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Allogeneic haematopoietic cell transplantation (HCT) replaces the stem cells responsible for blood production with those harvested from a donor, and is received by 40,000 patients worldwide each year. To quantify dynamics of long-term stem cell engraftment, we sequenced whole genomes of 2,824 single-cell-derived haematopoietic colonies from blood samples of 10 donor-recipient pairs taken 9-31 years after HLA-matched sibling HCT. With younger donors, 10,000–50,000 stem cells had engrafted and were still contributing to haematopoiesis at time of sampling, but estimates were 10-fold lower with older donors. Engrafted stem cells made multilineage contributions to myeloid, B-lymphoid and T-lymphoid populations, although individual clones often showed biases towards one or other mature cell type. Recipients had lower clonal diversity than matched donors, equivalent to ~10-15 years of additional ageing, arising from up to 25-fold greater expansion of stem cell clones. An HCT-related population bottleneck alone could not explain these differences: instead, phylogenetic trees evinced two distinct modes of HCT-specific selection. In ‘pruning selection’, cell divisions underpinning recipient-enriched clonal expansions had occurred in the donor, preceding transplant – their selective advantage derived from preferential mobilisation, harvest, survival ex vivo or initial homing. In ‘growth selection’, cell divisions underpinning clonal expansion occurred through proliferative advantage in the recipient’s marrow after homing – clones with multiple driver mutations especially demonstrated this pattern. Uprooting stem cells from their native environment and transplanting them to foreign soil exaggerates selective pressures, distorting and accelerating the loss of clonal diversity compared to the unperturbed haematopoiesis of donors.

Funder: Max Williamson Fund, Germ cell tumours (GCTs) are a collection of benign and malignant neoplasms derived from primordial germ cells. They are uniquely able to recapitulate embryonic and extraembryonic tissues, which carries prognostic and therapeutic significance. The developmental pathways underpinning GCT initiation and histogenesis are incompletely understood. Here, we study the relationship of histogenesis and clonal diversification in GCTs by analysing the genomes and transcriptomes of 547 microdissected histological units. We find no correlation between genomic and histological heterogeneity. However, we identify unifying features including the retention of fetal developmental transcripts across tissues, expression changes on chromosome 12p, and a conserved somatic evolutionary sequence of whole genome duplication followed by clonal diversification. While this pattern is preserved across all GCTs, the developmental timing of the duplication varies between prepubertal and postpubertal cases. In addition, tumours of younger children exhibit distinct substitution signatures which may lend themselves as potential biomarkers for risk stratification. Our findings portray the extensive diversification of GCT tissues and genetic subclones as randomly distributed, while identifying overarching transcriptional and genomic features.

Previous studies studying mis-splicing mutations were based on exome data and thus our current knowledge is largely limited to exons and the canonical splice sites. To comprehensively characterise intronic mis-splicing mutations, we analysed 1134 pan-cancer whole genomes and transcriptomes together with 3022 normal control samples. The ratio-based splicing analysis resulted in 678 somatic intronic mutations, with 46% residing in deep introns. Among the 309 deep intronic single nucleotide variants, 245 altered core splicing codes, with 38% activating cryptic splice sites, 12% activating cryptic polypyrimidine tracts, and 36% and 12% disrupting authentic polypyrimidine tracts and branchpoints, respectively. All the intronic cryptic splice sites were created at pre-existing GT/AG dinucleotides or by GC-to-GT conversion. Notably, 85 deep intronic mutations indicated gain of splicing enhancers or loss of splicing silencers. We found that 64 tumour suppressors were affected by intronic mutations and blood cancers showed higher proportion of deep intronic mutations. In particular, a telomere maintenance gene, POT1, was recurrently mis-spliced by deep intronic mutations in blood cancers. We validated a pseudoexon activation involving a splicing silencer in POT1 by CRISPR/Cas9. Our results shed light on previously unappreciated mechanisms by which noncoding mutations acting on splicing codes in deep introns contribute to tumourigenesis.

Cellular DNA damage caused by reactive oxygen species is repaired by the base excision repair (BER) pathway which includes the DNA glycosylase MUTYH. Inherited biallelic MUTYH mutations cause predisposition to colorectal adenomas and carcinoma. However, the mechanistic progression from germline MUTYH mutations to MUTYH-Associated Polyposis (MAP) is incompletely understood. Here, we sequenced normal tissue DNAs from 10 individuals with MAP. Somatic base substitution mutation rates in intestinal epithelial cells were elevated 2 to 5-fold in all individuals, except for one showing a 33-fold increase, and were also increased in other tissues. The increased mutation burdens were of multiple mutational signatures characterised by C>A changes. Different mutation rates and signatures between individuals were likely due to different MUTYH mutations or additional inherited mutations in other BER pathway genes. The elevated base substitution rate in normal cells likely accounts for the predisposition to neoplasia in MAP. Despite ubiquitously elevated mutation rates, individuals with MAP do not display overt evidence of premature ageing. Thus, accumulation of somatic mutations may not be sufficient to cause the global organismal functional decline of ageing.Summary

Today, IoT devices are flooding, and traffic is increasing rapidly. The Internet of Things creates a variety of added value through connections between devices, while many devices are easily targeted by attackers due to security vulnerabilities. In the IoT environment, security diagnosis has problems such as having to provide different solutions for different types of devices in network situations where various types of devices are interlocked, personal leakage of security solutions themselves, and high cost, etc. To avoid such problems, a TCP-based active scan was presented. However, the TCP-based active scan has limitations that it is difficult to be applied to real-time systems due to long detection times. To complement this, this study uses UDP-based approaches. Specifically, a lightweight active scan algorithm that effectively identifies devices using UPnP protocols (SSDP, MDNS, and MBNS) that are most commonly used by manufacturers is proposed. The experimental results of this study have shown that devices can be distinguished by more than twice the true positive and recall at an average time of 1524 times faster than Nmap, which has a firm position in the field.

Background It is crucial to unravel molecular determinants of responses to immune checkpoint blockade (ICB) therapy because only a small subset of advanced non-small cell lung cancer (NSCLC) patients responds to ICB therapy. Previous studies were concentrated on genomic and transcriptomic markers (e.g., mutation burden and immune gene expression). However, these markers are not sufficient to accurately predict a response to ICB therapy. Results Here, we analyzed DNA methylomes of 141 advanced NSCLC samples subjected to ICB therapy (i.e., anti-programmed death-1) from two independent cohorts (60 and 81 patients from our and IDIBELL cohorts). Integrative analysis of patients with matched transcriptome data in our cohort (n = 28) at pathway level revealed significant overlaps between promoter hypermethylation and transcriptional repression in nonresponders relative to responders. Fifteen immune-related pathways, including interferon signaling, were identified to be enriched for both hypermethylation and repression. We built a reliable prognostic risk model based on eight genes using LASSO model and successfully validated the model in independent cohorts. Furthermore, we found 30 survival-associated molecular interaction networks, in which two or three hypermethylated genes showed significant mutual exclusion across nonresponders. Conclusions Our study demonstrates that methylation patterns can provide insight into molecular determinants underlying the clinical benefit of ICB therapy.

L1 retrotransposons can pose a threat to genome integrity. The host has evolved to restrict L1 replication. However, mechanisms underlying L1 propagation out of the host surveillance remains unclear. Here, we propose a novel survival strategy of L1, which exploits RNA m6A modification. We discover that m6A ‘writer’ METTL3 facilitates L1 retrotransposition, whereas m6A ‘eraser’ ALKBH5 suppresses it. The essential m6A cluster that is located on L1 5′ UTR serves as a docking site for eukaryotic initiation factor 3 (eIF3), enhances translational efficiency and promotes the formation of L1 ribonucleoprotein. Furthermore, through the comparative analysis of human- and primate-specific L1 lineages, we find that the most functional m6A motif-containing L1s have been positively selected and became a distinctive feature of evolutionarily young L1s. Thus, our findings demonstrate that L1 retrotransposons hijack RNA m6A modification system for its successful replication.

Neoantigen burden is regarded as a fundamental determinant of response to immunotherapy. However, its predictive value remains in question because some tumours with high neoantigen load show resistance. Here, we investigate our patient cohort together with a public cohort by our algorithms for the modelling of peptide-MHC binding and inter-cohort genomic prediction of therapeutic resistance. We first attempt to predict MHC-binding peptides at high accuracy with convolutional neural networks. Our prediction outperforms previous methods in > 70% of test cases. We then develop a classifier that can predict resistance from functional mutations. The predictive genes are involved in immune response and EGFR signalling, whereas their mutation patterns reflect positive selection. When integrated with our neoantigen profiling, these anti-immunogenic mutations reveal higher predictive power than known resistance factors. Our results suggest that the clinical benefit of immunotherapy can be determined by neoantigens that induce immunity and functional mutations that facilitate immune evasion., Predicting response to cancer immunotherapy is still a challenge. Here, the authors show that their method of predicting MHC-binding peptides, combined with profiling anti-immunogenic mutations, can better predict the clinical benefit of immunotherapy.

The haematopoietic system manifests several age-associated phenotypes including anaemia; loss of regenerative capacity, especially in the face of insults such as infection, chemotherapy or blood loss; and increased risk of clonal haematopoiesis and blood cancers. The cellular alterations that underpin these age-related phenotypes, which typically manifest in individuals aged over 70, remain elusive. We aimed to investigate whether changes in HSC population structure with age might underlie any aspects of haematopoietic system ageing. We sequenced 3579 genomes from single-cell-derived colonies of haematopoietic stem cell/multipotent progenitors (HSC/MPPs) from 10 haematologically normal subjects aged 0-81 years. HSC/MPPs accumulated 17 somatic mutations/year after birth with no increased rate of mutation accumulation in the elderly. HSC/MPP telomere length declined by 30 bp/yr. In cord blood and adults aged To interrogate changes in HSC population structure with age, we used the pattern of unique and shared mutations between the sampled cells from each individual to reconstruct their phylogenetic relationships. The frequency of branch-points (known as coalescences) in phylogenetic trees in a neutrally evolving, well-mixed population of somatic cells is primarily determined by the product of population size and time between symmetric self-renewal cell divisions (Nt). Smaller populations and more frequent symmetric divisions both increase the density of coalescences. Specific clones can come to dominate either through neutral drift or positive selection. We found that haematopoiesis in adults aged 75 showed profoundly decreased clonal diversity. In each elderly subject, 30-60% of haematopoiesis was accounted for by 12-18 independent clones, each contributing 1-34% of blood production. Most clones had begun their expansion before age 40, but only 22% had known driver mutations. We used the ratio of non-synonymous to synonymous mutations (dN/dS) to identify any excess of non-synonymous (driver) mutations in the dataset. This genome-wide selection analysis estimated that 1/34 to 1/12 non-synonymous mutations were drivers, occurring at a constant rate throughout life, such that the set of 300 - 400 HSC/MPPs sampled from each adult individual harboured around 100 driver mutations, over 10-fold higher than the number of known drivers we could identify. Novel drivers affected a wider pool of genes than identified in blood cancers. The genes DNMT3A, ZNF318 and HIST2H3D were identified as being under significant positive selection in HSC/MPPs, despite ZNF318 and HIST2H3D not being enriched in the setting of myeloid malignancies. Loss of Y chromosome conferred selective benefits on HSC/MPPs in males. Simulations from a simple model of haematopoiesis, with constant HSC population size and constant acquisition of driver mutations conferring moderate fitness benefits, entirely explained the abrupt change in clonal structure observed in the elderly, which could not be explained by neutral models incorporating drift alone. Our data supports the view that dramatically decreased clonal diversity is a universal feature of haematopoiesis in aged humans, underpinned by pervasive positive selection acting on many more genes than currently known. By old age the majority of HSCs harbour at least one driver mutation. With such ubiquity of driver mutations, selected purely for their competitive advantage within the stem cell compartment, and with the wholesale rewiring of cellular pathways they induce, it is feasible that they may contribute to age-related phenotypes beyond the increased risk of blood cancer. Disclosures Spencer: Wugen, Inc.: Consultancy, Other: Stock Options. Vassiliou: Kymab Ltd: Divested equity in a private or publicly-traded company in the past 24 months; STRM.BIO: Consultancy; Astrazeneca: Consultancy. Kent: STRM.bio: Research Funding. Campbell: Mu Genomics: Current holder of individual stocks in a privately-held company, Membership on an entity's Board of Directors or advisory committees.

Impregnated amine adsorbents show high CO 2 adsorption capacity, however, leaching out and evaporation of amines, urea formation problem was existed. These problems are critical to the long term operation of CO 2 capture, and related to the physical and chemical stability of amines at regeneration temperature. In order to overcome limitations, crosslinking method between amine groups was introduced. Crosslinkers having two amine reactive groups, such as acid, aldehyde were used to prepare crosslinked polyethyleneimine (PEI)-impregnated adsorbents. The viscosities of the crosslinked PEIs were increased compared to the pristine PEI. The structure and the amine ratio of the crosslinked PEIs were investigated by 13 C NMR analysis. Simulated TSA cyclic operation was conducted by thermogravimetric analyzer (TGA), and all of crosslinked PEI-impregnated adsorbents were exhibited lower CO 2 capacity compared to PEI-impregnated adsorbents, but less urea formation was observed.

Ocular marginal zone lymphoma is a common type of low-grade B-cell lymphoma. To investigate the genomic changes that occur in ocular marginal zone lymphoma, we analyzed 10 cases of ocular marginal zone lymphoma using whole-genome and RNA sequencing and an additional 38 cases using targeted sequencing. Major genetic alterations affecting genes involved in nuclear factor (NF)-κB pathway activation (60%), chromatin modification and transcriptional regulation (44%), and B-cell differentiation (23%) were identified. In whole-genome sequencing, the 6q23.3 region containing TNFAIP3 was deleted in 5 samples (50%). In addition, 5 structural variation breakpoints in the first intron of IL20RA located in the 6q23.3 region was found in 3 samples (30%). In targeted sequencing, a disruptive mutation of TNFAIP3 was the most common alteration (54%), followed by mutations of TBL1XR1 (18%), cAMP response element binding proteins (CREBBP) (17%) and KMT2D (6%). All TBL1XR1 mutations were located within the WD40 domain, and TBL1XR1 mutants transfected into 293T cells increased TBL1XR1 binding with nuclear receptor corepressor (NCoR), leading to increased degradation of NCoR and the activation of NF-κB and JUN target genes. This study confirms genes involving in the activation of the NF-kB signaling pathway is the major driver in the oncogenesis of ocular MZL.

Summary Inflammatory bowel disease (IBD) is a chronic inflammatory disease associated with increased risk of gastrointestinal cancers. We whole-genome sequenced 446 colonic crypts from 46 IBD patients and compared these to 412 crypts from 41 non-IBD controls from our previous publication on the mutation landscape of the normal colon. The average mutation rate of affected colonic epithelial cells is 2.4-fold that of healthy colon, and this increase is mostly driven by acceleration of mutational processes ubiquitously observed in normal colon. In contrast to the normal colon, where clonal expansions outside the confines of the crypt are rare, we observed widespread millimeter-scale clonal expansions. We discovered non-synonymous mutations in ARID1A, FBXW7, PIGR, ZC3H12A, and genes in the interleukin 17 and Toll-like receptor pathways, under positive selection in IBD. These results suggest distinct selection mechanisms in the colitis-affected colon and that somatic mutations potentially play a causal role in IBD pathogenesis., Graphical Abstract, Highlights • IBD-affected colons accrue substitutions and indels 2.4 and 7 times faster than normal • 17 signatures of mutational processes, including treatment • Millimeter-scale clonal expansions late in molecular time • Distinct mechanisms of positive selection of mutations in immune-related genes, Whole-genome sequencing of inflammatory bowel disease patient samples allows insight into mutational burdens and processes associated with disease, including putative driver mutations positively selected in the diseased colon.

Amine-based silica sorbents for CO 2 capture prepared by an impregnation method generally show high adsorption capacity, but physical and chemical degradation for long-term operation are critical problems such as leaching and evaporation of amines, and urea formation, respectively. A strategy to form crosslinks between the impregnated amines was introduced to prevent these problems. Crosslinkers with two amine-reactive groups such as epoxy and halide were used to prepare crosslinked polyethyleneimine (PEI)-impregnated sorbents. A viscosity increase was observed in all crosslinked PEIs. The structure and the amine ratio of the crosslinked PEIs were investigated by 13 C NMR analysis. The highest reaction selectivity to primary amines and the formation of hydroxyl groups were observed for 1,3-butadienediepoxide (BDDE). In addition, BDDE-crosslinked PEI-impregnated sorbents exhibited the most stable long-term stability with the highest CO 2 adsorption capacity and the smallest weight gain after regeneration by simulated temperature swing adsorption (TSA) operations; the hydroxyl groups produced from BDDE-crosslinked PEI enhanced the CO 2 utilization by acting as proton acceptors. The effect of the BDDE content was investigated. The advanced physical stability was observed by an increase in the viscosity at high temperatures or gelation with increasing amounts of BDDE. The BDDE-crosslinked PEI-impregnated sorbents with the appropriate amount of BDDE showed an outstanding stability for the cyclic adsorption capacity (determined by simulated TSA operations) and resistance to urea formation (indicated by in situ infrared analysis).

Amine double-functionalized adsorbents were fabricated using silica gel as supports and their capabilities for CO2 capture were examined. Aminopropyltrimethoxysilane (1N-APS), and N1-(3-trimethoxysilylpropyl)diethylenetriamine (3N-APS) were used as grafted amine compounds, and tetraethylenepentamine and polyethyleneimine were used as impregnated species. The influence of double-functionalization method on the CO2 adsorption performance and textural properties of adsorbents was investigated. The adsorption capacity, the amine efficiency, and the thermal stability of double-functionalized sorbents depend strongly upon molecular variables associated with two different functional states (i.e., chemically grafted and physically impregnated amines). The temperature dependence of adsorption isotherms reveals that the CO2 adsorption behavior in the double-functionalized adsorbents follow the diffusion limitation model proposed by Xu et al. (Energy Fuels 16:1463–1469, 2002) where the CO2 adsorption is helped by the diffusion of impregnated amines. It is also found that the adsorption isotherm in the double-functionalized sorbent system with a proper choice for grafted and impregnated amines is nearly independent of temperature, which may offer a novel means to fabricate practically useful sorbents that can be used in a wide range of temperature without loss of CO2 adsorption capacity.

(3-Aminopropyl)trimethoxysilane (APS)-silica gels were prepared by a one-pot process using sodium silicate as a low-cost source of silica. XRD and SEM analyses revealed that the APS-silica gels were particles with diameters of around 100–200 nm. Furthermore, the introduction of amine groups was confirmed by FT-IR spectroscopy and CO2 uptake measurements. The adsorption properties of the gels were improved by addition of the surfactants hexadecyltrimethylammonium bromide (CTAB), Pluronic F127, and Pluronic P123, which acted as pore forming agents. Using Brunauer–Emmett–Teller (BET) analyses, we confirmed that both the surface area and pore volume were improved on addition of these surfactants. The larger surface area resulted in a greater number of amine groups being exposed on the outer surface of the APS-silica gels; therefore, CO2 uptake increased as the amount of surfactant used was increased. The APS-silica gels with F127 and P123 had pores from the porous particles with 5–11 nm diameters and gaps bet...

Purpose Natural orifice transluminal endoscopic surgery (NOTES) is a next generation surgical method with many promising benefits. Many snake-like NOTES platforms have been developed, but the lack of a proper control algorithm prevents those platforms from being used in practices. This study proposes an intuitive control algorithm for snake-like NOTES platforms, which is simple in structure and easily applicable to various NOTES systems.

Mitotic cell division increases tumour mutation burden and copy number load, predictive markers of the clinical benefit of immunotherapy. Cell division correlates also with genomic demethylation involving methylation loss in late-replicating partial methylation domains. Here we find that immunomodulatory pathway genes are concentrated in these domains and transcriptionally repressed in demethylated tumours with CpG island promoter hypermethylation. Global methylation loss correlated with immune evasion signatures independently of mutation burden and aneuploidy. Methylome data of our cohort (n = 60) and a published cohort (n = 81) in lung cancer and a melanoma cohort (n = 40) consistently demonstrated that genomic methylation alterations counteract the contribution of high mutation burden and increase immunotherapeutic resistance. Higher predictive power was observed for methylation loss than mutation burden. We also found that genomic hypomethylation correlates with the immune escape signatures of aneuploid tumours. Hence, DNA methylation alterations implicate epigenetic modulation in precision immunotherapy., Demethylation of the genome is found in cancer. Here, the authors show that genomic demethylation entails changes in promoter methylation and gene expression associated with immune escape and suggest that the epigenetic alterations may be an important determinant of responses to immunotherapy.

Recently, endovascular coil embolization has been introduced to treat intracranial aneurysms because it has lower morbidity and mortality than surgical clipping. The endovascular coils prevent the extravasation of blood by decreasing the permeability of an aneurysm flow governed by Darcy's law. Here, we developed and explored Pt-coated micro-ropes for potential use as endovascular coils. Electrospinning with subsequent electroplating were employed to fabricate Pt-coated nanofibers, which were tightly twisted to form micro-ropes. The compatibility of Pt micro-ropes with commercial delivery catheters was verified and their performance was experimentally explored in an in vitro experimental model. The developed Pt-coated micro-ropes demonstrated feasibility as efficient and low-cost endovascular coils. Statement of Significance The use of Platinum (Pt)-coated polymer nanofibers to prevent blood extravasation has been demonstrated. These Pt nanofibers were installed within a microfluidic channel, and the resulting reduced permeability was evaluated using a fluid similar to blood. Based on the obtained results, these newly developed nanofibers are expected to decrease the operation cost for aneurysmal subarachnoid hemorrhage (SAH), owing their reduced size and low material cost. Overall, the use of this new material should reduce the operational risk associated with the multiple steps required to place the Pt coils at the SAH site. The compatibility of Pt micro-ropes with commercial delivery catheters was verified and their performance was experimentally explored in an in vitro experimental model. The developed Pt-coated micro-ropes demonstrated feasibility as efficient and low-cost endovascular coils.

CO

Aberrant transcription of the pericentromeric human satellite II (HSATII) repeat is present in a wide variety of epithelial cancers. In deriving experimental systems to study its deregulation, we observed that HSATII expression is induced in colon cancer cells cultured as xenografts or under nonadherent conditions in vitro, but it is rapidly lost in standard 2D cultures. Unexpectedly, physiological induction of endogenous HSATII RNA, as well as introduction of synthetic HSATII transcripts, generated cDNA intermediates in the form of DNA/RNA hybrids. Single molecule sequencing of tumor xenografts showed that HSATII RNA-derived DNA (rdDNA) molecules are stably incorporated within pericentromeric loci. Suppression of RT activity using small molecule inhibitors reduced HSATII copy gain. Analysis of whole-genome sequencing data revealed that HSATII copy number gain is a common feature in primary human colon tumors and is associated with a lower overall survival. Together, our observations suggest that cancer-associated derepression of specific repetitive sequences can promote their RNA-driven genomic expansion, with potential implications on pericentromeric architecture.

A substantial fraction of disease-causing mutations are pathogenic through aberrant splicing. Although genome profiling studies have identified somatic single-nucleotide variants (SNVs) in cancer, the extent to which these variants trigger abnormal splicing has not been systematically examined. Here we analyzed RNA sequencing and exome data from 1,812 patients with cancer and identified ∼900 somatic exonic SNVs that disrupt splicing. At least 163 SNVs, including 31 synonymous ones, were shown to cause intron retention or exon skipping in an allele-specific manner, with ∼70% of the SNVs occurring on the last base of exons. Notably, SNVs causing intron retention were enriched in tumor suppressors, and 97% of these SNVs generated a premature termination codon, leading to loss of function through nonsense-mediated decay or truncated protein. We also characterized the genomic features predictive of such splicing defects. Overall, this work demonstrates that intron retention is a common mechanism of tumor-suppressor inactivation.

In this paper, an approach to extend the life of lead-acid batteries through the elimination of sulfation with “rest time” using the pulse current of a conventional DPV (Differential Pulse Voltammetry) method is discussed. A new rest time without “0” current in “saw-tooth” pattern pulses is proposed to overcome the “0” current (blackout period), which is a shortcoming of DPV. This will enable the proposed method to be used in the loaded state. In the proposed approach, ESSs (Energy Storage Systems) were discharged for 5 h twice per day for 6 months on weekdays. To observe the changes in the lifespan of the systems, for the same period, the changes in the impedances of lead-acid batteries which were being charged e without charging and discharging were measure and compared. This study is focused on determining the effectiveness of lead-acid batteries as ESSs.

Ethylenediamine was grafted onto a polystyrene surface to study the relationship between amine density and amine efficiency. Amine-tethered polystyrene was synthesized in two steps: (1) chloromethy...

【Poly(methyl methacrylate) (PMMA) supports and amine additives were investigated to adsorb $CO_2$ . PMMA supports were fabricated by using different ratio of pore forming agents (porogen) to control the BET specific surface area, pore volume and distribution. Toluene and xylene are used for porogens. Supported amine sorbents were prepared by wet impregnation of tetraethylenepentamine (TEPA) on PMMA supports. So we could identify the effect of the pore structure of supports and the quantity of impregnated TEPA on the adsorption capacity. The increased amount of toluene as pore foaming agent resulted in the decreased average pore diameter and the increased BET surface area. Polymer supports with huge different pore distribution could be fabricated by controlling the ratio of porogen. After impregnation, the support with micropore structure is supposed the pore blocking and filling effect so that it has low $CO_2$ capacity and kinetics due to the difficulty of diffusing. Macropore structure indicates fast adsorption capacity and low influence of amine loading. In case of support with mesopore, it has high performance of adsorption capacity and kinetics. So high surface area and meso-/macro- pore structure is suitable for $CO_2$ capture.】

Organic-inorganic composite membranes were prepared with sulfonated poly(ether ether ketone) (SPEEK) and different amounts of silica to improve chemical stability and vanadium hindrance for a vanadium redox flow battery. The durability of the prepared composite membrane was verified using a self-made dummy cell system and fully charged vanadium cathode half-cell electrolyte, which contained oxidative vanadium ions (VO2+). The prepared composite membranes, with covalent crosslinking between the organic polymer and inorganic particles, resulted in reduced vanadium permeability and enhanced chemical stability. Ion exchange capacity, water uptake, proton conductivity, and vanadium permeability decreased with increasing silica content. Selectivity was defined to consider both permeability and proton conductivity and resulted in a membrane that exhibited both high proton conductivity and low ion permeability simultaneously. The prepared 1 wt% silica composite membrane showed 133-fold higher selectivity compared with that of a Nafion112 membrane. After the stability test, the composite membrane showed little change compared to the membrane before the stability test, which confirmed the commercial prospect of SPEEK/SiO2 composite membrane for a vanadium redox flow battery.

The least-squares support vector machine (LSSVM) strategy has played a crucial role in the forecasting of building energy consumption owing to its remarkable nonlinear mapping capabilities in prediction. In order to build an effective LSSVM method, its two free parameters, the regularization parameter and the kernel parameter, must be selected carefully. However, LSSVM using a conventional real-coded genetic algorithm (RCGA) or differential evolution algorithm (DEA) for determining the aforementioned two parameters consumes excessive amounts of computation time. In this study, a novel LSSVM for effective prediction of daily building energy consumption is designed by utilizing a hybrid of the direct search optimization (DSO) algorithm and RCGA, called the DSORCGA. The proposed DSORCGA differs from the conventional RCGA in terms of the reproduction operator and the crossover operator, and is used to optimize free parameters of LSSVM for faster computation speed and higher predictive accuracy. Finally, in a MATLAB2010a environment, actual building energy consumption data are adopted to run the proposed DSORCGA-LSSVM and conventional RCGA-LSSVM and DEA-LSSVM. Further, the simulation results in the target period are compared with those of actual recorded energy consumption data, and improvement in computation time is revealed via numerical simulation.

The ZSM-5-type zeolites were prepared using three types of structure directing agent to investigate the effect of pore structure and PEI impregnation on the CO 2 adsorption capacity. The CO 2 capacity was primarily affected by the number of the adsorption site and the volume for trapping CO 2 . CO 2 was well adsorbed inside the micropore with stronger electric field. The CO 2 capacity increased with increasing amounts of impregnated PEI until PEI loading exceeded the total pore volume, because PEI predominantly occupied the pores of ZSM-5. The ZSM-5 with large surface area and total pore volume was the most favorable for amine-impregnated ZSM-5.

Background To reduce the radiation exposure of patients and physicians during needle-based procedures, robotic needle insertion systems have been widely developed. However, during robotic needle insertion, the respiratory motion of the patient can cause serious injury. Methods A vision-based variable impedance control algorithm was introduced to compensate for the respiratory motion. The algorithm controls the robot so that the applied forces and moments on the needle are zero. Also, an oscillation observer was introduced to ensure patient safety. A preliminary test was performed using a seven degrees of freedom (7-DOF) robot and a phantom. Result It was found that the proposed algorithm greatly decreases damage to the phantom due to respiratory motion. Also, the proposed oscillation observer was able to ensure robot stability. Conclusions The proposed control scheme allows the robot to compensate for the respiratory motion to ensure patient safety during a needle-based procedure. Copyright © 2015 John Wiley & Sons, Ltd.

Long interspersed nuclear element-1 (L1) retrotransposons are normally suppressed in somatic tissues mainly by DNA methylation and antiviral defense. However, L1s can be desuppressed in cancers to act as insertional mutagens and cause genomic instability by creating DNA double strand breaks and chromosomal rearrangements. Whereas the frequency of somatic L1 insertions varies greatly among individual tumors, much remains to be learned about underlying genetic, cellular, or environmental factors. Here, our pan-gastrointestinal cancer genome analyses for stomach, colorectal, and esophageal tumors identified multiple correlates of L1 activity. Clinical indicators of tumor progression, such as tumor grade and patient age, showed positive association. Potential L1 expression suppressors such as TP53 and DNMT1, a DNA methyltransferase, were inactivated in tumors with frequent L1 insertions. Importantly, tumors with high immune activity, for example, due to viral infection or high tumor-antigen load, tended to carry a low number of L1 insertions in their genomes with high expression levels of L1 suppressors such as APOBEC3s and SAMHD1. Our analysis of the transcriptional effects of intragenic retrotransposon insertions demonstrated an increased risk of gene disruption in retrotransposition-prone cancers. In particular, we found a splicing-disrupting L1 insertion in an exon of MOV10, a key L1 suppressor, which caused exon skipping with evidence of nonsense-mediated decay in a tumor with a high L1 insertion load. Our results indicate that cancer immunity may contribute to genome stability by suppressing L1 retrotransposition particularly in gastrointestinal cancers.

In this study, the Janus silica particles were prepared by grafting reaction based on the sol-gel method. Before the surface modification reaction, the silica particles were trapped in the PS layer and some fraction of their surface were only reacted with APTES. XPS analysis confirmed that the nitrogen compounds were introduced on the surface of the Janus particles, and the curve fitting of nitrogen confirmed that the compounds were the amine groups. From the result of SEM analysis, there were no differences in the size and the surface morphology and no formation of the APTES clusters. Based on these results, it was confirmed that the Janus silica particles were prepared using PS trapping layer.

Solid amine sorbents having adequate particle size with high CO2 adsorption capacity were successfully prepared using poly(ethylenimine) (PEI) as the amine and mesoporous poly(methyl methacrylate) (PMMA) beads as the support. The PEI-impregnated PMMA-supported sorbent exhibited CO2 adsorption capacity up to 4.26 mmol/g with PMMA-55 at 75 °C in pure CO2 gas flow. The effect of the temperature on the adsorption capacity of PMMA-55 was investigated, and the maximum adsorption capacity was obtained at 50 °C with a CO2 exposure time of 180 min, different from the tendency of most silica-supported sorbents. The effect of surfactant addition on the adsorption performance of PMMA-supported sorbents differed from those of silica-supported sorbents because of the different surface characteristics between PMMA and silica. Adsorption/desorption cycling was also performed to examine the suitability of the amine sorbent for potential application.

Tetraethylenepentamine (TEPA) was modified by Michael addition reactions to study the effect of primary, secondary, and tertiary amine structure on its ability to absorb or desorb carbon dioxide. TEPA and modified TEPA were impregnated in a poly(methyl methacrylate) support to obtain solid amines. The specific characteristics such as pH, viscosity, and thermal stability were measured to study the properties of liquid amine. Structural properties, adsorption capacity, rate of adsorption, desorption energy, and sorbent durability during CO 2 adsorption/desorption processes were measured to study the properties of solid amines. The pH of modified liquid TEPA (T1AN, T2AN, and T3AN) was slightly reduced; however, both viscosity and thermal stability were increased. The increased viscosity of the modified amines was indicative of an increase in attraction between the amine molecules; accordingly, amine leaching decreased noticeably and thermal stability of amines increased. Modified amine-impregnated sorbent (ST1AN and ST2AN) showed slight decrease in CO 2 adsorption capacity but noticeable increase in rates of adsorption, durability during cyclic tests, and desorption characteristics compared to TEPA-impregnated sorbent (STEPA).

In this study, highly luminescent carbon dots with diameters of 3–5 nm were synthesized via the carbonization of citric acid, and the effects of surface passivation and carbonization temperature on the optical properties were investigated. A red-shift in the emission wavelength was observed with increasing excitation wavelength, and oleylamine-capped carbon dots showed the highest quantum yield of approximately 43% when excited at 380 nm, whereas the reaction temperature had no influence on the emission wavelength and morphology of the dots. Additionally, I–III–VI AgInS2 nanocrystals (NCs) were prepared by thermal decomposition at a low temperature, and the emission wavelength was tuned by adjusting the growth temperature or introducing Zn ions, which enhanced the quantum yield up to 50%. For carbon dot application, a white LED was fabricated by combining a 380 nm UV LED with the carbon dots and Zn-doped AgInS2 NCs. White light from this LED exhibited an excellent color rendering index of greater than 95 with a warm color temperature, and demonstrated its potential for use in solid state lighting.

Yellow emitting Ca 2 BO 3 Cl:Eu 2+ phosphor was prepared by solid state reaction at 900 °C. The particle was monoclinic crystal structure, and showed broad band emission at around 540–590 nm due to the 5d–4f transition. Single Ca 2 BO 3 Cl:Eu 2+ phosphor converted white LED exhibited the CIE coordinates of (0.3441, 0.2675) with low CRI of 67.4. Hybridization of Ca 2 BO 3 Cl:Eu 2+ with 535 and 610 nm emitting CdSe/ZnS nanocrystals contributed to increasing white spectrum and generated the warm color temperature (4055 K) with high CRI (83.9) of white light. The acceptable color stability was also observed from (0.3687, 0.3051) at 20 mA to (0.3645, 0.3101) at 80 mA.

Purpose To assess the effects of probe load and speed on thyroid ultrasonography, an apparatus was designed to capture ultrasound images of a thyroid phantom under various ultrasound probe loads and speeds.

Purpose In this study, we measured the needle insertion force exerted on various breast tissues including those of a breast phantom, cattle tissue, and human tissue, according to needle insertion speed, and compared it using finite element analysis.

Long interspersed nuclear element-1 (L1) retrotransposons are normally suppressed in somatic tissues, mainly by DNA methylation and antiviral defense. However, L1s can be de-suppressed in cancers to act as insertional mutagens and cause genomic instability by creating DNA double-strand breaks and chromosomal rearrangements. Whereas the frequency of somatic L1 insertions varies greatly among individual tumors, much remains to be learned about underlying genetic, cellular, or environmental factors. Here, our pan-gastrointestinal cancer genome analyses for stomach, colorectal, and esophageal tumors identified multiple correlates of L1 activity. Clinical indicators of tumor progression, such as tumor grade and patient age, showed positive association. Potential L1 expression suppressors such as TP53 and DNMT1, a DNA methyltransferase, were inactivated in tumors with frequent L1 insertions. Importantly, tumors with high immune activity, for example, due to viral infection or high tumor-antigen load, tended to carry a low number of L1 insertions in their genomes with high expression levels of L1 suppressors such as APOBEC3s and SAMHD1. Our analysis of the transcriptional effects of intragenic retrotransposon insertions demonstrated an increased risk of gene disruption in retrotransposition-prone cancers. In particular, we found a splicing-disrupting L1 insertion in an exon of MOV10, a key L1 suppressor, which caused exon skipping with evidence of nonsense-mediated decay in a tumor with a high L1 insertion load. Our results indicate that cancer immunity may contribute to genome stability by suppressing L1 retrotransposition, particularly in gastrointestinal cancers. Citation Format: Hyunchul Jung, Jung Kyoon Choi, Eunjung Alice Lee. Cancer immunity contributes to genome stability by suppressing L1 retrotransposition in gastrointestinal cancers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5755.

The efficient electrochemical conversion of CO2 to fuels or stock chemicals with high-energy density would be a major step forward in the introduction of a carbon neutral energy cycle, as it would allow for the direct low-temperature conversion of (photo)-generated electrical current to stored chemical energy, in a manner very similar to the way nature stores solar energy. The high activity and selectivity towards electrocatalytic conversion of CO2 can be achieved with careful selection of catalyst and electrolyte. Major progress in electrochemical CO2 reduction has been limited to two-electron involved products such as CO and formate. It has been known that Cu is prone to produce hydrocarbons, mainly C1 product such as methane and the formation of multi-carbon products via C-C coupling remains as one of the biggest scientific challenges to be resolved. The product selectivity of such conversion can be affected by the electrolyte composition and catalyst structure. Anion such as halides in the electrolyte nanostructures copper surface via electrochemical cycling which allows for a suppression of methane and an enhancement of ethylene and ethanol formation. On the other hands, cations have direct influence on CO2RR in which increasing the size of mono-valent cations can increase the selectivity and activity to C-C coupled products by lowering the pK a of the hydrated cations at the cathode. In addition, a new principle of catalyst design which controls an atomic-level catalyst structure to accelerate electrocatalytic activity and selectivity toward the formation of C-C bonds will be discussed.

The reduction of optical losses in mono-crystalline silicon solar cell by surface texturing is a critical step to improve the overall cell efficiency. In this study, we have changed the sub-micrometer structure on the micrometer pyramidal structure by 2-step texturing. The Ag particles were coated on the micrometer pyramid surface in solution, and then the etching with hydrogen fluoride and hydrogen peroxide created even smaller nano-pyramids in these pyramids. As a result, we observed that the changes of size and thickness of nano structure on pyramidal surface were determined by concentration and etching time. Using 2-step texturing, the surface of wafers is etched to resemble the rough surface of a lotus leaf. Lotus surface can reduce average reflectance from 10% to below 3%. This reflectance is less than conventional textured wafer including anti-reflection coating.

The article examines admission policy issues related to curriculum development and implementation for the gifted education in science at special high schools in Korea. High school admission policies provided a means to identify and select a population of the scientifically gifted with certain characteristics and gave major directions for curriculum development while university admission policies had significant influences on curriculum implementation in special high schools. The admission policies for science high schools in Korea selected a homogeneous group of high achievers in all subject areas while special high schools for the gifted tended to select a heterogeneous group of the scientifically gifted in various areas of science including physics, chemistry, biology, earth science or information technology. University admission policies seemed to function as a parameter to achieve successful curriculum implementation.

Rheological properties of the polystyrene (PS) and poly(methyl methacrylate) (PMMA) blends were studied by Advanced Rheometric Expansion System (ARES). Storage modulus and loss modulus of the PS and PMMA blends were measured, and the interfacial tension of the PS and PMMA blends were obtained with various emulsion models by using the storage modulus and loss modulus of the blends. The value of interfacial tension estimated from the Palierne emulsion model was found to be 2.0 mN/m. Also, the interfacial tension between PS and PMMA was calculated by a theoretical model. The values of interfacial tension of the PS and PMMA blends obtained by the experiment and theoretical model were found to be in good agreement.

In this study, alkali earth thio-selenide phosphor, SrS x Se 1 − x :Eu 2+ , was prepared using the conventional solid state reaction method. The synthesized phosphor displayed a broad excitation band that was suitable for blue or near UV LED applications and emitted light at various wavelengths (563–605 nm) with different chemical compositions. Like the case of other alkali phosphors, Zn 2+ substitution for Sr 2+ greatly enhanced the emission of this thio-selenide phosphor. The LED fabricated with the synthesized phosphor produced white light using a blue LED with a CIE-1931 coordinate, T c and R a of (0.3199, 0.3107), 6577 K and 51.6, respectively.

To reduce the radiation exposure of patients and physicians during needle-based procedures, robotic needle insertion systems have been widely developed. However, during robotic needle insertion, the respiratory motion of the patient can cause serious injury.A vision-based variable impedance control algorithm was introduced to compensate for the respiratory motion. The algorithm controls the robot so that the applied forces and moments on the needle are zero. Also, an oscillation observer was introduced to ensure patient safety. A preliminary test was performed using a seven degrees of freedom (7-DOF) robot and a phantom.It was found that the proposed algorithm greatly decreases damage to the phantom due to respiratory motion. Also, the proposed oscillation observer was able to ensure robot stability.The proposed control scheme allows the robot to compensate for the respiratory motion to ensure patient safety during a needle-based procedure.

Natural orifice transluminal endoscopic surgery (NOTES) is an emerging surgical technique. We aimed to design, create, and evaluate a new semi-automatic snake robot for NOTES. The snake robot employs the characteristics of both a manual endoscope and a multi-segment snake robot. This robot is inserted and retracted manually, like a classical endoscope, while its shape is controlled using embedded robot technology. The feasibility of a prototype robot for NOTES was evaluated in animals and human cadavers. The transverse stiffness and maneuverability of the snake robot appeared satisfactory. It could be advanced through the anus as far as the peritoneal cavity without any injury to adjacent organs. Preclinical tests showed that the device could navigate the peritoneal cavity. The snake robot has advantages of high transverse force and intuitive control. This new robot may be clinically superior to conventional tools for transanal NOTES.

Crystallization behavior and rheological properties of blends of bisphenol-A polycarbonate (PC) and polypropylene (PP) prepared by screw extrusion have been investigated by differential scanning calorimetry (DSC), polarized-light microscopy, scanning electron microscopy, and a Rheometrics Mechanical Spectrometer. In the study of thermal analysis of PC-PP blends by DSC, double crystallization peaks were observed in the PC-rich compositions. In the study of spherulite of 7/3 PC-PP blend, large droplets (>25 μm) of PP were crystallized between 115°C and 105°C, and then small droplets (

The thermal properties of blends of poly(ether ether ketone) (PEEK) and poly(ether imide) (PEI) prepared by screw extrusion were investigated by differential scanning calorimetry. From the thermal analysis of amorphous PEEK–PEI blends which were obtained by quenching in liquid nitrogen, a single glass transition temperature (Tg) and negative excess heat capacities of mixing were observed with the blend composition. These results indicate that there is a favorable interaction between the PEEK and PEI in the blends and that there is miscibility between the two components. From the Lu and Weiss equation and a modified equation from this work, the polymer–polymer interaction parameter (χ12) of the amorphous PEEK–PEI blends was calculated and found to range from −0.058 to −0.196 for the extruded blends with the compositions. The χ12 values calculated from this work appear to be lower than the χ12 values calculated from the Lu and Weiss equation. The χ12 values calculated from the Tg method both ways decreased with increase of the PEI weight fraction. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 72: 733–739, 1999

Blends of a thermotropic liquid crystalline polymer (LCP) with poly(ether imide) (PEI), poly(ether ether ketone) (PEEK), polysulfone (PSF) and polyarylsulfone (PAS) prepared by screw extrusion have been investigated by differential scanning calorimeter and dynamic mechanical thermal analysis. From the measured glass transition temperature (Tg) and specific heat increment (ΔCp) at the Tg, it appears that the LCP dissolves more in the PEI- and PEEK-rich phases than does the PEI and PEEK in the LCP-rich phase. From the DSC study of PSF-LCP and PAS-LCP blends, the Tg(PSF) and Tg(PAS) of each blends are almost constant with blend composition. Therefore, it is concluded that PSF and PAS are immiscible with LCP. The polymer-polymer interaction parameter (χ12) and the degree of disorder (y/x1) of LCP have been investigated using the Flory lattice theory in which the anisotropy of LCP is considered. The χ12 values have been calculated from the Tg data and found to be 0.181 ± 0.004 at 593 K for the PEI-LCP blends and 0.069 ± 0.006 at 623 K for the PEEK-LCP blends. Using the previously presented method, the χ12 and y/x1 in partially miscible systems have been determined.

Limiting oxygen index (LOI) value, glass transition temperature (Tg), thermal degradation profile, morphology, and tensile strength and elongation at break of the flame-retarding polycarbonate (PC)-poly(acrylonitrile- butadiene-styrene) (ABS) (7/3) blends were studied. The flame retardants used were huntite-hydromagnetite compounds (HHM), triphenyl phosphate (TPP), zinc stannate, and antimony trioxide. The LOI values were increased with the increase of TPP content, but they did not change significantly when the HHM was used as a flame retardant Glass transition temperatures of the flame-retarding PC-ABS (7/3) blends were decreased significantly when TPP was added to the blends. This is mainly due to the plasticizing effect of the TPP on the PC-ABS (7/3) blends. In the flame-retarding PC-ABS (7/3) blends, the LOI value, tensile strength, and elongation at break were measured and found to be 24.6 - 31.6%, 41.4 - 50.3 MPa, and 2.16 - 33.7%, respectively. These LOI values and mechanical properties were achieved when the TPP, zinc stannate, and antimony trioxide were used as flame retardants, and when dodecylbenzenesulfonic acid sodium salt and dimethylsulfone were used as additives into the PC-ABS (7/3) blends.