bluuebunny/crossref_metadata_2025 huggingface dataset:
A Pediatric Cardiology Fellowship Boot Camp improves trainee confidence
Authors: Allan Catherine K. , Tannous Paul , DeWitt Elizabeth , Farias Michael , Mansfield Laura , Ronai Christina , Schidlow David , Sanders Stephen P. , Lock James E. , Newburger Jane W. , Brown David W.
Published: February 2017

Introduction

New paediatric cardiology trainees are required to rapidly assimilate knowledge and gain clinical skills to which they have limited or no exposure during residency. The Pediatric Cardiology Fellowship Boot Camp (PCBC) at Boston Children’s Hospital was designed to provide incoming fellows with an intensive exposure to congenital cardiac pathology and a broad overview of major areas of paediatric cardiology practice.

Methods

The PCBC curriculum was designed by core faculty in cardiac pathology, echocardiography, electrophysiology, interventional cardiology, exercise physiology, and cardiac intensive care. Individual faculty contributed learning objectives, which were refined by fellowship directors and used to build a programme of didactics, hands-on/simulation-based activities, and self-guided learning opportunities.

Results

A total of 16 incoming fellows participated in the 4-week boot camp, with no concurrent clinical responsibilities, over 2 years. On the basis of pre- and post-PCBC surveys, 80% of trainees strongly agreed that they felt more prepared for clinical responsibilities, and a similar percentage felt that PCBC should be offered to future incoming fellows. Fellows showed significant increase in their confidence in all specific knowledge and skills related to the learning objectives. Fellows rated hands-on learning experiences and simulation-based exercises most highly.

Conclusions

We describe a novel 4-week-long boot camp designed to expose incoming paediatric cardiology fellows to the broad spectrum of knowledge and skills required for the practice of paediatric cardiology. The experience increased trainee confidence and sense of preparedness to begin fellowship-related responsibilities. Given that highly interactive activities were rated most highly, boot camps in paediatric cardiology should strongly emphasise these elements.
Notch activation enhances mesenchymal stem cell sheet osteogenic potential by inhibition of cellular senescence
Authors: Tian Ye , Xu Ying , Xue Taiyang , Chen Longgang , Shi Bin , Shu Bing , Xie Chao , Max Morandi Massimo , Jaeblon Todd , Marymont John V , Dong Yufeng
Published: February 2017

Our previous studies have confirmed the therapeutic effects of mesenchymal stem cell (MSC) monolayer sheet transplantation on allograft repair. A limiting factor in their application is the loss of MSC multi-potency as a result of high density sheet culture-induced senescence. In the study reported in this article, we tested whether Notch activation could be used to prevent or delay sheet culture-induced cell aging. Our results showed that, during in vitro long-term (5-day) cell sheet culture, MSCs progressively lose their progenitor characteristics. In contrast, Notch activation by Jagged1 in MSC sheet culture showed reduced cellular senescence and cell cycle arrest compared with control MSCs without Notch activation. Importantly, knockdown of Notch target gene Hes1 totally blocked the inhibition effect of Jagged1 on cellular senescence. Finally, the in vivo allograft transplantation data showed a significant enhanced callus formation and biomechanical properties in Notch activation cultured long-term sheet groups when compared with long-term cultured sheet without Notch activation. Our results suggest that Notch activation by Jagged1 could be used to overcome the stem cell aging caused by high density sheet culture, thereby increasing the therapeutic potential of MSC sheets for tissue regeneration.
Adipocytes activate mitochondrial fatty acid oxidation and autophagy to promote tumor growth in colon cancer
Authors: Wen Yang-An , Xing Xiaopeng , Harris Jennifer W , Zaytseva Yekaterina Y , Mitov Mihail I , Napier Dana L , Weiss Heidi L , Mark Evers B , Gao Tianyan
Published: February 2017

Obesity has been associated with increased incidence and mortality of a wide variety of human cancers including colorectal cancer. However, the molecular mechanism by which adipocytes regulate the metabolism of colon cancer cells remains elusive. In this study, we showed that adipocytes isolated from adipose tissues of colon cancer patients have an important role in modulating cellular metabolism to support tumor growth and survival. Abundant adipocytes were found in close association with invasive tumor cells in colon cancer patients. Co-culture of adipocytes with colon cancer cells led to a transfer of free fatty acids that released from the adipocytes to the cancer cells. Uptake of fatty acids allowed the cancer cells to survive nutrient deprivation conditions by upregulating mitochondrial fatty acid β-oxidation. Mechanistically, co-culture of adipocytes or treating cells with fatty acids induced autophagy in colon cancer cells as a result of AMPK activation. Inhibition of autophagy attenuated the ability of cancer cells to utilize fatty acids and blocked the growth-promoting effect of adipocytes. In addition, we found that adipocytes stimulated the expression of genes associated with cancer stem cells and downregulated genes associated with intestinal epithelial cell differentiation in primary colon cancer cells and mouse tumor organoids. Importantly, the presence of adipocytes promoted the growth of xenograft tumors in vivo. Taken together, our results show that adipocytes in the tumor microenvironment serve as an energy provider and a metabolic regulator to promote the growth and survival of colon cancer cells.
Tissue transglutaminase (TG2) enables survival of human malignant pleural mesothelioma cells in hypoxia
Authors: Zonca Sara , Pinton Giulia , Wang Zhuo , Soluri Maria Felicia , Tavian Daniela , Griffin Martin , Sblattero Daniele , Moro Laura
Published: February 2017

Malignant pleural mesothelioma (MPM) is an aggressive tumor linked to environmental/occupational exposure to asbestos, characterized by the presence of significant areas of hypoxia. In this study, we firstly explored the expression and the role of transglutaminase 2 (TG2) in MPM cell adaptation to hypoxia. We demonstrated that cells derived from biphasic MPM express the full-length TG2 variant at higher levels than cells derived from epithelioid MPM and normal mesothelium. We observed a significant induction of TG2 expression and activity when cells from biphasic MPM were grown as a monolayer in chronic hypoxia or packed in spheroids, where the presence of a hypoxic core was demonstrated. We described that the hypoxic induction of TG2 was HIF-2 dependent. Importantly,TGM2-v1silencing caused a marked and significant reduction of MPM cell viability in hypoxic conditions when compared with normoxia. Notably, a TG2-selective irreversible inhibitor that reacts with the intracellular active form of TG2, but not a non-cell-permeable inhibitor, significantly compromised cell viability in MPM spheroids. Understanding the expression and function of TG2 in the adaptation to the hypoxic environment may provide useful information for novel promising therapeutic options for MPM treatment.
Berbamine postconditioning protects the heart from ischemia/reperfusion injury through modulation of autophagy
Authors: Zheng Yanjun , Gu Shanshan , Li Xuxia , Tan Jiliang , Liu Shenyan , Jiang Yukun , Zhang Caimei , Gao Ling , Yang Huang-Tian
Published: February 2017

Pretreatment of berbamine protects the heart from ischemia/reperfusion (I/R) injury. However it is unknown whether it has cardioprotection when given at the onset of reperfusion (postconditioning (PoC)), a protocol with more clinical impact. Autophagy is upregulated in I/R myocardium and exacerbates cardiomyocyte death during reperfusion. However, it is unknown whether the autophagy during reperfusion is regulated by berbamine. Here we investigated whether berbamine PoC (BMPoC) protects the heart through regulation of autophagy by analyzing the effects of BMPoC on infarct size and/or cell death, functional recovery and autophagy in perfused rat hearts and isolated cardiomyocytes subjected to I/R. Berbamine from 10 to 100 nM given during the first 5 min of reperfusion concentration-dependently improved post-ischemic myocardial function and attenuated cell death. Similar protections were observed in cardiomyocytes subjected to simulated I/R. Meanwhile, BMPoC prevented I/R-induced impairment of autophagosome processing in cardiomyocytes, characterized by increased LC3-II level and GFP-LC3 puncta, and decreased p62 degradation. Besides, lysosomal inhibitor chloroquine did not induce additional increase of LC3-II and P62 abundance after I/R but it reversed the effects of BMPoC in those parameters in cardiomyocytes, suggesting that I/R-impaired autophagic flux is restored by BMPoC. Moreover, I/R injury was accompanied by enhanced expression of Beclin 1, which was significantly inhibited by BMPoC. In vitro and in vivo adenovirus-mediated knockdown of Beclin 1 in myocardium and cardiomyocytes restored I/R-impaired autophagosome processing, associated with an improvement of post-ischemic recovery of myocardial contractile function and a reduction of cell death, but it did not have additive effects to BMPoC. Conversely, overexpression of Beclin 1 abolished the cardioprotection of BMPoC as did by overexpression of an essential autophagy gene Atg5. Furthermore, BMPoC-mediated cardioprotection was abolished by a specific Akt1/2 inhibitor A6730. Our results demonstrate that BMPoC confers cardioprotection by modulating autophagy during reperfusion through the activation of PI3K/Akt signaling pathway.
De novo hybrid assembly of the rubber tree genome reveals evidence of paleotetraploidy in Hevea species
Authors: Pootakham Wirulda , Sonthirod Chutima , Naktang Chaiwat , Ruang-Areerate Panthita , Yoocha Thippawan , Sangsrakru Duangjai , Theerawattanasuk Kanikar , Rattanawong Ratchanee , Lekawipat Napawan , Tangphatsornruang Sithichoke
Published: February 2017

Para rubber tree (Hevea brasiliensis) is an important economic species as it is the sole commercial producer of high-quality natural rubber. Here, we report a de novo hybrid assembly of BPM24 accession, which exhibits resistance to major fungal pathogens in Southeast Asia. Deep-coverage 454/Illumina short-read and Pacific Biosciences (PacBio) long-read sequence data were acquired to generate a preliminary draft, which was subsequently scaffolded using a long-range “Chicago” technique to obtain a final assembly of 1.26 Gb (N50 = 96.8 kb). The assembled genome contains 69.2% repetitive sequences and has a GC content of 34.31%. Using a high-density SNP-based genetic map, we were able to anchor 28.9% of the genome assembly (363 Mb) associated with over two thirds of the predicted protein-coding genes into rubber tree’s 18 linkage groups. These genetically anchored sequences allowed comparative analyses of the intragenomic homeologous synteny, providing the first concrete evidence to demonstrate the presence of paleotetraploidy in Hevea species. Additionally, the degree of macrosynteny conservation observed between rubber tree and cassava strongly supports the hypothesis that the paleotetraploidization event took place prior to the divergence of the Hevea and Manihot species.
Construction of a guide-RNA for site-directed RNA mutagenesis utilising intracellular A-to-I RNA editing
Authors: Fukuda Masatora , Umeno Hiromitsu , Nose Kanako , Nishitarumizu Azusa , Noguchi Ryoma , Nakagawa Hiroyuki
Published: February 2017

As an alternative to DNA mutagenesis, RNA mutagenesis can potentially become a powerful gene-regulation method for fundamental research and applied life sciences. Adenosine-to-inosine (A-to-I) RNA editing alters genetic information at the transcript level and is an important biological process that is commonly conserved in metazoans. Therefore, a versatile RNA-mutagenesis method can be achieved by utilising the intracellular RNA-editing mechanism. Here, we report novel guide RNAs capable of inducing A-to-I mutations by guiding the editing enzyme, human adenosine deaminase acting on RNA (ADAR). These guide RNAs successfully introduced A-to-I mutations into the target-site, which was determined by the reprogrammable antisense region. In ADAR2-over expressing cells, site-directed RNA editing could also be performed by simply introducing the guide RNA. Our guide RNA framework provides basic insights into establishing a generally applicable RNA-mutagenesis method.
Quercetin Inhibits Inflammasome Activation by Interfering with ASC Oligomerization and Prevents Interleukin-1 Mediated Mouse Vasculitis
Authors: Domiciano Talita P. , Wakita Daiko , Jones Heather D. , Crother Timothy R. , Verri Waldiceu A. , Arditi Moshe , Shimada Kenichi
Published: February 2017

Interleukin-1β (IL-1β) is a highly inflammatory cytokine that significantly contributes to both acute and chronic inflammatory diseases. The secretion of IL-1β requires a unique protease, caspase-1, which is activated by various protein platforms called inflammasomes. Data suggests a key role for mitochondrial reactive oxygen species for inflammasome activation. Flavonoids constitute a group of naturally occurring polyphenolic molecules with many biological activities, including antioxidant effects. In this study, we investigated the effect of three flavonoids, quercetin (QUC), naringenin, and silymarim on inflammasome activation. We found that QUC inhibits IL-1β secretion by both the NLRP3 and AIM2 inflammasome in a dose dependent manner, but not the NLRC4 inflammasome. QUC inhibition of the inflammasome was still observed in Atg16l1 knockout macrophages, indicating that QUC’s effect was autophagy independent. Since QUC inhibited both NLRP3 and AIM2 inflammasomes but not NLRC4, we assessed ASC speck formation. QUC reduced ASC speck formation and ASC oligomerization compared with controls. Additionally, QUC inhibited IL-1β in Cryopyrin-Associated Periodic Syndromes (CAPS) macrophages, where NLRP3 inflammasome is constitutively activated. In conclusion, QUC inhibits both the NLRP3 and AIM2 inflammasome by preventing ASC oligomerization and may be a potential therapeutic candidate for Kawasaki disease vasculitis and other IL-1 mediated inflammatory diseases.
Structural Connectivity Variances Underlie Functional and Behavioral Changes During Pain Relief Induced by Neuromodulation
Authors: Lin Richard L. , Douaud Gwenaëlle , Filippini Nicola , Okell Thomas W. , Stagg Charlotte J. , Tracey Irene
Published: February 2017

An increased understanding of the relationship between structural connections and functional and behavioral outcomes is an essential but under-explored topic in neuroscience. During transcranial direct current stimulation (tDCS)–induced analgesia, neuromodulation occurs through a top-down process that depends on inter-regional connections. To investigate whether variation in anatomical connectivity explains functional and behavorial outcomes during neuromodulation, we first combined tDCS and a tonic pain model with concurrent arterial spin labelling that measures cerebral perfusion related to ongoing neural activity. Left dorsolateral prefrontal cortex (L-DLPFC) tDCS induced an analgesic effect, which was explained by reduced perfusion to posterior insula and thalamus. Second, we used diffusion imaging to assess white matter structural integrity between L-DLPFC and thalamus, two key components of the neuromodulatory network. Fractional anisotropy of this tract correlated positively with functional and behavioral modulations. This suggests structural dependence by the neuromodulatory process to induce analgesia with potential relevance for patient stratification.
Discovery of a very Lyman-α-luminous quasar at z = 6.62
Authors: Koptelova Ekaterina , Hwang Chorng-Yuan , Yu Po-Chieh , Chen Wen-Ping , Guo Jhen-Kuei
Published: February 2017

Distant luminous quasars provide important information on the growth of the first supermassive black holes, their host galaxies and the epoch of reionization. The identification of quasars is usually performed through detection of their Lyman-αline redshifted to "Equation missing"0.9 microns at z > 6.5. Here, we report the discovery of a very Lyman-αluminous quasar, PSO J006.1240 + 39.2219 at redshift z = 6.618, selected based on its red colour and multi-epoch detection of the Lyman-αemission in a single near-infrared band. The Lyman-αline luminosity of PSO J006.1240 + 39.2219 is unusually high and estimated to be 0.8 × 1012Solar luminosities (about 3% of the total quasar luminosity). The Lyman-αemission of PSO J006.1240 + 39.2219 shows fast variability on timescales of days in the quasar rest frame, which has never been detected in any of the known high-redshift quasars. The high luminosity of the Lyman-αline, its narrow width and fast variability resemble properties of local Narrow-Line Seyfert 1 galaxies which suggests that the quasar is likely at the active phase of the black hole growth accreting close or even beyond the Eddington limit.
Creation of Pd/Al2O3 Catalyst by a Spray Process for Fixed Bed Reactors and Its Effective Removal of Aqueous Bromate
Authors: Gao Yu , Sun Wuzhu , Yang Weiyi , Li Qi
Published: February 2017

Palladium nanoparticles were grown on sub-millimeter activated Al2O3 particle support by spraying H2PdCl4 solution evenly onto the support, followed with a thermal reduction under H2 atmosphere. Compared with its counterpart created by the conventional impregnation method, the Pd/Al2O3 catalyst created by the spray process could enrich the existence of active Pd nanoparticles on the surface of the catalyst support and increase their degree of dispersion, resulting in a much higher activity in the catalytic reduction of bromate in water. The effect of Al2O3 support particle size on the bromate removal rate was also investigated, which demonstrated that smaller support particle size could have higher activity in the catalytic reduction of bromate in water because of its larger exposed surface. This Pd/Al2O3 catalyst could be easily used in the fixed bed reactor due to its large support size and demonstrated excellent stability in the catalytic reduction of bromate in mineral water. This Pd/Al2O3 catalyst also exhibited a good catalytic reduction performance on azo dyes as demonstrated by its effective catalytic hydrogenation of methyl orange. Thus, catalysts prepared by the spray method developed in this work could have the potential to be used in fixed bed reactors for various water treatment practices.
Generation of a bile salt export pump deficiency model using patient-specific induced pluripotent stem cell-derived hepatocyte-like cells
Authors: Imagawa Kazuo , Takayama Kazuo , Isoyama Shigemi , Tanikawa Ken , Shinkai Masato , Harada Kazuo , Tachibana Masashi , Sakurai Fuminori , Noguchi Emiko , Hirata Kazumasa , Kage Masayoshi , Kawabata Kenji , Sumazaki Ryo , Mizuguchi Hiroyuki
Published: February 2017

Bile salt export pump (BSEP) plays an important role in hepatic secretion of bile acids and its deficiency results in severe cholestasis and liver failure. Mutation of the ABCB11 gene encoding BSEP induces BSEP deficiency and progressive familial intrahepatic cholestasis type 2 (PFIC2). Because liver transplantation remains standard treatment for PFIC2, the development of a novel therapeutic option is desired. However, a well reproducible model, which is essential for the new drug development for PFIC2, has not been established. Therefore, we attempted to establish a PFIC2 model by using iPSC technology. Human iPSCs were generated from patients with BSEP-deficiency (BD-iPSC), and were differentiated into hepatocyte-like cells (HLCs). In the BD-iPSC derived HLCs (BD-HLCs), BSEP was not expressed on the cell surface and the biliary excretion capacity was significantly impaired. We also identified a novel mutation in the 5′-untranslated region of the ABCB11 gene that led to aberrant RNA splicing in BD-HLCs. Furthermore, to evaluate the drug efficacy, BD-HLCs were treated with 4-phenylbutyrate (4PBA). The membrane BSEP expression level and the biliary excretion capacity in BD-HLCs were rescued by 4PBA treatment. In summary, we succeeded in establishing a PFIC2 model, which may be useful for its pathophysiological analysis and drug development.
Field background odour should be taken into account when formulating a pest attractant based on plant volatiles
Authors: Cai Xiaoming , Bian Lei , Xu Xiuxiu , Luo Zongxiu , Li Zhaoqun , Chen Zongmao
Published: February 2017

Attractants for pest monitoring and controlling can be developed based on plant volatiles. Previously, we showed that tea leafhopper (Empoasca onukii) preferred grapevine, peach plant, and tea plant odours to clean air. In this research, we formulated three blends with similar attractiveness to leafhoppers as peach, grapevine, and tea plant volatiles; these blends were composed of (Z)-3-hexenyl acetate, (E)-ocimene, (E)-4,8-dimethyl-1,3,7-nonatriene, benzaldehyde, and ethyl benzoate. Based on these five compounds, we developed two attractants, formula-P and formula-G. The specific component relative to tea plant volatiles in formula-P was benzaldehyde, and that in formula-G was ethyl benzoate. These two compounds played a role in attracting leafhoppers. In laboratory assays, the two attractants were more attractive than tea plant volatiles to the leafhoppers, and had a similar level of attractiveness. However, the leafhoppers were not attracted to formula-P in the field. A high concentration of benzaldehyde was detected in the background odour of the tea plantations. In laboratory tests, benzaldehyde at the field concentration was attractive to leafhoppers. Our results indicate that the field background odour can interfere with a point-releasing attractant when their components overlap, and that a successful attractant must differ from the field background odour.
Astragaloside IV ameliorates 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis implicating regulation of energy metabolism
Authors: Jiang Xu-Guang , Sun Kai , Liu Yu-Ying , Yan Li , Wang Ming-Xia , Fan Jing-Yu , Mu Hong-Na , Li Chong , Chen Yuan-Yuan , Wang Chuan-She , Han Jing-Yan
Published: February 2017

Dysfunction of energy metabolism is involved in inflammatory bowel disease (IBD). This study was designed to investigate the potential of astragaloside IV (ASIV), an active ingredient ofRadix Astragalus, to ameliorate colonic mucosal injury, with focusing on the implication of energy restoration in the underlying mechanism. Experimental colitis model was established in rats by injecting 2,4,6-trinitrobenzene sulfonic acid (TNBS) through anus. After 24 hours, ASIV was administrated once daily by gavage for 6 days. On day 1 and day 7, colon tissue was collected for macroscopic and histological examination, ELISA, Western blot and immunohistochemical analysis. TNBS impaired colonic mucosa with an injured epithelial architecture, increased inflammatory cell infiltration, and decreased colonic blood flow. Lgr5 positive cell number in crypt and β-catenin nuclear translocation were down-regulated by TNBS treatment. TNBS induced epithelial F-actin disruption and junctional protein degradation. Furthermore, adenosine triphosphate (ATP) content and ATP synthase subunit β expression in the colon tissue were significantly decreased after TNBS stimulation. All of the aforementioned alterations were relieved by ASIV post-treatment. The present study revealed that ASIV promoted mucosal healing process in TNBS-induced colitis, which was most likely attributed to regulating energy metabolism.
An inhibitory role of Arg-84 in anion channelrhodopsin-2 expressed in Escherichia coli
Authors: Doi Satoko , Tsukamoto Takashi , Yoshizawa Susumu , Sudo Yuki
Published: February 2017

Anion channelrhodopsin-2 (ACR2) was recently identified from the cryptophyte algae Guillardia theta and has become a focus of interest in part because of its novel light-gated anion channel activity and its extremely high neural silencing activity. In this study, we tried to express ACR2 in Escherichia coli cells as a recombinant protein. The E. coli cells expressing ACR2 showed an increase in pH upon blue-light illumination in the presence of monovalent anions and the protonophore carbonyl cyanide m-chlorophenylhydrazone (CCCP), indicating an inward anion channel activity. Then, taking advantage of the E. coli expression system, we performed alanine-scanning mutagenesis on conserved basic amino acid residues. One of them, R84A, showed strong signals compared with the wild-type, indicating an inhibitory role of R84 on Cl− transportation. The signal was strongly enhanced in R84E, whereas R84K was less effective than the wild-type (i.e., R84). These results suggest that the positive charge at position 84 is critical for the inhibition. Thus we succeeded in functional expression of ACR2 in E. coli and found the inhibitory role of R84 during the anion transportation.
Exploiting aerosol dilution for the determination of ultra-trace elements in honey by collision/reaction cell inductively coupled plasma mass spectrometry (CRC-ICP-MS) without thermal digestion
Authors: Döker Serhat
Published: February 2017

A rapid dilute-and-shoot procedure was described for the ultra-trace determination of Li, Al, Cr, Mn, Co, Ni, Cu, Zn, As, Cd, Tl, Pb and U in honey by collision/reaction cell inductively coupled plasma mass spectrometry (CRC-ICP-MS).
Direct speciation of Cr in drinking water by in situ thermal separation ETAAS
Authors: Cui Hao , Guo Wei , Jin Lanlan , Guo Qinghai , Hu Shenghong
Published: February 2017

Evaluation of anin situthermal separation ETAAS method for the direct determination of Cr species was carried out.
Nanograined surface shell wall controlled ZnO–ZnS core–shell nanofibers and their shell wall thickness dependent visible photocatalytic properties
Authors: Ranjith Kuglaur Shanmugam , Senthamizhan Anitha , Balusamy Brabu , Uyar Tamer
Published: February 2017

The core–shell form of ZnO–ZnS based heterostructural nanofibers (NF) has received increased attention for use as a photocatalyst owing to its potential for outstanding performance under visible irradiation.
A fluorescent chemosensor for Sn2+ and Cu2+ based on a carbazole-containing diarylethene
Authors: Qu Shengzu , Zheng Chunhong , Liao Guanming , Fan Congbin , Liu Gang , Pu Shouzhi
Published: February 2017

A carbazole-containing diarylethene was synthesized. Its fluorescence was enhanced and quenched, respectively, upon addition of Sn2+ and Cu2+ over other cations. Moreover, the compound can be applied to detect Sn2+ and Cu2+ in natural water sample.
Correlation between photoluminescence spectra with gas sensing and photocatalytic activities in hierarchical ZnO nanostructures
Authors: Thu Do T. Anh , Giang Ho Truong , Van Huong Do , Ngan Pham Quang , Thai Giang Hong , Thu Do Thi , Lam Tran Dai
Published: February 2017

We synthesized ZnO architectures, including nanorods, porous plates, and flower-like architectures by using different types of zinc salts and surfactants in a hydrothermal process.
Synthesis, mechanism and efficient modulation of a fluorescence dye by photochromic pyrazolone with energy transfer in the crystalline state
Authors: Li Yinhua , Guo Jixi , Liu Anjie , Jia Dianzeng , Wu Xueyan , Chen Yi
Published: February 2017

The emission intensity of DPA can be efficiently switched by fluorescence resonance energy transfer between the energy donor DPA and acceptor 1b.
Highlighting diffusional coupling effects in zeolite catalyzed reactions by combining the Maxwell–Stefan and Langmuir–Hinshelwood formulations
Authors: Krishna Rajamani , Baur Richard , van Baten Jasper M.
Published: February 2017

The combined phenomena of intra-crystalline adsorption, diffusion and reversible chemical reactions inside microporous crystalline zeolite catalyst particles are described by combining the Langmuir–Hinshelwood kinetics with the Maxwell–Stefan (M–S) diffusion formulation.
Low mutual coupling antenna array for WLAN application
Authors: Sun Xu‐bao , Cao Mao Yong
Published: February 2017

A mutual coupling reduction antenna design for WLAN MIMO application is proposed. The proposed antenna array consists of two rectangular patch antennas, six parallel metal strips, a single substrate layer, and common ground plane. About −42 dB mutual coupling is achieved at the 5.8 GHz resonant frequency. Both simulation and measurement results confirm improvements in mutual coupling at about 30 dB when compared with those without metal strips. The radiation patterns are almost unaffected by adding these metal strips in the proposed antenna.
Capacity analysis of α − η − μ channels over different adaptive transmission protocols
Authors: Aldalgamouni Taimour , Magableh Amer M. , Mater Sharaf , Badarneh Osamah Sami
Published: February 2017

In this study, the authors consider the α − η − μ fading channels and derive a new form for the cumulative distribution function of the signal‐to‐noise ratio (SNR) in terms of the bivariate Fox H‐function. They also derive closed‐form expressions for the moments and the amount of fading of the SNR. The capacity of α − η − μ fading channels is analysed assuming different adaptive transmission protocols. To this end, they provide analytical closed‐form expressions for the average channel capacity with optimal rate adaptation (CORA), optimal power and rate adaptation (COPRA), channel inversion with fixed rate (CIFR) (CCIFR), and truncated CIFR (CTIFR). The derived expressions are valid for arbitrary values of the α, η, and μ fading parameters. The derived expressions can also be reduced to study the capacity of other fading distributions such as η − μ, α − μ, Weibull, and Nakagami. Numerical results are provided and compared with simulations to validate of the derived expressions.
Improving capacity for physical network coding with lattice strategies in two‐way fading channels
Authors: Zhan Ao , Wu Chengyu , Shi Qingjiang , Xu Weiqiang
Published: February 2017

In this study, the capacity problem in a two‐way fading channel is considered. The authors propose amplify‐and‐forward with lattice codes (AF&LC), exploiting a modulo operation at the relay. Without destroying the construct of codebook, the modulo operation reduces the power of the received signals, and thus achieves a larger power‐scaled gain than the amplified‐and‐forward with random codes (AF&RC). It is proved that AF&LC outperforms AF&RC in the high signal‐to‐noise ratio (SNR) regime by employing theoretical analyses. By simulating one‐dimension lattice codes, AF&LC achieves about 1.5 dB SNR gain over AF&RC with error probability 10−2. Compared with decode‐and‐forward with lattice codes (DF&LC) and fixed modulo‐and‐forward (FMF), AF&LC achieves larger rate region which is closer to upper bound in some scenarios. Moreover, AF&LC can work in fading two‐way channels without feedback schemes, which is easier to be implemented than DF&LC, FMF and compress‐and‐forward.
Invited Article: Acousto-optic finite-difference frequency-domain algorithm for first-principles simulations of on-chip acousto-optic devices
Authors: Shi Yu , Cerjan Alexander , Fan Shanhui
Published: February 2017

We introduce a finite-difference frequency-domain algorithm for coupled acousto-optic simulations. First-principles acousto-optic simulation in time domain has been challenging due to the fact that the acoustic and optical frequencies differ by many orders of magnitude. We bypass this difficulty by formulating the interactions between the optical and acoustic waves rigorously as a system of coupled nonlinear equations in frequency domain. This approach is particularly suited for on-chip devices that are based on a variety of acousto-optic interactions such as the stimulated Brillouin scattering. We validate our algorithm by simulating a stimulated Brillouin scattering process in a suspended waveguide structure and find excellent agreement with coupled-mode theory. We further provide an example of a simulation for a compact on-chip resonator device that greatly enhances the effect of stimulated Brillouin scattering. Our algorithm should facilitate the design of nanophotonic on-chip devices for the harnessing of photon-phonon interactions.
Duffin–Kemmer–Petiau oscillator with Snyder-de Sitter algebra
Authors: Falek M. , Merad M. , Birkandan T.
Published: February 2017

We present an exact solution of the one-dimensional Bosonic oscillator for spin 1 and spin 0 particles with the Snyder-de Sitter model, where the energy eigenvalues and eigenfunctions are determined for both cases. The wave functions can be given in terms of Gegenbauer polynomials. We also comment on the thermodynamic properties of the system.
pK
a
of Glu325 in LacY
Authors: Grytsyk Natalia , Sugihara Junichi , Kaback H. Ronald , Hellwig Petra
Published: February 2017

Significance

The pK
a
of Glu325 in the lactose permease is very alkaline, and protonation is essential for effective binding of galactopyranosides because a negative charge at this position is incompatible with binding. Thus, Glu325 plays a central role in “coupling.”
Antifouling property of micro-arc oxidation coating incorporating Cu2O nanoparticles on Ti6Al4V
Authors: Zhao Dan , Lu Yuhui , Zeng Xing , Wang Zhong , Liu Shaogang , Wang Tao
Published: February 2017

To reduce the overgrowth of marine organisms on titanium alloy, this paper presents an antifouling scheme to process ceramic coatings on Ti6Al4V (TC4) using micro-arc oxidation (MAO) combined with nanotechnology. In the study, different concentrations of Cu2O nanoparticles are added into the electrolytes prepared for MAO process to produce the ceramic coatings. The antifouling performances of the samples are observed by scanning election microscope (SEM), energy dispersive spectrometer and X-ray diffraction. The results demonstrate that nanoparticles of Cu2O are found in the coating films and the antifouling performance of titanium alloy after MAO treatment is obviously enhanced, in which antibacterial rate is up to 95.25%. The Ti-MAO-10.0g/LCu2O group has the highest antibacterial rate of 99.74%.
Path dependency and convergence of three worlds of welfare policy during the Great Recession: UK, Germany and Sweden
Authors: Kiess Johannes , Norman Ludvig , Temple Luke , Uba Katrin
Published: February 2017

This paper investigates policy responses to the Great Recession in Sweden, the United Kingdom and Germany. Faced with the global financial crisis in 2007, responses in the respective countries differed considerably and followed the “old” paths of their institutional legacies. We focus on labour market and social welfare policies and demonstrate how these differing responses were shaped by path-dependent ideational paradigms. Since these paradigms are first and foremost carried by policy communities, the analysis does not, in contrast to prior studies, only rely on policy documents but outlines the process as seen from the perspective of key public officials and experts in the respective fields. The paper shows how the crisis was perceived and which kinds of arguments were used for explaining the liberal (UK), conservative (Germany) and social–democratic (Sweden) responses to crisis.
Calcium signals drive cell shape changes during zebrafish midbrain–hindbrain boundary formation
Authors: Sahu Srishti U. , Visetsouk Mike R. , Garde Ryan J. , Hennes Leah , Kwas Constance , Gutzman Jennifer H.
Published: February 2017

One of the first morphogenetic events in the vertebrate brain is the formation of the highly conserved midbrain–hindbrain boundary (MHB). Specific cell shape changes occur at the point of deepest constriction of the MHB, the midbrain–hindbrain boundary constriction (MHBC), and are critical for proper MHB formation. These cell shape changes are controlled by nonmuscle myosin II (NMII) motor proteins, which are tightly regulated via the phosphorylation of their associated myosin regulatory light chains (MRLCs). However, the upstream signaling pathways that initiate the regulation of NMII to mediate cell shape changes during MHB morphogenesis are not known. We show that intracellular calcium signals are critical for the regulation of cell shortening during initial MHB formation. We demonstrate that the MHB region is poised to respond to calcium transients that occur in the MHB at the onset of MHB morphogenesis and that calcium mediates phosphorylation of MRLC specifically in MHB tissue. Our results indicate that calmodulin 1a (calm1a), expressed specifically in the MHB, and myosin light chain kinase together mediate MHBC cell length. Our data suggest that modulation of NMII activity by calcium is critical for proper regulation of cell length to determine embryonic brain shape during development.
Impact of technological creep on fishing effort and fishing mortality, for a selection of European fleets
Authors: Marchal Paul , Andersen Bo , Caillart B. , Eigaard Ole , Guyader Olivier , Hovgaard Holger , Iriondo Ane , Le Fur Fanny , Sacchi Jacques , Santurtún Marina
Published: February 2017

Marchal, P., Andersen, B., Caillart, B., Eigaard, Guyader, O., Hovgaard, H., Iriondo, A., Le Fur, F., Sacchi, J., and Santurtún, M. 2007. Impact of technological creep on fishing effort and fishing mortality, for a selection of European fleets–ICES Journal of Marine Science, 64, 192–209. Face-to-face interviews were conducted to identify the main changes in gear and vessel technology that may have improved the fishing efficiency of a number of French, Danish, and Basque fleets over the past few decades. Important changes include the gradual appearance of twin trawls (Danish and French trawlers) and trammel-nets (French gillnetters), and the increased polyvalence of Basque bottom trawlers. The results suggest that fishing effort descriptors that are not traditionally measured (gear type, groundrope type, length of net used per day, headline length, crew size, number of winch or net drums) may have a substantial impact on catch rates. Adjusting fishing effort using such descriptors may generally improve the relationship between fishing effort and fishing mortality.
Biophysical and biochemical control of cell expansion in roots and leaves
Authors: Tomos Deri , Pritchard Jeremy
Published: February 2017

The endogenous regulation of the extension of cells and tissues appears to be dominated by cell wail mechanics. By simultaneously measuring growth rate at near-single cell resolution and single cell turgor pressure we have begun to chart the behaviour of an expanding cell as it passes from the meristem to the mature region of the roots of maize, wheat, barley, tomato, and Pinus pinaster. A key feature is that turgor pressure is unchanged throughout the development of the cell. Two phases can be distinguished within the expanding zone, (i) An acceleration phase in which the cell walls loosen. The cells of this phase can rapidly alter their wall mechanics following water stress and have the most powerful capacity for osmotic adjustment. This phase is associated with a peak in the activity of the potential cell-wall-loosening enzyme XET. (ii) A decelerating phase in which the walls stiffen. This phase can be initiated prematurely by a number of external factors such as NaCI, high osmotic pressure, galactose and, possibly, soil impedance. The corresponding behaviour of examples of leaf (Lolium, wheat and barley) and stem (Sinapis) growth are discussed. Finally the presence of, and roles for, high concentrations of solutes in the walls of expanding cells are discussed. In this context motor cells that are responsible for reversible movement (e.g. those of Phaseolus pulvini) are compared and contrasted with those undergoing irreversible growth. In the pulvini, movement is due to changes in turgor pressure brought about by changes in the apoplast osmotic pressure.
Dental Enamel as an In Vivo Radiation Dosemeter: Separation of the Diagnostic X Ray Dose from the Dose Due to Natural Sources
Authors: Aldrich J.E. , Pass B.
Published: February 2017

The determination of the radiation exposure history of the population has become increasingly important in the study of the effects of low level radiation. Dental enamel is the only living tissue which retains indefinitely its radiation history, and electron spin resonance measurements have shown that the radiation signal can be resolved down to about 0.1 Gy. Measurements on samples from the general population give radiation exposure estimates that are reasonable, and one measurement on a patient who had radiotherapy to the mouth area showed a good correlation with tumour dose. Recent work by this group has centred on the problem of separating the dose due to natural radiation from that due to medical or dental X rays. By detailed analysis of the energy absorption coefficients and mass attenuation coefficients, and a study of the ESR signal over a wide range of energies we have now been able to separate the two components. The possible areas of application of this technique are discussed.
Instrumentation in Thermoluminescence Dosimetry
Authors: Julius (INVITED) H.W.
Published: February 2017

In the performance of a thermoluminescence dosimetry (TLD) system the equipment plays an important role. Crucial parameters of instrumentation in TLD are discussed in some detail. A review is given of equipment available on the market today - with some emphasis on automation - which is partly based on information from industry and others involved in research and development.
Detection of Thermal Neutrons by CR-39 Using a Boron Implanted Converter
Authors: Makovicka L. , Barelaud B. , Decossas J.L. , Vareille J.C.
Published: February 2017

To detect thermal neutrons, we used the (n,a) reaction on 10B. In order to obtain dose equivalent response for thermal neutrons similar to those obtained for fast neutrons with a (CH2)n radiator, we calculated and realised (n,a) converters by implantation of 10B in polyethylene (CH2)n or in iron. These converters were made on the 400 kV H.V.E.E. accelerator of our laboratory. Concentrations of 10B atoms were used between 1014 atoms.cm-2 and 2 x 1015 atoms.cm-2. We compared our theoretical estimates with experimental results from irradiations in C.E.N. Cadarache and A.E.R.E. Harwell, which were obtained using various detectors (CR-39, CAD) behind the converter. Results are given as the number of registered tracks.mSv-1.cm-2. The influence of implantation parameters was also studied. A good agreement exists between calculations and experimental results for both devices; i.e. 10B in (CH2)n and 10B in iron.
The Response of the Alanine Dosemeter to Low Energy Protons and High Energy Heavy Charged Particles
Authors: Olsen K.J. , Hansen J.W.
Published: February 2017

The relative effectiveness, RE, of dose response in the alanine dosemeter has been measured and predicted from track structure theory calculations for 1, 2, 3, 6, and 16 MeV protons as well as 4 MeV.u-116O, 15.4 MeV.u-158Ni, 13.8 MeV.u-1208Pb, and 15 MeV.u-1238U ions. The decay in the dose response that follows heavy ion exposures has been measured and predicted from the theory of track structure for 1, 2, 3, 6, and 16 MeV protons and 4 MeV.u-116O, 15.2 MeV.u-140Ca, 15.4 MeV.u-158Ni, 13.8 MeV.u-1208Pb, and 5.9 MeV.u-1 and 16.5 MeV.u-1238U ions. The decay has also been measured after exposure at high dose rate to 10 MeV electrons at doses up to 4 MGy. The present work shows that the method of using track structure theory for predicting RE and decay rates of the response of the alanine dosemeter is applicable for the lighter ions, Z<30. Heavier ions give higher RE and decay rates than those calculated.
Microdosimetry in Radioimmunotherapy
Authors: Humm J.L. , Chin L.M. , Cobb L. , Begent R.
Published: February 2017

Antibodies are rapidly being developed which target radionuclides to tumour tissue. The MIRD formulation to calculate absorbed dose from internal emitters has limitations in radiation targeted therapy because of the heterogeneity of antibody distribution through the tumour. This heterogeneity results from vascular and tissue penetration barriers as well as variations in antigen concentration. The problems raised in radioimmunotherapy by the dosimetry of these non-uniform source distributions present an interesting challenge to microdosimetry. Calculations of the mean energy deposition with tumour cell nuclei for randomly distributed 131I and 211At are compared with the case of 131I and 211At-labelled antibody uniformly bound to cell surface antigen. The MIRD dosimetric approach does not address the question of energy deposition at the cellular level, and therefore is unable to differentiate the radiation tumour burden from different source distributions at the microscopic level. Considerable increases in the energy deposition to the cell nucleus may arise due to the geometric weighting of the decay site loci to the periphery of the cell nuclei. The magnitude of this geometric enhancement factor is a function of the inter-cellular distances and the range of the radiation, i.e. the tumour histology and the choice of radionuclide. Methods are being investigated to obtain experimental data for microdosimetric calculations directly from patient tumour biopsy material following the administration of radiolabelled antibody. Automated image analysis techniques are being developed to ascertain the location of the sources and cell nuclear targets using autoradiography and histological staining methods respectively. It is the aim of this study to obtain the distribution of energy deposition to individual cell nuclei from small regions of tumour material in order to obtain a more accurate assessment of tumour cell survival.
Progress in Thermoluminescence Dosimetry at the Institute of Nuclear Sciences, Vinca
Authors: Prokic M.
Published: February 2017

Results are presented on: development of a new MgB4O7 thermoluminescence material with the main TL peak at about 270 oC with extremely stable TL characteristics; improvement of TL sensitivity of graphite-mixed MgB4O7:Dy TL detectors for beta dosimetry; preparation of LiF:Mg,Ti TL dosemeters in the form of sintered pellets, by a simplified preparation method; preparation of thermoluminescent lithium borates doped with manganese or copper, in the form of sintered pellets; production of unique sintered CaSO4:Dy TLD pellets developed at the Institute Vinca. The properties of these TL dosemeters, including sensitivity, reusability and storage characteristics, are presented.
Lyoluminescence of Saccharides as a Tool for Large Scale Dosimetry
Authors: Nickel Th. , Pitt E. , Scharmann A. , Suprihadi T.
Published: February 2017

Lyoluminescence, the radiation induced chemiluminescence of solids like saccharides and salts, has been proposed as a cheap dosemeter for high level dosimetry, i.e. for therapy, accident dosimetry and spice irradiation detection. The tissue-equivalence of materials, as well as the omission of pre- and post-reading handling of those low cost dosemeter materials, may be considered advantageous in comparison with other systems. Up till now one of the factors most inhibiting the introduction of lyoluminescence in routine dosimetry is the insufficiently known role of environmental influences during the solution process, leading to large standard deviations in dose readings. Investigations concerning the behaviour of two typical saccharides and the influence of oxygen on the mechanisms of lyoluminescence are reported here.
Characteristics of a New Type of Vinten Dosemeter for Skin-Extremity Monitoring
Authors: Dutt J.C. , Iles W.J. , Bartlett D.T.
Published: February 2017

A type test has been carried out on a new type of thin TL dosemeter manufactured by Vinten Analytical Systems Ltd of UK. The dosemeter has been tested for its suitability for skin/extremity monitoring in terms of the new ICRU quantity, individual dose equivalent, superficial, Hs (0.07). The new extremity TL dosemeter has a thin cover of 3 mg.cm-2 areal density of an aluminised bilaminar plastic in place of the previous thicker black polyethylene of areal density of ~6 mg.cm-2. The dosemeter is found to be suitable for the measurement of beta ray spectra of mean energies down to 70 keV and for all angles of incidence, but the once-only annealing of these dosemeters may limit the long term field use owing to fading, and sensitivity variations.