bluuebunny/crossref_metadata_2025 huggingface dataset:
When the Tides Come, Where Will We Go?: Modeling the Impacts of Sea Level Rise on the Greater Boston, Massachusetts, Transport and Land Use System
Authors: Han Yafei , Zegras P. Christopher , Rocco Victor , Dowd Michael , Murga Mikel
Published: March 2017

For coastal urban areas, an increase in flooding is one of the clearest climate change threats. The research presented in this paper demonstrates how a land use–transport model can be used to forecast the short- and longer-term impacts of a potential 4-ft sea level rise in greater Boston, Massachusetts, by 2030. The short-term scenario represents the immediate transport system response to inundation, which provides a measure of resiliency in the case of an extreme event, such as a storm surge. In the short run, the results reveal that transit captive users will suffer more. Transit, in general, displays less resiliency, at least in part because of the center city’s vulnerability and Boston’s radial transit system. Trip distances would modestly decrease, and average travel speeds would go down by more than 50%. Rail transit ridership would be decimated, and overall transit usage would go down by 66%. The longer-term scenario predicts how households and firms would prefer to relocate in the so-called new equilibrium when more than 10 mi2 of land disappears and the transport network inundations become permanent. Assuming no supply constraints, new residential growth centers would emerge on the peripheries of the inundated zones, primarily in the inner-core suburbs. Some regional urban centers and traditional industrial towns would boom. Firms would be hit harder, because of their heavy concentration in the inner core; firm relocation would largely follow households. Transit usage would again be decimated, but walking trips would increase. Results, however, should be viewed as cautious speculation.
Immunoglobulin G1 and G2 profile in children with Down syndrome
Authors: Saha Supti Prava , Khan Monsura , Chowdhury Ashesh Kumar
Published: March 2017

Background and objectives: It is well known that children with Down syndrome (DS) suffer from frequent infections. There is an association of certain IgG subclass abnormalities with the predisposition to recurrent infection of the respiratory tract. Therefore, the study was conducted to determine the immunoglobulin G1 and G2 (IgG1, IgG2) profile in children with DS.Material and methods: Forty children between the ages of 6 months to 12 years with DS (47 XX/XY, +21) attending the Department of Immunology, BIRDEM were enrolled in the study. Age and sex matched 30 healthy normal children with 46 XX/XY were included as control. Enrolled DS and healthy children were divided into two age groups namely 6 months to 6 years and 7 years to 12 years. Serum IgG1 and IgG2 concentrations were determined by enzyme linked immunosorbent assay (ELISA) method.Results: The mean serum IgG1 concentrations of children with DS in both age groups did not differ significantly from that of normal healthy children. But the IgG2 level was significantly less (p<0.003 and p<0.004) in both age groups of children with DS compared to that of control healthy children.Conclusion: The study has demonstrated that the serum IgG2 level was significantly less in children with DS than that of matched normal healthy control children while there was no deficiency of IgG1.IMC J Med Sci 2017; 11(1): 1-4
Facial nerve paralysis due to intra aural tick infestation: a case report
Authors: Hamat Nurul Atikah Binti , Salahuddin Zulkiflee , Salim Rosdan
Published: March 2017

Tick infestation in the ear canal may have variable clinical presentations. We present here a case of facial nerve paralysis in a 73 years old lady due to intra aural tick infestation. The patient presented with left otalgia, vertigo and left sided facial asymmetry. The case could be confused with cerebrovascular accident or transient ischemic attack.IMC J Med Sci 2017; 11(1): 29-31
A Review of Sustainability Enhancements in the Beef Value Chain: State-of-the-Art and Recommendations for Future Improvements
Authors: Maia de Souza Danielle , Petre Ruaraidh , Jackson Fawn , Hadarits Monica , Pogue Sarah , Carlyle Cameron , Bork Edward , McAllister Tim
Published: March 2017

The beef sector is working towards continually improving its sustainability in order to achieve environmentally, socially and economically desirable outcomes, all of which are of increasing concern to consumers. In this context, the Global Roundtable for Sustainable Beef (GRSB) provides guidance to advance the sustainability of the beef industry, through increased stakeholder engagement and the formation of national roundtables. Recently, the 2nd Global Conference on Sustainable Beef took place in Banff, Alberta, Canada, hosted by the GRSB and the Canadian Roundtable for Sustainable Beef. Conference attendees discussed the various initiatives that are being developed to address aspects of beef sustainability. This paper reviews the main discussions that occurred during this event, along with the key lessons learned, messages, and strategies that were proposed to improve the sustainability of the global beef industry.
Future Climate of Colombo Downscaled with SDSM-Neural Network
Authors: Dorji Singay , Herath Srikantha , Mishra Binaya
Published: March 2017

The Global Climate Model (GCM) run at a coarse spatial resolution cannot be directly used for climate impact studies. Downscaling is required to extract the sub-grid and local scale information. This paper investigates if the artificial neural network (ANN) is better than the widely-used regression-based statistical downscaling model (SDSM) for downscaling climate for a site in Colombo, Sri Lanka. Based on seasonal and annual model biases and the root mean squared error (RMSE), the ANN performed better than the SDSM for precipitation. This paper proposes a novel methodology for improving climate predictions by combining SDSM with neural networks. This method will allow a user to apply SDSM with a neural network model for higher skills in downscaling. The study uses the Canadian Earth System Model (CanESM2) of the IPCC Fifth Assessment Report, reanalysis from the National Center for Environmental Prediction (NCEP), and the Asian Precipitation Highly Resolved Observational Data Integration towards Evaluation of Water Resources (APHRODITE) project data as the observation. SDSM and the focused time-delayed neural network (TDNN) models are used for the downscaling. The projected annual increase for Representative Concentration Pathway (RCP) is 8.5; the average temperature is 2.83 °C (SDSM) and 3.03 °C (TDNN), and rainfall is 33% (SDSM) and 63% (TDNN) for 2080’s.
Review of Antibacterial Activity of Titanium-Based Implants’ Surfaces Fabricated by Micro-Arc Oxidation
Authors: He Xiaojing , Zhang Xiangyu , Wang Xin , Qin Lin
Published: March 2017

Ti and its alloys are the most commonly-used materials for biomedical applications. However, bacterial infection after implant placement is still one of the significant rising complications. Therefore, the application of the antimicrobial agents into implant surfaces to prevent implant-associated infection has attracted much attention. Scientific papers have shown that inorganic antibacterial metal elements (e.g., Ag, Cu, Zn) can be introduced into implant surfaces with the addition of metal nanoparticles or metallic compounds into an electrolyte via micro-arc oxidation (MAO) technology. In this review, the effects of the composition and concentration of electrolyte and process parameters (e.g., voltage, current density, oxidation time) on the morphological characteristics (e.g., surface morphology, bonding strength), antibacterial ability and biocompatibility of MAO antimicrobial coatings are discussed in detail. Anti-infection and osseointegration can be simultaneously accomplished with the selection of the proper antibacterial elements and operating parameters. Besides, MAO assisted by magnetron sputtering (MS) to endow Ti-based implant materials with superior antibacterial ability and biocompatibility is also discussed. Finally, the development trend of MAO technology in the future is forecasted.
Occupational Respiratory Diseases of Miners from Two Gold Mines in Ghana
Authors: Ayaaba Esther , Li Yan , Yuan Jiali , Ni Chunhui
Published: March 2017

Objective: This study investigated respiratory disorders among gold miners in Ghana, a sub-Saharan African country. Material and Methods: A cross-sectional exploratory design that employed quantitative methods was conducted among 1001 male workers from the Obuasi and Tarkwa mines from December 2015 to April 2016. A total of 1001 workers, consisting of 505 and 496 underground and surface miners, respectively, were involved. The cross-sectional descriptive design was used because data was collected from participants of different experiences by selected participants at a time. Results: The study found significant association between age, educational background, marital status and drinking alcohol on respiratory disorders. The prevalence of asthma, pneumonia, bronchitis and emphysema were respectively 47.55%, 14.29%, 9.69% and 5.10%. Coughing was the most cited respiratory symptom (35.4%). Conclusions: The study documents important evidence on the level of respiratory disorders among miners in Ghana. Instituting appropriate health education interventions and improving the working environment is critical to improving the overall health and preventing respiratory disorders among miners.
Efficient Geometric Pruning Strategies for Continuous Skyline Queries
Authors: Zheng Jiping , Chen Jialiang , Wang Haixiang
Published: March 2017

The skyline query processing problem has been well studied for many years. The literature on skyline algorithms so far mainly considers static query points on static attributes. With the popular usage of mobile devices along with the increasing number of mobile applications and users, continuous skyline query processing on both static and dynamic attributes has become more pressing. Existing efforts on supporting moving query points assume that the query point moves with only one direction and constant speed. In this paper, we propose continuous skyline computation over an incremental motion model. The query point moves incrementally in discrete time steps with no restrictions and predictability. Geometric properties over incremental motion denoted by a kinetic data structure are utilized to prune the portion of data points not included in final skyline query results. Various geometric strategies are asymptotically proposed to prune the querying dataset, and event-driven mechanisms are adopted to process continuous skyline queries. Extensive experiments under different data sets and parameters demonstrate that the proposed method is robust and more efficient than multiple snapshots of I/O optimal branch-and-bound skyline (BBS) skyline queries.
Survivin and NAIP in Human Benign Prostatic Hyperplasia: Protective Role of the Association of Serenoa repens, Lycopene and Selenium from the Randomized Clinical Study
Authors: Morgia Giuseppe , Micali Antonio , Rinaldi Mariagrazia , Irrera Natasha , Marini Herbert , Puzzolo Domenico , Pisani Antonina , Privitera Salvatore , Russo Giorgio , Cimino Sebastiano , Ieni Antonio , Trichilo Vincenzo , Altavilla Domenica , Squadrito Francesco , Minutoli Letteria
Published: March 2017

Benign prostatic hyperplasia (BPH) treatment includes the apoptosis machinery modulation through the direct inhibition of caspase cascade. We previously demonstrated that Serenoa repens (Ser) with lycopene (Ly) and selenium (Se) reawakened apoptosis by reducing survivin and neuronal apoptosis inhibitory protein (NAIP) levels in rats. The aim of this study was to evaluate the effectiveness of Ser-Se-Ly association on survivin and NAIP expression in BPH patients. Ninety patients with lower urinary tract symptoms (LUTS) due to clinical BPH were included in this randomized, double-blind, placebo-controlled trial. Participants were randomly assigned to receive placebo (Group BPH + placebo, n = 45) or Ser-Se-Ly association (Group BPH + Ser-Se-Ly; n = 45) for 3 months. At time 0, all patients underwent prostatic biopsies. After 3 months of treatment, they underwent prostatic re-biopsy and specimens were collected for molecular, morphological, and immunohistochemical analysis. After 3 months, survivin and NAIP were significantly decreased, while caspase-3 was significantly increased in BPH patients treated with Ser-Se-Ly when compared with the other group. In BPH patients treated with Ser-Se-Ly for 3 months, the glandular epithelium was formed by a single layer of cuboidal cells. PSA showed high immunoexpression in all BPH patients and a focal positivity in Ser-Se-Ly treated patients after 3 months. Evident prostate specific membrane antigen (PSMA) immunoexpression was shown in all BPH patients, while no positivity was present after Ser-Se-Ly administration. Ser-Se-Ly proved to be effective in promoting apoptosis in BPH patients.
Microstructure Evolution and Biodegradation Behavior of Laser Rapid Solidified Mg–Al–Zn Alloy
Authors: He Chongxian , Bin Shizhen , Wu Ping , Gao Chengde , Feng Pei , Yang Youwen , Liu Long , Zhou Yuanzhuo , Zhao Mingchun , Yang Sheng , Shuai Cijun
Published: March 2017

The too fast degradation of magnesium (Mg) alloys is a major impediment hindering their orthopedic application, despite their superior mechanical properties and favorable biocompatibility. In this study, the degradation resistance of AZ61 (Al 6 wt. %, Zn 1 wt. %, remaining Mg) was enhanced by rapid solidification via selective laser melting (SLM). The results indicated that an increase of the laser power was beneficial for enhancing degradation resistance and microhardness due to the increase of relative density and formation of uniformed equiaxed grains. However, too high a laser power led to the increase of mass loss and decrease of microhardness due to coarsened equiaxed grains and a reduced solid solution of Al in the Mg matrix. In addition, immersion tests showed that the apatite increased with the increase of immersion time, which indicated that SLMed AZ61 possessed good bioactivity.
Preparation of Highly Pure Vanadyl Sulfate from Sulfate Solutions Containing Impurities of Iron and Aluminum by Solvent Extraction Using EHEHPA
Authors: Li Dan , Chen Desheng , Zhang Guozhi , Zhao Hongxin , Qi Tao , Wang Weijing , Wang Lina , Liu Yahui
Published: March 2017

The preparation of highly pure vanadyl sulfate from sulfate solutions containing impurities of iron and aluminumwas investigated by solvent extraction with 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester (EHEHPA) and tri-n-butyl phosphate (TBP) as the phase modifier. The extraction and stripping conditions of vanadium (IV) and its separation from iron and aluminum were optimized. Under the optimal extraction conditions, the extraction of vanadium (IV) and iron were 68% and 53%, respectively, while only 2% aluminum was extracted in a single contact, suggesting good separation of vanadium (IV) from aluminum. Sulfuric acid solution was used for the stripping. Nearly 100% vanadium (IV) and 95% aluminum were stripped, while only 10% iron was stripped under the optimal stripping conditions in a single contact, suggesting good separation of vanadium (IV) from iron. After five stages of extraction and stripping, highly pure vanadyl sulfate containing 76.5 g/L V (IV) with the impurities of 12 mg/L Fe and 10 mg/L Al was obtained, which is suitable for the electrolyte of a vanadium redox flow battery. Organic solution was well regenerated after stripping by oxalic acid solution to remove the remaining iron. The mechanism of vanadium (IV) extraction using EHEHPA was also discussed based on the Fourier transform infrared spectroscopy (FT-IR) analysis.
Consecutive One-Pot versus Domino Multicomponent Approaches to 3-(Diarylmethylene)oxindoles
Authors: Park Sunhwa , Lee Jiyun , Shin Kye , Oh Euichaul , Seo Jae
Published: March 2017

Based on consecutive one-pot conditions combining three palladium-catalyzed reactions (Sonogashira, Heck and Suzuki-Miyaura reactions), a more efficient domino multicomponent method has been successfully developed to access a wide variety of 3-(diarylmethylene)oxindoles. Microwave irradiation and use of a silver salt were the most important factors to achieve high yields and stereoselectivity.
The Anti-Allergic Rhinitis Effect of Traditional Chinese Medicine of Shenqi by Regulating Mast Cell Degranulation and Th1/Th2 Cytokine Balance
Authors: Shao Yang-Yang , Zhou Yi-Ming , Hu Min , Li Jin-Ze , Chen Cheng-Juan , Wang Yong-Jiang , Shi Xiao-Yun , Wang Wen-Jie , Zhang Tian-Tai
Published: March 2017

Shenqi is a traditional Chinese polyherbal medicine has been widely used for the treatment of allergic rhinitis (AR). The aim of this study was to investigate the anti-allergic rhinitis activity of Shenqi and explore its underlying molecular mechanism. Ovalbumin (OVA)-induced allergic rhinitis rat model was used to evaluate the anti-allergic rhinitis effect of Shenqi. The effect of Shenqi on IgE-mediated degranulation was measured using rat basophilic leukemia (RBL-2H3) cells. Primary spleen lymphocytes were isolated to investigate the anti-allergic mechanism of Shenqi by detecting the expression of transcription factors via Western blot and the level of cytokines (IL-4 and IFN-γ) via ELISA. In OVA-induced AR rat models, Shenqi relieved the allergic rhinitis symptoms, inhibited the histopathological changes of nasal mucosa, and reduced the levels of IL-4 and IgE. The results from the in vitro study certified that Shenqi inhibited mast cell degranulation. Furthermore, the results of GATA3, T-bet, p-STAT6, and SOCS1 expression and production of IFN-γ and IL-4 demonstrated that Shenqi balanced the ratio of Th1/Th2 (IFN-γ/IL-4) in OVA-stimulated spleen lymphocytes. In conclusion, these results suggest that Shenqi exhibits an obvious anti-allergic effect by suppressing the mast cell-mediated allergic response and by improving the imbalance of Th1/Th2 ratio in allergic rhinitis.
Porcine Dendritic Cells as an In Vitro Model to Assess the Immunological Behaviour of Streptococcus suis Subunit Vaccine Formulations and the Polarizing Effect of Adjuvants
Authors: Martelet Léa , Lacouture Sonia , Goyette-Desjardins Guillaume , Beauchamp Guy , Surprenant Charles , Gottschalk Marcelo , Segura Mariela
Published: March 2017

An in vitro porcine bone marrow-derived dendritic cell (DC) culture was developed as a model for evaluating immune polarization induced by adjuvants when administered with immunogens that may become vaccine candidates if appropriately formulated. The swine pathogen Streptococcus suis was chosen as a prototype to evaluate proposed S. suis vaccine candidates in combination with the adjuvants Poly I:C, Quil A ®, Alhydrogel ®, TiterMax Gold ® and Stimune ®. The toll-like receptor ligand Poly I:C and the saponin Quil A ® polarized swine DC cytokines towards a type 1 phenotype, with preferential production of IL-12 and TNF-α. The water-in-oil adjuvants TiterMax Gold ® and Stimune ® favoured a type 2 profile as suggested by a marked IL-6 release. In contrast, Alhydrogel ® induced a type 1/type 2 mixed cytokine profile. The antigen type differently modified the magnitude of the adjuvant effect, but overall polarization was preserved. This is the first comparative report on swine DC immune activation by different adjuvants. Although further swine immunization studies would be required to better characterize the induced responses, the herein proposed in vitro model is a promising approach that helps assessing behaviour of the vaccine formulation rapidly at the pre-screening stage and will certainly reduce numbers of animals used while advancing vaccinology science.
First Results from Sentinel-1A InSAR over Australia: Application to the Perth Basin
Authors: Parker Amy , Filmer Mick , Featherstone Will
Published: March 2017

Past ground-based geodetic measurements in the Perth Basin, Australia, record small-magnitude subsidence (up to 7 mm/y), but are limited to discrete points or traverses across parts of the metropolitan area. Here, we investigate deformation over a much larger region by performing the first application of Sentinel-1A InSAR data to Australia. The duration of the study is short (0.7 y), as dictated by the availability of Sentinel-1A data. Despite this limited observation period, verification of Sentinel-1A with continuous GPS and independent TerraSAR-X provides new insights into the deformation field of the Perth Basin. The displacements recorded by each satellite are in agreement, identifying broad (>5 km wide) areas of subsidence at rates up to 15 mm/y. Subsidence at rates greater than 20 mm/y over smaller regions (∼2 km wide) is coincident with wetland areas, where displacements are temporally correlated with changes in groundwater levels in the unconfined aquifer. Longer InSAR time series are required to determine whether these measured displacements are representative of long-term deformation or (more likely) seasonal variations. However, the agreement between datasets demonstrates the ability of Sentinel-1A to detect small-magnitude deformation over different spatial scales (from 2 km–10 s of km) in the Perth Basin. We suggest that, even over short time periods, these data are useful as a reconnaissance tool to identify regions for subsequent targeted studies, particularly given the large swath size of radar acquisitions, which facilitates analysis of a broader portion of the deformation field than ground-based methods or single scenes of TerraSAR-X.
Evaluation of Satellite Retrievals of Chlorophyll-a in the Arabian Gulf
Authors: Al-Naimi Noora , Raitsos Dionysios , Ben-Hamadou Radhouan , Soliman Yousria
Published: March 2017

The Arabian Gulf is a highly turbid, shallow sedimentary basin whose coastal areas have been classified as optically complex Case II waters (where ocean colour sensors have been proved to be unreliable). Yet, there is no such study assessing the performance and quality of satellite ocean-colour datasets in relation to ground truth data in the Gulf. Here, using a unique set of in situ Chlorophyll-a measurements (Chl-a; an index of phytoplankton biomass), collected from 24 locations in four transects in the central Gulf over six recent research cruises (2015–2016), we evaluated the performance of VIIRS and other merged satellite datasets, for the first time in the region. A highly significant relationship was found (r = 0.795, p < 0.001), though a clear overestimation in satellite-derived Chl-a concentrations is evident. Regardless of this constant overestimation, the remotely sensed Chl-a observations illustrated adequately the seasonal cycles. Due to the optically complex environment, the first optical depth was calculated to be on average 6–10 m depth, and thus the satellite signal is not capturing the deep chlorophyll maximum (DCM at ~25 m). Overall, the ocean colour sensors’ performance was comparable to other Case II waters in other regions, supporting the use of satellite ocean colour in the Gulf. Yet, the development of a regional-tuned algorithm is needed to account for the unique environmental conditions of the Gulf, and ultimately provide a better estimation of surface Chl-a in the region.
Theoretical Study of Monolayer and Double-Layer Waveguide Love Wave Sensors for Achieving High Sensitivity
Authors: Li Shuangming , Wan Ying , Fan Chunhai , Su Yan
Published: March 2017

Love wave sensors have been widely used for sensing applications. In this work, we introduce the theoretical analysis of the monolayer and double-layer waveguide Love wave sensors. The velocity, particle displacement and energy distribution of Love waves were analyzed. Using the variations of the energy repartition, the sensitivity coefficients of Love wave sensors were calculated. To achieve a higher sensitivity coefficient, a thin gold layer was added as the second waveguide on top of the silicon dioxide (SiO2) waveguide–based, 36 degree–rotated, Y-cut, X-propagating lithium tantalate (36° YX LiTaO3) Love wave sensor. The Love wave velocity was significantly reduced by the added gold layer, and the flow of wave energy into the waveguide layer from the substrate was enhanced. By using the double-layer structure, almost a 72-fold enhancement in the sensitivity coefficient was achieved compared to the monolayer structure. Additionally, the thickness of the SiO2 layer was also reduced with the application of the gold layer, resulting in easier device fabrication. This study allows for the possibility of designing and realizing robust Love wave sensors with high sensitivity and a low limit of detection.
Flexible Piezoresistive Sensors Embedded in 3D Printed Tires
Authors: Emon Md , Choi Jae-Won
Published: March 2017

In this article, we report the development of a flexible, 3D printable piezoresistive pressure sensor capable of measuring force and detecting the location of the force. The multilayer sensor comprises of an ionic liquid-based piezoresistive intermediate layer in between carbon nanotube (CNT)-based stretchable electrodes. A sensor containing an array of different sensing units was embedded on the inner liner surface of a 3D printed tire to provide with force information at different points of contact between the tire and road. Four scaled tires, as well as wheels, were 3D printed using a flexible and a rigid material, respectively, which were later assembled with a 3D-printed chassis. Only one tire was equipped with a sensor and the chassis was driven through a motorized linear stage at different speeds and load conditions to evaluate the sensor performance. The sensor was fabricated via molding and screen printing processes using a commercially available 3D-printable photopolymer as 3D printing is our target manufacturing technique to fabricate the entire tire assembly with the sensor. Results show that the proposed sensors, inserted in the 3D printed tire assembly, could detect forces, as well as their locations, properly.
Shadow Detection Based on Regions of Light Sources for Object Extraction in Nighttime Video
Authors: Lee Gil-beom , Lee Myeong-jin , Lee Woo-Kyung , Park Joo-heon , Kim Tae-Hwan
Published: March 2017

Intelligent video surveillance systems detect pre-configured surveillance events through background modeling, foreground and object extraction, object tracking, and event detection. Shadow regions inside video frames sometimes appear as foreground objects, interfere with ensuing processes, and finally degrade the event detection performance of the systems. Conventional studies have mostly used intensity, color, texture, and geometric information to perform shadow detection in daytime video, but these methods lack the capability of removing shadows in nighttime video. In this paper, a novel shadow detection algorithm for nighttime video is proposed; this algorithm partitions each foreground object based on the object’s vertical histogram and screens out shadow objects by validating their orientations heading toward regions of light sources. From the experimental results, it can be seen that the proposed algorithm shows more than 93.8% shadow removal and 89.9% object extraction rates for nighttime video sequences, and the algorithm outperforms conventional shadow removal algorithms designed for daytime videos.
Accurate Determination of the Frequency Response Function of Submerged and Confined Structures by Using PZT-Patches†
Authors: Presas Alexandre , Valentin David , Egusquiza Eduard , Valero Carme , Egusquiza Mònica , Bossio Matias
Published: March 2017

To accurately determine the dynamic response of a structure is of relevant interest in many engineering applications. Particularly, it is of paramount importance to determine the Frequency Response Function (FRF) for structures subjected to dynamic loads in order to avoid resonance and fatigue problems that can drastically reduce their useful life. One challenging case is the experimental determination of the FRF of submerged and confined structures, such as hydraulic turbines, which are greatly affected by dynamic problems as reported in many cases in the past. The utilization of classical and calibrated exciters such as instrumented hammers or shakers to determine the FRF in such structures can be very complex due to the confinement of the structure and because their use can disturb the boundary conditions affecting the experimental results. For such cases, Piezoelectric Patches (PZTs), which are very light, thin and small, could be a very good option. Nevertheless, the main drawback of these exciters is that the calibration as dynamic force transducers (relationship voltage/force) has not been successfully obtained in the past. Therefore, in this paper, a method to accurately determine the FRF of submerged and confined structures by using PZTs is developed and validated. The method consists of experimentally determining some characteristic parameters that define the FRF, with an uncalibrated PZT exciting the structure. These parameters, which have been experimentally determined, are then introduced in a validated numerical model of the tested structure. In this way, the FRF of the structure can be estimated with good accuracy. With respect to previous studies, where only the natural frequencies and mode shapes were considered, this paper discuss and experimentally proves the best excitation characteristic to obtain also the damping ratios and proposes a procedure to fully determine the FRF. The method proposed here has been validated for the structure vibrating in air comparing the FRF experimentally obtained with a calibrated exciter (impact Hammer) and the FRF obtained with the described method. Finally, the same methodology has been applied for the structure submerged and close to a rigid wall, where it is extremely important to not modify the boundary conditions for an accurate determination of the FRF. As experimentally shown in this paper, in such cases, the use of PZTs combined with the proposed methodology gives much more accurate estimations of the FRF than other calibrated exciters typically used for the same purpose. Therefore, the validated methodology proposed in this paper can be used to obtain the FRF of a generic submerged and confined structure, without a previous calibration of the PZT.
Factors Affecting Current and Future CSA Participation
Authors: Vassalos Michael , Gao Zhifeng , Zhang Lisha
Published: March 2017

Community Supported Agriculture (CSA) is one of the widely used direct marketing strategies for small- and midsized farmers. CSA programs are an important option for sustainable production and consumption. It helps growers generate income (improve financial security) and consumers obtain fresh local foods. Sustaining and growing CSA participation is critical in order to continue enjoying these benefits. We used a national online survey in conjunction with discrete choice models to investigate the impact of demographic characteristics, lifestyle preferences, and different information outlets on the probability that a consumer is or will become a CSA member. The results indicate that the factors affecting current and future CSA participation differ substantially. While none of the demographic characteristics has a significant impact on current CSA participation, some of them significantly affect the probability that a consumer will become a CSA member in the future. Lifestyle preferences have a significant impact on current and future CSA participation. Although none of the information outlets examined affect current CSA participation, word-of-mouth and online sources significantly influence the probability that a consumer will join a CSA program in the future. These findings may have important implications for policy makers’ and CSA farm managers’ efforts to sustain future CSA development.
Symmetry in Domination for Hypergraphs with Choice
Authors: S. Berenhaut Kenneth , P. Lidral-Porter Brendan , H. Schoen Theodore , P. Webb Kyle
Published: March 2017

In this paper, we introduce the concept of (pair-wise) domination graphs for hypergraphs endowed with a choice function on edges. We are interested, for instance, in minimal numbers of edges for associated domination graphs. Theorems regarding the existence of balanced (zero-edge) domination graphs are presented. Several open questions are posed.
Pilot Scale Testing of Adsorbent Amended Filters under High Hydraulic Loads for Highway Runoff in Cold Climates
Authors: Monrabal-Martinez Carlos , Ilyas Aamir , Muthanna Tone
Published: March 2017

This paper presents an estimation of the service life of three filters composed of sand and three alternative adsorbents for stormwater treatment according to Norwegian water quality standards for receiving surface waters. The study conducted pilot scale column tests on three adsorbent amended filters for treatment of highway runoff in cold climates under high hydraulic loads. The objectives were to evaluate the effect of high hydraulic loads and the application of deicing salts on the performance of these filters. From previous theoretical and laboratory analysis granulated activated charcoal, pine bark, and granulated olivine were chosen as alternative adsorbent materials for the present test. Adsorption performance of the filters was evaluated vis-à-vis four commonly found hazardous metals (Cu, Pb, Ni and Zn) in stormwater. The results showed that the filters were able to pass water at high inflow rates while achieving high removal. Among the filters, the filters amended with olivine or pine bark provided the best performance both in short and long-term tests. The addition of NaCl (1 g/L) did not show any adverse impact on the desorption of already adsorbed metals, except for Ni removal by the charcoal amended filter, which was negatively impacted by the salt addition. The service life of the filters was found to be limited by zinc and copper, due to high concentrations observed in local urban runoff, combined with moderate affinity with the adsorbents. It was concluded that both the olivine and the pine bark amended filter should be tested in full-scale conditions.
Into Africa: Molecular phylogenetics and historical biogeography of sub‐Saharan African woodferns (Dryopteris)
Authors: Sessa Emily B. , Juslén Aino , Väre Henry , Chambers Sally M.
Published: March 2017

PREMISE OF THE STUDY:

Our goal was to infer the phylogenetic relationships and historical biogeography of the genus Dryopteris with a focus on taxa in sub‐Saharan Africa and neighboring islands. In general, little is known about the relationships between African fern species and their congeners in other geographic regions, and our aim was to determine whether the sub‐Saharan African species of Dryopteris are monophyletic and evolved within Africa or arrived there via repeated dispersals into Africa from other regions.

METHODS:

We obtained sequence data for five chloroplast markers from 214 species of Dryopteris and 18 outgroups. We performed phylogenetic and molecular dating analyses using a Bayesian relaxed clock method in BEAST with fossil and secondary calibration points and estimated ancestral ranges for the genus globally by comparing multiple models in BioGeoBEARS.

KEY RESULTS:

We found that 22 of 27 accessions of sub‐Saharan African Dryopteris belong to a large clade of 31 accessions that also includes taxa from Indian and Atlantic Ocean islands. Additional accessions of taxa from our regions of interest have Asian, Hawaiian, European, or North American species as their closest relatives.

CONCLUSIONS:

The majority of sub‐Saharan African Dryopteris species are descended from a shared common ancestor that dispersed to Africa from Asia approximately 10 Ma. There have been subsequent dispersal events from the African mainland to islands in the Atlantic and Indian Oceans, including Madagascar. Several additional species are estimated to have descended from ancestors that reached Africa via separate events over the last roughly 20 million years.
ON THE ACCURACY OF SOME ABSORBING BOUNDARY CONDITIONS FOR THE SCHRODINGER EQUATION
Authors: Bugajev Andrej , Čiegis Raimondas , Kriauzienė Rima , Leonavičienė Teresė , Žilinskas Julius
Published: March 2017

A detailed analysis of absorbing boundary conditions for the linear Schrodinger equation is presented in this paper. It is focused on absorbing boundary conditions that are obtained by using rational functions to approximate the exact transparent boundary conditions. Different strategies are investigated for the optimal selection of the coefficients of these rational functions, including the Pade approximation, the L2 norm approximations of the Fourier symbol, L2 minimization of a reflection coefficient, and two error minimization techniques for the chosen benchmark problems with known exact solutions. The results of computational experiments are given and a detailed comparison of the efficiency of these techniques is presented.
Mapping the Extinction Curve in 3D: Structure on Kiloparsec Scales
Authors: Schlafly E. F. , Peek J. E. G. , Finkbeiner D. P. , Green G. M.
Published: March 2017

Near-infrared spectroscopy from APOGEE and wide-field optical photometry from Pan-STARRS1 have recently made precise measurements of the shape of the extinction curve possible for tens of thousands of stars, parameterized by R(V). These measurements revealed structures in R(V) with large angular scales, which are challenging to explain in existing dust paradigms. In this work, we combine three-dimensional maps of dust column density with R(V) measurements to constrain the three-dimensional distribution of R(V) in the Milky Way. We find that the variations in R(V) are correlated on kiloparsec scales. In particular, most of the dust within one kiloparsec in the outer Galaxy, including many local molecular clouds (Orion, Taurus, Perseus, California, and Cepheus), has a significantly lower R(V) than more distant dust in the Milky Way. These results provide new input to models of dust evolution and processing, and complicate the application of locally derived extinction curves to more distant regions of the Milky Way and to other galaxies.
Identification of the Hard X-Ray Source Dominating the E > 25 keV Emission of the Nearby Galaxy M31
Authors: Yukita M. , Ptak A. , Hornschemeier A. E. , Wik D. , Maccarone T. J. , Pottschmidt K. , Zezas A. , Antoniou V. , Ballhausen R. , Lehmer B. D. , Lien A. , Williams B. , Baganoff F. , Boyd P. T. , Enoto T. , Kennea J. , Page K. L. , Choi Y.
Published: March 2017

We report the identification of a bright hard X-ray source dominating the M31 bulge above 25 keV from a simultaneous NuSTAR–Swift observation. We find that this source is the counterpart to Swift J0042.6+4112, which was previously detected in the Swift BAT All-sky Hard X-ray Survey. This Swift BAT source had been suggested to be the combined emission from a number of point sources; our new observations have identified a single X-ray source from 0.5 to 50 keV as the counterpart for the first time. In the 0.5–10 keV band, the source had been classified as an X-ray Binary candidate in various Chandra and XMM-Newton studies; however, since it was not clearly associated with Swift J0042.6+4112, the previous E < 10 keV observations did not generate much attention. This source has a spectrum with a soft X-ray excess (kT ∼ 0.2 keV) plus a hard spectrum with a power law of

and a cutoff around 15–20 keV, typical of the spectral characteristics of accreting pulsars. Unfortunately, any potential pulsation was undetected in the NuSTAR data, possibly due to insufficient photon statistics. The existing deep HST images exclude high-mass (>3

) donors at the location of this source. The best interpretation for the nature of this source is an X-ray pulsar with an intermediate-mass (<3

) companion or a symbiotic X-ray binary. We discuss other possibilities in more detail.
The 2014 X-Ray Minimum of η Carinae as Seen by Swift
Authors: Corcoran M. F. , Liburd J. , Morris D. , Russell C. M. P. , Hamaguchi K. , Gull T. R. , Madura T. I. , Teodoro M. , Moffat A. F. J. , Richardson N. D. , Hillier D. J. , Damineli A. , Groh J. H.
Published: March 2017

We report on Swift X-ray Telescope observations of Eta Carinae (η Car), an extremely massive, long-period, highly eccentric binary obtained during the 2014.6 X-ray minimum/periastron passage. These observations show that η Car may have been particularly bright in X-rays going into the X-ray minimum state, while the duration of the 2014 X-ray minimum was intermediate between the extended minima seen in 1998.0 and 2003.5 by Rossi X-Ray Timing Explorer (RXTE), and the shorter minimum in 2009.0. The hardness ratios derived from the Swift observations showed a relatively smooth increase to a peak value occurring 40.5 days after the start of the X-ray minimum, though these observations cannot reliably measure the X-ray hardness during the deepest part of the X-ray minimum when contamination by the “central constant emission” component is significant. By comparing the timings of the RXTE and Swift observations near the X-ray minima, we derive an updated X-ray period of P
X = 2023.7 ± 0.7 days, in good agreement with periods derived from observations at other wavelengths, and we compare the X-ray changes with variations in the He ii 4686 emission. The middle of the “Deep Minimum” interval, as defined by the Swift column density variations, is in good agreement with the time of periastron passage derived from the He ii
λ4686 line variations.
Relativistic Dynamics and Mass Exchange in Binary Black Hole Mini-disks
Authors: Bowen Dennis B. , Campanelli Manuela , Krolik Julian H. , Mewes Vassilios , Noble Scott C.
Published: March 2017

We present the first exploration of gas dynamics in a relativistic binary black hole (BH) system in which an accretion disk (a “mini-disk”) orbits each BH. We focus on 2D hydrodynamical studies of comparable-mass, non-spinning systems. Relativistic effects alter the dynamics of gas in this environment in several ways. Because the gravitational potential between the two BHs becomes shallower than in the Newtonian regime, the mini-disks stretch toward the L1 point and the amount of gas passing back and forth between the mini disks increases sharply with decreasing binary separation. This “sloshing” is quasi-periodically modulated at 2 and 2.75 times the binary orbital frequency, corresponding to timescales of hours to days for supermassive binary black holes (SMBBHs). In addition, relativistic effects add an m = 1 component to the tidally driven spiral waves in the disks that are purely m = 2 in Newtonian gravity; this component becomes dominant when the separation is ≲100 gravitational radii. Both the sloshing and the spiral waves have the potential to create distinctive radiation features that may uniquely mark SMBBHs in the relativistic regime.
The Warm Circumgalactic Medium: 105−6 K Gas Associated with a Single Galaxy Halo or with an Entire Group of Galaxies?
Authors: Stocke John T. , Keeney Brian A. , Danforth Charles W. , Oppenheimer Benjamin D. , Pratt Cameron T. , Berlind Andreas A.
Published: March 2017

In preparation for a Hubble Space Telescope (HST) observing project using the Cosmic Origins Spectrograph (COS), the positions of all AGN targets having high-S/N far-UV G130M spectra were cross-correlated with a large catalog of low-redshift galaxy groups homogenously selected from the spectroscopic sample of the Sloan Digital Sky Survey (SDSS). Searching for targets behind only those groups at z = 0.1–0.2 (which places the O vi doublet in the wavelength region of peak COS sensitivity), we identified only one potential

target, FBQS 1010+3003. An O vi-only absorber was found in its G130M spectrum at z = 0.11326, close to the redshift of a foreground small group of luminous galaxies at z = 0.11685. Because there is no associated Lyα absorption, any characterization of this absorber is necessarily minimal; however, the O vi detection likely traces “warm” gas in collisional ionization equilibrium at T ≈ 3 × 105 K. While this discovery is consistent with being interface gas between cooler, photoionized clouds and a hotter intra-group medium, it could also be warm, interface gas associated with the circumgalactic medium (CGM) of the single closest galaxy. In this case, a detailed analysis of the galaxy distribution (complete to

) strongly favors the individual galaxy association. This analysis highlights the necessity of both high-

COS data and a deep galaxy redshift survey of the region in order to test more rigorously the association of O vi-absorbing gas with a galaxy group. A Cycle 23 HST/COS program is currently targeting 10 UV-bright AGN behind 12 low-redshift galaxy groups to test the warm, group gas hypothesis.
The Role of Cerenkov Radiation in the Pressure Balance of Cool Core Clusters of Galaxies
Authors: Lieu Richard
Published: March 2017

Despite the substantial progress made recently in understanding the role of AGN feedback and associated non-thermal effects, the precise mechanism that prevents the core of some clusters of galaxies from collapsing catastrophically by radiative cooling remains unidentified. In this Letter, we demonstrate that the evolution of a cluster's cooling core, in terms of its density, temperature, and magnetic field strength, inevitably enables the plasma electrons there to quickly become Cerenkov loss dominated, with emission at the radio frequency of ≲350 Hz, and with a rate considerably exceeding free–free continuum and line emission. However, the same does not apply to the plasmas at the cluster's outskirts, which lacks such radiation. Owing to its low frequency, the radiation cannot escape, but because over the relevant scale size of a Cerenkov wavelength the energy of an electron in the gas cannot follow the Boltzmann distribution to the requisite precision to ensure reabsorption always occurs faster than stimulated emission, the emitting gas cools before it reheats. This leaves behind the radiation itself, trapped by the overlying reflective plasma, yet providing enough pressure to maintain quasi-hydrostatic equilibrium. The mass condensation then happens by Rayleigh–Taylor instability, at a rate determined by the outermost radius where Cerenkov radiation can occur. In this way, it is possible to estimate the rate at ≈2 M
⊙ year−1, consistent with observational inference. Thus, the process appears to provide a natural solution to the longstanding problem of “cooling flow” in clusters; at least it offers another line of defense against cooling and collapse should gas heating by AGN feedback be inadequate in some clusters.