bluuebunny/crossref_metadata_2025 huggingface dataset:
Hydrometallurgical Process and Kinetics of Leaching Manganese from Semi-Oxidized Manganese Ores with Sucrose
Authors: Wang Yuhong , Jin Shenglong , Lv Yan , Zhang Yanjuan , Su Haifeng
Published: February 2017

The extraction of manganese from a semi-oxidized manganese ore was investigated with sucrose as the reducing agent in dilute sulfuric acid medium. The kinetics of leaching manganese from the complex ore containing MnCO3 and MnO2 was also investigated. The effects of sucrose and sulfuric acid concentrations, leaching temperature and reaction time on the total Mn (TMn), MnO2 and MnCO3 leaching were investigated. Results showed that MnCO3 could more easily react with hydrogen ions than MnO2 in ores, and MnO2 decomposition could be advantageous for MnCO3 leaching. The leaching efficiencies of 91.8% for total Mn, 91.4% for MnO2 and 96.9% for MnCO3 were obtained under the following optimized conditions: 0.035 mol/L sucrose concentration, 5 mol/L sulfuric acid concentration, 60 min of reaction time and 363.2 K of leaching temperature. In addition, it was found that the leaching process of semi-oxidized manganese ore follows the shrinking core model and the leaching rate was controlled by chemical reaction and diffusion. The apparent activation energy of the total manganese, MnO2, and MnCO3 leaching were 40.83, 40.59, and 53.33 kJ·mol−1, respectively.
Application of the Triazolization Reaction to Afford Dihydroartemisinin Derivatives with Anti-HIV Activity
Authors: Jana Sampad , Iram Shabina , Thomas Joice , Hayat Muhammad , Pannecouque Christophe , Dehaen Wim
Published: February 2017

Artemisinin and synthetic derivatives of dihydroartemisinin are known to possess various biological activities. Post-functionalization of dihydroartemisinin with triazole heterocycles has been proven to lead to enhanced therapeutic potential. By using our newly developed triazolization strategy, a library of unexplored fused and 1,5-disubstituted 1,2,3-triazole derivatives of dihydroartemisinin were synthesized in a single step. All these newly synthesized compounds were characterized and evaluated for their anti-HIV (Human Immunodeficiency Virus) potential in MT-4 cells. Interestingly; three of the synthesized triazole derivatives of dihydroartemisinin showed activities with half maximal inhibitory concentration (IC50) values ranging from 1.34 to 2.65 µM.
Adsorptive Desulfurization of Model Gasoline by Using Different Zn Sources Exchanged NaY Zeolites
Authors: Rui Jingwei , Liu Fei , Wang Rijie , Lu Yanfei , Yang Xiaoxia
Published: February 2017

A series of Zn-modified NaY zeolites were prepared by the liquid-phase ion-exchange method with different Zn sources, including Zn(NO3)2, Zn(Ac)2 and ZnSO4. The samples were tested as adsorbents for removing an organic sulfur compound from a model gasoline fuel containing 1000 ppmw sulfur. Zn(Ac)2-Y exhibited the best performance for the desulfurization of gasoline at ambient conditions. Combined with the adsorbents’ characterization results, the higher adsorption capacity of Zn(Ac)2-Y is associated with a higher ion-exchange degree. Further, the results demonstrated that the addition of 5 wt % toluene or 1-hexene to the diluted thiophene (TP) solution in cyclohexane caused a large decrease in the removal of TP from the model gasoline fuel. This provides evidence about the competition through the π-complexation between TP and toluene for adsorption on the active sites. The acid-catalyzed alkylation by 1-hexene of TP and the generated complex mixture of bulky alkylthiophenes would adsorb on the surface active sites of the adsorbent and block the pores. The regenerated Zn(Ac)2-Y adsorbent afforded 84.42% and 66.10% of the initial adsorption capacity after the first two regeneration cycles.
Biologic Stress, Oxidative Stress, and Resistance to Drugs: What Is Hidden Behind
Authors: Pantelidou Maria , Tsiakitzis Karyofyllis , Rekka Eleni , Kourounakis Panos
Published: February 2017

Stress can be defined as the homeostatic, nonspecific defensive response of the organism to challenges. It is expressed by morphological, biochemical, and functional changes. In this review, we present biological and oxidative stress, as well as their interrelation. In addition to the mediation in biologic stress (central nervous, immune, and hormonal systems) and oxidative stress, the effect of these phenomena on xenobiotic metabolism and drug response is also examined. It is concluded that stress decreases drug response, a result which seems to be mainly attributed to the induction of hepatic drug metabolizing enzymes. A number of mechanisms are presented. Structure-activity studies are also discussed. Vitamin E, as well as two synthetic novel compounds, seem to reduce both oxidative and biological stress and, consequently, influence drug response and metabolism.
Mediterranean Diet and Phase Angle in a Sample of Adult Population: Results of a Pilot Study
Authors: Barrea Luigi , Muscogiuri Giovanna , Macchia Paolo , Di Somma Carolina , Falco Andrea , Savanelli Maria , Colao Annamaria , Savastano Silvia
Published: February 2017

The Mediterranean diet is a healthy dietary pattern known to actively modulate the cell membrane properties. Phase angle (PhA) is a direct measure by Bioelectrical Impedance Analysis (BIA) used as marker of cell membrane integrity. Both food behaviour and PhA are influenced by age, sex and body weight. The aim of this study was to cross-sectionally evaluate the association between the adherence to Mediterranean diet and PhA in 1013 healthy adult patients stratified according to sex, age, and body mass index (BMI). The adherence to the Mediterranean diet was evaluated using the PREvención con DIeta MEDiterránea (PREDIMED) questionnaire. PhA was calculated by BIA phase-sensitive system (50 kHz BIA 101 RJL, Akern Bioresearch, Florence, Italy Akern). In both sexes, at ROC analysis a PREDIMED score ≥ 6 predicted a PhA beyond the median value. At the multivariate analysis, among PREDIMED score, age, and BMI, the PREDIMED score was the major determinant of PhA, explaining 44.5% and 47.3% of PhA variability, in males and females respectively (p < 0.001). A novel association was reported between the adherence to the Mediterranean diet and PhA, independently of sex, age, and body weight. This association uncovered a new potential benefit of the Mediterranean diet on health outcomes, as in both sexes higher adherence to the Mediterranean diet was associated to larger PhAs, as expression of cell membrane integrity.
Exploring the Effect of Lactium™ and Zizyphus Complex on Sleep Quality: A Double-Blind, Randomized Placebo-Controlled Trial
Authors: Scholey Andrew , Benson Sarah , Gibbs Amy , Perry Naomi , Sarris Jerome , Murray Greg
Published: February 2017

Acute, non-clinical insomnia is not uncommon. Sufferers commonly turn to short-term use of herbal supplements to alleviate the symptoms. This placebo-controlled, double-blind study investigated the efficacy of LZComplex3 (lactium™, Zizyphus, Humulus lupulus, magnesium and vitamin B6), in otherwise healthy adults with mild insomnia. After a 7-day single-blind placebo run-in, eligible volunteers (n = 171) were randomized (1:1) to receive daily treatment for 2 weeks with LZComplex3 or placebo. Results revealed that sleep quality measured by change in Pittsburgh Sleep Quality Index (PSQI) score improved in both the LZComplex3 and placebo groups. There were no significant between group differences between baseline and endpoint on the primary outcome. The majority of secondary outcomes, which included daytime functioning and physical fatigue, mood and anxiety, cognitive performance, and stress reactivity, showed similar improvements in the LZComplex3 and placebo groups. A similar proportion of participants reported adverse events (AEs) in both groups, with two of four treatment-related AEs in the LZComplex3 group resulting in permanent discontinuation. It currently cannot be concluded that administration of LZComplex3 for 2 weeks improves sleep quality, however, a marked placebo response (despite placebo run-in) and/or short duration of treatment may have masked a potential beneficial effect on sleep quality.
A Curriculum Challenge—The Need for Outcome (Competence) Descriptors
Authors: Stupans Ieva
Published: February 2017

Some outcomes around, for example, communication have been extensively theorised; others such as accountability have been relatively neglected in the teaching and learning literature. The question therefore is: if we do not have a clear understanding of the outcome, can we systematically apply good practice principles in course design such that students are able to achieve the outcomes the community and the profession expect? This paper compares and contrasts the literature around competency outcomes regarding students’ communication skills and the development of accountability and proposes a model to guide the selection of teaching and assessment approaches for accountability, based on the students’ sphere of influence.
Law, Cyborgs, and Technologically Enhanced Brains
Authors: Barfield Woodrow , Williams Alexander
Published: February 2017

As we become more and more enhanced with cyborg technology, significant issues of law and policy are raised. For example, as cyborg devices implanted within the body create a class of people with enhanced motor and computational abilities, how should the law and policy respond when the abilities of such people surpass those of the general population? And what basic human and legal rights should be afforded to people equipped with cyborg technology as they become more machine and less biology? As other issues of importance, if a neuroprosthetic device is accessed by a third party and done to edit one’s memory or to plant a new memory in one’s mind, or even to place an ad for a commercial product in one’s consciousness, should there be a law of cognitive liberty or of “neuro-advertising” that applies? This paper discusses laws and statutes enacted across several jurisdictions which apply to cyborg technologies with a particular emphasis on legal doctrine which relates to neuroprosthetic devices.
Caffeoylquinic Acids from the Aerial Parts of Chrysanthemum coronarium L.
Authors: Wan Chunpeng , Li Shanshan , Liu Lin , Chen Chuying , Fan Shuying
Published: February 2017

To elucidate the chemical compositions of the aerial parts of Chrysanthemum coronarium L., the ethanol extracts of Ch. coronarium L. were firstly isolated by the MCI-gel resin column. The caffeoylquinic acid-rich fractions were further purified by various chromatographic columns including silica gel, Sephadex LH-20, and semi-preparative HPLC to yield the compounds. The purified compounds were characterized by 1H-Nuclear Magnetic Resonance (1H-NMR), 13C-NMR, and high resolution electrospray ionisation mass spectral (HR-ESI-MS) spectroscopy. Seven caffeoylquinic acid (CQA) compounds were isolated from this plant. Their structures were clarified by spectrometric methods and identified as 3-O-caffeoylquinic acid (1), 5-O-caffeoylquinic acid (2), 4-O-caffeoylquinic acid (3), 3,4-di-O-caffeoylquinic acid (4), 1,5-di-O-caffeoylquinic acid (5), 3,5-di-O-caffeoylquinic acid (6), and 4,5-di-O-caffeoylquinic acid (7). Caffeoylquinic acids were the major constituents present in the aerial parts of Ch. coronarium L. All of the isolates except for compounds 2 and 6 were reported for the first time from this species. Moreover, compounds 3–5, and 7 were identified from the Chrysanthemum genus for the first time.
A Broad-Area Method for the Diurnal Characterisation of Upwelling Medium Wave Infrared Radiation
Authors: Hally Bryan , Wallace Luke , Reinke Karin , Jones Simon
Published: February 2017

Fire detection from satellite sensors relies on an accurate estimation of the unperturbed state of a target pixel, from which an anomaly can be isolated. Methods for estimating the radiation budget of a pixel without fire depend upon training data derived from the location’s recent history of brightness temperature variation over the diurnal cycle, which can be vulnerable to cloud contamination and the effects of weather. This study proposes a new method that utilises the common solar budget found at a given latitude in conjunction with an area’s local solar time to aggregate a broad-area training dataset, which can be used to model the expected diurnal temperature cycle of a location. This training data is then used in a temperature fitting process with the measured brightness temperatures in a pixel, and compared to pixel-derived training data and contextual methods of background temperature determination. Results of this study show similar accuracy between clear-sky medium wave infrared upwelling radiation and the diurnal temperature cycle estimation compared to previous methods, with demonstrable improvements in processing time and training data availability. This method can be used in conjunction with brightness temperature thresholds to provide a baseline for upwelling radiation, from which positive thermal anomalies such as fire can be isolated.
Marsh Loss Due to Cumulative Impacts of Hurricane Isaac and the Deepwater Horizon Oil Spill in Louisiana
Authors: Khanna Shruti , Santos Maria , Koltunov Alexander , Shapiro Kristen , Lay Mui , Ustin Susan
Published: February 2017

Coastal ecosystems are greatly endangered due to anthropogenic development and climate change. Multiple disturbances may erode the ability of a system to recover from stress if there is little time between disturbance events. We evaluated the ability of the saltmarshes in Barataria Bay, Louisiana, USA, to recover from two successive disturbances, the DeepWater Horizon oil spill in 2010 and Hurricane Isaac in 2012. We measured recovery using vegetation indices and land cover change metrics. We found that after the hurricane, land loss along oiled shorelines was 17.8%, while along oil-free shorelines, it was 13.6% within the first 7 m. At a distance of 7–14 m, land loss from oiled regions was 11.6%, but only 6.3% in oil-free regions. We found no differences in vulnerability to land loss between narrow and wide shorelines; however, vegetation in narrow sites was significantly more stressed, potentially leading to future land loss. Treated oiled regions also lost more land due to the hurricane than untreated regions. These results suggest that ecosystem recovery after the two disturbances is compromised, as the observed high rates of land loss may prevent salt marsh from establishing in the same areas where it existed prior to the oil spill.
Theoretical Analysis of an Optical Accelerometer Based on Resonant Optical Tunneling Effect
Authors: Jian Aoqun , Wei Chongguang , Guo Lifang , Hu Jie , Tang Jun , Liu Jun , Zhang Xuming , Sang Shengbo
Published: February 2017

Acceleration is a significant parameter for monitoring the status of a given objects. This paper presents a novel linear acceleration sensor that functions via a unique physical mechanism, the resonant optical tunneling effect (ROTE). The accelerometer consists of a fixed frame, two elastic cantilevers, and a major cylindrical mass comprised of a resonant cavity that is separated by two air tunneling gaps in the middle. The performance of the proposed sensor was analyzed with a simplified mathematical model, and simulated using finite element modeling. The simulation results showed that the optical Q factor and the sensitivity of the accelerometer reach up to 8.857 × 107 and 9 pm/g, respectively. The linear measurement range of the device is ±130 g. The work bandwidth obtained is located in 10–1500 Hz. The results of this study provide useful guidelines to improve measurement range and resolution of integrated optical acceleration sensors.
Middleware Design for Swarm-Driving Robots Accompanying Humans
Authors: Kim Min , Kim Sang , Kang Soon
Published: February 2017

Research on robots that accompany humans is being continuously studied. The Pet-Bot provides walking-assistance and object-carrying services without any specific controls through interaction between the robot and the human in real time. However, with Pet-Bot, there is a limit to the number of robots a user can use. If this limit is overcome, the Pet-Bot can provide services in more areas. Therefore, in this study, we propose a swarm-driving middleware design adopting the concept of a swarm, which provides effective parallel movement to allow multiple human-accompanying robots to accomplish a common purpose. The functions of middleware divide into three parts: a sequence manager for swarm process, a messaging manager, and a relative-location identification manager. This middleware processes the sequence of swarm-process of robots in the swarm through message exchanging using radio frequency (RF) communication of an IEEE 802.15.4 MAC protocol and manages an infrared (IR) communication module identifying relative location with IR signal strength. The swarm in this study is composed of the master interacting with the user and the slaves having no interaction with the user. This composition is intended to control the overall swarm in synchronization with the user activity, which is difficult to predict. We evaluate the accuracy of the relative-location estimation using IR communication, the response time of the slaves to a change in user activity, and the time to organize a network according to the number of slaves.
Steady γ-Ray Effects on the Performance of PPP-BOTDA and TW-COTDR Fiber Sensing
Authors: Planes Isabelle , Girard Sylvain , Boukenter Aziz , Marin Emmanuel , Delepine-Lesoille Sylvie , Marcandella Claude , Ouerdane Youcef
Published: February 2017

We investigated the evolution of the performances of Pulse Pre Pump-Brillouin Time Domain Analysis (PPP-BOTDA) and Tunable Wavelength Coherent Optical Time Domain Reflectometry (TW-COTDR) fiber-based temperature and strain sensors when the sensing optical fiber is exposed to two γ-ray irradiation conditions: (i) at room temperature and a dose rate of 370 Gy(SiO2)/h up to a total ionizing dose (TID) of 56 kGy; (ii) at room temperature and a dose rate of 25 kGy(SiO2)/h up to a TID of 10 MGy. Two main different classes of single-mode optical fibers have been tested in situ, radiation-tolerant ones: fluorine-doped or nitrogen-doped core fibers, as well as Telecom-grade germanosilicate ones. Brillouin and Rayleigh Sensitivities of N-Doped fibers were not reported yet, and these characterizations pave the way for a novel and alternative sensing scheme. Moreover, in these harsh conditions, our results showed that the main parameter affecting the sensor sensitivity remains the Radiation Induced Attenuation (RIA) at its operation wavelength of 1550 nm. RIA limits the maximal sensing range but does not influence the measurement uncertainty. F-doped fiber is the most tolerant against RIA with induced losses below 8 dB/km after a 56 kGy accumulated dose whereas the excess losses of other fibers exceed 22 dB/km. Both Rayleigh and Brillouin signatures that are exploited by the PPP-BOTDA and the TW-COTDR remain unchanged (within our experimental uncertainties). The strain and temperature coefficients of the various fibers under test are not modified by radiations, at these dose/dose rate levels. Consequently, this enables the design of a robust strain and temperature sensing architecture for the monitoring of radioactive waste disposals.
UW Imaging of Seismic-Physical-Models in Air Using Fiber-Optic Fabry-Perot Interferometer
Authors: Rong Qiangzhou , Hao Yongxin , Zhou Ruixiang , Yin Xunli , Shao Zhihua , Liang Lei , Qiao Xueguang
Published: February 2017

A fiber-optic Fabry-Perot interferometer (FPI) has been proposed and demonstrated for the ultrasound wave (UW) imaging of seismic-physical models. The sensor probe comprises a single mode fiber (SMF) that is inserted into a ceramic tube terminated by an ultra-thin gold film. The probe performs with an excellent UW sensitivity thanks to the nanolayer gold film, and thus is capable of detecting a weak UW in air medium. Furthermore, the compact sensor is a symmetrical structure so that it presents a good directionality in the UW detection. The spectral band-side filter technique is used for UW interrogation. After scanning the models using the sensing probe in air, the two-dimensional (2D) images of four physical models are reconstructed.
Reconfiguring Urban Sustainability Transitions, Analysing Multiplicity
Authors: Hodson Mike , Geels Frank , McMeekin Andy
Published: February 2017

Cities, and the networked infrastructures that sustain urban life, are seen as crucial sites for creating more sustainable futures. Yet, although there are many plans, the realisation of sustainable urban infrastructures on the ground is uneven. To develop better ways of understanding why this is the case, the paper makes a conceptual contribution by engaging with current understanding of urban sustainability transitions, using urban sustainable mobility as a reference point. It extends these insights to argue that urban transitions are not about technological or social innovation per se, but about how multiple innovations are experimented with, combined and reconfigured in existing urban contexts and how such processes are governed. There are potentially many ways in which urban sustainable mobility can be reconfigured contextually. Innovation is in the particular form of reconfiguration rather than individual technologies. To make analytical sense of this multiplicity, a preliminary framework is developed that offers the potential to think about urban transitions as contextual and reconfigurational. We argue that there is a need to embrace multiplicity and to understand its relationships to forms of reconfiguration, through empirical exploration and further theoretical and conceptual development. The preliminary framework is a contribution to doing so and we set out future directions for research.
Modelling Dissolved Oxygen/Sediment Oxygen Demand under Ice in a Shallow Eutrophic Prairie Reservoir
Authors: Terry Julie , Sadeghian Amir , Lindenschmidt Karl-Erich
Published: February 2017

Dissolved oxygen is an influential factor of aquatic ecosystem health. Future predictions of oxygen deficits are paramount for maintaining water quality. Oxygen demands depend greatly on a waterbody’s attributes. A large sediment–water interface relative to volume means sediment oxygen demand has greater influence in shallow systems. In shallow, ice-covered waterbodies the potential for winter anoxia is high. Water quality models offer two options for modelling sediment oxygen demand: a zero-order constant rate, or a sediment diagenesis model. The constant rate is unrepresentative of a real system, yet a diagenesis model is difficult to parameterise and calibrate without data. We use the water quality model CE-QUAL-W2 to increase the complexity of a zero-order sediment compartment with limited data. We model summer and winter conditions individually to capture decay rates under-ice. Using a semi-automated calibration method, we find an annual pattern in sediment oxygen demand that follows the trend of chlorophyll-a concentrations in a shallow, eutrophic Prairie reservoir. We use chlorophyll-a as a proxy for estimation of summer oxygen demand and winter decay. We show that winter sediment oxygen demand is dependent on the previous summer’s maximum chlorophyll-a concentrations.
Logement social et accession à la propriété
Authors: Goffette-Nagot Florence , Sidibé Modibo
Published: February 2017

L’accession à la propriété nécessite une accumulation préalable de patrimoine, notablement influencée par les dépenses de logement. En pourvoyant des loyers inférieurs à ceux du marché, le logement en HLM(Habitations à Loyer Modéré) pourrait-il accélérer le processus d’accession à la propriété de certains ménages ? Pour répondre à cette question dans le cas français, nous estimons simultanément un modèle de durée expliquant l’âge d’accession à la propriété et la probabilité d’avoir effectué un séjour en logement HLM, celle-ci étant instrumentée par la part des logements HLM dans le parc locatif de l’aire urbaine. Les estimations portent sur un échantillon tiré de l’enquête Logement 2006 de l’Insee. Selon nos résultats, l’occupation d’un logement HLM serait un facteur d’accélération de l’accession à la propriété.
Le chômage des jeunes : quel diagnostic ?
Authors: Batard Pierre-Édouard , Ferrari Nicolas , Saillard Emmanuel
Published: February 2017

Analysing Youth Unemployment.

The youth unemployment rate gives a very incomplete view of the difficulties facing young people entering the French labour market. The main obstacles are the general rigidities that penalise newentrants whatever their age. However, some young entrants– notably dropouts– experience specific problems. Short-term contracts have lasting but ambiguous effects on integration into the labour force. On the positive side, entering the labour market with a temporary contract may raise the probability of remaining employed in the medium/ long term. On the negative side, a succession of short-term contracts may make it harder to find a stable job. Lastly, young people are often forced to enter the labour market by accepting a job for which they are overqualified.
Les Tardigrades des surfaces passantes de la ville de Nice. Recherches sur la faune des Tardigrades urbains et sub-urbains de la ville de Nice (Alpes-Maritimes France)
Authors: Séméria Yves
Published: February 2017

Une précédente étude (Séméria, 1981) faisait apparaître que la ville de Nice abritait cinq espèces de tardigrades, parmi les plus communs, appartenant à quatre familles : Macrobiotidae (Macrobiotus hufelandi Schultze, M. richtersi Murray), Hypsibiidae (Ramazzottius oberhaueseri (Doyère), Milnesiidae (Milnesiurn tardigradum Doyère), et Echiniscidae (Echinisciis testudo Doyère). De nouvelles prospections portent ce nombre à sept espèces.
La cochenille blanche du mûrier, principal ravageur des cassissiers en Région Rhône-Alpes
Authors: Kreiter Philippe , Coquelet C. , Thaon Marcel
Published: February 2017

Pseudaulacaspis pentagona provoque d'importants dégâts sur cassissier en Isère. Un inventaire des ennemis naturels a été dressé. Bien que l'on constate la présence de parasitoïdes, leur efficacité semble limitée.
Synthesis and optical properties of new 5'-aryl-substituted 2,5-bis(3-decyl-2,2'-bithiophen-5-yl)-1,3,4-oxadiazoles
Authors: Kostyuchenko Anastasia Sergeevna , Zheleznova Tatyana Yu , Stasyuk Anton Jaroslavovich , Kurowska Aleksandra , Domagala Wojciech , Pron Adam , Fisyuk Alexander S
Published: February 2017

New photoluminescent donor–acceptor–donor (DAD) molecules, namely 5'-aryl-substituted 2,5-bis(3-decyl-2,2'-bithiophen-5-yl)-1,3,4-oxadiazoles were prepared by palladium-catalyzed coupling from readily available compounds such as ethyl 3-decyl-2,2'-bithiophene-5-carboxylate and aryl halides. The obtained compounds feature increasing bathochromic shifts in their emission spectra with increasing aryl-substituent size yielding blue to bluish-green emissions. At the same time, their absorption spectra are almost independent from the identity of the terminal substituent with λmax values ranging from 395 to 405 nm. The observed trends are perfectly predicted by quantum chemical DFT/TDDFT calculations carried out for these new molecules.
Can We Reconcile the TA Excess and Hotspot with Auger Observations?
Authors: Globus Noemie , Allard Denis , Parizot Etienne , Lachaud Cyril , Piran Tsvi
Published: February 2017

The Telescope Array (TA) shows a 20° hotspot as well as an excess of ultra-high-energy cosmic-rays (UHECRs) above 50 EeV when compared with the Auger spectrum. We consider the possibility that both the TA excess and hotspot are due to a dominant source in the northern sky. We carry out detailed simulations of UHECR propagation in both the intergalactic medium and the Galaxy, using different values for the intergalactic magnetic field. We consider two general classes of sources: transients and steady, adopting a mixed UHECR composition that is consistent with the one found by Auger. The spatial location of the sources is drawn randomly. We generate Auger-like and TA-like data sets from which we determine the spectrum, the sky maps, and the level of anisotropy. We find that, while steady sources are favored over transients, it is unlikely to account for all the currently available observational data. While we reproduce fairly well the Auger spectrum for the vast majority of the simulated data sets, most of the simulated data sets with a spectrum compatible with that of TA (at most a few percent depending on density model tested) show a much stronger anisotropy than the one observed. We find that the rare cases in which both the spectrum and the anisotropy are consistent require a steady source within ∼10 Mpc, to account for the flux excess, and a strong extragalactic magnetic field ∼10 nG, to reduce the excessive anisotropy.
Nebular Emission Line Ratios in z ≃ 2–3 Star-forming Galaxies with KBSS-MOSFIRE: Exploring the Impact of Ionization, Excitation, and Nitrogen-to-Oxygen Ratio∗
Authors: Strom Allison L. , Steidel Charles C. , Rudie Gwen C. , Trainor Ryan F. , Pettini Max , Reddy Naveen A.
Published: February 2017

We present a detailed study of the rest-optical (3600–7000 Å) nebular spectra of ∼380 star-forming galaxies at

, obtained with Keck/Multi-object Spectrometer for Infrared Exploration (MOSFIRE) as part of the Keck Baryonic Structure Survey (KBSS). The KBSS-MOSFIRE sample is representative of star-forming galaxies at these redshifts, with stellar masses

and star formation rates SFR = 3–1000 

yr−1. We focus on robust measurements of many strong diagnostic emission lines for individual galaxies: [O ii]λλ3727, 3729, [Ne iii]λ3869, Hβ, [O iii]

4960, 5008, [N ii]λλ 6549, 6585, Hα, and [S ii]λλ6718, 6732. Comparisons with observations of typical local galaxies from the Sloan Digital Sky Survey and between subsamples of KBSS-MOSFIRE show that high-redshift galaxies exhibit a number of significant differences in addition to the well-known offset in log([O iii]

/Hβ) and log([N ii]

/Hα). We argue that the primary difference between H ii regions in

galaxies and those at

is an enhancement in the degree of nebular excitation, as measured by [O iii]/Hβ and

[([O iii]

+[O ii]

)/Hβ]. At the same time, KBSS-MOSFIRE galaxies are ∼10 times more massive than

galaxies with similar ionizing spectra and have higher N/O (likely accompanied by higher O/H) at fixed excitation. These results indicate the presence of harder ionizing radiation fields at fixed N/O and O/H relative to typical

galaxies, consistent with Fe-poor stellar population models that include massive binaries, and highlight a population of massive, high-specific star formation rate galaxies at high redshift with systematically different star formation histories than galaxies of similar stellar mass today.
A New Compton-thick AGN in Our Cosmic Backyard: Unveiling the Buried Nucleus in NGC 1448 with NuSTAR
Authors: Annuar A. , Alexander D. M. , Gandhi P. , Lansbury G. B. , Asmus D. , Ballantyne D. R. , Bauer F. E. , Boggs S. E. , Boorman P. G. , Brandt W. N. , Brightman M. , Christensen F. E. , Craig W. W. , Farrah D. , Goulding A. D. , Hailey C. J. , Harrison F. A. , Koss M. J. , LaMassa S. M. , Murray S. S. , Ricci C. , Rosario D. J. , Stanley F. , Stern D. , Zhang W.
Published: February 2017

NGC 1448 is one of the nearest luminous galaxies (L
8–1000μm > 109
L
⊙) to ours (z = 0.00390), and yet the active galactic nucleus (AGN) it hosts was only recently discovered, in 2009. In this paper, we present an analysis of the nuclear source across three wavebands: mid-infrared (MIR) continuum, optical, and X-rays. We observed the source with the Nuclear Spectroscopic Telescope Array (NuSTAR), and combined these data with archival Chandra data to perform broadband X-ray spectral fitting (≈0.5–40 keV) of the AGN for the first time. Our X-ray spectral analysis reveals that the AGN is buried under a Compton-thick (CT) column of obscuring gas along our line of sight, with a column density of N
H(los) ≳ 2.5 × 1024 cm−2. The best-fitting torus models measured an intrinsic 2–10 keV luminosity of L

(3.5–7.6) × 1040 erg s−1, making NGC 1448 one of the lowest luminosity CTAGNs known. In addition to the NuSTAR observation, we also performed optical spectroscopy for the nucleus in this edge-on galaxy using the European Southern Observatory New Technology Telescope. We re-classify the optical nuclear spectrum as a Seyfert on the basis of the Baldwin–Philips–Terlevich diagnostic diagrams, thus identifying the AGN at optical wavelengths for the first time. We also present high spatial resolution MIR observations of NGC 1448 with Gemini/T-ReCS, in which a compact nucleus is clearly detected. The absorption-corrected 2–10 keV luminosity measured from our X-ray spectral analysis agrees with that predicted from the optical [O iii]λ5007 Å emission line and the MIR 12 μm  continuum, further supporting the CT nature of the AGN.
A Chemical Composition Survey of the Iron-complex Globular Cluster NGC 6273 (M19)*
Authors: Johnson Christian I. , Caldwell Nelson , Rich R. Michael , Mateo Mario , Bailey, III John I. , Clarkson William I. , Olszewski Edward W. , Walker Matthew G.
Published: February 2017

Recent observations have shown that a growing number of the most massive Galactic globular clusters contain multiple populations of stars with different [Fe/H] and neutron-capture element abundances. NGC 6273 has only recently been recognized as a member of this “iron-complex” cluster class, and we provide here a chemical and kinematic analysis of >300 red giant branch and asymptotic giant branch member stars using high-resolution spectra obtained with the Magellan–M2FS and VLT–FLAMES instruments. Multiple lines of evidence indicate that NGC 6273 possesses an intrinsic metallicity spread that ranges from about [Fe/H] = −2 to −1 dex, and may include at least three populations with different [Fe/H] values. The three populations identified here contain separate first (Na/Al-poor) and second (Na/Al-rich) generation stars, but a Mg–Al anti-correlation may only be present in stars with [Fe/H] ≳ −1.65. The strong correlation between [La/Eu] and [Fe/H] suggests that the s-process must have dominated the heavy element enrichment at higher metallicities. A small group of stars with low [α/Fe] is identified and may have been accreted from a former surrounding field star population. The cluster’s large abundance variations are coupled with a complex, extended, and multimodal blue horizontal branch (HB). The HB morphology and chemical abundances suggest that NGC 6273 may have an origin that is similar to ω Cen and M54.
Exploring 21 cm-Lyα Emitter Synergies for SKA
Authors: Hutter Anne , Dayal Pratika , Müller Volker , Trott Cathryn M.
Published: February 2017

We study the signatures of reionization and ionizing properties of early galaxies in the cross-correlations between the 21 cm emission from the spin-flip transition of neutral hydrogen (H i) and the underlying galaxy population. In particular, we focus on a sub-population of galaxies visible as Lyα Emitters (LAEs). With both observables simultaneously derived from a

hydrodynamical simulation (GADGET-2) snapshot post-processed with a radiative transfer code (pCRASH) and a dust model, we perform a parameter study and aim to constrain both the average intergalactic medium (IGM) ionization state (

) and the reionization topology (outside-in versus inside-out). We find that, in our model, LAEs occupy the densest and most-ionized regions resulting in a very strong anti-correlation between the LAEs and the 21 cm emission. A 1000 hr Square Kilometer Array (SKA)-LOW1—Subaru Hyper Suprime-Cam experiment can provide constraints on

, allowing us to distinguish between IGM ionization levels of 50%, 25%, 10%, and fully ionized at scales

comoving Mpc (assuming foreground avoidance for SKA). Our results support the inside-out reionization scenario where the densest knots (under-dense voids) are ionized first (last) for

. Further, 1000 hr SKA-LOW1 observations should be able to confirm the inside-out scenario by detecting a lower 21 cm brightness temperature (by about 2–10 mK) in the densest regions (≳2 arcmin scales) hosting LAEs, compared to lower-density regions devoid of them.
Galaxy and Mass Assembly (GAMA): Exploring the WISE Web in G12
Authors: Jarrett T. H. , Cluver M. E. , Magoulas C. , Bilicki M. , Alpaslan M. , Bland-Hawthorn J. , Brough S. , Brown M. J. I. , Croom S. , Driver S. , Holwerda B. W. , Hopkins A. M. , Loveday J. , Norberg P. , Peacock J. A. , Popescu C. C. , Sadler E. M. , Taylor E. N. , Tuffs R. J. , Wang L.
Published: February 2017

We present an analysis of the mid-infrared Wide-field Infrared Survey Explorer (WISE) sources seen within the equatorial GAMA G12 field, located in the North Galactic Cap. Our motivation is to study and characterize the behavior of WISE source populations in anticipation of the deep multiwavelength surveys that will define the next decade, with the principal science goal of mapping the 3D large-scale structures and determining the global physical attributes of the host galaxies. In combination with cosmological redshifts, we identify galaxies from their WISE W1 (3.4 μm) resolved emission, and we also perform a star-galaxy separation using apparent magnitude, colors, and statistical modeling of star counts. The resulting galaxy catalog has ≃590,000 sources in 60 deg2, reaching a W1 5σ depth of 31 μJy. At the faint end, where redshifts are not available, we employ a luminosity function analysis to show that approximately 27% of all WISE extragalactic sources to a limit of 17.5 mag (31 μJy) are at high redshift,

. The spatial distribution is investigated using two-point correlation functions and a 3D source density characterization at 5 Mpc and 20 Mpc scales. For angular distributions, we find that brighter and more massive sources are strongly clustered relative to fainter sources with lower mass; likewise, based on WISE colors, spheroidal galaxies have the strongest clustering, while late-type disk galaxies have the lowest clustering amplitudes. In three dimensions, we find a number of distinct groupings, often bridged by filaments and superstructures. Using special visualization tools, we map these structures, exploring how clustering may play a role with stellar mass and galaxy type.
Atmospheric Habitable Zones in Y Dwarf Atmospheres
Authors: Yates Jack S. , Palmer Paul I. , Biller Beth , Cockell Charles S.
Published: February 2017

We use a simple organism lifecycle model to explore the viability of an atmospheric habitable zone (AHZ), with temperatures that could support Earth-centric life, which sits above an environment that does not support life. To illustrate our model, we use a cool Y dwarf atmosphere, such as WISE J085510.83–0714442.5, whose 4.5–5.2 μm spectrum shows absorption features consistent with water vapor and clouds. We allow organisms to adapt to their atmospheric environment (described by temperature, convection, and gravity) by adopting different growth strategies that maximize their chance of survival and proliferation. We assume a constant upward vertical velocity through the AHZ. We found that the organism growth strategy is most sensitive to the magnitude of the atmospheric convection. Stronger convection supports the evolution of more massive organisms. For a purely radiative environment, we find that evolved organisms have a mass that is an order of magnitude smaller than terrestrial microbes, thereby defining a dynamical constraint on the dimensions of life that an AHZ can support. Based on a previously defined statistical approach, we infer that there are of the order of 109 cool Y brown dwarfs in the Milky Way, and likely a few tens of these objects are within 10 pc from Earth. Our work also has implications for exploring life in the atmospheres of temperate gas giants. Consideration of the habitable volumes in planetary atmospheres significantly increases the volume of habitable space in the galaxy.
Observational Evidence Linking Interstellar UV Absorption to PAH Molecules
Authors: Blasberger Avi , Behar Ehud , Perets Hagai B. , Brosch Noah , Tielens Alexander G. G. M.
Published: February 2017

The 2175 Å UV extinction feature was discovered in the mid-1960s, yet its physical origin remains poorly understood. One suggestion is absorption by polycyclic aromatic hydrocarbon (PAH) molecules, which is supported by theoretical molecular structure computations and by laboratory experiments. PAHs are positively detected by their 3.3, 6.2, 7.7, 8.6, 11.3, and 12.7 μm IR emission bands, which are specified by their modes of vibration. A definitive empirical link between the 2175 Å UV extinction and the IR PAH emission bands, however, is still missing. We present a new sample of hot stars that have both 2175 Å absorption and IR PAH emission. We find significant shifts of the central wavelength of the UV absorption feature, up to 2350 Å, but predominantly in stars that also have IR PAH emission. These UV shifts depend on stellar temperature in a fashion that is similar to the shifts of the 6.2 and 7.7 μm IR PAH bands, that is, the features are increasingly more redshifted as the stellar temperature decreases, but only below ∼15 kK. Above 15 kK both UV and IR features retain their nominal values. Moreover, we find a suggestive correlation between the UV and IR shifts. We hypothesize that these similar dependences of both the UV and IR features on stellar temperature hint at a common origin of the two in PAH molecules and may establish the missing link between the UV and IR observations. We further suggest that the shifts depend on molecular size, and that the critical temperature of ∼15 kK above which no shifts are observed is related to the onset of UV-driven hot-star winds and their associated shocks.
Interaction of Two Filaments in a Long Filament Channel Associated with Twin Coronal Mass Ejections
Authors: Zheng Ruisheng , Zhang Qingmin , Chen Yao , Wang Bing , Du Guohui , Li Chuanyang , Yang Kai
Published: February 2017

Using the high-quality observations of the Solar Dynamics Observatory, we present the interaction of two filaments (F1 and F2) in a long filament channel associated with twin coronal mass ejections (CMEs) on 2016 January 26. Before the eruption, a sequence of rapid cancellation and emergence of the magnetic flux has been observed, which likely triggered the ascending of the west filament (F1). The east footpoints of rising F1 moved toward the east far end of the filament channel, accompanied by post-eruption loops and flare ribbons. This likely indicated a large-scale eruption involving the long filament channel, which resulted from the interaction between F1 and the east filament (F2). Some bright plasma flew over F2, and F2 stayed at rest during the eruption, likely due to the confinement of its overlying lower magnetic field. Interestingly, the impulsive F1 pushed its overlying magnetic arcades to form the first CME, and F1 finally evolved into the second CME after the collision with the nearby coronal hole. We suggest that the interaction of F1 and the overlying magnetic field of F2 led to the merging reconnection that forms a longer eruptive filament loop. Our results also provide a possible picture of the origin of twin CMEs and show that the large-scale magnetic topology of the coronal hole is important for the eventual propagation direction of CMEs.
Charge States and FIP Bias of the Solar Wind from Coronal Holes, Active Regions, and Quiet Sun
Authors: Fu Hui , Madjarska Maria S. , Xia LiDong , Li Bo , Huang ZhengHua , Wangguan Zhipeng
Published: February 2017

Connecting in situ measured solar-wind plasma properties with typical regions on the Sun can provide an effective constraint and test to various solar wind models. We examine the statistical characteristics of the solar wind with an origin in different types of source regions. We find that the speed distribution of coronal-hole (CH) wind is bimodal with the slow wind peaking at ∼400 km s−1 and the fast at ∼600 km s−1. An anti-correlation between the solar wind speeds and the O7+/O6+ ion ratio remains valid in all three types of solar wind as well during the three studied solar cycle activity phases, i.e., solar maximum, decline, and minimum. The

range and its average values all decrease with the increasing solar wind speed in different types of solar wind. The

range (0.06–0.40, first ionization potential (FIP) bias range 1–7) for active region wind is wider than for CH wind (0.06–0.20, FIP bias range 1–3), while the minimum value of

(∼ 0.06) does not change with the variation of speed, and it is similar for all source regions. The two-peak distribution of CH wind and the anti-correlation between the speed and O7+/O6+ in all three types of solar wind can be explained qualitatively by both the wave-turbulence-driven and reconnection-loop-opening (RLO) models, whereas the distribution features of

in different source regions of solar wind can be explained more reasonably by the RLO models.
Magnetospheric Multiscale Observations of Electron Vortex Magnetic Hole in the Turbulent Magnetosheath Plasma
Authors: Huang S. Y. , Sahraoui F. , Yuan Z. G. , He J. S. , Zhao J. S. , Contel O. Le , Deng X. H. , Zhou M. , Fu H. S. , Shi Q. Q. , Lavraud B. , Pang Y. , Yang J. , Wang D. D. , Li H. M. , Yu X. D. , Pollock C. J. , Giles B. L. , Torbert R. B. , Russell C. T. , Goodrich K. A. , Gershman D. J. , Moore T. E. , Ergun R. E. , Khotyaintsev Y. V. , Lindqvist P.-A. , Strangeway R. J. , Magnes W. , Bromund K. , Leinweber H. , Plaschke F. , Anderson B. J. , Burch J. L.
Published: February 2017

We report on the observations of an electron vortex magnetic hole corresponding to a new type of coherent structure in the turbulent magnetosheath plasma using the Magnetospheric Multiscale mission data. The magnetic hole is characterized by a magnetic depression, a density peak, a total electron temperature increase (with a parallel temperature decrease but a perpendicular temperature increase), and strong currents carried by the electrons. The current has a dip in the core region and a peak in the outer region of the magnetic hole. The estimated size of the magnetic hole is about 0.23 ρ
i (∼30 ρ
e) in the quasi-circular cross-section perpendicular to its axis, where ρ
i and ρ
e are respectively the proton and electron gyroradius. There are no clear enhancements seen in high-energy electron fluxes. However, there is an enhancement in the perpendicular electron fluxes at 90° pitch angle inside the magnetic hole, implying that the electrons are trapped within it. The variations of the electron velocity components V
em and V
en suggest that an electron vortex is formed by trapping electrons inside the magnetic hole in the cross-section in the M–N plane. These observations demonstrate the existence of a new type of coherent structures behaving as an electron vortex magnetic hole in turbulent space plasmas as predicted by recent kinetic simulations.
Influence of Different Galvanic Sludge Types on the Extraction Efficiency of Chromium Ions
Authors: Mărcuș Maria Iuliana , Vlad Maria , Mîţiu A. Mihaela
Published: February 2017

Galvanic sludge resulting from wastewater treatment is a hazardous waste that can be removed by disposal only after neutralization process. A chemically complex sludge is a mixture of hydroxides of the many heavy metals such us: copper, iron, nickel, chromium, cadmium and zinc. There is worldwide, a concern to develop methods and techniques for extraction and recovery of the metal compounds from sludge out of treatment processes of wastewater from metal plating works (washing wastewater and technological solutions) in order to reinsert them into existing industrial flows or to capitalize them in other industries, leading to a significant reduction of environmental pollution.This paper presents the results of the scientific activity in the laboratory with a view to recover Cr (VI, III) from two types of galvanic sludge: a fresh sludge from wastewaters treatment by Lancy technique and an old sludge, stabilized by disposal for many years. Chromium extraction was performed by alkaline sludge oxidation to obtain salts of chromium. The extraction efficiency was 84.20 % from fresh sludge (in one stage) and 93.19% from old sludge (in two stages).