bluuebunny/crossref_metadata_2025 huggingface dataset:
Validation of radioactive isotope activity measurement in homogeneous waste drum using Monte Carlo codes
Authors: Thanh T. T. , Tran L. B. , Tam H. D. , Quang M. T. , Ton T. V. , Chuong H. D. , Tao C. V.
Published: July 2017

In this work, the angular dependent efficiency recorded by collimated NaI(Tl) detector is determined a quantification of the activity of mono- and multi-energy gamma emitting isotopes positioning in a waste drum. The simulated efficiencies using both MCNP5 and Geant4 are in good agreement with experimental results. Referring to these simulated efficiencies, we recalculated the source activity with the highest deviation of 13%.
Calculation of the fuel temperature coefficient of reactivity considering non-uniform radial temperature distribution in the fuel rod
Authors: Pazirandeh A. , Mobaraki A. Hooshyar
Published: July 2017

The safe operation of a reactor is based on feedback models. In this paper we attempted to discuss the influence of a non-uniform radial temperature distribution on the fuel rod temperature coefficient of reactivity. The paper demonstrates that the neutron properties of a reactor core is based on effective temperature of the fuel to obtain the correct fuel temperature feedback. The value of volume-averaged temperature being used in the calculations of neutron physics with feedbacks would result in underestimating the probable event. In the calculation it is necessary to use the effective temperature of the fuel in order to provide correct accounting of the fuel temperature feedback. Fuel temperature changes in different zones of the core and consequently reactivity coefficient change are an important parameter for analysis of transient conditions. The restricting factor that compensates the inserted reactivity is the temperature reactivity coefficient and effective delayed neutron fraction.
Study of the response reduction of LiF:Mg, Ti dosimeter for high dose dosimetry
Authors: Torkzadeh F. , Faripour H. , Mardashti F. , Manouchehri F.
Published: July 2017

A single crystal and 5 polycrystalline samples of LiF:Mg, Ti and their pellets were prepared and investigated so as to apply thermoluminescence high gamma dose dosimetry. Three zones of single crystal with dopant concentrations of 200 ppm of Mg and 20 ppm of Ti were also used to prepare the single crystal samples. For polycrystalline samples, dopant concentrations of 0.062 mol% Mg and Ti concentrations in the range of 0.016 and 0.046 mol% were used. All the samples were exposed to gamma doses of 1 kGy to 700 kGy and their response changes were determined by a gamma dose test of about 60 mGy. According to the results obtained, the use of response reduction by curve-fitting up to about 300 kGy can be performed reliably for high dose gamma dosimetry.
New version of the reactor dynamics code DYN3D for Sodium cooled Fast Reactor analyses
Authors: Nikitin E. , Fridman E. , Bilodid Y. , Kliem S.
Published: July 2017

The reactor dynamics code DYN3D being developed at the Helmholtz-Zentrum Dresden-Rossendorf is currently under extension for Sodium cooled Fast Reactor analyses. This paper provides an overview on the new version of DYN3D to be used for SFR core calculations. The current article shortly describes the newly implemented thermal mechanical models, which can account for thermal expansion effects of the reactor core. Furthermore, the methodology used in Sodium cooled Fast Reactor analyses to generate homogenized few-group cross sections is summarized. The conducted and planned verification and validation studies are briefly presented. Related publications containing more detailed descriptions are outlined for the completeness of this overview.
Simulation of water hammer phenomena using the system code ATHLET
Authors: Bratfisch C. , Koch M. K.
Published: July 2017

Water Hammer Phenomena can endanger the integrity of structures leading to a possible failure of pipes in nuclear power plants as well as in many industrial applications. These phenomena can arise in nuclear power plants in the course of transients and accidents induced by the start-up of auxiliary feed water systems or emergency core cooling systems in combination with rapid acting valves and pumps. To contribute to further development and validation of the code ATHLET (Analysis of Thermalhydraulics of Leaks and Transients), an experiment performed in the test facility Pilot Plant Pipework (PPP) at Fraunhofer UMSICHT is simulated using the code version ATHLET 3.0A.
Depressive Symptoms and Tau Accumulation in the Inferior Temporal Lobe and Entorhinal Cortex in Cognitively Normal Older Adults: A Pilot Study
Authors: Gatchel Jennifer R. , Donovan Nancy J. , Locascio Joseph J. , Schultz Aaron P. , Becker J. Alex , Chhatwal Jasmeer , Papp Kathryn V. , Amariglio Rebecca E. , Rentz Dorene M. , Blacker Deborah , Sperling Reisa A. , Johnson Keith A. , Marshall Gad A.
Published: July 2017

Background:

Depressive symptoms are common in older adults and associated with increased morbidity and cognitive decline. These symptoms occur during preclinical and prodromal stages of Alzheimer’s disease (AD), but their relationship to tau, one of the main AD proteinopathies, is poorly understood.

Objective:

The objective of this study was to investigate the cross-sectional association between depressive symptoms and cerebral tau [18F T807 (also known as 18F-AV-1451) tau positron emission tomography (PET) imaging] in cognitively normal (CN) older adults.

Methods:

We measured depressive symptoms using the Geriatric Depression Scale (GDS), and in vivo cerebral tau using T807 PET in 111 CN older adults. We employed general linear regression models to evaluate the relationship of GDS score regressed on entorhinal cortex (EC) or inferior temporal (IT) tau in separate backward elimination models. Other predictors included age, sex, and in secondary analyses, amyloid (Pittsburgh Compound B PET).

Results:

Higher GDS was significantly associated with greater IT tau (partial r = 0.188, p = 0.050) and marginally associated with greater EC tau (partial r = 0.183, p = 0.055). In additional analyses including both linear and quadratic age terms, we found a significant U-shaped relation of GDS to age ( p = 0.001).

Conclusions:

Results suggest that IT and EC tau are modestly associated with depressive symptoms in CN older adults. Findings suggest a link between depressive symptoms and tau-mediated neurodegeneration in a region vulnerable in AD. Future longitudinal studies examining the association of more severe depressive symptoms and cerebral tau accumulation are needed to substantiate this finding and to guide prevention and treatment in AD.
An Intracellular Amyloid-β/AβPP Epitope Correlates with Neurodegeneration in those Neuronal Populations Early Involved in Alzheimer’s Disease
Authors: Esquerda-Canals Gisela , Martí-Clúa Joaquim , Roda Alejandro R. , Villegas Sandra
Published: July 2017

The main histopathological hallmarks of Alzheimer’s disease (AD) are the extracellular deposition of neuritic amyloid plaques, composed of amyloid-β (Aβ) peptide, and the intracellular accumulation of neurofibrillary tangles, composed of hyperphosphorylated tau. Both traits are emulated in the 3xTg-AD mouse model. Because the relevance of this model in the bibliography and the main role of Aβ in neuronal impairment, here we have detailed the brain Aβ/AβPP distribution to subsequently quantify cellular density and intracellular burden for specific neuronal populations in the early stages of the disease. 6E10 immunoreactivity was evident in the deep layers of the cerebral cortex, in the pyramidal cell layer of the hippocampus, in the basolateral amygdala nucleus, and in the deep cerebellar nuclei macroneurons; whereas the specific neuronal populations with decreased cellular density were the large pyramidal neurons from the layers V-VI in the cerebral cortex, the pyramidal neurons from the CA2-3 region in the hippocampus, and the large neurons from the basolateral nucleus in the amygdala, apart from the already reported deep cerebellar nuclei. Interestingly, we found a strong correlation between intracellular Aβ/AβPP burden and cellular density in all these populations. In addition, behavioral testing showed the functional consequences of such a neuronal depletion. Concretely, anxious-like behavior is manifested in the corner and open-field tests, as well as cognitive functions shown to be impaired in the novel object recognition test and Morris water maze paradigm. To our knowledge, this is the first deep characterization of the specific neuronal populations affected in the 3xTg-AD mouse model.
Antibodies to Signaling Molecules and Receptors in Alzheimer’s Disease are Associated with Psychomotor Slowing, Depression, and Poor Visuospatial Function
Authors: Giil Lasse M. , Vedeler Christian A. , Kristoffersen Einar K. , Nordrehaug Jan Erik , Heidecke Harald , Dechend Ralf , Schulze-Forster Kai , Muller Dominik N. , von Goetze Victoria S. , Cabral-Marques Otavio , Riemekasten Gabriela , Vogelsang Petra , Nygaard Staale , Lund Anders , Aarsland Dag
Published: July 2017

Background:

Alzheimer’s disease (AD) is associated with several antibodies as well as signaling molecules and receptors. These may be detrimental in the presence of a disrupted blood-brain barrier (BBB).

Objective:

To investigate whether the levels of antibodies toward 33 signaling molecules involved in neurotransmitter, vascular, and immune functions were associated with AD and, within the AD group; cognitive function and mood.

Methods:

Antibodies in sera from patients with mild AD [( n = 91) defined as a Mini-Mental State Examination ≥ 20 or a Clinical Dementia Rating Scale≤1] and healthy controls ( n = 102) were measured with enzyme-linked immunosorbent assays. Levels in AD and controls were compared by Mann-Whitney test. In the AD group, associations between antibodies and psychometric test scores were analyzed by robust regression. The false discovery threshold was set to 0.05.

Results:

Antibodies to serotonin receptors [5-HT2AR (effect size ( r) = 0.21, p = 0.004), 5-HT2CR ( r = 0.25 , p = 0.0005) and 5-HT7R ( r = 0.21, p = 0.003)], vascular endothelial growth factor receptor 1 [VEGFR1 ( r = 0.29, p < 0.001)] and immune-receptors (Stabilin-1 ( r = 0.23, p = 0.001) and C5aR1 ( r = 0.21, p = 0.004) were higher in AD. Psychomotor speed was associated with D1R-abs (β 0.49, p < 0.001), depression with ETAR-abs (β 0.31, p < 0.001), and visuospatial function with 5-HT1AR-abs (β 0.27, p = 0.004) despite similar antibody levels compared to controls.

Conclusions:

Antibody levels to VEGFR1, serotonergic receptors, and receptors in the immune system were increased in AD. Antibodies at similar levels as in controls were associated cognitive dysfunction and depression in AD.
Autophagy-ERK1/2-Involved Disinhibition of Hippocampal Neurons Contributes to the Pre-Synaptic Toxicity Induced by Aβ42 Exposure
Authors: Yin Yanling , Zhao Yuanyuan , Han Song , Zhang Nan , Chen Hanyu , Wang Xiaomin
Published: July 2017

Alzheimer’s disease (AD) is a progressive neurodegenerative disease and the most frequent cause of progressive cognitive decline in the elderly population. To date, there is still no effective treatment for AD, requiring more underlying mechanisms. In the present study, we investigated the effects of Aβ42 on the inhibitory synaptic transmission in the cultured hippocampal neurons, and explored the possible mechanism. The frequency, but not amplitude, of miniature inhibitory post-synaptic currents was significantly suppressed by Aβ42, indicating that Aβ42 played its role in inhibitory transmitter release at the pre-synaptic sites. Aβ42 had no effect on miniature excitatory post-synaptic currents, suggesting GABAergic synapses are more susceptible to Aβ42 exposure. However, the number of GABAergic neurons or synapses was not influenced, suggesting the corresponding stage may be a preclinical one. The effect of Aβ42 can be mimicked by PD98059 (an inhibitor of ERK1/2) and blocked by curcumin (an activator of MEK), which reveals Aβ-involved influence is via the decreased phosphorylation of MAPK-ERK1/2. In addition, synaptophysin is confirmed to be a downstream protein of MAPK-ERK1/2 at the pre-synaptic site. At the same time, suppressed autophagy was observed after Aβ42 exposure, and the activation of autophagy increased pERK1/2 level and salvaged the disinhibition of hippocampal neurons. These data suggest that diminished GABAergic tone likely starts from the preclinical stage of AD, so some GABAergic stress test may be effective for identifying cognitively normal elder adults. Strategies against the dysfunction of autophagy should be adopted in the early stage of AD because of its initial effects.
Prevalence and pattern of gastrointestinal symptoms in patients with diabetes mellitus
Authors: Lona Hafiza , Selim Shahjada
Published: July 2017

Background and objectives: Gastrointestinal (GI) disorders are contributor of increased morbidity and poor quality of life in individuals with diabetes mellitus (DM). Racial, nutritional and life style may influence GI disorders to a large extent. Thus, the burden of GI disorders and its determinants warrant investigation in individual population. Therefore, the present study was undertaken to explore the types of GI symptoms in Bangladeshi population with DM for more than 10 years of duration.Methodology: This observational study was conducted on patients with DM for more than 10 years of duration at the outpatient department of BIRDEM general hospital from July 2009 to June 2010. A total of 301 DM patients responded to self-reporting questionnaire (Bengali adaptation of Rome III diagnostic questionnaire). Then 91 participants were further studied for glycemic status, liver function, kidney function and basic defects of diabetes through homeostasis model assessment.Results: The median age of 301 study population was 55 years (range 25 to 84 years) and the male female ratio was 1: 0.74. Out of 301 DM cases, 273 (90.7%) had GI symptoms. Significantly (p<0.05) higher number of males (93.6%) had GI symptoms compared to females (86.7%). Among the clinical conditions, unspecified functional bowel disorder (UFBD) was present in 88.3% cases, followed by cyclic vomiting syndrome (38.1%) and functional fecal incontinence (20.9%). Single GI symptom was present in 123 (45.1%) cases while 32.6%, 12.5% and 9.9% had two, three and more than three GI symptoms respectively. No significant difference was found in any biochemical parameter between cases with and without GI symptoms. Multiple logistic regression analysis revealed sex and residence as poor predictors of UFBD while other variables did not show any significant relation/risk to UFBD.Conclusion: A large proportion of patients with long duration of DM had GI symptoms. A comprehensive management of diabetes requires attention to GI disorders.IMC J Med Sci 2017; 11(2): 56-60
‘Crooked roads without improvement’: Rhyming and Unrhyming in Blake
Authors: Kellett Lucy
Published: July 2017

This essay posits rhyme as an important locus of invigorating ‘Contraries’ in Blake's spiritual ideology and poetic practice. It explores tensions in Blake's conception of rhyme as unthinking abandon and over-reasoning rigidity, a trivialising indulgence yet rife with Urizenic implications. Moving through the Poetical Sketches and Songs to the climactic epic Jerusalem, we see how Blake seeks greater formal freedom in more capacious – or ‘crooked’ – poetic lines, aiming to embody the unrehearsed voice of a ‘true Orator’ and avoid passive ‘Sing Song’ reading. But Blake also frequently exploits the fixity of formal rhyme schemes to dramatically enact the oppressiveness of ‘enclos'd’ mindsets, so that the ‘bounding lines’ of his form often pivot between expressing and imposing ideas of order that bespeak both technical precision and limitation. The essay goes on to consider Blake's use of repetition in particular as one means of reconciling the paradoxes flung up by the presence and absence of rhyme throughout his canon.
‘Chosen Comrades’: Yeats's Romantic Rhymes
Authors: Callaghan Madeleine
Published: July 2017

Yeats's acute sense of the poet's labour, a labour that makes rhyme one of those ‘befitting emblems of adversity’ (‘My House’, Meditations in Time of Civil War, 30) energises his poetry. Rather than constricting poetry, rhyme can engender, if paradoxically, a kind of freedom for the poet; Yeats's choice of form reveals his Romantic influences while demonstrating his independence. Encompassing examples from Blake, Byron, Keats, and Shelley, this essay shows how Yeats learns from his chosen influences even as his mastery over their forms sponsors his ‘ghostly solitude’ (‘Nineteen Hundred and Nineteen’, 40). From his experimentation with trimeter to ottava rima and terza rima, Yeats's formal dexterity places rhyme centre stage as he emerges as a resolutely individual poet.
Discrimination of Aortic and Pulmonary Components from the Second Heart Sound Using Respiratory Modulation and Measurement of Respiratory Split
Authors: Tang Hong , Chen Huaming , Li Ting
Published: July 2017

The second heart sound consists of aortic and pulmonary components. Analysis on the changes of the second heart sound waveform in respiration shows that the aortic component has little variation and the delay of the pulmonary component is modulated by respiration. This paper proposes a novel model to discriminate the aortic and pulmonary components using respiratory modulation. It is found that the aortic component could be simply extracted by averaging the second heart sounds over respiratory phase, and the pulmonary component could be extracted by subtraction. Hence, the split is measured by the timing difference of the two components. To validate the measurement, the method is applied to simulated second heart sounds with known varying splits. The simulation results show that the aortic and pulmonary components can be successfully extracted and the measured splits are close to the predefined splits. The method is further evaluated by data collected from 12 healthy subjects. Experimental results show that the respiratory split can be accurately measured. The minimum split generally occurs at the end of expiration and the split value is about 20 ms. Meanwhile, the maximum split is about 50 ms at the end of inspiration. Both the trend of split varying with respect to respiratory phase and the numerical range of split varying are comparable to the results disclosed by previous physiologists. The proposed method is compared to the two previous well known methods. The most attractive advantage of the proposed method is much less complexity. This method has potential applications in monitoring heart hemodynamic response to respiration.
Detection of Lipid and Amphiphilic Biomarkers for Disease Diagnostics
Authors: Kubicek-Sutherland Jessica , Vu Dung , Mendez Heather , Jakhar Shailja , Mukundan Harshini
Published: July 2017

Rapid diagnosis is crucial to effectively treating any disease. Biological markers, or biomarkers, have been widely used to diagnose a variety of infectious and non-infectious diseases. The detection of biomarkers in patient samples can also provide valuable information regarding progression and prognosis. Interestingly, many such biomarkers are composed of lipids, and are amphiphilic in biochemistry, which leads them to be often sequestered by host carriers. Such sequestration enhances the difficulty of developing sensitive and accurate sensors for these targets. Many of the physiologically relevant molecules involved in pathogenesis and disease are indeed amphiphilic. This chemical property is likely essential for their biological function, but also makes them challenging to detect and quantify in vitro. In order to understand pathogenesis and disease progression while developing effective diagnostics, it is important to account for the biochemistry of lipid and amphiphilic biomarkers when creating novel techniques for the quantitative measurement of these targets. Here, we review techniques and methods used to detect lipid and amphiphilic biomarkers associated with disease, as well as their feasibility for use as diagnostic targets, highlighting the significance of their biochemical properties in the design and execution of laboratory and diagnostic strategies. The biochemistry of biological molecules is clearly relevant to their physiological function, and calling out the need for consideration of this feature in their study, and use as vaccine, diagnostic and therapeutic targets is the overarching motivation for this review.
Ultrasonographic Diagnosis of Thoracic Outlet Syndrome Secondary to Brachial Plexus Piercing Variation
Authors: Leonhard Vanessa , Caldwell Gregory , Goh Mei , Reeder Sean , Smith Heather
Published: July 2017

Structural variations of the thoracic outlet create a unique risk for neurogenic thoracic outlet syndrome (nTOS) that is difficult to diagnose clinically. Common anatomical variations in brachial plexus (BP) branching were recently discovered in which portions of the proximal plexus pierce the anterior scalene. This results in possible impingement of BP nerves within the muscle belly and, therefore, predisposition for nTOS. We hypothesized that some cases of disputed nTOS result from these BP branching variants. We tested the association between BP piercing and nTOS symptoms, and evaluated the capability of ultrasonographic identification of patients with clinically relevant variations. Eighty-two cadaveric necks were first dissected to assess BP variation frequency. In 62.1%, C5, superior trunk, or superior + middle trunks pierced the anterior scalene. Subsequently, 22 student subjects underwent screening with detailed questionnaires, provocative tests, and BP ultrasonography. Twenty-one percent demonstrated atypical BP branching anatomy on ultrasound; of these, 50% reported symptoms consistent with nTOS, significantly higher than subjects with classic BP anatomy (14%). This group, categorized as a typical TOS, would be missed by provocative testing alone. The addition of ultrasonography to nTOS diagnosis, especially for patients with BP branching variation, would allow clinicians to visualize and identify atypical patient anatomy.
Big-Data-Based Thermal Runaway Prognosis of Battery Systems for Electric Vehicles
Authors: Hong Jichao , Wang Zhenpo , Liu Peng
Published: July 2017

A thermal runaway prognosis scheme for battery systems in electric vehicles is proposed based on the big data platform and entropy method. It realizes the diagnosis and prognosis of thermal runaway simultaneously, which is caused by the temperature fault through monitoring battery temperature during vehicular operations. A vast quantity of real-time voltage monitoring data is derived from the National Service and Management Center for Electric Vehicles (NSMC-EV) in Beijing. Furthermore, a thermal security management strategy for thermal runaway is presented under the Z-score approach. The abnormity coefficient is introduced to present real-time precautions of temperature abnormity. The results illustrated that the proposed method can accurately forecast both the time and location of the temperature fault within battery packs. The presented method is flexible in all disorder systems and possesses widespread application potential in not only electric vehicles, but also other areas with complex abnormal fluctuating environments.
Grid Synchronization of a Seven-Phase Wind Electric Generator Using d-q PLL
Authors: Chandramohan Kalaivani , Padmanaban Sanjeevikumar , Kalyanasundaram Rajambal , Bhaskar Mahajan Sagar , Mihet-Popa Lucian
Published: July 2017

The evolving multiphase induction generators (MPIGs) with more than three phases are receiving prominence in high power generation systems. This paper aims at the development of a comprehensive model of the wind turbine driven seven-phase induction generator (7PIG) along with the necessary power electronic converters and the controller for grid interface. The dynamic model of the system is developed in MATLAB/Simulink (R2015b, The MathWorks, Inc., Natick, MA, USA). A synchronous reference frame phase-locked loop (SRFPLL) system is incorporated for grid synchronization. The modeling aspects are detailed and the system response is observed for various wind velocities. The effectiveness of the seven phase induction generator is demonstrated with the fault tolerant capability and high output power with reduced phase current when compared to the conventional 3-phase wind generation scheme. The response of the PLL is analysed and the results are presented.
Design of Ecological CO2 Enrichment System for Greenhouse Production using TBAB + CO2 Semi-Clathrate Hydrate
Authors: Takeya Satoshi , Muromachi Sanehiro , Maekawa Tatsuo , Yamamoto Yoshitaka , Mimachi Hiroko , Kinoshita Takahiro , Murayama Tetsuro , Umeda Hiroki , Ahn Dong-Hyuk , Iwasaki Yasunaga , Hashimoto Hidenori , Yamaguchi Tsutomu , Okaya Katsunori , Matsuo Seiji
Published: July 2017

This paper proposes an innovative CO2 enrichment system for crop production under a controlled greenhouse environment by means of tetra-n-butylammonium bromide (TBAB) + CO2 semi-clathrate hydrate (SC). In this system, CO2 is captured directly from exhaust gas from a combustion heater at night, which can be used for stimulating photosynthesis of crops in greenhouses during daytime. Although the gas capacity of TBAB + CO2 SC is less than that of CO2 gas hydrate, it is shown that TBAB + CO2 SC can store CO2 for CO2 enrichment in crop production even under moderate pressure conditions (<1.0 MPa) at 283 K.
Mixing It Up: The Role of Hybridization in Forest Management and Conservation under Climate Change
Authors: Janes Jasmine , Hamilton Jill
Published: July 2017

Forest tree hybrid zones provide a wealth of novel genetic variation that can be harnessed to safeguard populations in changing climates. In the past 30 years, natural and artificial forest hybrid zones have facilitated significant contributions to selective breeding programs, conservation, and our understanding of the evolutionary processes and mechanisms that influence the maintenance of species and community interactions. This review highlights advances in these areas using forest hybrid zones. Taking examples from well-known genera, including eucalypt, poplar, oak and spruce, this review details the important role hybrid zones play in managing conservation of genetic variation, the environmental and non-environmental factors that influence barriers to reproduction, and the impact that genetic ancestry may have on community biodiversity. Given increasing concern surrounding species adaptability under rapidly changing conditions, we describe how the study of forest hybrid zones, using quantitative and genomic approaches, can facilitate conservation of genetic diversity and long-term species management.
Health Risks Associated with Exposure to Filamentous Fungi
Authors: Egbuta Mary , Mwanza Mulunda , Babalola Olubukola
Published: July 2017

Filamentous fungi occur widely in the environment, contaminating soil, air, food and other substrates. Due to their wide distribution, they have medical and economic implications. Regardless of their use as a source of antibiotics, vitamins and raw materials for various industrially important chemicals, most fungi and filamentous fungi produce metabolites associated with a range of health risks, both in humans and in animals. The association of filamentous fungi and their metabolites to different negative health conditions in humans and animals, has contributed to the importance of investigating different health risks induced by this family of heterotrophs. This review aims to discuss health risks associated with commonly occurring filamentous fungal species which belong to genera Aspergillus, Penicillium and Fusarium, as well as evaluating their pathogenicity and mycotoxic properties.
FRET-Mediated Long-Range Wavelength Transformation by Photoconvertible Fluorescent Proteins as an Efficient Mechanism to Generate Orange-Red Light in Symbiotic Deep Water Corals
Authors: Bollati Elena , Plimmer Daniel , D’Angelo Cecilia , Wiedenmann Jörg
Published: July 2017

Photoconvertible fluorescent proteins (pcRFPs) are a group of fluorophores that undergo an irreversible green-to-red shift in emission colour upon irradiation with near-ultraviolet (near-UV) light. Despite their wide application in biotechnology, the high-level expression of pcRFPs in mesophotic and depth-generalist coral species currently lacks a biological explanation. Additionally, reduced penetration of near-UV wavelengths in water poses the question whether light-driven photoconversion is relevant in the mesophotic zone, or whether a different mechanism is involved in the post-translational pigment modification in vivo. Here, we show in a long-term mesocosm experiment that photoconversion in vivo is entirely dependent on near-UV wavelengths. However, a near-UV intensity equivalent to the mesophotic underwater light field at 80 m depth is sufficient to drive the process in vitro, suggesting that photoconversion can occur near the lower distribution limits of these corals. Furthermore, live coral colonies showed evidence of efficient Förster Resonance Energy Transfer (FRET). Our simulated mesophotic light field maintained the pcRFP pool in a partially photoconverted state in vivo, maximising intra-tetrameric FRET and creating a long-range wavelength conversion system with higher quantum yield than other native RFPs. We hypothesise that efficient conversion of blue wavelengths, abundant at depth, into orange-red light could constitute an adaptation of corals to life in light-limited environments.
Effect of Oxidative Stress on Cardiovascular System in Response to Gravity
Authors: Takahashi Ken , Okumura Hiroki , Guo Rui , Naruse Keiji
Published: July 2017

Long-term habitation in space leads to physiological alterations such as bone loss, muscle atrophy, and cardiovascular deconditioning. Two predominant factors—namely space radiation and microgravity—have a crucial impact on oxidative stress in living organisms. Oxidative stress is also involved in the aging process, and plays important roles in the development of cardiovascular diseases including hypertension, left ventricular hypertrophy, and myocardial infarction. Here, we discuss the effects of space radiation, microgravity, and a combination of these two factors on oxidative stress. Future research may facilitate safer living in space by reducing the adverse effects of oxidative stress.
Inter-Strain Differences in LINE-1 DNA Methylation in the Mouse Hematopoietic System in Response to Exposure to Ionizing Radiation
Authors: Miousse Isabelle , Chang Jianhui , Shao Lijian , Pathak Rupak , Nzabarushimana Étienne , Kutanzi Kristy , Landes Reid , Tackett Alan , Hauer-Jensen Martin , Zhou Daohong , Koturbash Igor
Published: July 2017

Long Interspersed Nuclear Element 1 (LINE-1) retrotransposons are the major repetitive elements in mammalian genomes. LINE-1s are well-accepted as driving forces of evolution and critical regulators of the expression of genetic information. Alterations in LINE-1 DNA methylation may lead to its aberrant activity and are reported in virtually all human cancers and in experimental carcinogenesis. In this study, we investigated the endogenous DNA methylation status of the 5′ untranslated region (UTR) of LINE-1 elements in the bone marrow hematopoietic stem cells (HSCs), hematopoietic progenitor cells (HPCs), and mononuclear cells (MNCs) in radioresistant C57BL/6J and radiosensitive CBA/J mice and in response to ionizing radiation (IR). We demonstrated that basal levels of DNA methylation within the 5′-UTRs of LINE-1 elements did not differ significantly between the two mouse strains and were negatively correlated with the evolutionary age of LINE-1 elements. Meanwhile, the expression of LINE-1 elements was higher in CBA/J mice. At two months after irradiation to 0.1 or 1 Gy of 137Cs (dose rate 1.21 Gy/min), significant decreases in LINE-1 DNA methylation in HSCs were observed in prone to radiation-induced carcinogenesis CBA/J, but not C57BL/6J mice. At the same time, no residual DNA damage, increased ROS, or changes in the cell cycle were detected in HSCs of CBA/J mice. These results suggest that epigenetic alterations may potentially serve as driving forces of radiation-induced carcinogenesis; however, future studies are needed to demonstrate the direct link between the LINE-1 DNA hypomethylation and radiation carcinogenesis.
Polymorphisms within Genes Involved in Regulation of the NF-κB Pathway in Patients with Rheumatoid Arthritis
Authors: Gębura Katarzyna , Świerkot Jerzy , Wysoczańska Barbara , Korman Lucyna , Nowak Beata , Wiland Piotr , Bogunia-Kubik Katarzyna
Published: July 2017

Genes involved in regulation of the nuclear factor-κB (NF-κB)—pathway are suggested to play a role in pathogenesis of rheumatoid arthritis (RA). In the present study, genetic polymorphisms of TLR2, TLR4, TLR9 and NF-κB1 genes were investigated to assess their associations with RA susceptibility, progression and response to anti-TNF-α therapy. A group of 110 RA patients and 126 healthy individuals were genotyped for TLR2 (rs111200466), TLR4 (rs4986790, rs4986791), TLR9 (rs5743836, rs187084) and NF-κB1 (rs28362491) alleles. The presence of the TLR9 −1486 T variant (p < 0.0001) and its homozygosity (p < 0.0001) were found to be associated with disease susceptibility. The TLR9 −1237 C allele was associated with predisposition to RA in females only (p = 0.005). Moreover, the TLR4 rs4986791 G (rs4986790 T) alleles were more frequently detected among patients with the stage IV disease (p = 0.045), and were associated with more effective response to anti-TNF-α therapy (p = 0.012). More efficient response to anti-TNF-α treatment was also observed in patients with del within the NF-κB1 gene (p = 0.047), while for the TLR9 −1486 T homozygotes, the treatment was ineffective (p = 0.018). TLR polymorphisms affect disease susceptibility and response to therapy with TNF-α inhibitors in RA patients of Caucasian origin.
Multi-Approach Analysis for the Identification of Proteases within Birch Pollen
Authors: McKenna Olivia E. , Posselt Gernot , Briza Peter , Lackner Peter , Schmitt Armin O. , Gadermaier Gabriele , Wessler Silja , Ferreira Fatima
Published: July 2017

Birch pollen allergy is highly prevalent, with up to 100 million reported cases worldwide. Proteases in such allergen sources have been suggested to contribute to primary sensitisation and exacerbation of allergic disorders. Until now the protease content of Betula verrucosa, a birch species endemic to the northern hemisphere has not been studied in detail. Hence, we aim to identify and characterise pollen and bacteria-derived proteases found within birch pollen. The pollen transcriptome was constructed via de novo transcriptome sequencing and analysis of the proteome was achieved via mass spectrometry; a cross-comparison of the two databases was then performed. A total of 42 individual proteases were identified at the proteomic level. Further clustering of proteases into their distinct catalytic classes revealed serine, cysteine, aspartic, threonine, and metallo-proteases. Further to this, protease activity of the pollen was quantified using a fluorescently-labelled casein substrate protease assay, as 0.61 ng/mg of pollen. A large number of bacterial strains were isolated from freshly collected birch pollen and zymographic gels with gelatinase and casein, enabled visualisation of proteolytic activity of the pollen and the collected bacterial strains. We report the successful discovery of pollen and bacteria-derived proteases of Betula verrucosa.
An Emerging Role for Tubulin Isotypes in Modulating Cancer Biology and Chemotherapy Resistance
Authors: Parker Amelia L. , Teo Wee Siang , McCarroll Joshua A. , Kavallaris Maria
Published: July 2017

Tubulin proteins, as components of the microtubule cytoskeleton perform critical cellular functions throughout all phases of the cell cycle. Altered tubulin isotype composition of microtubules is emerging as a feature of aggressive and treatment refractory cancers. Emerging evidence highlighting a role for tubulin isotypes in differentially influencing microtubule behaviour and broader functional networks within cells is illuminating a complex role for tubulin isotypes regulating cancer biology and chemotherapy resistance. This review focuses on the role of different tubulin isotypes in microtubule dynamics as well as in oncogenic changes that provide a survival or proliferative advantage to cancer cells within the tumour microenvironment and during metastatic processes. Consideration of the role of tubulin isotypes beyond their structural function will be essential to improving the current clinical use of tubulin-targeted chemotherapy agents and informing the development of more effective cancer therapies.
Pro and Contra: Provocation Tests in Drug Hypersensitivity
Authors: Soyer Ozge , Sahiner Umit Murat , Sekerel Bulent Enis
Published: July 2017

Drug provocation test (DPT) is the controlled administration of a drug to diagnose immune- or non-immune-mediated drug hypersensitivity and the last step for accurate recognition of drug hypersensitivity reactions when the previous diagnostic evaluations are negative or unavailable. A DPT is performed only if other conventional tests fail to yield conclusive results. In each clinical presentation, “to provoke or not to provoke” a patient should be decided after careful assessment of the risk–benefit ratio. Well-defined benefits of DPT include confirmative exclusion of diagnoses of drug hypersensitivity and provision of safe alternatives. However, disadvantages such as safety, difficulty in interpretations of results, lack of objective biomarkers, risks of resensitization, efficiency in daily practice, and lack of standardized protocols, are poorly debated. This review summarizes the current published research concerning DPT, with particular emphasis on the advantages and disadvantages of DPT in an evidence-based manner.
Cytotoxic Effects of Sarcophyton sp. Soft Corals—Is There a Correlation to Their NMR Fingerprints?
Authors: Farag Mohamed , Fekry Mostafa , Al-Hammady Montasser , Khalil Mohamed , El-Seedi Hesham , Meyer Achim , Porzel Andrea , Westphal Hildegard , Wessjohann Ludger
Published: July 2017

Sarcophyton sp. soft corals are rich in cembranoid diterpenes, which represent the main chemical defense of corals against their natural predators in addition to their myriad biological effects in humans. Quantitative NMR (qNMR) was applied for assessing the diterpene variation in 16 soft coral specimens in the context of their genotype, origin, and growing habitat. qNMR revealed high diterpene levels in Sarcophyton sp. compared to Sinularia and Lobophyton, with (ent)sarcophines as major components (17–100 µg/mg) of the coral tissues. Multivariate data analysis was employed to classify samples based on the quantified level of diterpenes, and compared to the untargeted NMR approach. Results revealed that qNMR provided a stronger classification model of Sarcophyton sp. than untargeted NMR fingerprinting. Additionally, cytotoxicity of soft coral crude extracts was assessed against androgen-dependent prostate cancer cell lines (PC3) and androgen-independent colon cancer cell lines (HT-29), with IC50 values ranging from 10–60 µg/mL. No obvious correlation between the extracts’ IC50 values and their diterpene levels was found using either Spearman or Pearson correlations. This suggests that this type of bioactivity may not be easily predicted by NMR metabolomics in soft corals, or is not strongly correlated to measured diterpene levels.
Simulation Analysis of Improving Microfluidic Heterogeneous Immunoassay Using Induced Charge Electroosmosis on a Floating Gate
Authors: Hu Qingming , Ren Yukun , Liu Weiyu , Tao Ye , Jiang Hongyuan
Published: July 2017

On-chip immuno-sensors are a hot topic in the microfluidic community, which is usually limited by slow diffusion-dominated transport of analytes in confined microchannels. Specifically, the antigen-antibody binding reaction at a functionalized area cannot be provided with enough antigen source near the reaction surface, since a small diffusion flux cannot match with the quick rate of surface reaction, which influences the response time and sensitivity of on-chip heterogeneous immunoassay. In this work, we propose a method to enhance the transportation of biomolecules to the surface of an antibody-immobilized electrode with induce charge electroosmotic (ICEO) convection in a low concentration suspension, so as to improve the binding efficiency of microfluidic heterogeneous immunoassays. The circular stirring fluid motion of ICEO on the surface of a floating gate electrode at the channel bottom accelerates the transport of freely suspended antigen towards the wall-immobilized antibodies. We investigate the dependence of binding efficiency on voltage magnitude and field frequency of the applied alternate current (AC) electrical field. The binding rate yields a factor of 5.4 higher binding for an applied voltage of 4 V at 10 Hz when the Damkohler number is 1000. The proposed microfluidic immuno-sensor technology of a simple electrode structure using ICEO convective fluid flow around floating conductors could offer exciting opportunities for diffusion-limited on-chip bio-microfluidic sensors.
Synthesis and Evaluation of New Oxadiazole, Thiadiazole, and Triazole Derivatives as Potential Anticancer Agents Targeting MMP-9
Authors: Özdemir Ahmet , Sever Belgin , Altıntop Mehlika , Temel Halide , Atlı Özlem , Baysal Merve , Demirci Fatih
Published: July 2017

Matrix metalloproteinases (MMPs) are important proteases involved in tumor progression including angiogenesis, tissue invasion, and migration. Therefore, MMPs have been reported as potential diagnostic and prognostic biomarkers in many types of cancer. New oxadiazole, thiadiazole, and triazole derivatives were synthesized and evaluated for their anticancer effects on A549 human lung adenocarcinoma and C6 rat glioma cell lines. In order to examine the relationship between their anticancer activity and MMP-9, the compounds were evaluated for their inhibitory effects on MMPs. N-(1,3-Benzodioxol-5-ylmethyl)-2-{[5,[5-(((5,6,7,8-tetrahydronaphthalen-2-yl)oxy)methyl)-1,3,4-oxadiazol-2-yl]thio}acetamide (8) and N-(1,3-benzodioxol-5-ylmethyl)-2-[(5-phenyl-1,3,4-oxadiazol-2-yl)thio]acetamide (9) revealed promising cytotoxic effects on A549 and C6 cell lines similar to cisplatin without causing any toxicity towards NIH/3T3 mouse embryonic fibroblast cell line. Compounds 8 and 9 were also the most effective MMP-9 inhibitors in this series. Moreover, docking studies pointed out that compounds 8 and 9 had good affinity to the active site of the MMP-9 enzyme. The molecular docking and in vitro studies suggest that the MMP-9 inhibitory effects of compounds 8 and 9 may play an important role in lung adenocarcinoma and glioma treatment.
Chiral Nanotubes
Authors: Nitti Andrea , Pacini Aurora , Pasini Dario
Published: July 2017

Organic nanotubes, as assembled nanospaces, in which to carry out host–guest chemistry, reversible binding of smaller species for transport, sensing, storage or chemical transformation purposes, are currently attracting substantial interest, both as biological ion channel mimics, or for addressing tailored material properties. Nature’s materials and machinery are universally asymmetric, and, for chemical entities, controlled asymmetry comes from chirality. Together with carbon nanotubes, conformationally stable molecular building blocks and macrocycles have been used for the realization of organic nanotubes, by means of their assembly in the third dimension. In both cases, chiral properties have started to be fully exploited to date. In this paper, we review recent exciting developments in the synthesis and assembly of chiral nanotubes, and of their functional properties. This review will include examples of either molecule-based or macrocycle-based systems, and will try and rationalize the supramolecular interactions at play for the three-dimensional (3D) assembly of the nanoscale architectures.
Effect of Precursor on Antifouling Efficacy of Vertically-Oriented Graphene Nanosheets
Authors: Prasad Karthika , Bandara Chaturanga , Kumar Shailesh , Singh Gurinder , Brockhoff Bastian , Bazaka Kateryna , Ostrikov Kostya
Published: July 2017

Antifouling efficacy of graphene nanowalls, i.e., substrate-bound vertically-oriented graphene nanosheets, has been demonstrated against biofilm-forming Gram-positive and Gram-negative bacteria. Where graphene nanowalls are typically prepared using costly high-temperature synthesis from high-purity carbon precursors, large-scale applications demand efficient, low-cost processes. The advancement of plasma enabled synthesis techniques in the production of nanomaterials has opened a novel and effective method for converting low-cost natural waste resources to produce nanomaterials with a wide range of applications. Through this work, we report the rapid reforming of sugarcane bagasse, a low-value by-product from sugarcane industry, into high-quality vertically-oriented graphene nanosheets at a relatively low temperature of 400 °C. Electron microscopy showed that graphene nanowalls fabricated from methane were significantly more effective at preventing surface attachment of Gram-negative rod-shaped Escherichia coli compared to bagasse-derived graphene, with both surfaces showing antifouling efficacy comparable to copper. Attachment of Gram-positive coccal Staphylococcus aureus was lower on the surfaces of both types of graphene compared to that on copper, with bagasse-derived graphene being particularly effective. Toxicity to planktonic bacteria estimated as a reduction in colony-forming units as a result of sample exposure showed that both graphenes effectively retarded cell replication.
Biscuits with No Added Sugar Containing Stevia, Coffee Fibre and Fructooligosaccharides Modifies α-Glucosidase Activity and the Release of GLP-1 from HuTu-80 Cells and Serotonin from Caco-2 Cells after In Vitro Digestion
Authors: Martinez-Saez Nuria , Hochkogler Christina , Somoza Veronika , Del Castillo Maria
Published: July 2017

This study assessed the in vitro effects of the bioaccessible food components released during the simulated human digestion of a coffee fibre-containing biscuit (CFB) on α-glucosidase activity, antioxidant capacity and satiety hormones. Digest of CFB presented a significantly (p < 0.05) lower amount of sugar (68.6 mg/g) and a higher antioxidant capacity (15.1 mg chlorogenic acid eq./g) than that of a sucrose-containing biscuit (SCB). The CFB significantly reduced (p < 0.05) α-glucosidase activity (IC50 = 3.3 mg/mL) compared to the SCB (IC50 = 6.2 mg/mL). Serotonin and glucagon-like peptide-1 (GLP-1) release by differentiated Caco-2 and HuTu-80 cells, respectively, was stimulated by the CFB (355% at a concentration of 0.5 mg/mL and 278% at a concentration of 0.05 mg/mL) to the same order of magnitude as those of the SCB. To summarize, the CFB was demonstrated to reduce monosaccharide bioaccessibility, to inhibit a diabetes-related digestive enzyme, and to improve the release of satiety hormones.