bluuebunny/crossref_metadata_2025 huggingface dataset:
Liquid Biopsies for Cancer: Coming to a Patient near You
Authors: Krishnamurthy Nithya , Spencer Emily , Torkamani Ali , Nicholson Laura
Published: January 2017

The use of circulating tumor DNA (ctDNA) as a novel and non-invasive test for the diagnosis and surveillance of cancer is a rapidly growing area of interest, with sequencing of ctDNA acting as a potential surrogate for tissue biopsy. Circulating tumor DNA has been detected incidentally during noninvasive prenatal testing and additionally in more than 75% of known cancer patients participating in ctDNA studies evaluating its sensitivity. In the setting of mutation-based targeted tumor therapy, it shows a concordance rate >80% when compared with gold-standard tissue biopsies. Through ctDNA detection and sequencing, a simple blood test becomes a liquid biopsy for cancer, surveying a patient’s entire circulation with the goal of early detection, prognostic information, personalized therapy options, and tracking for recurrence or resistance, all with fewer or no tissue biopsies. Given the recent first-ever FDA approval of a liquid biopsy, it is important for clinicians to be aware of the rapid advancements likely to bring these tests into our practices soon. Here we review the biology, clinical implications, and recent advances in circulating tumor DNA analysis.
Thermo-Mechanical Fatigue Crack Growth of RR1000
Authors: Pretty Christopher , Whitaker Mark , Williams Steve
Published: January 2017

Non-isothermal conditions during flight cycles have long led to the requirement for thermo-mechanical fatigue (TMF) evaluation of aerospace materials. However, the increased temperatures within the gas turbine engine have meant that the requirements for TMF testing now extend to disc alloys along with blade materials. As such, fatigue crack growth rates are required to be evaluated under non-isothermal conditions along with the development of a detailed understanding of related failure mechanisms. In the current work, a TMF crack growth testing method has been developed utilising induction heating and direct current potential drop techniques for polycrystalline nickel-based superalloys, such as RR1000. Results have shown that in-phase (IP) testing produces accelerated crack growth rates compared with out-of-phase (OOP) due to increased temperature at peak stress and therefore increased time dependent crack growth. The ordering of the crack growth rates is supported by detailed fractographic analysis which shows intergranular crack growth in IP test specimens, and transgranular crack growth in 90° OOP and 180° OOP tests. Isothermal tests have also been carried out for comparison of crack growth rates at the point of peak stress in the TMF cycles.
Optimal Hedging with Options and Futures against Price Risk and Background Risk
Authors: Yu Xing , Sun Hongguo
Published: January 2017

On the condition that both futures and options exist in the markets for hedging, this paper examines the optimal hedging strategy under price risk and background risk. Compared with the previous research, which has studied options hedging against basis risk and production risk being extended to options and futures hedging against price risk and background risk, we proposed a model and have taken the budget of buying options into consideration. The model is fairly general and some existing models are special cases of it. We firstly derive the necessary and sufficient conditions that guarantee the optimality of an under-hedge, a full-hedge and an over-hedge of futures for the risk-averse utility. Then, sufficient conditions are stipulated under which an over-hedge is optimal. Furthermore, we propose a program minimizing of tail conditional expectation (TCE), which is inherently equivalent to the risk measure of expected shortfall risk (ES) or the conditional VaR (CVaR) under the continuous-time framework. Finally, we find that ES, in our proposed model, is significantly smaller than the one in the model of options hedging only. Therefore, the results emphasize the need for combining futures hedging and options hedging, and it also shows that imposing background risk, whether it be additive or multiplicative, always has a great impact on the hedging efficiency. We also present some sensitivities of the relevant parameters to provide some suggestions for the investors.
Towards Flexible Transparent Electrodes Based on Carbon and Metallic Materials
Authors: Luo Minghui , Liu Yanhua , Huang Wenbin , Qiao Wen , Zhou Yun , Ye Yan , Chen Lin-Sen
Published: January 2017

Flexible transparent electrodes (FTEs) with high stability and scalability are in high demand for the extremely widespread applications in flexible optoelectronic devices. Traditionally, thin films of indium thin oxide (ITO) served the role of FTEs, but film brittleness and scarcity of materials limit its further application. This review provides a summary of recent advances in emerging transparent electrodes and related flexible devices (e.g., touch panels, organic light-emitting diodes, sensors, supercapacitors, and solar cells). Mainly focusing on the FTEs based on carbon nanomaterials (e.g., carbon nanotubes and graphene) and metal materials (e.g., metal grid and metal nanowires), we discuss the fabrication techniques, the performance improvement, and the representative applications of these highly transparent and flexible electrodes. Finally, the challenges and prospects of flexible transparent electrodes will be summarized.
Synthesis of New Nitrofluoroquinolone Derivatives with Novel Anti-Microbial Properties against Metronidazole Resistant H. pylori
Authors: Abu-Qatouseh Luay , Abu-Sini Mohammad , Mayyas Amal , Al-Hiari Yusuf , Darwish Rula , Aburjai Talal
Published: January 2017

One of the major therapeutic approaches to preventing relapse and accelerating the healing of duodenal and gastric ulcers is the eradication of Helicobacter pylori. Due to the emergence of antibiotic resistance among clinical strains of H. pylori, alternative approaches using newly discovered antimicrobial agents in combination with the standard regimens for the treatment of H. pylori are increasingly needed. The purpose of the present study was to investigate the effect of newly synthesized 8-nitroflouroqunolone derivatives when used either alone or when combined with metronidazole against metronidazole-resistant H. pylori. Based on the standard antimicrobial susceptibility testing methods and checkerboard titration assay, all of the tested compounds showed interesting antimicrobial activity against 12 clinical strains of H. pylori, with the best in vitro effect for compound 3c. In addition, synergistic and additive activities of some of the tested compounds were observed when combined with metronidazole. Furthermore, among the tested nitroflouroquinolone derivatives, compound 3b showed significant urease inhibition activity with IC50 of 62.5 µg/mL. These results suggest that 8-nitroflouroquinolone derivatives may have a useful role in combination with anti-H. pylori drugs in the management of H. pylori-associated diseases.
The Hammerhead Ribozyme: A Long History for a Short RNA
Authors: De la Peña Marcos , García-Robles Inmaculada , Cervera Amelia
Published: January 2017

Small nucleolytic ribozymes are a family of naturally occurring RNA motifs that catalyse a self-transesterification reaction in a highly sequence-specific manner. The hammerhead ribozyme was the first reported and the most extensively studied member of this family. However, and despite intense biochemical and structural research for three decades since its discovery, the history of this model ribozyme seems to be far from finished. The hammerhead ribozyme has been regarded as a biological oddity typical of small circular RNA pathogens of plants. More recently, numerous and new variations of this ribozyme have been found to inhabit the genomes of organisms from all life kingdoms, although their precise biological functions are not yet well understood.
Green Sonoextraction of Protein from Oleaginous Press Rapeseed Cake
Authors: Boukroufa Meryem , Sicaire Anne-Gaëlle , Fine Frederic , Larré Colette , Goff Aude , Jamault Véronique , Rakotomanomana Njara , Chemat Farid
Published: January 2017

In this study, extraction of soluble proteins from rapeseed cake using different conventional and innovative extraction processes in order to maximize the extraction yield has been investigated. Firstly, various extraction techniques including ultrasound, microwave, and percolation were tested to increase the protein recovery efficiency. Secondly, response surface methodology (RSM) using a central composite design (CCD) approach was applied to investigate the influence of process variables on ultrasound-assisted extraction (UAE). Statistical analysis revealed that the optimized conditions providing a protein yield of 4.24 g/100 g DM were an ultrasound power of 5.6 W·cm−2 and temperature of 45 °C. Quantitatively UAE followed by two stages of conventional extraction gave the best total protein yield of 9.81 g/100 g DM. Qualitatively, the protein efficiency ratio (PER) used as measure of the nutritive value (12S/2S ratio) which indicates protein quality in terms of S-containing essential amino acids, was similar to that of the conventional extraction method. Small amounts of protein aggregate were observed in the HPLC profile of the extract.
Antiparasitic Activity of Sulfur- and Fluorine-Containing Bisphosphonates against Trypanosomatids and Apicomplexan Parasites
Authors: Galaka Tamila , Ferrer Casal Mariana , Storey Melissa , Li Catherine , Chao María , Szajnman Sergio , Docampo Roberto , Moreno Silvia , Rodriguez Juan
Published: January 2017

Based on crystallographic data of the complexes 2-alkyl(amino)ethyl-1,1-bisphosphonates–Trypanosoma cruzi farnesyl diphosphate synthase, some linear 1,1-bisphosphonic acids and other closely related derivatives were designed, synthesized and biologically evaluated against T. cruzi, the responsible agent of Chagas disease and against Toxoplasma gondii, the etiologic agent of toxoplasmosis and also towards the target enzymes farnesyl pyrophosphate synthase of T. cruzi (TcFPPS) and T gondii (TgFPPS), respectively. The isoprenoid-containing 1,1-bisphosphonates exhibited modest antiparasitic activity, whereas the linear α-fluoro-2-alkyl(amino)ethyl-1,1-bisphosphonates were unexpectedly devoid of antiparasitic activity. In spite of not presenting efficient antiparasitic activity, these data turned out to be very important to establish a structural activity relationship.
Novel PEI/Poly-γ-Gutamic Acid Nanoparticles for High Efficient siRNA and Plasmid DNA Co-Delivery
Authors: Peng Shu-Fen , Hsu Hung-Kun , Lin Chun-Cheng , Cheng Ya-Ming , Hsu Kuang-Hsing
Published: January 2017

The efficient delivery of sufficient amounts of nucleic acids into target cells is critical for successful gene therapy and gene knockdown. The DNA/siRNA co-delivery system has been considered a promising approach for cancer therapy to simultaneously express and inhibit tumor suppressor genes and overexpressed oncogenes, respectively, triggering synergistic anti-cancer effects. Polyethylenimine (PEI) has been identified as an efficient non-viral vector for transgene expression. In this study, we created a very high efficient DNA/siRNA co-delivery system by incorporating a negatively-charged poly-γ-glutamic acid (γ-PGA) into PEI/nucleic acid complexes. Spherical nanoparticles with about 200 nm diameter were formed by mixing PEI/plasmid DNA/siRNA/γ-PGA (dual delivery nanoparticles; DDNPs) with specific ratio (N/P/C ratio) and the particles present positive surface charge under all manufacturing conditions. The gel retardation assay shows both nucleic acids were effectively condensed by PEI, even at low N/P ratios. The PEI-based DDNPs reveal excellent DNA/siRNA transfection efficiency in the human hepatoma cell line (Hep 3B) by simultaneously providing high transgene expression efficiency and high siRNA silencing effect. The results indicated that DDNP can be an effective tool for gene therapy against hepatoma.
Decomposing DInSAR Time-Series into 3-D in Combination with GPS in the Case of Low Strain Rates: An Application to the Hyblean Plateau, Sicily, Italy
Authors: Vollrath Andreas , Zucca Francesco , Bekaert David , Bonforte Alessandro , Guglielmino Francesco , Hooper Andrew , Stramondo Salvatore
Published: January 2017

Differential Interferometric SAR (DInSAR) time-series techniques can be used to derive surface displacement rates with accuracies of 1 mm/year, by measuring the one-dimensional distance change between a satellite and the surface over time. However, the slanted direction of the measurements complicates interpretation of the signal, especially in regions that are subject to multiple deformation processes. The Simultaneous and Integrated Strain Tensor Estimation from Geodetic and Satellite Deformation Measurements (SISTEM) algorithm enables decomposition into a three-dimensional velocity field through joint inversion with GNSS measurements, but has never been applied to interseismic deformation where strain rates are low. Here, we apply SISTEM for the first time to detect tectonic deformation on the Hyblean Foreland Plateau in South-East Sicily. In order to increase the signal-to-noise ratio of the DInSAR data beforehand, we reduce atmospheric InSAR noise using a weather model and combine it with a multi-directional spatial filtering technique. The resultant three-dimensional velocity field allows identification of anthropogenic, as well as tectonic deformation, with sub-centimeter accuracies in areas of sufficient GPS coverage. Our enhanced method allows for a more detailed view of ongoing deformation processes as compared to the single use of either GNSS or DInSAR only and thus is suited to improve assessments of regional seismic hazard.
COSMO-SkyMed Image Investigation of Snow Features in Alpine Environment
Authors: Paloscia Simonetta , Pettinato Simone , Santi Emanuele , Valt Mauro
Published: January 2017

In this work, X band images acquired by COSMO-SkyMed (CSK) on alpine environment have been analyzed for investigating snow characteristics and their effect on backscattering variations. Preliminary results confirmed the capability of simultaneous optical and Synthetic Aperture Radar (SAR) images (Landsat-8 and CSK) in separating snow/no-snow areas and in detecting wet snow. The sensitivity of backscattering to snow depth has not always been confirmed, depending on snow characteristics related to the season. A model based on Dense Media Radiative Transfer theory (DMRT-QMS) was applied for simulating the backscattering response on the X band from snow cover in different conditions of grain size, snow density and depth. By using DMRT-QMS and snow in-situ data collected on Cordevole basin in Italian Alps, the effect of grain size and snow density, beside snow depth and snow water equivalent, was pointed out, showing that the snow features affect the backscatter in different and sometimes opposite ways. Experimental values of backscattering were correctly simulated by using this model and selected intervals of ground parameters. The relationship between simulated and measured backscattering for the entire dataset shows slope >0.9, determination coefficient, R2 = 0.77, and root mean square error, RMSE = 1.1 dB, with p-value <0.05.
An Improved Approach for Estimating Daily Net Radiation over the Heihe River Basin
Authors: Wu Bingfang , Liu Shufu , Zhu Weiwei , Yan Nana , Xing Qiang , Tan Shen
Published: January 2017

Net radiation plays an essential role in determining the thermal conditions of the Earth’s surface and is an important parameter for the study of land-surface processes and global climate change. In this paper, an improved satellite-based approach to estimate the daily net radiation is presented, in which sunshine duration were derived from the geostationary meteorological satellite (FY-2D) cloud classification product, the monthly empirical as and bs Angstrom coefficients for net shortwave radiation were calibrated by spatial fitting of the ground data from 1997 to 2006, and the daily net longwave radiation was calibrated with ground data from 2007 to 2010 over the Heihe River Basin in China. The estimated daily net radiation values were validated against ground data for 12 months in 2008 at four stations with different underlying surface types. The average coefficient of determination (R2) was 0.8489, and the averaged Nash-Sutcliffe equation (NSE) was 0.8356. The close agreement between the estimated daily net radiation and observations indicates that the proposed method is promising, especially given the comparison between the spatial distribution and the interpolation of sunshine duration. Potential applications include climate research, energy balance studies and the estimation of global evapotranspiration.
An Integrated Microfabricated Chip with Double Functions as an Ion Source and Air Pump Based on LIGA Technology
Authors: Li Hua , Jiang Linxiu , Guo Chaoqun , Zhu Jianmin , Jiang Yongrong , Chen Zhencheng
Published: January 2017

The injection and ionization of volatile organic compounds (VOA) by an integrated chip is experimentally analyzed in this paper. The integrated chip consists of a needle-to-cylinder electrode mounting on the Polymethyl Methacrylate (PMMA) substrate. The needle-to-cylinder electrode is designed and fabricated by Lithographie, Galvanoformung and Abformung (LIGA) technology. In this paper, the needle is connected to a negative power supply of −5 kV and used as the cathode; the cylinder electrodes are composed of two arrays of cylinders and serve as the anode. The ionic wind is produced based on corona and glow discharges of needle-to-cylinder electrodes. The experimental setup is designed to observe the properties of the needle-to-cylinder discharge and prove its functions as an ion source and air pump. In summary, the main results are as follows: (1) the ionic wind velocity produced by the chip is about 0.79 m/s at an applied voltage of −3300 V; (2) acetic acid and ammonia water can be injected through the chip, which is proved by pH test paper; and (3) the current measured by a Faraday cup is about 10 pA for acetic acid and ammonia with an applied voltage of −3185 V. The integrated chip is promising for portable analytical instruments, such as ion mobility spectrometry (IMS), field asymmetric ion mobility spectrometry (FAIMS), and mass spectrometry (MS).
TWO LONG-TERM INTERMITTENT PULSARS DISCOVERED IN THE PALFA SURVEY
Authors: Lyne A. G. , Stappers B. W. , Freire P. C. C. , Hessels J. W. T. , Kaspi V. M. , Allen B. , Bogdanov S. , Brazier A. , Camilo F. , Cardoso F. , Chatterjee S. , Cordes J. M. , Crawford F. , Deneva J. S. , Ferdman R. D. , Jenet F. A. , Knispel B. , Lazarus P. , Leeuwen J. van , Lynch R. , Madsen E. , McLaughlin M. A. , Parent E. , Patel C. , Ransom S. M. , Scholz P. , Seymour A. , Siemens X. , Spitler L. G. , Stairs I. H. , Stovall K. , Swiggum J. , Wharton R. S. , Zhu W. W.
Published: January 2017

We report the discovery of two long-term intermittent radio pulsars in the ongoing Pulsar Arecibo L-Band Feed Array survey. Following discovery with the Arecibo Telescope, extended observations of these pulsars over several years at Jodrell Bank Observatory have revealed the details of their rotation and radiation properties. PSRs J1910+0517 and J1929+1357 show long-term extreme bimodal intermittency, switching between active (ON) and inactive (OFF) emission states and indicating the presence of a large, hitherto unrecognized underlying population of such objects. For PSR J1929+1357, the initial duty cycle was f
ON = 0.008, but two years later, this changed quite abruptly to f
ON = 0.16. This is the first time that a significant evolution in the activity of an intermittent pulsar has been seen, and we show that the spin-down rate of the pulsar is proportional to the activity. The spin-down rate of PSR J1929+1357 is increased by a factor of 1.8 when it is in active mode, similar to the increase seen in the other three known long-term intermittent pulsars. These discoveries increase the number of known pulsars displaying long-term intermittency to five. These five objects display a remarkably narrow range of spin-down power (

) and accelerating potential above their polar caps. If confirmed by further discoveries, this trend might be important for understanding the physical mechanisms that cause intermittency.
ON THE FORMATION OF A STABLE PENUMBRA IN A REGION OF FLUX EMERGENCE IN THE SUN
Authors: Murabito M. , Romano P. , Guglielmino S. L. , Zuccarello F.
Published: January 2017

We studied the formation of the first penumbral sector around a pore in the following polarity of the NOAA Active Region (AR) 11490. We used a high spatial, spectral, and temporal resolution data set acquired by the Interferometric BIdimensional Spectrometer operating at the NSO/Dunn Solar Telescope, as well as data taken by the Helioseismic and Magnetic Imager on board the Solar Dynamics Observatory satellite. On the side toward the leading polarity, elongated granules in the photosphere and an arch filament system (AFS) in the chromosphere are present, while the magnetic field shows a sea-serpent configuration, indicating a region of magnetic flux emergence. We found that the formation of a stable penumbra in the following polarity of the AR begins in the area facing the opposite polarity located below the AFS in the flux emergence region, different from what was found by Schlichenmaier and colleagues. Moreover, during the formation of the first penumbral sector, the area characterized by magnetic flux density larger than 900 G and the area of the umbra increase.
CALIBRATING COLUMN DENSITY TRACERS WITH GAMMA-RAY OBSERVATIONS OF THE ρ OPHIUCHI MOLECULAR CLOUD
Authors: Abrahams Ryan D. , Teachey Alex , Paglione Timothy A. D.
Published: January 2017

Diffuse gamma-ray emission from interstellar clouds results largely from cosmic ray (CR) proton collisions with ambient gas, regardless of the gas state, temperature, or dust properties of the cloud. The interstellar medium is predominantly transparent to both CRs and gamma-rays, so GeV emission is a unique probe of the total gas column density. The gamma-ray emissivity of a cloud of known column density is then a measure of the impinging CR population and may be used to map the k-scale CR distribution in the Galaxy. To this end, we test a number of commonly used column density tracers to evaluate their effectiveness in modeling the GeV emission from the relatively quiescent, nearby ρ Ophiuchi molecular cloud. We confirm that both H i and an appropriate

tracer are required to reproduce the total gas column densities probed by diffuse gamma-ray emisison. We find that the optical depth at 353 GHz (

) from Planck best reproduces the gamma-ray data overall, based on the test statistic across the entire region of interest, but near-infrared stellar extinction also performs very well, with smaller spatial residuals in the densest parts of the cloud.
STELLAR CLUSTERINGS AROUND “ISOLATED” MASSIVE YSOs IN THE LMC
Authors: Stephens Ian W. , Gouliermis Dimitrios , Looney Leslie W. , Gruendl Robert A. , Chu You-Hua , Weisz Daniel R. , Seale Jonathan P. , Chen C.-H. Rosie , Wong Tony , Hughes Annie , Pineda Jorge L. , Ott Jürgen , Muller Erik
Published: January 2017

Observations suggest that there is a significant fraction of O stars in the field of the Milky Way that appear to have formed in isolation or in low-mass clusters (<100

). The existence of these high-mass stars that apparently formed in the field challenges the generally accepted paradigm, which requires star formation to occur in clustered environments. In order to understand the physical conditions for the formation of these stars, it is necessary to observe isolated high-mass stars while they are still forming. With the Hubble Space Telescope, we observe the seven most isolated massive (>8

) young stellar objects (MYSOs) in the Large Magellanic Cloud. The observations show that while these MYSOs are remote from other MYSOs, OB associations, and even known giant molecular clouds, they are actually not isolated at all. Imaging reveals ∼100 to several hundred pre-main-sequence (PMS) stars in the vicinity of each MYSO. These previously undetected PMS stars form prominent compact clusters around the MYSOs, and in most cases they are also distributed sparsely across the observed regions. Contrary to what previous high-mass field star studies show, these observations suggest that high-mass stars may not be able to form in clusters with masses less than 100 

. If these MYSOs are indeed the best candidates for isolated high-mass star formation, then the lack of isolation is at odds with random sampling of the initial mass function. Moreover, while isolated MYSOs may not exist, we find evidence that isolated clusters containing O stars can exist, which in itself is rare.
Pregnancy-Related Changes of Antiretroviral Pharmacokinetics: An Argument for Therapeutic Drug Monitoring
Authors: Simonetti Francesco R , Cattaneo Dario , Zanchetta Nadia , Giacomet Vania , Micheli Valeria , Ciminera Nadia , Gervasoni Cristina
Published: January 2017

Here we describe a case of an HIV-infected young woman with extensive drug-resistant virus, who was successfully switched from a raltegravir-based regimen to a dolutegravir-based intensified antiretroviral regimen a few days before scheduled caesarean section because of the still detectable viral load. The trough concentrations of all antiretroviral drugs before and after delivery are also described. Our case underlines both the difficult management of young women, HIV-infected at young age with very limited treatment options and the great variability in the pregnancy-related physiological changes affecting the pharmacokinetics of antiretrovirals.
Opportunités de croissance, création de valeur et prise de contrôle d’entreprises : Un cas empirique français
Authors: Meghouar Hicham
Published: January 2017

Cette recherche analyse les motivations implicites des entreprises acquéreuses au travers de l’étude des caractéristiques financières de 48 firmes cibles françaises ayant fait l’objet d’une prise de contrôle par voie d’offre publique d’achat ou d’échange (ci-après OPA/OPE) durant la période 2001-2007. La période d’étude, non couverte par des études empiriques, correspond à la récente vague observée sur le marché des prises de contrôle et freinée par la crise financière des Subprimes. Les résultats empiriques montrent que les acquéreurs visent des entreprises cibles aux opportunités économiques et financières importantes, ce qui conforte les décisions d’acquisitions, prises par l’acquéreur, avec la volonté de réaliser des synergies. Les présents résultats confirment le rôle disciplinaire des offres publiques et confortent les travaux empiriques antérieurs.
Innovation et industrialisation : Un enjeu pour la France
Authors: Dou Henri
Published: January 2017

Dans un monde concurrentiel, l’importance de l’innovation et du transfert des compétences universitaires vers l’industrie est analysée de manière critique. L’évaluation des chercheurs et le mode de gestion financière de la recherche n’en font plus nécessairement des facteurs de développement. Les critères d’évaluation des chercheurs et des laboratoires les éloignent des préoccupations locales et entre autres d’une aide efficace qui pourrait être apportée aux PME/PMI génératrices d’emplois. La disparition progressive de l’influence française au niveau de l’expertise internationale est analysée brièvement mettant en évidence l’absence d’une politique cohérente dans ce domaine. Si la France a des atouts certains, des politiques aux effets contradictoires minimisent ces derniers. Une recherche de consensus doit être systématique pour aboutir à une politique industrielle ciblée. Il est aussi souligné dans cet article l’importance du temps et de l’espace qui doit être prise en compte par un personnel politique souvent technologiquement acculturé ce qui remet en cause le rôle de l’Etat actionnaire.
Procedural moderate sedation with ketamine in pediatric critical care unit
Authors: Hazwani Tarek R , Alem Hala Al
Published: January 2017

Objective: To evaluate the safety and efficacy of moderate sedation in the Pediatric Intensive Care Unit (PICU) settings according to moderate sedation protocol using ketamine and midazolam and to determine areas for the improvement in our clinical practice. Settings and Design: A retrospective study was conducted in the PICU. Materials and Methods: Retrospective chart review was performed for patients who had received moderate sedation between January and the end of December 2011 and who are eligible to inclusion criteria. Results: In this study, 246 moderate sedation sessions were included. 5.3% were in infant age, while 94.7% were children (1-14 years). Their gender distributed as 59.8% males and 40.2% females. The majority of them had hematology-oncology disease nature, i.e., 80.89% (n = 199). Lumbar puncture accounted for 65.3% (n = 160) of the producers; the rests were bone marrow aspiration 32.7%, endoscopy 8.2%, and colonoscopy 2.9%. Two doses of ketamine (1-1.5 mg/kg) to achieve moderate sedation during the procedure were given to 44.1% (n = 108) of the patients. One dose of midazolam was given to 77.2% (n = 190), while 1.22% (n = 3) of sessions of moderate sedation was done without any dose of midazolam. Adverse events including apnea, laryngeal spasm, hypotension, and recovery agitation were observed during moderate sedation sessions, and it has been noticed in four sessions, i.e., 1.6%, which were mild to moderate and managed conservatively. Conclusion: Moderate sedation in the PICU using ketamine and midazolam is generally safe with minimal side effects as moderate sedation sessions were conducted by pediatric intensivist in highly monitored and equipped environment.
Very severe spinal muscular atrophy (Type 0)
Authors: Dakhoul Suleiman Al
Published: January 2017

This case report describes a rare phenotype of very severe spinal muscular atrophy (SMA) in a newborn who presented with reduced fetal movements in utero and significant respiratory distress at birth. The patient was homozygously deleted for exon 7 and exon 8 of the survival motor neuron gene 1. Very severe SMA should be considered in the differential diagnosis of respiratory distress at birth, and more research should be dedicated to investigate the genetic determinants of its widely variable phenotypes.
Molecular composition and volatility of isoprene photochemical oxidation secondary organic aerosol under low- and high-NOx conditions
Authors: D'Ambro Emma L. , Lee Ben H. , Liu Jiumeng , Shilling John E. , Gaston Cassandra J. , Lopez-Hilfiker Felipe D. , Schobesberger Siegfried , Zaveri Rahul A. , Mohr Claudia , Lutz Anna , Zhang Zhenfa , Gold Avram , Surratt Jason D. , Rivera-Rios Jean C. , Keutsch Frank N. , Thornton Joel A.
Published: January 2017

Abstract. We present measurements of secondary organic aerosol (SOA) formation from isoprene photochemical oxidation in an environmental simulation chamber at a variety of oxidant conditions and using dry neutral seed particles to suppress acid-catalyzed multiphase chemistry. A high-resolution time-of-flight chemical ionization mass spectrometer (HR-ToF-CIMS) utilizing iodide-adduct ionization coupled to the Filter Inlet for Gases and Aerosols (FIGAERO) allowed for simultaneous online sampling of the gas and particle composition. Under high-HO2 and low-NO conditions, highly oxygenated (O : C  ≥  1) C5 compounds were major components (∼ 50 %) of SOA. The SOA composition and effective volatility evolved both as a function of time and as a function of input NO concentrations. Organic nitrates increased in both the gas and particle phases as input NO increased, but the dominant non-nitrate particle-phase components monotonically decreased. We use comparisons of measured and predicted gas-particle partitioning of individual components to assess the validity of literature-based group-contribution methods for estimating saturation vapor concentrations. While there is evidence for equilibrium partitioning being achieved on the chamber residence timescale (5.2 h) for some individual components, significant errors in group-contribution methods are revealed. In addition, > 30 % of the SOA mass, detected as low-molecular-weight semivolatile compounds, cannot be reconciled with equilibrium partitioning. These compounds desorb from the FIGAERO at unexpectedly high temperatures given their molecular composition, which is indicative of thermal decomposition of effectively lower-volatility components such as larger molecular weight oligomers.
Higher measured than modeled ozone production at increased NOx levels in the Colorado Front Range
Authors: Baier Bianca , Brune William , Miller David , Blake Donald , Long Russell , Wisthaler Armin , Cantrell Christopher , Fried Alan , Heikes Brian , Brown Steven , McDuffie Erin , Flocke Frank , Apel Eric , Kaser Lisa , Weinheimer Andrew
Published: January 2017

Abstract. Chemical models must accurately calculate the ozone formation rate, P(O3), to accurately predict ozone levels and test mitigation strategies. However, model chemical mechanisms can contain large uncertainties in P(O3) calculations, which can create uncertainties in ozone forecasts especially during the summertime when P(O3) can be high. One way to test mechanisms is to evaluate model P(O3) using direct measurements. During summer 2014, the Measurement of Ozone Production Sensor (MOPS) measured net P(O3) in Golden, CO, approximately 25 km west of Denver along the Colorado Front Range. Net P(O3) was compared to rates calculated by a photochemical box model using a lumped and a more explicit chemical mechanism. Observed P(O3) was up to a factor of two higher than that modeled during early morning hours when nitric oxide (NO) levels were high, contrary to traditional ozone chemistry theory. This disagreement may be due to model underestimation of hydroperoxyl (HO2) radicals relative to observations at high NO levels. These additional peroxyl radicals could come from the MOPS chamber chemistry or from missing volatile organic compounds co-emitted with NOx; additional cycling of OH into HO2 through reactions involving nitric oxide provides an alternate explanation for higher measured than modeled P(O3). Although the MOPS measurements are new, comparisons of observed and modeled P(O3) in NO space show a similar behavior to other comparisons between P(O3) derived from measurements and modeled P(O3). These comparisons can have implications for the sensitivity of P(O3) to nitrogen oxides and volatile organic compounds during morning hours, and can possibly affect ozone reduction strategies for the region surrounding Golden, CO in addition to other urban and suburban areas that are in non-attainment with national ozone regulations.
Carbon monoxide column retrieval for clear-sky and cloudy atmospheres: a full-mission data set from SCIAMACHY 2.3 μm reflectance measurements
Authors: Borsdorff Tobias , aan de Brugh Joost , Hu Haili , Nédélec Philippe , Aben Ilse , Landgraf Jochen
Published: January 2017

Abstract. We discuss the retrieval of carbon monoxide (CO) vertical column densities from clear-sky and cloud contaminated 2311–2338 nm reflectance spectra measured by the Scanning Imaging Absorption Spectrometer for Atmospheric Chartography (SCIAMACHY) from January 2003 until the end of the mission in April 2012. These data was processed with the Shortwave Infrared CO Retrieval algorithm SICOR that we developed for the operational data processing of the Tropospheric Monitoring Instrument (TROPOMI) that will be launched on ESA’s Sentinel-5 Precursor (S5P) mission. This study complements previous work that was limited to clear-sky observations over land. Over the oceans, CO is estimated from cloudy-sky measurements only, which is an important addition to the SCIAMACHY clear-sky CO data set as shown by NDACC and TCCON measurements at coastal sites. For Ny-Ålesund, Lauder, Mauna Loa, and Reunion, a validation of SCIAMACHY clear-sky retrievals is not meaningful because of the high retrieval noise and the few collocations at these sites. This improves significantly when considering cloudy-sky observations, where we find a low mean bias b = ±6.0 ppb and a strong correlation between the validation data set and the SCIAMACHY data sets with a mean Pearson correlation coefficient r = 0.7. Also for land observations, cloudy-sky CO retrievals present an interesting complement to the clear-sky data set, which is less sensitive to the spatial representativeness of the satellite and validation measurement. For example, at the cities Teheran and Beijing the agreement of SCIAMACHY clear-sky CO observations with MOZAIC/IAGOS airborne measurements is poor with a mean bias of b = 171.2 ppb and 57.9 ppb because of local CO pollution, which cannot be captured by SCIAMACHY. The validation improves significantly for cloudy sky retrievals with b = 52.3 ppb and 5.0 ppb, respectively. This is due to a reduced retrieval sensitivity to CO below the cloud and so to the altitude range, which is mostly affected by strong local surface emissions. At the less urbanized region around the airportWindhoek, local CO pollution is less prominent and so MOZAIC/IAGOS measurements agree well with SCIAMACHY clear-sky retrievals with a mean bias of b = 15.5 ppb, but can be even further improved considering cloudy SCIAMACHY observations with a mean CO bias of b = 0.2 ppb. Overall the cloudy-sky CO retrievals from SCIAMACHY short wave infrared measurements present a valuable addition to the clear-sky only data set. Moreover, the study represents the first application of the S5P algorithm for operational CO data processing on cloudy observations prior to the launch of the S5P mission.
Transport and storage of anthropogenic C in the Subpolar North Atlantic:
Model–Data comparison
Authors: Racapé Virginie , Zunino Patricia , Lherminier Pascale , Mercier Herlé , Bopp Laurent , Gehlen Marion
Published: January 2017

Abstract. The North Atlantic Ocean is a major sink region for anthropogenic carbon (Cant) and a major contributor to its storage. While it is in general agreed that the intensity of the meridional overturning circulation (MOC) modulates uptake, transport and storage of Cant in the North Atlantic Subpolar Ocean, processes controlling their recent variability and 21st century evolution remain uncertain. This study aims to investigate the relationship between the transport of Cant across the Greenland-Portugal OVIDE section and the storage of Cant in the North Atlantic Subpolar Ocean over the past 44 years. Its relies on the combined analysis of a multi-annual data set (OVIDE program) and output from a global biogeochemical ocean general circulation model (NEMO/PISCES) at 1/2° spatial resolution forced by the atmospheric reanalysis Drakkar Forcing Set 4. The skill of the model to reproduce observed physical and biogeochemical characteristics, as well as their year-to-year variability is assessed over the period covered by observations. While the analysis of the 44 year long hindcast simulation reveals that the interannual variability of the storage rate of Cant is controlled by the northward transport during low NAO phases, as opposed to the air-sea flux during strong NAO phases, the progressive and continuous increase of the subpolar North Atlantic Cant inventory over the period 1958–2012 is driven by the regional uptake of Cant from the atmosphere. Our results suggest thus an increase of the Cant inventory in this region over the 21 st century assuming unabated emissions of CO2 and MOC fluctuation within observed boundaries.
Spring temperature variability over Turkey since 1800 CE reconstructed from a broad network of tree-ring data
Authors: Köse Nesibe , Güner H. Tuncay , Harley Grant L. , Guiot Joel
Published: January 2017

Abstract. The meteorological observational period in Turkey, which starts ca. 1930 CE, is too short for understanding long-term climatic variability. Tree rings have been used intensively as proxy records to understand summer precipitation history of the region, primarily because they have a dominant precipitation signal. Yet, the historical context of temperature variability is unclear. Here, we used higher-order principle components of a network of 23 tree-ring chronologies to provide a high-resolution spring (March–April) temperature reconstruction over Turkey during the period 1800–2002. The reconstruction model accounted for 67 % (Adj. R2 =  0.64, p < 0.0001) of the instrumental temperature variance over the full calibration period (1930–2002). The reconstruction is punctuated by a temperature increase during the 20th century; yet extreme cold and warm events during the 19th century seem to eclipse conditions during the 20th century. We found significant correlations between our March–April spring temperature reconstruction and existing gridded spring temperature reconstructions for Europe over Turkey and southeastern Europe. Moreover, the precipitation signal obtained from the tree-ring network (first principle component) showed highly significant correlations with gridded summer drought index reconstruction over Turkey and Mediterranean countries. Our results showed that, beside the dominant precipitation signal, a temperature signal can be extracted from tree-ring series and they can be useful proxies in reconstructing past temperature variability.
Transfer of environmental signals from surface to the underground at Ascunsă Cave, Romania
Authors: Drăgușin Virgil , Balan Sorin , Blamart Dominique , Forray Ferenc L. , Marin Constantin , Mirea Ionuț , Nagavciuc Viorica , Perșoiu Aurel , Tîrlă Laura , Tudorache Alin , Vlaicu Marius
Published: January 2017

Abstract. We present here the results of a four year environmental monitoring program at Ascunsă Cave, Romania, intended to understand how climate information is transferred through the karst system and archived in speleothems. The air temperature inside the cave is around 7 °C, with slight differences between the upper and lower parts of the main passage. Relative humidity measurements were hampered by condensation on the capacitive sensors we used, thus we consider it to be close to 100 %. The local meteoric water line (δ2H = 7.7 δ18O + 10.1), constructed using monthly aggregated rainfall samples, is similar to the global one, revealing the Atlantic as the strongly dominant vapor source. The δ2H excess values, as high as 17 ‰, indicate that precipitation has an important evaporative component, possibly given by moisture recycling over the European continent. CO2 concentrations in cave air have a seasonal signal, with summer minima and winter maxima. This might be indicative of an organic matter reservoir deep within the epikarst that continues to decompose over the winter, possibly modulated by seasonal differences in cave ventilation. The maximum values of CO2 show a rise after the summer of 2014, from around 2000 ppm to about 3500 ppm. An analogous rise is seen in drip water stable isotopes and chemical elements such as Sr and Mg. The variability of stable isotopes and chemical elements is similar at all points inside the cave, indicating that they are draining a homogenous reservoir. Using two newly designed types of water/air equilibrators we were able to determine drip water dissolved CO2, by measuring its concentration in the equilibrator headspace and then using Henry's law to calculate its concentration in water. This opens the possibility of continuous data logging using infrared technology without the need of costly and less reliable chemical determinations.
Tangjiaxi Landslide and Impulse Wave Analysis in Zhexi Reservoir of China by Granular Flow Coupling Model
Authors: Huang Bolin , Yin Yueping , Wang Shichang , Liu Guangning , Tan Jianmin
Published: January 2017

Abstract. Rocky granular flow usually forms after rocky bank slopes are failed and rushes into rivers at a high velocity, causing impulse wave disasters. Currently, the granular mass/water coupling study is an important trend in the field of landslide-induced impulse wave. In the paper, a full coupling numerical model for landslide-induced impulse wave is built based on non-coherent granular flow equation. In this model, Mih equation for continuous non-coherent granular flow controls the movement of sliding mass, two-phase flow equation regulates the interaction between sliding mass and water, Re-Normalisation Group (RNG) turbulence model governs the movement of water body. Taking Tangjiaxi landslide as an example, which is located at Zhexi Reservoir in Hunan Province, China, the motion characteristics of Tangjiaxi landslide and the following impulse wave process were analyzed by the coupling model, and the validity of this model was checked. On July 16, 2014, rocky blocks debris flow was formed after the failure of Tangjiaxi landslide, damming Tangjiaxi stream and thus causing an impulse wave disaster with which left three persons dead and nine persons missing. The full coupling numerical analysis showed that after the failure of Tangjiaxi rockslide, rocky granular flows impacted the water at the maximum velocity of about 22.5 m/s, with waves propagating at the maximum celerity of up to 12 m/s. The deposited topographic modeled is similar to that accumulated in the actual situation. The maximum run-up calculated is 21.8 m, close to the value of 22.7 m obtained in the field survey. A series of run-up values in the field survey matches well with the calculated values. Therefore, the full coupling numerical model built in this study can be used to simulate impulse waves generated by rocky granular flows.
Numerical modeling of the 2013 meteorite entry in Chebarkul Lake,
Russia
Authors: Kozelkov Andrey , Kurkin Andrey , Pelinovsky Efim , Kurulin Vadim , Tyatyushkina Elena
Published: January 2017

Abstract. The results of the numerical simulation of possible hydrodynamic perturbations in Lake Chebarkul (Russia) as a consequence of the meteorite fall of 2013 (Feb. 15) are presented. The numerical modeling is based on the Navier-Stokes equations for a two-phase fluid. The results of the simulation of a meteorite entering the water at an angle of 20 degrees are given. Numerical experiments are carried out both when the lake is covered with ice and when it isn't. The estimation of size of the destructed ice cover is made. It is shown that the size of the observed ice-hole at the place of the meteorite fall is in good agreement with the theoretical predictions, as well as with other estimates. The heights of tsunami waves generated by a small meteorite entering the lake are small enough (a few centimeters) according to the estimations. However, the danger of a tsunami of meteorite or asteroid origin should not be underestimated.