Heat Transfer of Helix Energy Pile: Part 2—Novel Truncated Cone Helix Energy Pile

Owing to the fact that severe thermal interferences exist in the radial and generatrix directions of the traditional cylinder helix energy pile due to the limited thermal heat capacity of the pile and small ratio between coil pitch and radius of pile, therefore, a novel truncated cone helix energy pile (CoHEP) is presented to weaken the thermal interferences and improve the heat transfer efficiency. Further, both the analytical solution model and numerical solution model for CoHEP are built to discuss the dynamic characteristics of thermal interferences and heat transfer performance. The results indicate that the thermal interference of CoHEP is dynamic. The thermal interference in the upper part of the CoHEP is much smaller than the traditional CyHEP. And in general the heat flux per unit pipe length of the novel CoHEP is larger than that of the traditional CyHEP. Heat flux per unit pipe length of the CoHEP increases linearly with inlet water temperature. For the same inlet water temperature, the thermal short circuit is serious at the bottom of the CoHEP, and it’s weak in the upper part of CoHEP. Also it’s obvious that as the inlet water temperature increases, the thermal short circuit becomes more serious

Heat Transfer of Helix Energy Pile: Part 1: Traditional Cylinder Helix Energy Pile

Helix energy pile (HEP) is a new popular ground heat exchanger that has the advantages of large heat exchange rate and low initial cost. As for the traditional helix energy pile, the tube is wound on the cylindrical wall, which is called the cylinder helix energy pile (CyHEP). Further, both analytical solution model and numerical solution model for CyHEP are built to discuss the dynamic characteristics of thermal interferences and heat transfer performance. The results indicate that four heat exchange stages for the spiral pile geothermal heat exchanger along the fluid flow direction are revealed: inlet heat exchange stage, grout thermal short-circuiting stage, small temperature difference stage and outlet heat exchange stage. Each stage has corresponding heat transfer characteristics, and reducing the length of small temperature difference stage and increasing the other stages would enhance the heat exchange of spiral geothermal ground heat exchanger. As the pile diameter increases, the heat transfer per unit tube length decreases, and the heat exchange per unit pile depth increases. As the pile depth increases, the heat transfer per unit tube length and the heat exchange per unit pile depth are reduced. And as the pitch increases, the heat transfer per unit tube length increases, and the heat exchange per unit pile depth decreases

Comparative functional genomic study of substrate specificity evolution of the SABATH family of methyltransferases in plants

Background The plant SABATH protein family is composed of a group of related small molecule methyltransferases (MTs) that catalyze the S-adenosyl-L-methionine dependent methylation of a variety of plant small molecular weight metabolites encompassing widely divergent structures. Some of these substrates are important plant hormones and signaling molecules, such as indole-3-acetic acid (IAA), jasmonic acid (JA) and salicylic acid (SA). Methylating these compounds may have important impacts on plant growth and development. In the previous paper, we presented Indole-3-acetic acid (IAA) methyltransferase (IAMT) as an evolutionarily ancient member of the SABATH family in higher plants. Whether the IAMT exists in less evolutionarily advanced plants is still unknown. Materials and methods To further understand the evolution of the SABATH family in land plants, we undertook an integrated functional genomic approach to identify and characterize SABATH genes in a lower plant moss (Physcomitrella patens). Four putative moss SABATH genes were identified using bioinformatics tools. Results and conclusion Enzymatic assay displayed none of them had IAMT activity, suggesting that IAMT might be evolved after the divergence of lower and higher plants. However, one of them, PpSABATH1, showed methyltransferase activity with a number of compounds containing sulhydryl or selenohydryl groups. Tobacco plants overexpressing the PpSABATH1 gene under the control of CaMV35S promoter exhibited an enhanced tolerance to thiobenzoic acid. Together with these results, we hypothesize that IAMT, the evolutionarily ancient member of the SABATH family in higher plants, evolved from a sulfur methyltransferase

Comparative functional genomic study of substrate specificity evolution of the SABATH family of methyltransferases in plants

Background The plant SABATH protein family is composed of a group of related small molecule methyltransferases (MTs) that catalyze the S-adenosyl-L-methionine dependent methylation of a variety of plant small molecular weight metabolites encompassing widely divergent structures. Some of these substrates are important plant hormones and signaling molecules, such as indole-3-acetic acid (IAA), jasmonic acid (JA) and salicylic acid (SA). Methylating these compounds may have important impacts on plant growth and development. In the previous paper, we presented Indole-3-acetic acid (IAA) methyltransferase (IAMT) as an evolutionarily ancient member of the SABATH family in higher plants. Whether the IAMT exists in less evolutionarily advanced plants is still unknown. Materials and methods To further understand the evolution of the SABATH family in land plants, we undertook an integrated functional genomic approach to identify and characterize SABATH genes in a lower plant moss (Physcomitrella patens). Four putative moss SABATH genes were identified using bioinformatics tools. Results and conclusion Enzymatic assay displayed none of them had IAMT activity, suggesting that IAMT might be evolved after the divergence of lower and higher plants. However, one of them, PpSABATH1, showed methyltransferase activity with a number of compounds containing sulhydryl or selenohydryl groups. Tobacco plants overexpressing the PpSABATH1 gene under the control of CaMV35S promoter exhibited an enhanced tolerance to thiobenzoic acid. Together with these results, we hypothesize that IAMT, the evolutionarily ancient member of the SABATH family in higher plants, evolved from a sulfur methyltransferase

Chloroplast genome resources and molecular markers differentiate rubber dandelion species from weedy relatives

Rubisco large subunit genes (rbcL) from the Asteraceae. (DOCX 29 kb

Molecular identification and characterization of two rubber dandelion amalgaviruses

The Amalgaviridae family is composed of persistent viruses that share the genome architecture of Totiviridae and gene evolutionary resemblance to Partitiviridae. A single Amalgavirus genus has been assigned to this family, presenting only four recognized species, corresponding to plant infecting viruses with dsRNA monopartite genomes of ca. 3.4 kb. Here, we present the genomic identification and characterization of two novel viruses detected in rubber dandelion (Taraxacum kok-saghyz). The sequenced isolates presented genomes of 3,409 and 3,413 nt long, including two partially overlapping ORFs encoding a putative coat protein and an RNA-dependent RNA polymerase (RdRP). Phylogenetic insights based on the detected virus sequences suggest them to be members of two new species within the Amalgavirus genus. Multiple independent RNAseq data suggest that the identified viruses have a dynamic distribution and low relative RNA levels in infected plants. Virus presence was not associated with any apparent symptoms on the plant hosts. We propose the names rubber dandelion latent virus 1 & 2 to the detected amalgaviruses; the first viruses to be associated to this emergent and sustainable natural rubber crop.Fil: Debat, Humberto Julio. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patología Vegetal; ArgentinaFil: Zinan Luo. Ohio State University. Department of Horticulture and Crop Science; Estados UnidosFil: Iaffaldano, Brian J. Ohio State University. Department of Horticulture and Crop Science; Estados UnidosFil: Xiaofeng Zhuang. Ohio State University. Department of Horticulture and Crop Science; Estados UnidosFil: Cornish, Katrina. Ohio State University. Department of Horticulture and Crop Science; Estados Unido

Quasiatomic orbitals for ab initio tight-binding analysis

Wave functions obtained from plane-wave density-functional theory (DFT) calculations using norm-conserving pseudopotential, ultrasoft pseudopotential, or projector augmented-wave method are efficiently and robustly transformed into a set of spatially localized nonorthogonal quasiatomic orbitals (QOs) with pseudoangular momentum quantum numbers. We demonstrate that these minimal-basis orbitals can exactly reproduce all the electronic structure information below an energy threshold represented in the form of environment-dependent tight-binding Hamiltonian and overlap matrices. Band structure, density of states, and the Fermi surface are calculated from this real-space tight-binding representation for various extended systems (Si, SiC, Fe, and Mo) and compared with plane-wave DFT results. The Mulliken charge and bond order analyses are performed under QO basis set, which satisfy sum rules. The present work validates the general applicability of Slater and Koster\u27s scheme of linear combinations of atomic orbitals and points to future ab initio tight-binding parametrizations and linear-scaling DFT development

Prodrug design, synthesis and pharmacokinetic evaluation of (3′R, 4′R)-3-hydroxymethyl-4-methyl-3′, 4′-di-O-(S)-camphanoyl-(+)-cis-khellactone

3-Hydroxymethyl-4-methyl-DCK (3, HMDCK) was discovered previously as a potent HIV non-nucleoside reverse transcriptase inhibitor (NNRTIs) (EC50: 0.004 μM, TI: 6225) with a novel mechanism of action. It exerts anti-HIV activity by inhibiting the production of HIV-1 double-stranded viral DNA from a single-stranded DNA intermediate, rather than blocking the generation of single-stranded DNA from a RNA template, which is the mechanism of action of current HIV-1 RT inhibitors. However, the insufficient metabolic stability of 3 limits its further clinical development. In the current study, a series of ester prodrugs of 3 was designed and synthesized to explore the new drug candidates as NNRTIs. The l-alanine ester prodrug 10 exhibited desirable pharmacokinetic properties in vitro and in vivo and showed improved oral bioavailability of 26% in rat, and would be a potential clinical candidate as a new anti-AIDS drug

Machine Learning for Prediction of Sudden Cardiac Death in Heart Failure Patients With Low Left Ventricular Ejection Fraction: Study Protocol for a Retrospective Multicentre Registry in China

Introduction: Left ventricular ejection fraction (LVEF) ≤35%, as current significant implantable cardioverter-defibrillator (ICD) indication for primary prevention of sudden cardiac death (SCD) in heart failure (HF) patients, has been widely recognised to be inefficient. Improvement of patient selection for low LVEF (≤35%) is needed to optimise deployment of ICD. Most of the existing prediction models are not appropriate to identify ICD candidates at high risk of SCD in HF patients with low LVEF. Compared with traditional statistical analysis, machine learning (ML) can employ computer algorithms to identify patterns in large datasets, analyse rules automatically and build both linear and non-linear models in order to make data-driven predictions. This study is aimed to develop and validate new models using ML to improve the prediction of SCD in HF patients with low LVEF. Methods and analysis: We will conduct a retroprospective, multicentre, observational registry of Chinese HF patients with low LVEF. The HF patients with LVEF ≤35% after optimised medication at least 3 months will be enrolled in this study. The primary endpoints are all-cause death and SCD. The secondary endpoints are malignant arrhythmia, sudden cardiac arrest, cardiopulmonary resuscitation and rehospitalisation due to HF. The baseline demographic, clinical, biological, electrophysiological, social and psychological variables will be collected. Both ML and traditional multivariable Cox proportional hazards regression models will be developed and compared in the prediction of SCD. Moreover, the ML model will be validated in a prospective study. Ethics and dissemination: The study protocol has been approved by the Ethics Committee of the First Affiliated Hospital of Nanjing Medical University (2017-SR-06). All results of this study will be published in international peer-reviewed journals and presented at relevant conferences

Development of a CT image analysis-based scoring system to differentiate gastric schwannomas from gastrointestinal stromal tumors

PurposeTo develop a point-based scoring system (PSS) based on contrast-enhanced computed tomography (CT) qualitative and quantitative features to differentiate gastric schwannomas (GSs) from gastrointestinal stromal tumors (GISTs).MethodsThis retrospective study included 51 consecutive GS patients and 147 GIST patients. Clinical and CT features of the tumors were collected and compared. Univariate and multivariate logistic regression analyses using the stepwise forward method were used to determine the risk factors for GSs and create a PSS. Area under the receiver operating characteristic curve (AUC) analysis was performed to evaluate the diagnostic efficiency of PSS.ResultsThe CT attenuation value of tumors in venous phase images, tumor-to-spleen ratio in venous phase images, tumor location, growth pattern, and tumor surface ulceration were identified as predictors for GSs and were assigned scores based on the PSS. Within the PSS, GS prediction probability ranged from 0.60% to 100% and increased as the total risk scores increased. The AUC of PSS in differentiating GSs from GISTs was 0.915 (95% CI: 0.874–0.957) with a total cutoff score of 3.0, accuracy of 0.848, sensitivity of 0.843, and specificity of 0.850.ConclusionsThe PSS of both qualitative and quantitative CT features can provide an easy tool for radiologists to successfully differentiate GS from GIST prior to surgery