and complex virus–host interactions during ASFV infection, which may instruct future research on antiviral strategies. [ABSTRACT FROM AUTHOR]

Daily recording of the actions done by all parties on a construction site is necessary, not only for confirming that work is done according to specifications, but also for analyzing any claims for additional time/cost. Site records, however, are often incomplete and inaccurate, and commercial scheduling software provides little support in this regard. In this paper, a simplified approach for site-data recording and constructing “as-built” schedules is introduced through the use of intelligent bar charts. The proposed bar chart guides the user through progress reporting by observing any conflict with the planned logic of the work. It automatically recognizes the occurrence of delays and asks the user to record the responsible party and the reasons. Based on percent completes and recorded delays, the bar chart recognizes the progress status of activities as being slow, suspended, or accelerated. The paper starts with a description of the types of data that need to be recorded on site. It then provides a description of the automated guidance mechanism of the proposed bar chart, along with details on schedule integration and applicability for claim analysis. [ABSTRACT FROM AUTHOR]

Nicotinamide adenine dinucleotide (NAD), one of the most important coenzymes in the cells, is a substrate of the signaling enzyme CD38, by which NAD is converted to a second messenger, cyclic ADP-ribose, which releases calcium from intracellular calcium stores. Starting with 2'-deoxy-2'-fluoroarabinosyl-β-nicotinamide adenine dinucleotide (ara-F NAD), a series of NAD analogues were synthesized and their activities to inhibit CD38 NAD glycohydrolase (NADase) were evaluated. The adenosine-modified analogues showed potent inhibitory activities, among which 2'-deoxy-2'-fluoroarabinosyl-β-nicotinamide guanine dinucleotide (ara-F NGD) was the most effective one. The structure-activity relationship of NAD analogues was also discussed. [ABSTRACT FROM AUTHOR]

A novel trifluoromethylated analogue of cADPR, 8-CF3-cIDPDE (5) was designed and synthesized via construction of N¹,N9-disubstituted hypoxanthine, trifluoromethylation and intramolecular condensation. A series of acyclic analogues of cADPR were also designed and synthesized. These compounds could be useful molecules for studying the structure-activity relationship of cADPR analogues and exploring the cADPR/RyR Ca2+ signalling system. [ABSTRACT FROM AUTHOR]

This paper proposes a system, a meta-reasoner, to diagnose other systems. This system, called DSKE, performs its diagnosis based upon the knowledge of the structure of the system under diagnosis and based upon previous diagnostic experiences with that system. Since DSKE is based upon first order logic, it has strong deductive powers. Given adequate information, it can diagnose problems quite impressively. Contrary to probabilistic and fuzzy logic approaches, our system is not based upon data which may or may not be available, and which may or may not be reliable. Further, our system makes use of available knowledge. Contrary to model based diagnosis systems, our system can handle uncertainty and incomplete knowledge. The algorithm we provide yields a minimal diagnosis which covers all the abnormal behaviors detected. This paper provides a detailed description of DSKE. The inner workings of the system are carefully and comprehensively analyzed. Examples illustrate the advantages of our system, and demonstrate its use. [ABSTRACT FROM AUTHOR]