bluuebunny/crossref_metadata_2025 huggingface dataset:
Extracellular Vesicles from Cancer-Associated Fibroblasts Containing Annexin A6 Induces FAK-YAP Activation by Stabilizing β1 Integrin, Enhancing Drug Resistance
Authors: Uchihara Tomoyuki , Miyake Keisuke , Yonemura Atsuko , Komohara Yoshihiro , Itoyama Rumi , Koiwa Mayu , Yasuda Tadahito , Arima Kota , Harada Kazuto , Eto Kojiro , Hayashi Hiromitsu , Iwatsuki Masaaki , Iwagami Shiro , Baba Yoshifumi , Yoshida Naoya , Yashiro Masakazu , Masuda Mari , Ajani Jaffer A. , Tan Patrick , Baba Hideo , Ishimoto Takatsugu
Published: June 2020

Extracellular vesicles (EV) from cancer-associated fibroblasts (CAF) are composed of diverse payloads. Although CAFs impact the aggressive characteristics of gastric cancer cells, the contribution of CAF-EV to gastric cancer progression has not been elucidated. Here, we investigated the molecular mechanism of the changes in gastric cancer characteristics induced by CAF-EV. CAF abundance in gastric cancer tissues was associated with poor prognosis of patients with gastric cancer receiving chemotherapy. Moreover, CAF-EV induced tubular network formation and drug resistance of gastric cancer cells in the extracellular matrix (ECM). Comprehensive proteomic analysis of CAF-EV identified that Annexin A6 plays a pivotal role in network formation and drug resistance of gastric cancer cells in the ECM via activation of β1 integrin-focal adhesion kinase (FAK)-YAP. A peritoneal metastasis mouse model revealed that CAF-EV induced drug resistance in peritoneal tumors, and inhibition of FAK or YAP efficiently attenuated gastric cancer drug resistance in vitro and in vivo. These findings demonstrate that drug resistance is conferred by Annexin A6 in CAF-EV and provide a potential avenue for overcoming gastric cancer drug resistance through the inhibition of FAK-YAP signaling in combination with conventional chemotherapeutics.

Significance:

This study elucidates a novel molecular mechanism through which Annexin A6 in CAF-EV activates FAK-YAP by stabilizing β1 integrin at the cell surface of gastric cancer cells and subsequently induces drug resistance.
Traditional Diagnostics versus Disruptive Technology: The Role of the Pathologist in the Era of Liquid Biopsy
Authors: Sholl Lynette M. , Oxnard Geoffrey R. , Paweletz Cloud P.
Published: June 2020

Precision medicine in cancer care is predicated on access to several fundamental pieces of data: (i) a precise tumor diagnosis, (ii) accurate stage classification, and (iii) protein or molecular biomarkers that predict efficacy of targeted therapies. For all patients with cancer, these data points are generated by obtaining a tumor sample and subjecting it to analysis by a pathologist and, when appropriate, a molecular pathologist. While tumor diagnosis and pathologic staging (gross and microscopic examination of the primary tumor and draining lymph nodes) require the infrastructure and expertise of an anatomic pathology program, the advent of “liquid biopsy” has driven a shift in molecular biomarker testing away from local pathology laboratories and into high-throughput, centralized (and often for-profit) laboratories. What does this mean for patient care? How is the role of the pathologist affected? What are the implications for integration of diagnostic information and ultimately for appropriate therapy selection? This article will consider the current testing landscape, address current challenges in the use of liquid biopsy in clinical practice, and consider ways the pathologist should be involved in interpreting liquid biopsy data in the context of the patient's cancer diagnosis and stage.
Lymphatic Vessels in Tumor Dissemination versus Immunotherapy
Authors: Vaahtomeri Kari , Alitalo Kari
Published: June 2020

During the growth of various cancers, primary tumors can escape antitumor immune responses of their host and eventually disseminate into distant organs. Peritumoral lymphatic vessels connect the primary tumor to lymph nodes, facilitating tumor entry into lymph nodes, systemic circulation, and metastasis. Lymph node metastases that occur frequently provide sites of tumor cell spread, whereas tumor antigen transfer into and presentation in tumor-draining lymph nodes induce activation of tumor-specific T-lymphocyte responses that can result in cytolytic targeting of the tumor. Here, we discuss the recently emerged controversial role of the lymphatic vessels in tumor dissemination and cancer immunotherapy.
KRASQ61H Preferentially Signals through MAPK in a RAF Dimer-Dependent Manner in Non–Small Cell Lung Cancer
Authors: Zhou Zhi-Wei , Ambrogio Chiara , Bera Asim K. , Li Qing , Li Xing-Xiao , Li Lianbo , Son Jieun , Gondi Sudershan , Li Jiaqi , Campbell Emily , Jin Hua , Okoro Jeffrey J. , Xu Cheng-Xiong , Janne Pasi A. , Westover Kenneth D.
Published: June 2020

Assembly of RAS molecules into complexes at the cell membrane is critical for RAS signaling. We previously showed that oncogenic KRAS codon 61 mutations increase its affinity for RAF, raising the possibility that KRASQ61H, the most common KRAS mutation at codon 61, upregulates RAS signaling through mechanisms at the level of RAS assemblies. We show here that KRASQ61H exhibits preferential binding to RAF relative to PI3K in cells, leading to enhanced MAPK signaling in in vitro models and human NSCLC tumors. X-ray crystallography of KRASQ61H:GTP revealed that a hyperdynamic switch 2 allows for a more stable interaction with switch 1, suggesting that enhanced RAF activity arises from a combination of absent intrinsic GTP hydrolysis activity and increased affinity for RAF. Disruption of KRASQ61H assemblies by the RAS oligomer–disrupting D154Q mutation impaired RAF dimerization and altered MAPK signaling but had little effect on PI3K signaling. However, KRASQ61H oligomers but not KRASG12D oligomers were disrupted by RAF mutations that disrupt RAF–RAF interactions. KRASQ61H cells show enhanced sensitivity to RAF and MEK inhibitors individually, whereas combined treatment elicited synergistic growth inhibition. Furthermore, KRASQ61H tumors in mice exhibited high vulnerability to MEK inhibitor, consistent with cooperativity between KRASQ61H and RAF oligomerization and dependence on MAPK signaling. These findings support the notion that KRASQ61H and functionally similar mutations may serve as predictive biomarkers for targeted therapies against the MAPK pathway.

Significance:

These findings show that oncogenic KRASQ61H forms a cooperative RAS–RAF ternary complex, which renders RAS-driven tumors vulnerable to MEKi and RAFi, thus establishing a framework for evaluating RAS biomarker-driven targeted therapies.
MRI Distinguishes Tumor Hypoxia Levels of Different Prognostic and Biological Significance in Cervical Cancer
Authors: Hillestad Tiril , Hompland Tord , Fjeldbo Christina S. , Skingen Vilde E. , Salberg Unn Beate , Aarnes Eva-Katrine , Nilsen Anja , Lund Kjersti V. , Evensen Tina S. , Kristensen Gunnar B. , Stokke Trond , Lyng Heidi
Published: June 2020

Tumor hypoxia levels range from mild to severe and have different biological and therapeutical consequences but are not easily assessable in patients. Here we present a method based on diagnostic dynamic contrast enhanced (DCE) MRI that reflects a continuous range of hypoxia levels in patients with tumors of cervical cancer. Hypoxia images were generated using an established approach based on pixel-wise combination of DCE-MRI parameters νe and Ktrans, representing oxygen consumption and supply, respectively. Using two tumor models, an algorithm to retrieve surrogate measures of hypoxia levels from the images was developed and validated by comparing the MRI-defined levels with hypoxia levels reflected in pimonidazole-stained histologic sections. An additional indicator of hypoxia levels in patient tumors was established on the basis of expression of nine hypoxia-responsive genes; a strong correlation was found between these indicator values and MRI-defined hypoxia levels in 63 patients. Chemoradiotherapy outcome of 74 patients was most strongly predicted by moderate hypoxia levels, whereas more severe or milder levels were less predictive. By combining gene expression profiles and MRI-defined hypoxia levels in cancer hallmark analysis, we identified a distribution of levels associated with each hallmark; oxidative phosphorylation and G2–M checkpoint were associated with moderate hypoxia, epithelial-to-mesenchymal transition, and inflammatory responses with significantly more severe levels. At the mildest levels, IFN response hallmarks together with HIF1A protein expression by IHC appeared significant. Thus, our method visualizes the distribution of hypoxia levels within patient tumors and has potential to distinguish levels of different prognostic and biological significance.

Significance:

These findings present an approach to image a continuous range of hypoxia levels in tumors and demonstrate the combination of imaging with molecular data to better understand the biology behind these different levels.
Radiation with STAT3 Blockade Triggers Dendritic Cell–T cell Interactions in the Glioma Microenvironment and Therapeutic Efficacy
Authors: Ott Martina , Kassab Cynthia , Marisetty Anantha , Hashimoto Yuuri , Wei Jun , Zamler Daniel , Leu Jia-Shiun , Tomaszowski Karl-Heinz , Sabbagh Aria , Fang Dexing , Gupta Pravesh , Priebe Waldemar , Zielinski Rafal J. , Burks Jared K. , Long James P. , Kong Ling-Yuan , Fuller Gregory N. , DeGroot John , Sulman Erik P. , Heimberger Amy B.
Published: June 2020

Purpose:

Patients with central nervous system (CNS) tumors are typically treated with radiotherapy, but this is not curative and results in the upregulation of phosphorylated STAT3 (p-STAT3), which drives invasion, angiogenesis, and immune suppression. Therefore, we investigated the combined effect of an inhibitor of STAT3 and whole-brain radiotherapy (WBRT) in a murine model of glioma.

Experimental Design:

C57BL/6 mice underwent intracerebral implantation of GL261 glioma cells, WBRT, and treatment with WP1066, a blood–brain barrier–penetrant inhibitor of the STAT3 pathway, or the two in combination. The role of the immune system was evaluated using tumor rechallenge strategies, immune-incompetent backgrounds, immunofluorescence, immune phenotyping of tumor-infiltrating immune cells (via flow cytometry), and NanoString gene expression analysis of 770 immune-related genes from immune cells, including those directly isolated from the tumor microenvironment.

Results:

The combination of WP1066 and WBRT resulted in long-term survivors and enhanced median survival time relative to monotherapy in the GL261 glioma model (combination vs. control P < 0.0001). Immunologic memory appeared to be induced, because mice were protected during subsequent tumor rechallenge. The therapeutic effect of the combination was completely lost in immune-incompetent animals. NanoString analysis and immunofluorescence revealed immunologic reprograming in the CNS tumor microenvironment specifically affecting dendritic cell antigen presentation and T-cell effector functions.

Conclusions:

This study indicates that the combination of STAT3 inhibition and WBRT enhances the therapeutic effect against gliomas in the CNS by inducing dendritic cell and T-cell interactions in the CNS tumor.
Addition of Antiestrogen Treatment in Patients with Malignant PEComa Progressing to mTOR Inhibitors
Authors: Sanfilippo Roberta , Fabbroni Chiara , Fucà Giovanni , Fumagalli Elena , Morosi Carlo , Sbaraglia Marta , Gronchi Alessandro , Collini Paola , Dei Tos Angelo P. , Casali Paolo G.
Published: June 2020

Purpose:

Perivascular epithelioid cell tumors (PEComa) are rare mesenchymal neoplasms. mTOR inhibitors are the most active agents in PEComa and in patients progressing to mTOR inhibitors, other available therapies have limited benefit. Preclinical evidences showed a cross-talk between the mTOR pathway and estrogen receptor signaling. This provided a rationale for adding an antiestrogen treatment in female patients becoming resistant to mTOR inhibitors.

Experimental Design:

Since April 2018, female patients with advanced/metastatic PEComa progressing to mTOR inhibitors were treated with a combination of sirolimus and exemestane with or without LHRH analogue (based on menopausal status). This case series was retrospectively reviewed. Survival analyses were performed using the Kaplan–Meier method.

Results:

A total of seven consecutive patients treated with the combination of sirolimus and antiestrogen treatment were retrospectively reviewed. Six (86%) received a combination of sirolimus and exemestane, whereas one patient (14%) received a combination of sirolimus, exemestane, and triptorelin since in premenopausal status. After a median follow-up of 13.1 months, three patients (43%) experienced a partial response, three patients (43%) experienced a stabilization of disease, and one patient (14%) had disease progression with an overall response rate of 43% and a disease control rate of 86%.

Conclusions:

In this small retrospective case series, the addition of antiestrogen treatment in female patients with advanced PEComa progressing to mTOR inhibitors resulted in a remarkable clinical benefit in a setting where no other options are available.
Repurposing the FDA-Approved Antiviral Drug Ribavirin as Targeted Therapy for Nasopharyngeal Carcinoma
Authors: Huq Sakibul , Casaos Joshua , Serra Riccardo , Peters Michael , Xia Yuanxuan , Ding Andy S. , Ehresman Jeff , Kedda Jayanidhi N. , Morales Manuel , Gorelick Noah L. , Zhao Tianna , Ishida Wataru , Perdomo-Pantoja Alexander , Cecia Arba , Ji Chenchen , Suk Ian , Sidransky David , Brait Mariana , Brem Henry , Skuli Nicolas , Tyler Betty
Published: June 2020

Nasopharyngeal carcinoma (NPC) is a squamous cell carcinoma with a proclivity for systemic dissemination, leading many patients to present with advanced stage disease and fail available treatments. There is a notable lack of targeted therapies for NPC, despite working knowledge of multiple proteins with integral roles in NPC cancer biology. These proteins include EZH2, Snail, eIF4E, and IMPDH, which are all overexpressed in NPC and correlated with poor prognosis. These proteins are known to be modulated by ribavirin, an FDA-approved hepatitis C antiviral that has recently been repurposed as a promising therapeutic in several solid and hematologic malignancies. Here, we investigated the potential of ribavirin as a targeted anticancer agent in five human NPC cell lines. Using cellular growth assays, flow cytometry, BrdU cell proliferation assays, scratch wound assays, and invasion assays, we show in vitro that ribavirin decreases NPC cellular proliferation, migration, and invasion and promotes cell-cycle arrest and cell death. Modulation of EZH2, Snail, eIF4E, IMPDH, mTOR, and cyclin D1 were observed in Western blots and enzymatic activity assays in response to ribavirin treatment. As monotherapy, ribavirin reduced flank tumor growth in multiple NPC xenograft models in vivo. Most importantly, we demonstrate that ribavirin enhanced the effects of radiotherapy, a central component of NPC treatment, both in vitro and in vivo. Our work suggests that NPC responds to ribavirin-mediated EZH2, Snail, eIF4E, IMPDH, and mTOR changes and positions ribavirin for clinical evaluation as a potential addition to our NPC treatment armamentarium.
Atypically High Reproductive Skew in a Small Wild Chimpanzee Community in a Human-Dominated Landscape
Authors: McCarthy Maureen S. , Lester Jack D. , Cibot Marie , Vigilant Linda , McLennan Matthew R.
Published: June 2020

Social rank is positively correlated with reproductive success in numerous species, albeit demographic factors often influence those patterns. In multimale primate species, reproductive skew tends to decrease with increasing numbers of males and sexually receptive females. Alpha male chimpanzees (Pan troglodytes) often sire a disproportionate, though somewhat variable, percentage of offspring compared to other males. In a small community of eastern chimpanzees inhabiting a human-dominated landscape in Bulindi, Uganda, we found extraordinarily high levels of alpha male reproductive success over a 5-year period (7/8 offspring = 88%), despite the presence of multiple subordinate males. The skew exceeds that reported in other studies of chimpanzees as well as closely related bonobos (Pan paniscus). Our findings underscore the role of demographic and social factors in male reproductive success and also suggest that conclusions about species differences may be premature. The interaction of small community size, dispersal limitations, and male reproductive strategies like those found here may decrease genetic diversity and increase the risk of concomitant inbreeding in chimpanzee communities under strong anthropogenic pressure.
Munich Comparative Study
Authors: Georgiev Stanimir , Ewert Peter , Eicken Andreas , Hager Alfred , Hörer Jürgen , Cleuziou Julie , Meierhofer Christian , Tanase Daniel
Published: June 2020

Background:

Percutaneous pulmonary valve implantation (PPVI) has become an important treatment of right ventricular outflow tract dysfunction. Studies directly comparing the long-term outcome of PPVI with the Melody valve to surgical pulmonary valve replacement (SPVR) are lacking.

Methods:

All patients treated with PPVI with the Melody valve and SPVR between January 2006 and December 2018 in our center were enrolled into a database and investigated with a standard follow-up protocol. The current study compares the outcomes in means of survival, reinterventions, infectious endocarditis, and performance of the valves.

Results:

The study included 452 patients, of whom 241 were treated with PPVI with the Melody valve and 211 patients with SPVR with different types of valves. Median follow-up time was 5.4 years (3 months to 12.5 years), and the total observation was 2449 patient-years. Estimated survival after 10 years was 94% in the Melody group and 92% in the SPVR group (
P
=0.47). There was no difference in the estimated survival free of surgery on the implanted valve at 10 years (Melody, 87%, versus SPVR, 87%;
P
=0.54) or in the survival with the originally implanted pulmonary valve (Melody group, 80%; SPVR group, 73%;
P
=0.46) between both groups. The annualized incidence of infective endocarditis was 1.6% in the Melody group and 0.5% in the SPVR group, and the estimated survival free of endocarditis did not differ significantly between groups (Melody group, 82%; SPVR group, 86%;
P
=0.082). Survival free of valve replacement because of infective endocarditis was comparable between both groups (Melody, 88%; SPVR, 88%;
P
=0.35).

Conclusions:

PPVI with the Melody valve and SPVR provides similar survival, freedom of reinterventions, and infective endocarditis with or without the need of replacement of the pulmonary valve. Being less invasive, PPVI should be considered a method for treatment for patients with dysfunctional right ventricular outflow tracts.
Cardiovascular Health Score and Lifetime Risk of Cardiovascular Disease
Authors: Bundy Joshua D. , Ning Hongyan , Zhong Victor W. , Paluch Amanda E. , Lloyd-Jones Donald M. , Wilkins John T. , Allen Norrina B.
Published: June 2020

Background:

Long-term risks of cardiovascular disease (CVD) according to levels of cardiovascular health (CVH) have not been characterized in a diverse, representative population.

Methods and Results:

We pooled individual-level data from 30 447 participants (mean [SD] age, 55.0 [13.9] years; 60.6% women; 31.8% black) from 7 US cohort studies. We defined CVH based on levels of 7 American Heart Association health metrics, scored as ideal (2 points), intermediate (1 point), or poor (0 points). The total CVH score was used to quantify overall CVH as high (12–14 points), moderate (9–11 points), or low (0–8 points). We used a modified Kaplan-Meier analysis, accounting for the competing risk of death, to estimate the lifetime risk of CVD (composite of incident myocardial infarction, stroke, heart failure, or CVD death) separately in white and black men and women free of CVD at index ages of <40, 40 to 59, and ≥60 years. High CVH was more prevalent among women compared with men, white compared with black participants, and in younger compared with older participants. During 538 477 person-years of follow-up, we observed 6546 CVD events. In women aged 40 to 59 years, those with high CVH had lower lifetime risk (95% CI) of CVD (white women, 12.6% [2.6%–22.6%]; black women, 0.0%) compared with moderate (white women, 16.6% [13.0%–20.2%]; black women, 12.7% [6.8%–18.5%]) and low (white women, 33.8% [30.6%–37.1%]; black women, 34.7% [30.4%–39.0%]) CVH strata. Patterns were similar for men and individuals <40 and ≥60 years of age.

Conclusions:

Higher baseline CVH at all ages in adulthood is associated with substantially lower lifetime risk for CVD compared with moderate and low CVH, in white and black men and women in the United States. Public health and healthcare efforts aimed at maintaining and restoring higher CVH throughout the life course could provide substantial benefits for the population burden of CVD.
gp130 Controls Cardiomyocyte Proliferation and Heart Regeneration
Authors: Li Yandong , Feng Jie , Song Shen , Li Haotong , Yang Huijun , Zhou Bin , Li Yan , Yue Zhang , Lian Hong , Liu Lihui , Hu Shengshou , Nie Yu
Published: June 2020

Background:

A key cause of the high mortality of cardiovascular diseases is the cardiomyocyte inability to renew after cardiac injury. As a promising strategy to supplement functional myocytes for cardiac repair, there is a pressing need to understand the cellular and molecular mechanisms of heart regeneration.

Methods:

Seven genetic mouse lines were used: global OSM (oncostatin M) knockout, monocyte-/macrophage-specific OSM deletion, cardiomyocyte-specific lines, including OSM receptor deletion, gp130 (glycoprotein 130) deletion, gp130 activation, and Yap (yes-associated protein) ablation with gp130 activation mice. A series of molecular signaling experiments, including RNA sequencing, immunostaining, coimmunoprecipitation, and imaging flow cytometry, were conducted. Two models of cardiac injury, apical resection and myocardial infarction operation, were performed in neonatal, juvenile, and adult mice. Heart regeneration and cardiac function were evaluated by Masson staining and echocardiography, respectively. Gene recombinant adenovirus-associated virus was constructed and infected myocardial-infarcted mice as a gene therapy.

Results:

OSM was identified by RNA sequencing as a key upstream regulator of cardiomyocyte proliferation during neonatal heart regeneration in mice. Cardiomyocyte proliferation and heart regeneration were suspended in neonatal mice after cardiac injury when OSM was conditionally knockout in macrophages. The cardiomyocyte-specific deficiency of the OSM receptor heterodimers, OSM receptor and gp130, individually in cardiomyocytes reduced myocyte proliferation and neonatal heart regeneration. Conditional activation of gp130 in cardiomyocytes promoted cardiomyocyte proliferation and heart regeneration in juvenile and adult mice. Using RNA sequencing and functional screening, we found that Src mediated gp130-triggered cardiomyocyte proliferation by activating Yap (yes-associated protein) with Y357 phosphorylation independently of the Hippo pathway. Cardiomyocyte-specific deletion of Yap in
Myh6-gp130

ACT

mice blocked the effect of gp130 activation–induced heart regeneration in juvenile mice. Gene therapy with adenovirus-associated virus encoding constitutively activated gp130 promoted cardiomyocyte proliferation and heart regeneration in adult mice after myocardial infarction.

Conclusions:

Macrophage recruitment is essential for heart regeneration through the secretion of OSM, which promotes cardiomyocyte proliferation. As the coreceptor of OSM, gp130 activation is sufficient to promote cardiomyocyte proliferation by activating Yap through Src during heart regeneration. gp130 is a potential therapeutic target to improve heart regeneration after cardiac injury.
Exposure to Air Pollution and Particle Radioactivity With the Risk of Ventricular Arrhythmias
Authors: Peralta Adjani A. , Link Mark S. , Schwartz Joel , Luttmann-Gibson Heike , Dockery Douglas W. , Blomberg Annelise , Wei Yaguang , Mittleman Murray A. , Gold Diane R. , Laden Francine , Coull Brent A. , Koutrakis Petros
Published: June 2020

Background:

Individuals are exposed to air pollution and ionizing radiation from natural sources through inhalation of particles. This study investigates the association between cardiac arrhythmias and short-term exposures to fine particulate matter (particulate matter ≤2.5 µm aerodynamic diameter; PM
2.5
) and particle radioactivity.

Methods:

Ventricular arrhythmic events were identified among 176 patients with dual-chamber implanted cardioverter-defibrillators in Boston, Massachusetts between September 2006 and June 2010. Patients were assigned exposures based on residential addresses. Daily PM
2.5
levels were estimated at 1-km×1-km grid cells from a previously validated prediction model. Particle gross β activity was used as a surrogate for particle radioactivity and was measured from several monitoring sites by the US Environmental Protection Agency’s monitoring network. The association of the onset of ventricular arrhythmias (VA) with 0- to 21-day moving averages of PM
2.5
and particle radioactivity (2 single-pollutant models and a 2-pollutant model) before the event was examined using time-stratified case-crossover analyses, adjusted for dew point and air temperatures.

Results:

A total of 1,050 VA were recorded among 91 patients, including 123 sustained VA among 25 of these patients. In the single-pollutant model of PM
2.5
, each interquartile range increase in daily PM
2.5
levels for a 21-day moving average was associated with 39% higher odds of a VA event (95% CI, 12%–72%). In the single-pollutant model of particle radioactivity, each interquartile range increase in particle radioactivity for a 2-day moving average was associated with 13% higher odds of a VA event (95% CI, 1%–26%). In the 2-pollutant model, for the same averaging window of 21 days, each interquartile range increase in daily PM
2.5
was associated with an 48% higher odds of a VA event (95% CI, 15%–90%), and each interquartile range increase of particle radioactivity with a 10% lower odds of a VA event (95% CI, –29% to 14%). We found that with higher levels of particle radioactivity, the effect of PM
2.5
on VAs is reduced.

Conclusions:

In this high-risk population, intermediate (21-day) PM
2.5
exposure was associated with higher odds of a VA event onset among patients with known cardiac disease and indication for implanted cardioverter-defibrillator implantation independently of particle radioactivity.
The New Critical Edition of the Martyrdom of the Fifteen Martyrs of Tiberioupolis (BHG 1199) by Irini-Sophia Kiapidou and Several Problems of the Text
Authors: Lourié Basil
Published: June 2020

The review-article discusses the new critical edition of BHG 1199 and its traditional attribution to Theophylact of Ohrid (which is rejected). The legend representing the conversion of Bulgaria with no participation of Cyril and Methodius or their disciples must go back to the tenth century First Bulgarian kingdom.
Fusarium xiangyunensis (Nectriaceae), a remarkable new species of nematophagous fungi from Yunnan, China

Authors: ZHANG FA , LIU SHUO-RAN , ZHOU XIN-JUAN , MONKAI JUTAMART , HONGSANAN SINANG , SHANG QIU-JU , HYDE KEVIN D. , YANG XIAO-YAN
Published: June 2020

Fusarium xiangyunensis sp. nov., isolated from hot-spring waterlogged soil in China, which is an endoparasitic fungus of nematodes, is described and illustrated. Evidence for the new species is provided by morphology and phylogenetic analyses of combined ITS, EF-1α and RPB1 sequence data. Phylogenetic analyses showed that F. xiangyunensis clustered with those species belonging to the F. solani species complex and grouped together with F. witzenhausenense. This species differs from F. witzenhausenense in habitat (parasitic on Hibiscus sp.), conidia and chlamydospores. Furthermore, the nematicidal activity of its microconidia was determined and causes infection and death of nematodes in both sterile water and solid medium.
Revision of the genus Corythalia C.L. Koch, 1850, part 1: Diagnosis and new species from South America (Araneae: Salticidae: Salticinae: Euophryini)
Authors: BAYER STEFFEN , HÖFER HUBERT , METZNER HEIKO
Published: June 2020

We propose a revision of the spider genus Corythalia C.L. Koch, 1850 (Salticidae: Euophryini) with a revised genus diagnosis based on examination of all species available to us. In this paper we redescribe all previously described species from South America with revised species diagnoses and describe 20 new species from South America (and the nearby islands). For C. latipes, the type species of the genus Corythalia, a neotype is designated. In total, 52 nominal species of the genus are herein treated, 46 species are recognized as valid. The females of C. waleckii Taczanowski, 1871, C. luctuosa Caporiacco, 1954 and C. latipes (C.L. Koch, 1846) are described for the first time. Corythalia sellata Simon, 1901, erroneously considered as nomen nudum in the present version of the World Spider Catalog, is here recognised as a valid species. Corythalia fulgipedia Crane, 1948 is also considered a valid species and is removed from the synonymy of C. tropica (Mello-Leitão, 1939). One name is considered a nomen dubium (Corythalia variegata Caporiacco, 1954), two are nomina nuda (C. major Simon, 1901; C. dimidiata Simon, 1901). Two species are transferred to other genera: C. argyrochrysos (Mello-Leitão, 1946) to Pachomius Peckham & Peckham, 1896 as Pachomius argyrochrysos (Mello-Leitão, 1946), comb. nov. and C. heliophanina (Taczanowski, 1871) to Neonella Gertsch, 1936, as Neonella heliophanina (Taczanowski, 1871), comb. nov. under incertae sedis. One species is synonymised: C. barbipes (Mello-Leitão, 1939) is a junior synonym of C. cincta (Badcock, 1932), syn. nov. The new Corythalia species are: C. conferta sp. nov. (♂♀, Brazil), C. concinna sp. nov. (♀, Brazil), C. drepane sp. nov. (♂♀, Brazil), C. drepanopsis sp. nov. (♀, Brazil), C. antepagmenti sp. nov. (♂♀, Brazil), C. ricti Bayer, sp. nov. (♂, Guyana), C. protensa sp. nov. (♂, Brazil), C. gasnieri sp. nov. (♂, Brazil), C. verhaaghi sp. nov. (♀, Brazil), C. scutellaris Bayer, sp. nov. (♂♀, Ecuador), C. dakryodes Bayer, sp. nov. (♀, Colombia), C. foelixi Bayer, sp. nov. (♂♀, French Guiana), C. longiducta sp. nov. (♀, Brazil), C. latior sp. nov. (♂, Bolivia), C. trochophora Bayer, sp. nov. (♂, Ecuador), C. lineata Bayer, sp. nov. (♂, Guyana), C. hamulifera Bayer, sp. nov. (♂, Ecuador), C. tribulosa sp. nov. (♂, Colombia), C. flagrans sp. nov. (♂, Brazil) and C. fragilis sp. nov. (♂♀, Brazil). Illustrations are provided for all of the new species and for all (primary) type specimens of the species re-described. Hypotheses of possible relationships among the different species of Corythalia are discussed.
Hydrogen Permeation and Its Impacts on the Electrical Performance of Stacked ZrO2/Al2O3/ZrO2 Films
Authors: Choi Pyungho , Cho Youngseung , Choi Byoungdeog
Published: June 2020

In this study, the effects of hydrogenation on the dielectric capacitance and leakage current of ZrO2/Al2O3/ZrO2 (ZAZ) films for dynamic-random-access memory (DRAM) capacitors were examined. Hydrogen permeation into ZAZ films reduced the dielectric
capacitance and increased the leakage current with continued exposure to hydrogen during the forming gas annealing process. More specifically, the hydrogen ions distributed in the grain boundaries and at the Z/A interfaces appeared to disrupt the dipole motion and diminish the dielectric constant
of the film, resulting in a decreased dielectric capacitance. Furthermore, the reaction of hydrogen atoms with the pre-existing oxygen of the ZrO2 films resulted in an oxygen vacancy with two captured electrons. Conduction electrons freed via ionization of the oxygen vacancy increased
the conductivity of the ZAZ films, thereby increasing the leakage current throughout the ZAZ films.
A Simulation Study on Reducing the Grain Boundary Position Dependency in Tunneling Thin-Film Transistors Using a Wide Tunneling Area
Authors: Kim Hyun-Min , Lee Junil , Choi Yunho , Lee Jong-Ho , Park Byung-Gook
Published: June 2020

In this paper, we confirmed the effect of the grain boundary position dependency on short channel poly-Si Tunneling TFTs using technology computer aided design (TCAD) simulation. The simulation results show that the grain boundary (GB) in the channel affects the tunneling barrier and
thus, produces variations in the electrical characteristics of the device such as the Vth and off-current. In the case of tunneling TFTs, the characteristics of the entire device are determined by the band to band tunneling (BTBT) currents occurring in very limited regions.
In this study, we proposed that a TFT device requires a wider BTBT region because this limited region worsens the variations in the electrical characteristics of the TFT device. Two additional methods were proposed, one using vertical BTBT over a wide area through an additional poly-Si layer
deposition and one widening the BTBT area through tilting implantation without an additional deposition process. The simulation results show that the variation of Vth is reduced to 10% through the extension of the BTBT area.
Effect of Graphene Thin Layer on a Static and Dynamic Magnetostrictive Behavior in TbDyFe Multi-Layered Film for Micro Energy Devices
Authors: Lee Heung-Shik
Published: June 2020

Magnetos-mechanical behaviors of TbDyFe/Graphene/TbDyFe film were compared with a tri-layered TbDyFe film to verify the effects of a graphene thin layer on the improvement of magnetic-mechanical performance, as well as decrease of dynamic response time under the low magnetic field.
Both of the Heisenberg model and Landau-Lifshitz-Gilbert equation were used to calculate the magnetic domain motion. Time consumptions were simulated to determine a uniformly magnetized state in Graphene and TbDyFe layers. To ensure the magnetostrictive characteristics, the magnetic moment
and the magnetostriction were measured using a fabricated magnetostrictive actuator. Compare to the three-layer TbDyFe films, TbDyFe/Graphene/TbDyFe showed a higher magnetostrictive behavior in response to low coercive forces in the range of 0 to 10 kA/m, even with the addition of low magnetic
fields. The dynamic magnetostriction response time was faster than the tri-layered TbDyFe film by approximately 24 millisecond.
Electrical and Optical Properties of Al-Doped ZnO Transparent Conductive Oxide Films Prepared via Radio Frequency Magnetron Co-Sputtering System
Authors: Joung Yeunho , Lee Kyumin , Park Mungi , Choi Wonseok
Published: June 2020

In this study, the optical and electrical properties of a transparent conductive oxide (TCO) film synthesized via the radio frequency (RF) magnetron co-sputtering of Al-doped ZnO (AZO) and ZnO targets on a glass substrate were investigated. In the visible region, the resistivity, transmittance,
and carrier concentration of the TCO film are influenced by the ratio of Al doping. The samples were prepared using two targets with the same deposition condition, except several different power levels on an AZO target to obtain different Al compositions in the film. The power range was 100–160
W in 20 W steps on the AZO target with a constant 50 W power level on the ZnO target. The electrical and optical characteristics of the film were measured using several apparatuses. The cross-section of the films was measured with via field emission scanning electron microscopy (FESEM) to
determine the thickness of the film. The electrical and optical properties of the AZO films were measured via Hall measurement and UV-visible spectroscopy. The structural characteristics of the AZO films were confirmed by Raman spectroscopy.
Local Electronic Structure of Calcite Investigated Using X-ray Absorption Spectroscopy at Different Span of Time
Authors: Singh Varsha , Singh Jitendra Pal , Shim Cheol-Hwee , Lee Sangsul , Chae Keun Hwa
Published: June 2020

For the present work, calcite nanoparticles was synthesized from calcium nitrate by annealing precursor at 300, 400, 500 and 600°C. Ca K-edge near edge X-ray absorption fine structure measurements revealed spectral features characteristics to the amorphous phase of calcium
carbonate at 300 and 400°C. At 500 and 600°C, the spectra were analogues to the calcite phase of calcium carbonate. Simulation of extended X-ray absorption fine structure spectra envisaged that both coordination number and bond distance for Ca–O bonds decreased with annealing
temperature. Both parameters attained values close to standard calcite when annealed at 600°C. The spectral features at Ca L-, O K- and C K-edge near edge X-ray absorption fine structure appeared at same positions for different ages, which envisaged the occurrence
of almost same local electronic structure for different span of times.
Enhanced Lithium Ion Storage by Titanium Dioxide Addition to Zinc Telluride-Based Alloy Composites
Authors: Nguyen Quoc Hanh , So Seongjoon , Hur Jaehyun
Published: June 2020

A nanostructured ZnTe–TiO2–C composite is synthesized, via a two-step high-energy mechanical milling process, for use as a new promising anode material in Li-ion batteries (LIBs). X-ray diffraction and X-ray photoelectron spectroscopy results confirm the successful
formation of ZnTe alloy and rutile TiO2 phases in the composites using ZnO, Te, Ti, and C as the starting materials. Scanning electron microscopy, transmission electron microscopy, and energy dispersive X-ray spectroscopy mapping measurements further reveal that ZnTe and TiO2
nanocrystals are uniformly dispersed in an amorphous carbon matrix. The electrochemical performances of ZnTe–TiO2–C and other control samples were investigated. Compared to ZnTe–TiO2 and ZnTe-C composites, the ZnTe– TiO2–C nanocomposite
exhibits better performance, thereby delivering a high reversible capacity of 561 mAh g−1 over 100 cycles and high rate capability at a high current density of 5 A g−1 (79% capacity retention of its capacity at 0.1 A g−1). Furthermore, the
long-term cyclic performance of ZnTe–TiO2–C at a current density of 0.5 A g−1 shows excellent reversible capacity of 528 mAh g−1 after 600 cycles. This improvement can be attributed to the presence of a TiO2-C hybrid matrix,
which acts as a buffering matrix that effectively mitigates the large volume changes of active ZnTe during repeated cycling. Overall, the ZnTe–TiO2–C nanocomposite is a potential candidate for high-performance anode materials in LIBs.
Free-Standing NiS2 Electrode as High-Rate Anode Material for Sodium-Ion Batteries
Authors: Sadan Milan K. , Kim Hui Hun , Kim Changhyeon , Cho Gyu-Bong , Reddy N. S. , Cho Kwon-Koo , Nam Tae-Hyun , Kim Ki-Won , Ahn Jou-Hyeon , Ahn Hyo-Jun
Published: June 2020

Owing to the speculated price hike and scarcity of lithium resources, sodium-ion batteries are attracting significant research interest these days. However, sodium-ion battery anodes do not deliver good electrochemical performance, particularly rate performance. Herein, we report the
facile electrospinning synthesis of a free-standing nickel disulfide (NiS2) embedded on carbon nanofiber. This electrode did not require a conducting agent, current collector, and binder, and typically delivered high capacity and rate performance. The electrode delivered a high
initial capacity of 603 mAh g−1 at the current density of 500 mA g−1. Moreover, the electrode delivered the capacity of 271 mAh g−1 at the high current density of 15 A g−1. The excellent rate performance and high coulombic
efficiency of the electrode were attributed to its low charge transfer resistance and unique structure.
Development of a Phosphor Screen with Mirror Coating to Improve Optical Properties in Radiography
Authors: Kim Kyo-Tae , Kim Joo-Hee , Lee Soon-Sung , Heo Ye-Ji , Cho Gyu-Seok , Choi, Sang-Hyoun , Mun Chi-Woong , Kim Kum-Bae
Published: June 2020

Phosphor screens have attracted increasing global interest because they can aid the acquisition of high-quality images while simultaneously reducing exposure. However, although increasing the thickness of the phosphor screen increases exposure efficiency due to scattered light, it also
leads to a broader light spread, which results in poorer resolution. Hence, in this study, we implemented a reflector using a mirror-coating technique on the surface of a phosphor screen and analyzed its characteristics in terms of luminescence intensity and resolution. We present the fabrication
and measurement of the phosphor screen based on a reflector containing Gd2O2S:Tb. The phosphor screen containing the reflector can be fabricated via the screen-printing method and roll-to-roll sputtering method. In particular, when compared to the condition without a
reflector, Al and Cu reflectors showed improvements in luminescence intensity of 15.7% and 12.2%, respectively, as well as lower full widths at half maximum of 11.45 and 9.08, respectively. This quantitatively demonstrates that Cu and Al are suitable reflector materials to improve exposure
efficiency while maintaining resolution in radiography systems. Moreover, because we did not utilize an optical assembly, which improves the transmission efficiency by matching the different refractive indices of the phosphor screen and photo-detector, we believe that the quantity of photons
could be further improved if the reflectors were applied to a commercial product. Thus, future studies using single-layer anti-reflector coating techniques with optical assemblies are warranted.
Investigation on the Electrochemical Properties of Antimony Tin Oxide Nanoparticle-Modified Graphene Aerogel as Cathode Matrix in Lithium–Sulfur Battery
Authors: Yan Yinglin , Lin Jiaming , Chen Shiyu , Zhang Shaoxiong , Yang Rong , Xu Yunhua , Han Tong
Published: June 2020

Lithium-sulfur (Li–S) batteries are considered the most appealing secondary batteries attributed to the ultrahigh theoretical specific capacity as 1675 mA·h·g−1 for elemental sulfur cathode. Nevertheless, there are still several disadvantages (sulfur
insulation, insoluble lithium polysulfide, shuttle effect, etc.) impeding the commercial application of Li–S batteries. Recent studies have discovered that nanosized metal oxides can effectively modify the electrochemical properties of composite cathodes in Li–S batteries. In this
paper, graphene aerogels (GA) loaded with different mass fractions of antimony tin oxide (ATO) nanoparticles were incorporated with sulfur and utilized as cathode materials for Li–S batteries. The sample (GA/ATO-3) loaded with 3 wt.% ATO nanoparticles showed the best electrochemical
performance. For example, the specific discharge capacity of first cycle reached 1210 mA·h·g−1 under a current of 0.1 C. The reversible discharge capacity was reduced to 545 mA·h·g−1 after 50 cycles, namely, the corresponding capacity
retention rate was approximately 50%. However, the coulombic efficiency was still near 100%. Potential modification mechanism was considered to be a combination between the GA with excellent conductivity, which effectively improved the internal conductivity of the cathode material, and the
ATO nanoparticles, which improved the distribution uniformity of the solid sulfur and its sulfurized product because the ATO nanoparticles acted as heterogeneous nucleation points. Furthermore, the ATO nanoparticles with strong polarity possessed a strong capture ability on the soluble polysulfide
ions. For the above reasons, the ATO-loaded GA cathode could effectively inhibit the “shuttle effect,” thereby, improved the electrochemical performance of Li–S batteries.
Potassium Oxalate as an Alternative Activating Reagent of Corn Starch-Derived Porous Carbons for Methane Storage
Authors: Lee Jong-Hoon , Park Soo-Jin
Published: June 2020

Fossil fuels are a main source of energy but also the major contributor to global warming. Therefore, the needs for alternative renewable and sustainable energy sources such as natural gas is increasing; nevertheless, for practical use, efficient gas storage materials of alternative
fuels are essential. Activated carbons (ACs) are a promising candidate as gas storage materials due to their narrow micropore size distribution and high porosity. Appropriate selection of the activating reagents is key factor for the preparation of high-performance ACs. Recently, potassium
hydroxide is the most widely used activating reagent, but its application for plant-scale production is reluctant by its toxicity and high corrosiveness. Hence, in this study, the less corrosive and easy manageable potassium oxalate salt was used as an alternative reagent to prepare ACs from
corn starch, for methane storage. The products were characterized based on their N2 adsorption–desorption isotherms at 77 K and on their specific surface area and pore size distributions, respectively calculated via the Brunauer–Emmett–Teller (BET) equation and
the non-local density functional (NLDFT) theory. The methane storage capacities and adsorption cycles were investigated with a high-pressure adsorption instrument operating at 298 K and 35 bar.
Structural and Electrical Properties of K(Ta, Nb)O3 Thin Films with the Variation of Sintering Temperature
Authors: Kim Ji-Won , Lee Sung-Gap , Kim Kyeong-Min , Yuk Ji-Su , Park Joo-Seok
Published: June 2020

In this study, KTa0.55Nb0.45O3 (KTN) thin films were manufactured by using Chemical Solution Deposition (CSD) method with variations in the sintering temperature and were investigated in order to apply their applicability in memory devices. The KTN thin
films were made after coating the PZT bufferlayer on Pt/Ti/SiO2/Si substrate. Each layer was dried at 200°C for 5 min to remove any organic materials and pyrolyzed at 400°C for 10 min. Finally, the layers were sintered for 30 min under an oxygen atmosphere, respectively.
The pattern of KTN thin films showed a preference to the (100) and (200) orientations. Also, an increase in the sintering temperature caused the KTN crystalline peak intensities to also increase. When looking at the results from the Scanning Electron Microscope and Atomic Force Microscope
data, the average grain size and root mean square roughness (Rrms) of KTN thin films were 109~157 nm and about 4 nm, respectively. Typical dielectric dispersion characteristics were observed in which the dielectric constant decreases with an increase of the applied frequency.
The specimen sintered at 750°C showed the highest dielectric constant of 769 at 1 kHz.
Determination of Stark Shifts and Widths Using Time Resolved Laser-Induced Breakdown Spectroscopy (LIBS) Measurements
Authors: Kumar Prashant , Soumyashree Swetapuspa , Rao Epuru Nageswara , Banerjee Swaroop B. , Singh R. P. , Subramanian K. P.
Published: June 2020

Stark broadening parameters have been estimated for resonant lines of Al(I) using time resolved measurements. The relation between the various emission line characteristics at different phases of opacity have been utilized to obtain the value of plasma temperature and Stark width parameters from the experimental data. The observed value of the center line intensity and Lorentzian component of the line width are compared against a simulated value of these parameters for optically thin case. The plasma temperature and Stark broadening parameters are obtained for the best fit condition by matching the experimentally observed and the simulated values of intensity and line widths. The time resolved measurements result in much better estimates for Stark parameters by allowing multiple points for fitting keeping the number of variables limited. The Stark shift parameters are also obtained from the slope of the plot of observed central wavelength shifts versus observed electron number density which is measured as a function of time. Hence, a method utilizing multiple-time observation data to obtain the Stark broadening parameters for lines showing self-absorption has been demonstrated.