bluuebunny/crossref_metadata_2025 huggingface dataset:
Composite Replacement of Amalgam Restoration Versus Freshly Cut Dentin: An In Vitro Microleakage Comparison
Authors: Redwan H , Bardwell DN , Ali A , Finkelman M , Khayat S , Weber H-P
Published: February 2016

Objective: The aim of this study was to evaluate the microleakage of the composite restorations when bonded to tooth structure previously restored with amalgam material compared with that of freshly cut dentin.

Methods and Materials: Thirty intact, extracted intact human molars were mounted in autopolymerizing acrylic resin. Class II box preparations were prepared on the occluso-proximal surfaces of each tooth (4-mm bucco-lingual width and 2-mm mesio-distal depth) with the gingival cavosurface margin 1 mm above the CEJ. Each cavity was then restored using high copper amalgam restoration (Disperalloy, Dentsply) and then thermocycled for 10,000 thermal cycles. Twenty-five of the amalgam restorations were then carefully removed and replaced with Filtek Supreme Ultra Universal (3M ESPE); the remaining five were used for scanning electron microscopy and energy dispersive x-ray spectroscopy analysis. A preparation of the same dimensions was performed on the opposite surface of the tooth and restored with composite resin and thermocycled for 5000 thermal cycles. Twenty samples were randomly selected for dye penetration testing using silver nitrate staining to detect the microleakage. The specimens were analyzed with a stereomicroscope at a magnification of 20×. All of the measurements were done in micrometers; two readings were taken for each cavity at the occlusal and proximal margins. Two measurements were taken using a 0-3 scale and the percentage measurements.

Results: Corrosion products were not detected in either group (fresh cut dentin and teeth previously restored with amalgam). No statistically significant difference was found between the microleakage of the two groups using a 0-3 scale at the occlusal margins (McNemar test, p=0.727) or proximal margins (Wilcoxon signed-rank test, p=0.174). No significance difference was found between the two groups using the percentage measurements and a Wilcoxon signed-rank test at either the occlusal (p=0.675) or proximal (p=0.513) margins. However, marginal microleakage was statistically significant between the proximal and occlusal margins (p<0.001).

Conclusion: Within the limitations of this in vitro study, no significant difference was found between the microleakage of nondiscolored dentin in teeth that were previously restored with amalgam compared with freshly cut dentin. However, marginal microleakage in the proximal surface was higher than that in the occlusal surface.
From ‘Direct Versus Indirect' Toward an Integrated Restorative Concept in the Posterior Dentition
Authors: Opdam NJM , Frankenberger R , Magne P
Published: February 2016

Traditionally, indirect restorations are expected to have better longevity than direct restorations. The introduction of adhesive dentistry and the minimally invasive approach of restorative treatment has changed this. In this article, the differences in longevity between direct and indirect restorations in the posterior dentition are explained. In addition, the advantages and disadvantages of direct and indirect restorations placed in a minimally invasive way and using a proper adhesive technique are described.
Fracture Load and Phase Transformation of Monolithic Zirconia Crowns Submitted to Different Aging Protocols
Authors: Bergamo ETP , da Silva WJ , Cesar PF , Del Bel Cury AA
Published: February 2016

Monolithic zirconia crowns have many favorable properties and may potentially be used to solve dental problems such as chipping. However, monolithic zirconia crown resistance can be affected by its phase transformation when subjected to low temperatures, humidity, and stress. This study evaluated the fracture load and phase transformation of monolithic zirconia crowns submitted to different thermal and mechanical aging tests. Seventy monolithic zirconia crowns were randomly divided into the following five groups: control, no treatment; hydrothermal aging at 122°C, two bar for one hour; thermal fatigue, 104 cycles between 5°C and 55°C, dwell time, 30 seconds; and mechanical fatigue, 106 cycles with a load of 70 N, sliding of 1.5 mm at 1.4 Hz; and combination of mechanical plus thermal fatigue. Fracture load was measured with a universal testing machine. Surface changes and fracture mode and origin were examined with a scanning electron microscope. Monoclinic phase content was evaluated by x-ray diffraction. The fracture load was analyzed using one-way analysis of variance at a level of 5%, and Weibull distribution was performed. No statistically significant differences were observed in the mean fracture load and characteristic fracture load among the groups (p>0.05). The Weibull modulus ranged from 6.2 to 16.6. The failure mode was similar for all groups with the crack origin located at the contact point of the indenter. Phase transformation was shown at different surfaces of the crown in all groups (1.9% to 8.9%). In conclusion, monolithic zirconia crowns possess high fracture load, structural reliability, and low phase transformation.
Intraoral Repair of Direct and Indirect Restorations: Procedures and Guidelines
Authors: Loomans BAC , Özcan M
Published: February 2016

The service life of defective direct or indirect restorations could be prolonged by repair or relayering actions where durable adhesion of resin-based composite materials is established for longevity of repairs. The advances in adhesive technologies have introduced several surface conditioning concepts to adhere resin composites onto different restorative materials. The purpose of this report is to summarize reasons for failure, survival of repaired reconstructions, elaborate upon types and mechanisms of available surface conditioning methods, and present operative dentists with practical guidelines for intraoral repair procedures.
Morphological characteristics of subchondral bone cysts in medial femoral condyles of adult horses as determined by computed tomography
Authors: Walker Wade T. , Silverberg Jesse L. , Kawcak Christopher E. , Nelson Bradley B. , Fortier Lisa A.
Published: February 2016

OBJECTIVE To determine morphological characteristics of subchondral bone cysts (SBCs) in medial femoral condyles (MFCs) of adult horses with orthopedic disease.

SAMPLE CT scans of 7 MFCs with SBCs from 6 adult horses.

PROCEDURES CT was used to determine the volume, surface area, and centers of the articular cyst opening and SBC in each MFC. Cysts were ordered from smallest to largest on the basis of volume. Osseous pathological characteristics of the MFC were assessed in the frontal plane. Three-dimensional distance of displacement between the center of the articular cyst opening and center of the cyst was determined for each SBC. Cyst surface area-to-volume ratio was evaluated and compared with that of a true sphere.

RESULTS All SBCs had a defect in the subchondral bone plate at the cranial 15% to 20% of the MFC. Cyst center was located in a caudal, proximal, and abaxial direction with respect to the center of the articular cyst opening for each horse. Small- and intermediate-volume SBCs were irregular and multilobulated, whereas large-volume SBCs were smooth and discrete with a surface area-to-volume ratio approaching that of a sphere.

CONCLUSIONS AND CLINICAL RELEVANCE Consistency in morphological characteristics suggested a common etiopathogenesis for SBCs in MFCs of adult horses. Cyst enlargement may have been attributable to a biomechanical predisposition to decrease the surface area-to-volume ratio, resulting in a spherical cyst.
Inpatient Rehabilitation Outcomes in Patients With Stroke Aged 85 Years or Older
Authors: O'Brien Suzanne R. , Xue Ying
Published: February 2016

Background

In the United States, people 85 years of age or older have a growing number of strokes each year, and this age group is most at risk for disability. Inpatient rehabilitation facilities (IRFs) adhere closest to post-acute stroke rehabilitation guidelines and have the most desirable outcomes compared with skilled nursing facilities. As stroke is one of the leading causes of disability, knowledge of postrehabilitation outcomes is needed for this age group, although at present such information is limited.

Objective

The purpose of this study was to describe functional and discharge outcomes after IRF rehabilitation in people with stroke aged 85 years or older.

Design

A serial, cross-sectional design was used.

Methods

Inpatient Rehabilitation Facility–Patient Assessment Instrument data were analyzed beginning in 2002 for the first 5.5 years after implementation of the prospective payment system and included 71,652 cases. Discharge function, measured using the Functional Independence Measure (FIM), and community discharge were the discharge outcome measures. Sample description used frequencies and means. Generalized estimating equations (GEEs) with post hoc testing were used to analyze the annual trends for discharge FIM and community discharge by age group (85–89, 90–94, 95–99, and ≥100 years). Risk-adjusted linear and logistic GEE models, with control for cluster, were used to analyze the association between both outcome measures and age group.

Results

Over 5.5 years, mean discharge FIM scores decreased by 3.6 points, and mean achievement of community discharge decreased 5.5%. Approximately 54% of the sample achieved community discharge. Continuous and logistic GEEs revealed factors associated with discharge outcomes.

Limitations

Results obtained using an observational design should not be viewed as indicating causation. The lack of control for a caregiver may have altered results.

Conclusions

The very elderly people admitted to IRF stroke rehabilitation made functional gains, and most were able to return to the community.
Influence of calcination temperature on sol–gel synthesized single-phase bismuth titanate for high dielectric capacitor applications
Authors: Thiruramanathan Pandirengan , Marikani Arumugam , Madhavan Durairaj , Bharadwaj Suresh , Awasthi Anand Mohan
Published: February 2016

An inexpensive sol–gel combustion method using citric acid as fuel has been used to synthesize bismuth titanate, Bi4Ti3O12 nanopowders. Thermogravimetric analysis proved that a calcination temperature of 900 °C is sufficient for the preparation of single-phase bismuth titanate. X-ray diffraction and Fourier transform infrared spectroscopy are used to examine the influence of calcination temperature on the structural growth of the Bi4Ti3O12 nanopowder. The average crystallite size estimated by using the Scherrer method and the Williamson–Hall method was found to increase with calcination temperature. Photoluminescence behavior as a function of calcination temperature was observed at two different excitation wavelengths of 300 nm and 420 nm. The morphology of the particles analyzed using images obtained from field emission scanning electron microscopy displayed irregular, random sized, and spherical-shaped structures. The stoichiometry and purity of the nanopowder are confirmed by energy-dispersive spectroscopy. The broadband dielectric results established the highest dielectric constant (∊r = 450) for a frequency of 100 Hz achieved with a potential capacitance of 138 pF m−2. This establishes Bi4Ti3O12 as a promising dielectric material for achieving high energy density capacitors for the next-generation passive devices.
Fracture Analysis of High Strength Steel Fastener Used in Separation System of a Satellite Launch Vehicle
Authors: Manwatkar Sushant K. , Murty S.V.S. Narayana , Narayanan P. Ramesh
Published: February 2016

High strength 3.5Ni-1.5Cr-0.5Mo (AFNOR 35NCD16) steel fasteners are widely used for various space applications. In one such application, failure was observed in one of the M4X8L fasteners used in the band clip assembly of a separation system. The band assembly was preloaded to the specified value of load as per the assembly procedure and the fastener was torqued to the specified value of 2.3Nm with loctite. The fastener was found to be separated into two pieces at head-shank junction under assembly load conditions. Detailed analysis of the cracked fastener indicated the failure to be due to the hydrogen induced stress corrosion cracking (HI-SCC). This paper presents the details of the failure of the fastener.
Separation of Church from State? Secular Somatechnologies of Governmentality and Pedagogy
Authors: Laforteza Elaine
Published: February 2016

This paper examines how two secular nation-states, such as Australia and the Philippines, connect through their shared practice of secularism as Christianity. Through this, the paper argues that secularism in these contexts enables a Christian framework in which ‘mainstreaming’ Muslims becomes a paramount technique in fostering bilateral relations and (trans)national security. In focus is the Basic Education Assistance for Mindanao project, which Australia and the Philippines have established as a pedagogical tool for including Muslim-Filipinos within ‘secular’ society.
Direct Numerical Simulation of Turbulent Channel Flow on High-Performance GPU Computing System
Authors: Alfonsi Giancarlo , Ciliberti Stefania , Mancini Marco , Primavera Leonardo
Published: February 2016

The flow of a viscous fluid in a plane channel is simulated numerically following the DNS approach, and using a computational code for the numerical integration of the Navier-Stokes equations implemented on a hybrid CPU/GPU computing architecture (for the meaning of symbols and acronyms used, one can refer to the Nomenclature). Three turbulent-flow databases, each representing the turbulent statistically-steady state of the flow at three different values of the Reynolds number, are built up, and a number of statistical moments of the fluctuating velocity field are computed. For turbulent-flow-structure investigation, the vortex-detection technique of the imaginary part of the complex eigenvalue pair in the velocity-gradient tensor is applied to the fluctuating-velocity fields. As a result, and among other types, hairpin vortical structures are unveiled. The processes of evolution that characterize the hairpin vortices in the near-wall region of the turbulent channel are investigated, in particular at one of the three Reynolds numbers tested, with specific attention given to the relationship that exists between the dynamics of the vortical structures and the occurrence of ejection and sweep quadrant events. Interestingly, it is found that the latter events play a preminent role in the way in which the morphological evolution of a hairpin vortex develops over time, as related in particular to the establishment of symmetric and persistent hairpins. The present results have been obtained from a database that incorporates genuine DNS solutions of the Navier-Stokes equations, without superposition of any synthetic structures in the form of initial and/or boundary conditions for the simulations.
Self-Organization with Constraints—A Mathematical Model for Functional Differentiation
Authors: Tsuda Ichiro , Yamaguti Yutaka , Watanabe Hiroshi
Published: February 2016

This study proposes mathematical models for functional differentiations that are viewed as self-organization with external constraints. From the viewpoint of system development, the present study investigates how system components emerge under the presence of constraints that act on a whole system. Cell differentiation in embryos and functional differentiation in cortical modules are typical examples of this phenomenon. In this paper, as case studies, we deal with three mathematical models that yielded components via such global constraints: the genesis of neuronal elements, the genesis of functional modules, and the genesis of neuronal interactions. The overall development of a system may follow a certain variational principle.
Comments on Meo et al. Association of Exposure to Radio-Frequency Electromagnetic Field Radiation (RF-EMFR) Generated by Mobile Phone Base Stations with Glycated Hemoglobin (HbA1c) and Risk of Type 2 Diabetes Mellitus. Int. J. Environ. Res. Public Health, 2015, 12, 14519–14528
Authors: Mortazavi Seyed , Mortazavi Ghazal , Mortazavi Seyed
Published: February 2016

With great interest and enthusiasm, we have read the article by Meo et al. entitled “Association of Exposure to Radio-Frequency Electromagnetic Field Radiation (RF-EMFR) Generated by Mobile Phone Base Stations with Glycated Hemoglobin (HbA1c) and Risk of Type 2 Diabetes Mellitus” that is published in the latest issue of the International Journal of Environmental Research and Public Health [1].[...]
Erythropoietin Ameliorates Neonatal Hypoxia-Ischemia-Induced Neurobehavioral Deficits, Neuroinflammation, and Hippocampal Injury in the Juvenile Rat
Authors: Lan Kuo-Mao , Tien Lu-Tai , Cai Zhengwei , Lin Shuying , Pang Yi , Tanaka Sachiko , Rhodes Philip , Bhatt Abhay , Savich Renate , Fan Lir-Wan
Published: February 2016

The hematopoietic growth factor erythropoietin (EPO) has been shown to be neuroprotective against hypoxia-ischemia (HI) in Postnatal Day 7 (P7)–P10 or adult animal models. The current study was aimed to determine whether EPO also provides long-lasting neuroprotection against HI in P5 rats, which is relevant to immature human infants. Sprague-Dawley rats at P5 were subjected to right common carotid artery ligation followed by an exposure to 6% oxygen with balanced nitrogen for 1.5 h. Human recombinant EPO (rEPO, at a dose of 5 units/g) was administered intraperitoneally one hour before or immediately after insult, followed by additional injections at 24 and 48 h post-insult. The control rats were injected with normal saline following HI. Neurobehavioral tests were performed on P8 and P20, and brain injury was examined on P21. HI insult significantly impaired neurobehavioral performance including sensorimotor, locomotor activity and cognitive ability on the P8 and P20 rats. HI insult also resulted in brain inflammation (as indicated by microglia activation) and neuronal death (as indicated by Jade B positive staining) in the white matter, striatum, cortex, and hippocampal areas of the P21 rat. Both pre- and post-treatment with rEPO significantly improved neurobehavioral performance and protected against the HI-induced neuronal death, microglia activation (OX42+) as well as loss of mature oligodendrocytes (APC-CC1+) and hippocampal neurons (Nissl+). The long-lasting protective effects of rEPO in the neonatal rat HI model suggest that to exert neurotrophic activity in the brain might be an effective approach for therapeutic treatment of neonatal brain injury induced by hypoxia-ischemia.
Silicon-Doped Titanium Dioxide Nanotubes Promoted Bone Formation on Titanium Implants
Authors: Zhao Xijiang , Wang Tao , Qian Shi , Liu Xuanyong , Sun Junying , Li Bin
Published: February 2016

While titanium (Ti) implants have been extensively used in orthopaedic and dental applications, the intrinsic bioinertness of untreated Ti surface usually results in insufficient osseointegration irrespective of the excellent biocompatibility and mechanical properties of it. In this study, we prepared surface modified Ti substrates in which silicon (Si) was doped into the titanium dioxide (TiO2) nanotubes on Ti surface using plasma immersion ion implantation (PIII) technology. Compared to TiO2 nanotubes and Ti alone, Si-doped TiO2 nanotubes significantly enhanced the expression of genes related to osteogenic differentiation, including Col-I, ALP, Runx2, OCN, and OPN, in mouse pre-osteoblastic MC3T3-E1 cells and deposition of mineral matrix. In vivo, the pull-out mechanical tests after two weeks of implantation in rat femur showed that Si-doped TiO2 nanotubes improved implant fixation strength by 18% and 54% compared to TiO2-NT and Ti implants, respectively. Together, findings from this study indicate that Si-doped TiO2 nanotubes promoted the osteogenic differentiation of osteoblastic cells and improved bone-Ti integration. Therefore, they may have considerable potential for the bioactive surface modification of Ti implants.
Immunohistochemical Analysis of Cerebral Thrombi Retrieved by Mechanical Thrombectomy from Patients with Acute Ischemic Stroke
Authors: Schuhmann Michael , Gunreben Ignaz , Kleinschnitz Christoph , Kraft Peter
Published: February 2016

Mechanical thrombectomy is a novel treatment option for patients with acute ischemic stroke (AIS). Only a few studies have previously suggested strategies to categorize retrieved clots according to their histologic composition. However, these reports did not analyze potential biomarkers that are of importance in stroke-related inflammation. We therefore histopathologically investigated 37 intracerebral thrombi mechanically retrieved from patients with AIS, and focused on the composition of immune cells and platelets. We also conducted correlation analyses of distinctive morphologic patterns (erythrocytic, serpentine, layered, red, white, mixed appearance) with clinical parameters. Most T cells and monocytes were detected in erythrocytic and red clots, in which the distribution of these cells was random. In contrast, von Willebrand factor (vWF)-positive areas co-localized with regions of fibrin and collagen. While clots with huge amounts of vWF seem to be associated with a high National Institute of Health Stroke Scale score at admission, histologic findings could not predict the clinical outcome at discharge. In summary, we provide the first histologic description of mechanically retrieved intracerebral thrombi regarding biomarkers relevant for inflammation in ischemic stroke.
Reinforcing Low-Volume Fraction Nano-TiN Particulates to Monolithical, Pure Mg for Enhanced Tensile and Compressive Response
Authors: Meenashisundaram Ganesh , Nai Mui , Almajid Abdulhakim , Gupta Manoj
Published: February 2016

Novel Mg (0.58, 0.97, 1.98 and 2.5) vol. % TiN nanocomposites containing titanium nitride (TiN) nanoparticulates of ~20 nm size are successfully synthesized by a disintegrated melt deposition technique followed by hot extrusion. Microstructural characterization of Mg-TiN nanocomposites indicate significant grain refinement with Mg 2.5 vol. % TiN exhibiting a minimum grain size of ~11 μm. X-ray diffraction studies of Mg-TiN nanocomposites indicate that addition of up to 1.98 vol. % TiN nanoparticulates aids in modifying the strong basal texture of pure Mg. An attempt is made to study the effects of the type of titanium (metal or ceramic), size, and volume fraction addition of nanoparticulates on the microstructural and mechanical properties of pure magnesium. Among the major strengthening mechanisms contributing to the strength of Mg-Ti-based nanocomposites, Hall-Petch strengthening was found to play a vital role. The synthesized Mg-TiN nanocomposites exhibited superior tensile and compression properties indicating significant improvement in the fracture strain values of pure magnesium under loading. Under tensile and compression loading the presence of titanium (metal or ductile phase) nanoparticulates were found to contribute more towards the strengthening, whereas ceramics of titanium (brittle phases) contribute more towards the ductility of pure magnesium.
Development of Hybrid Surfaces with Tunable Wettability by Selective Surface Modifications
Authors: Lee Hyun-Joong , Park Keun
Published: February 2016

Recent advances in micro/nano technology have driven artificial modifications of surface wettability by mimicking biological surfaces, such as superhydrophobic and water-harvesting surfaces. In this study, surface wettability of polycarbonate (PC) films was modified using various surface treatments: micropatterning using ultrasonic imprint lithography, fluorinate silane coating, and electron beam irradiation. To modify surface wettability selectively in a specified region, these three treatments were performed using profiled masks with the corresponding shapes. Various combinations of these treatments were investigated in terms of wettability changes, by measuring contact angle (CA). The semi-hydrophobic PC film (CA: 89.2°) was modified to create a super- hydrophobic state (CA: 155.9°) by virtue of the selective micropatterning and coating. The electron beam irradiation had an opposite effect, reducing the CA (48.2°), so that the irradiated region was modified to create a hydrophilic state. Two combinations of the proposed surface modifications made it possible to have a great difference in CA on a single surface (107.7°), and to have four different wetting states on a single surface. Various water-drop experiments proved that the developed hybrid surfaces were selectively wettable and showed water-collecting capability.
Rheological, Morphological and Mechanical Studies of Sustainably Sourced Polymer Blends Based on Poly(Lactic Acid) and Polyamide 11
Authors: Walha Fatma , Lamnawar Khalid , Maazouz Abderrahim , Jaziri Mohamed
Published: February 2016

The objective of this study was to gain a deep understanding of composition and compatibilization effects on the properties of entirely sustainably sourced polymer blends based on polylactide (PLA) and polyamide 11 (PA11). Generally, PLA cannot challenge regular commodity polymers due to its weak thermo-mechanical properties and its poor elongation properties. With this work, however, we present a promising route to overcome these drawbacks in order to enhance the processability of PLA: blending the polymer with various compositions of other ductile biopolymers such as PA11, as well as mixing PLA/PA11 blends with various amounts of a chain extender, Joncryl ADR®-4368, containing reactive epoxy functions, in a laboratory-scale twin-screw extruder. The effects on the rheological, morphological and mechanical properties were investigated. Results showed that a “self compatibilization” between PLA and PA11 chains can occur but it was found to be insufficient, contrary to recent work reported in the literature. The role of Joncryl as a compatibilizer for the PLA/PA11 system has been demonstrated by the significant decrease of particle size and interfacial tension as well as the improvement of ductile properties. Moreover, a new relaxation peak appeared in the relaxation spectrum, indicating the generation of a copolymer at the polymer-polymer interface.
Polydopamine Particle as a Particulate Emulsifier
Authors: Nishizawa Nobuaki , Kawamura Ayaka , Kohri Michinari , Nakamura Yoshinobu , Fujii Syuji
Published: February 2016

“Pickering-type” emulsions were prepared using polydopamine (PDA) particles as a particulate emulsifier and n-dodecane, methyl myristate, toluene or dichloromethane as an oil phase. All the emulsions prepared were oil-in-water type and an increase of PDA particle concentration decreased oil droplet diameter. The PDA particles adsorbed to oil–water interface can be crosslinked using poly(ethylene imine) as a crosslinker, and the PDA particle-based colloidosomes were successfully fabricated. Scanning electron microscopy studies of the colloidosomes after removal of inner oil phase revealed a capsule morphology, which is strong evidence for the attachment of PDA particles at the oil–water interface thereby stabilizing the emulsion. The colloidosomes after removal of inner oil phase could retain their capsule morphology, even after sonication. On the other hand, the residues obtained after oil phase removal from the PDA particle-stabilized emulsion prepared in the absence of any crosslinker were broken into small fragments of PDA particle flocs after sonication.
A River Basin over the Course of Time: Multi-Temporal Analyses of Land Surface Dynamics in the Yellow River Basin (China) Based on Medium Resolution Remote Sensing Data
Authors: Wohlfart Christian , Liu Gaohuan , Huang Chong , Kuenzer Claudia
Published: February 2016

The Yellow River Basin is one of China’s most densely-populated, fastest growing and most dynamic regions, with abundant natural resources and intense agricultural production. Major land policies have recently resulted in remarkable landscape modifications throughout the basin. The availability of precise regional land cover change information is crucial to better understand the prevailing dynamics and underlying factors influencing the current processes in such a complex system and can additionally serve as a valuable component for modeling and decision making. Such comprehensive and detailed information is lacking for the Yellow River Basin so far. In this study, we derived land cover characteristics and dynamics from the complete last decade based on optical high-temporal MODIS Normalized Differenced Vegetation Index (NDVI) time series for the whole Yellow River Basin. After filtering and smoothing for noise reduction with the use of the adaptive Savitzky–Golay filter, the processed time series was used to derive a large variety of phenological and annual metrics. The final classifications for the basin (2003 and 2013) were based on a random forest classifier, trained by reference samples from very high-resolution imagery. The accuracy assessment for all 18 thematic classes, which was based on a 30% reference data split, yielded an overall accuracy of 87% and 84% for 2003 and 2013, respectively. Major land cover and land use changes during the last decade have occurred on the Loess Plateau, where land and conservation reforms triggered large-scale recovery of grassland and shrubland habitat that had been previously covered by agriculture or sparse vegetation. Agricultural encroachment and urban area expansion are other processes influencing the dynamics in the basin. The necessity for regionally-adapted land cover maps becomes obvious when our land cover products are compared to existing global products, where thematic accuracy remains low, particularly in a heterogeneous landscape, such as the Yellow River Basin. The basin-wide novel land cover and land use products of the Yellow River Basin hold a large potential for climate, hydrology and biodiversity modelers, as well as river basin and regional governmental authorities and will be shared upon request.
ℓ0-Norm Sparse Hyperspectral Unmixing Using Arctan Smoothing
Authors: Esmaeili Salehani Yaser , Gazor Saeed , Kim Il-Min , Yousefi Shahram
Published: February 2016

The goal of sparse linear hyperspectral unmixing is to determine a scanty subset of spectral signatures of materials contained in each mixed pixel and to estimate their fractional abundances. This turns into an ℓ0 -norm minimization, which is an NP-hard problem. In this paper, we propose a new iterative method, which starts as an ℓ1 -norm optimization that is convex, has a unique solution, converges quickly and iteratively tends to be an ℓ0 -norm problem. More specifically, we employ the arctan function with the parameter σ ≥ 0 in our optimization. This function is Lipschitz continuous and approximates ℓ1 -norm and ℓ0 -norm for small and large values of σ, respectively. We prove that the set of local optima of our problem is continuous versus σ. Thus, by a gradual increase of σ in each iteration, we may avoid being trapped in a suboptimal solution. We propose to use the alternating direction method of multipliers (ADMM) for our minimization problem iteratively while increasing σ exponentially. Our evaluations reveal the superiorities and shortcomings of the proposed method compared to several state-of-the-art methods. We consider such evaluations in different experiments over both synthetic and real hyperspectral data, and the results of our proposed methods reveal the sparsest estimated abundances compared to other competitive algorithms for the subimage of AVIRIS cuprite data.
Using Remotely Sensed Imagery to Document How Land Use Drives Turbidity of Playa Waters in Texas
Authors: Starr Scott , Heintzman Lucas , Mulligan Kevin , Barbato Lucia , McIntyre Nancy
Published: February 2016

Sedimentation (primarily from human land use) is a major threat to runoff-fed wetlands of the Great Plains of North America (playas), but it is unknown how many playas are turbid, how prevalence of turbidity has changed over time, and how turbidity is related to surrounding land use. We used remotely sensed imagery to assess sedimentation in the waters of over 7700 playa basins in Texas on four dates during a 29-year span: 25 July 1986 (a regionally wet time), 3 May 2014 (during drought), 4 June 2014 (after the drought was broken), and 25 July 2015 (one year post-drought). Even on the wettest date examined, 64% of playa basins did not hold water. Turbidity varied over time, was already present in over half of the basins examined in 1986, and prevalence of turbidity was not simply proportional to overall wet playa abundance. There was an increase in total and irrigated cropland in our focal region and a statistically significant association between sedimentation and land use within 100 m of a playa: clear playas were associated with more urban development and pasture/grassland, and turbid playas were surrounded mostly by cropland.
Metal Sulfides as Sensing Materials for Chemoresistive Gas Sensors
Authors: Gaiardo Andrea , Fabbri Barbara , Guidi Vincenzo , Bellutti Pierluigi , Giberti Alessio , Gherardi Sandro , Vanzetti Lia , Malagù Cesare , Zonta Giulia
Published: February 2016

This work aims at a broad overview of the results obtained with metal-sulfide materials in the field of chemoresistive gas sensing. Indeed, despite the well-known electrical, optical, structural and morphological features previously described in the literature, metal sulfides present lack of investigation for gas sensing applications, a field in which the metal oxides still maintain a leading role owing to their high sensitivity, low cost, small dimensions and simple integration, in spite of the wide assortment of sensing materials. However, despite their great advantages, metal oxides have shown significant drawbacks, which have led to the search for new materials for gas sensing devices. In this work, Cadmium Sulfide and Tin (IV) Sulfide were investigated as functional materials for thick-film chemoresistive gas-sensors fabrication and they were tested both in thermo- and in photo-activation modes. Furthermore, electrical characterization was carried out in order to verify their gas sensing properties and material stability, by comparing the results obtained with metal sulfides to those obtained by using their metal-oxides counterparts. The results highlighted the possibility to use metal sulfides as a novel class of sensing materials, owing to their selectivity to specific compounds, stability, and the possibility to operate at room temperature.
The Additional Error of Inertial Sensors Induced by Hypersonic Flight Conditions
Authors: Karachun Volodimir , Mel’nick Viktorij , Korobiichuk Igor , Nowicki Michał , Szewczyk Roman , Kobzar Svitlana
Published: February 2016

The emergence of hypersonic technology pose a new challenge for inertial navigation sensors, widely used in aerospace industry. The main problems are: extremely high temperatures, vibration of the fuselage, penetrating acoustic radiation and shock N-waves. The nature of the additional errors of the gyroscopic inertial sensor with hydrostatic suspension components under operating conditions generated by forced precession of the movable part of the suspension due to diffraction phenomena in acoustic fields is explained. The cause of the disturbing moments in the form of the Coriolis inertia forces during the transition of the suspension surface into the category of impedance is revealed. The boundaries of occurrence of the features on the resonance wave match are described. The values of the “false” angular velocity as a result of the elastic-stress state of suspension in the acoustic fields are determined.
Where’s Wally? In Search of Citizen Perspectives on the Smart City
Authors: Thomas Vanessa , Wang Ding , Mullagh Louise , Dunn Nick
Published: February 2016

This paper builds upon an earlier conference publication by the authors, offering contributions based on a systematic literature review and qualitative study. The paper begins by drawing attention to the paucity of “citizen”—more appropriately, “situated”—perspectives on what a smart city should and could be. The paper then addresses that absence by detailing a research project that explored how people in London, Manchester, and Glasgow responded to the smart city concept. Participants were asked questions regarding their prior familiarity with the phrase “smart city”, their thoughts relating to what it means for a city to be smart, and what a “true” smart city might mean to them. The paper analyses and offers a synthesis of the responses collected throughout the research with the dominant rhetoric about smart cities, as identified through a recent systematic literature review, thereby providing a critical assessment of the values underlying the smart city. It aims to explore and present some of the expectations that citizens hold for their cities’ politicians, policy makers, planners, academics, and technology companies. We believe that these perspectives from citizens can be used to inform responsible development, spatially and socially inclusive technologies, and ultimately more resilient cities.
Comparative Life Cycle Assessment (LCA) of Two On-Site Small-Scale Activated Sludge Total Oxidation Systems in Plastic and Vibrated Reinforced Concrete
Authors: De Feo Giovanni , Ferrara Carmen , Iuliano Giovanni
Published: February 2016

This study proposes a comparison of the environmental impacts calculated with the Life Cycle Assessment (LCA) methodology of two on-site small-scale activated sludge total oxidation systems in linear low-density polyethylene (LLDPE) and vibrated reinforced concrete (VRC). The plants were designed to ensure a treatment capacity of 5, 10, 20 and 30 equivalent inhabitants (PE). The main aim of the study was to evaluate the incidence of construction, disposal and operation phases on the total impacts evaluated with three different methods: ReCiPe 2008, Ecological Footprint and IPCC 2007 100 years. The most significant phase for both treatment lines was the use phase, which contributed more than 80% to the total impacts. The construction phase was the second most impactful phase with an incidence less than 25% for both systems and for all the considered impacts assessment methods. The plant in LLDPE was more eco-friendly than that in (VRC). The plant in VRC was always most impactful, even comparing each single phase of the life cycle and for all the treatment capacities taken into consideration. Finally, the obtained results were not dependent on the impact assessment method considered.
Spatial and Temporal Variations of Streambed Vertical Hydraulic Conductivity in the Weihe River, China
Authors: Wang Liping , Song Jinxi , Zhang Bo , Guo Hongtao , Jiang Weiwei , Wen Ming , Zhang Guotao
Published: February 2016

This study demonstrates the spatial and temporal variations of streambed vertical hydraulic conductivity Kv from October 2011 to November 2014 along the Weihe River, the largest tributary of the Yellow River. The streambed Kv values of a total number of 385 locations from five test sites were estimated on the basis of in situ falling-head standpipe permeameter tests. The difference of Kv values for all test locations reaches five orders of magnitude with a range from 5.87E-04 to 61.3 m/d and a median value of 1.62E-01 m/d. The streambed Kv values are neither normally nor log-normally distributed, but display significant spatial variability among the five test sites. The highest Kv values occur at the site with mainly sandy sediment, while the Kv values at the other four sites with mainly silt-clay sediment are relatively close and have less variability than those at the sandy sediment site. The median Kv values from all of the sites exhibit no statistically significant temporal trends. However, the median Kv values indeed show temporal variations that might be influenced by changes in silt-clay content of the sediment, especially for the sandy sediment site and the combined data from all sites. Weak evidence demonstrates that streambed Kv values decrease with depth.
THE INFLUENCE OF ACCRETION RATE AND METALLICITY ON THERMONUCLEAR BURSTS: PREDICTIONS FROM KEPLER MODELS
Authors: Lampe Nathanael , Heger Alexander , Galloway Duncan K.
Published: February 2016

Using the KEPLER hydrodynamics code, 464 models of thermonuclear X-ray bursters were performed across a range of accretion rates and compositions. We present the library of simulated burst profiles from this sample, and examine variations in the simulated light curve for different model conditions. We find that the recurrence time varies as a power law against accretion rate, and measure its slope while mixed H/He burning is occurring for a range of metallicities, finding the power law gradient to vary from

to 1.24. We identify the accretion rates at which mixed H/He burning stops and a transition occurs to different burning regimes. We explore how varying the accretion rate and metallicity affects burst morphology in both the rise and tail.
RESOLVING GAS FLOWS IN THE ULTRALUMINOUS STARBURST IRAS 23365+3604 WITH KECK LGSAO/OSIRIS*
Authors: Martin Crystal L. , Soto Kurt T.
Published: February 2016

Keck OSIRIS/LGSAO observations of the ultraluminous galaxy IRAS 23365+3604 resolve a circumnuclear bar (or irregular disk) of semimajor axis 0.″42 (520 pc) in Paα emission. The line-of-sight velocity of the ionized gas increases from the northeast toward the southwest; this gradient is perpendicular to the photometric major axis of the infrared emission. Two pairs of bends in the zero-velocity line are detected. The inner bend provides evidence for gas inflow onto the circumnuclear disk/bar structure. We interpret the gas kinematics on kiloparsec scales in relation to the molecular gas disk and multiphase outflow discovered previously. In particular, the fast component of the ouflow (detected previously in line wings) is not detected, adding support to the conjecture that the fast wind originates well beyond the nucleus. These data directly show the dynamics of gas inflow and outflow in the central kiloparsec of a late-stage, gas-rich merger and demonstrate the potential of integral field spectroscopy to improve our understanding of the role of gas flows during the growth phase of bulges and supermassive black holes.
SPATIAL-DEPENDENT PROPAGATION OF COSMIC RAYS RESULTS IN SPECTRUM OF PROTON, RATIOS OF
, B/C AND ANISOTROPY OF NUCLEI
Authors: Guo Yi-Qing , Tian Zhen , Jin Chao
Published: February 2016

Recent precise measurements of cosmic ray spectra revealed an anomalous hardening at ∼200 GV, observed by the ATIC, CREAM, PAMELA, and AMS02 experiments. Particularly, the latest observation of the

ratio by AMS02 demonstrated a flat distribution, which further validated the spectral anomalies of secondary particles. All those new phenomena indicated that the conventional propagation model of cosmic rays meets a challenge. In this work, the spatial-dependent diffusion coefficient

is employed by tracing the source distribution under the physical picture of the two-halo model in the DRAGON package. Under such a scenario, the model calculation will result in two-component spectra for primary nuclei. Due to the smaller rigidity dependence of

in the galactic disk, the ratios secondary-to-primary will inevitably be flatter and the expected anisotropy of cosmic rays will be much more attenuated than in the conventional model. As a result, we can reproduce the spectral hardening of protons, the flat ratios of

and B/C, and consistent anisotropy from ∼100 GeV to ∼100 TeV by only adopting one set of spatial-dependent diffusion coefficients

in a galactic disk.
CLASSICAL Oe STARS IN THE FIELD OF THE SMALL MAGELLANIC CLOUD*
Authors: Golden-Marx Jesse B. , Oey M. S. , Lamb J. B. , Graus Andrew S. , White Aaron S.
Published: February 2016

We present 29 ± 1 classical Oe stars from RIOTS4 (the Runaways and Isolated O Type Star Spectroscopic Survey of the SMC), a spatially complete, spectroscopic survey of Small Magellanic Cloud (SMC) field OB stars. The two earliest are O6e stars, and four are earlier than any Milky Way (MW) Oe stars. We also find ten Ope stars, showing He i infill and/or emission; five appear to be at least as hot as ∼O7.5e stars. The hottest, star 77616, shows He ii disk emission, suggesting that even the hottest O stars can form decretion disks, and offers observational support for theoretical predictions that the hottest, fastest rotators can generate He+-ionizing atmospheres. Our data also demonstrate that Ope stars correspond to Oe stars earlier than O7.5e with strong disk emission. We find that in the SMC, Oe stars extend to earlier spectral types than in the MW, and our SMC Oe/O frequency, 0.26 ± 0.04, is much greater than the MW value, 0.03 ± 0.01. These results are consistent with angular momentum transport by stronger winds suppressing decretion disk formation at higher metallicity. In addition, the Oe star frequency in the SMC field is indistinguishable from that for clusters, which is consistent with the similarity between rotation rates in these environments, and contrary to the pattern for MW rotation rates. Thus, our findings strongly support the viscous decretion disk model and confirm that Oe stars are the high-mass extension of the Be phenomenon. Additionally, we find that Fe ii emission occurs among Oe stars later than O7.5e with massive disks, and we revise a photometric criterion for identifying Oe stars to

.
Factores determinantes en la producción científica de los grupos de investigación en Colombia
Authors: Rueda-Barrios Gladys , Rodenes-Adam Manuel
Published: February 2016

Existe un gran debate sobre la forma como deben estar organizadas las instituciones creadoras de conocimiento, es el caso de las universidades, grupos y centros de investigación; así como, los procesos claves de gestión del conocimiento que deben aplicar los grupos de investigación; y los recursos financieros, humanos y tecnológicos necesarios para lograr un alto rendimiento en la investigación. El presente trabajo pretende, a partir de la revisión teórica y el estudio empírico, determinar la relación entre los resultados de producción científica obtenidos por los grupos de investigación adscritos a universidades en Colombia, respecto a las variables cultura organizacional, gestión del conocimiento y capital tecnológico. Para el análisis, se obtuvo una muestra de 223 grupos de investigación a nivel nacional, y que se encuentran registrados y categorizados por el Departamento Administrativo Nacional de Ciencia, Tecnología e Innovación en Colombia (Colciencias, 2010). Los datos analizados se obtuvieron a partir de la aplicación de una encuesta que permitía medir la percepción de los líderes investigadores sobre las variables independientes cultura de la universidad, procesos de gestión de conocimiento y capital tecnológico; y la variable dependiente, producción científica, se analizó a partir de la calificación que asigna Colciencias a cada grupo por los resultados de investigación obtenidos durante un periodo de tiempo. Las técnicas estadísticas utilizadas en este estudio son: el análisis de regresión y el análisis de ecuaciones estructurales, con los cuales se determinó que la cultura motivadora, el proceso de externalización en la gestión del conocimiento y el capital tecnológico influyen de forma positiva en los resultados obtenidos en producción científica.