bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of signal detection SNR limits in snapshot-deficient scenarios with colored noise
Authors: Diaz-Santos Jose A. , Wage Kathleen E.
Published: May 2015

Most source enumeration algorithms assume a white noise background; however, in many underwater applications, the background noise is colored. Various researchers have investigated the problem of source enumeration when the background noise is colored. The standard approach is to apply a whitening filter before the signal enumeration algorithm. Most of these algorithms perform poorly when the number of noise snapshots used to estimate the whitening filter is small. Nadakuditi and Silverstein [IEEE J. Sel. Topics Signal Process., 2010] developed an algorithm for source enumeration using random matrix theory that provides the fundamental SNR limits for snapshot-deficient scenarios with arbitrary noise. Nadakuditi and Silverstein's analysis focuses on the performance when the number of signal plus noise snapshots varies while the number of snapshots used for the whitening filter stays constant. This talk analyzes the performance of this algorithm when number of snapshots available to estimate the whitening filter varies from N to 10 N. Simulations using two different colored noise models for a large vertical linear array located in the deep ocean will be presented.
Effect of reverberation on instrumental vibrato tones
Authors: Smith Sarah R. , Bocko Mark F.
Published: May 2015

Musical vibrato is the process by which a performer subtly varies the frequency and amplitude of a note for expressive effect. Previous work has suggested that the vibrato modulation may not be uniform across all overtones, causing the individual frequency trajectories to become decorrelated. In this study, we investigate the effect of reverberation on instrumental tones performed with vibrato. This is accomplished by performing a detailed time-frequency analysis to extract the instantaneous frequencies of many overtones. In order to accurately track the low amplitudes of the upper harmonics, we present an algorithm tailored for optimal tracking in as little as 10 dB SNR. For tones recorded in an anechoic environment, the instantaneous frequency modulations of all the overtones are found to be highly correlated. However, tones recorded in a reverberant space, as well as anechoic recordings processed with a synthetic reverberation are found to have significantly lower correlations between the overtones. In addition to providing insight into musical timbre variations, these results could be useful for characterization of acoustic transfer functions or applications where overtone correlation is assumed, such as audio source separation.
Striation processing of continuously active sonar data
Authors: Schecklman Scott , Zurk Lisa M.
Published: May 2015

Previous work by the authors has shown that striations associated with the waveguide invariant can provide a new physics-based tracking constraint that improves tracking performance in pulsed active sonar data. A necessary pre-processing step is to isolate the target return from the direct arrival and other target echoes. Striation-based beamforming can be used as an optional pre-processing step to preserve the multipath structure in the beamformer output of a horizontal line array. Recent interest in continuously active sonar (CAS) processing has motivated research to determine how striations might be similarly exploited for tracking when the sonar is operated with a high duty cycle. In CAS signals, the direct arrival is almost always overlapping in time with the target echo return and the standard time-gating technique cannot isolate the echo return. In this paper, a time-dependent filter is introduced to isolate and extract the CAS echo spectrum. The conditions in which striation-based beamforming should be applied to preserve the striation structure in the beam output are also explored. The physics-based signal processing algorithms discussed here are expected to provide valuable information about the target’s multipath structure, which can be exploited in an extended Kalman filter for enhanced tracker performance.
Efficient estimation of the probability density function of transmission loss in uncertain ocean environments
Authors: Patterson Brandon , Dowling David R.
Published: May 2015

Predictions of acoustic transmission loss (TL) in the ocean are useful in a variety of naval and ocean engineering applications. However, real ocean environments are imperfectly known and have many uncertainties. Consequently, TL calculations performed for these environments are also uncertain. Traditional Monte-Carlo methods used to obtain probability density functions (PDF) of TL in such circumstances require many field calculations, and are impractical for real-time applications. This presentation describes how the PDF of TL at a point of interest may be estimated using a single TL-field calculation and the statistics of TL within a range-depth area containing that point. To document the performance of this technique, RAM was used to perform TL field calculations for 100 Hz and 300 Hz sound sources in realistic ocean sound channels with eight uncertain environmental parameters describing the bathymetry, sound speed profile, and bottom properties. Preliminary results indicate that TL PDFs generated with area statistics have an L1-error ≤ 0.5 when compared with 1000-calculation Monte-Carlo PDF results throughout most of the sound channel. However, greater errors were observed in the near field as well as in areas where the sound channel depth was less than 100 m, for 100 Hz sound. [Sponsored by ONR.]
Metal electrode direct sound generation in seawater
Authors: McBeth Michael S.
Published: May 2015

Thermoacoustic expansion of water due to Ohmic heating and volume changes in the very thin Helmholtz double layer that forms adjacent to metal electrodes are two mechanisms that have been used to explain sound generation by metal electrodes in seawater. Using 20 gauge solid sterling silver wire electrodes with only the circular cross section of the wire exposed, our experiments have demonstrated intense sound production in the form of acoustic tone bursts in seawater from a thermoacoustic mechanism at a second harmonic of 20 kHz of the electrical driving frequency at 10 kHz. Additionally, we observed a separate intense and transient acoustic tone burst generation from a mechanism we attribute to vesicle layer excitation where the vesicle is a highly charged layer of water associated with the boundary of droplets and bubbles. This vesicle layer excitation sound generation mechanism is distinct from any Helmholtz double layer mechanism since the double layer is always present while the acoustic tone burst we observe repeatedly occurs after about 4.4 ms of applied alternating voltage at 10 kHz and last only about 560 μs. We present our experimental setup and results. Moving seawater directly to generate sound may lead to more compact projectors.
The Internal and External Responses to a Forward-Specific Rugby League Simulation Protocol Performed With and Without Physical Contact
Authors: Mullen Thomas , Highton Jamie , Twist Craig
Published: May 2015

It is important to understand the extent to which physical contact changes the internal and external load during rugby simulations that aim to replicate the demands of match play. Accordingly, this study examined the role of physical contact on the physiological and perceptual demands during and immediately after a simulated rugby league match. Nineteen male rugby players completed a contact (CON) and a noncontact (NCON) version of the rugby league match-simulation protocol in a randomized crossover design with 1 wk between trials. Relative distance covered (ES = 1.27; ±0.29), low-intensity activity (ES = 1.13; ±0.31), high-intensity running (ES = 0.49; ±0.34), heart rate (ES = 0.52; ±0.35), blood lactate concentration (ES = 0.78; ±0.34), rating of perceived exertion (RPE) (ES = 0.72; ±0.38), and session RPE (ES = 1.45; ±0.51) were all higher in the CON than in the NCON trial. However, peak speeds were lower in the CON trial (ES = −0.99; ±0.40) despite unclear reductions in knee-extensor (ES = 0.19; ±0.40) and -flexor (ES = 0.07; ±0.43) torque. Muscle soreness was also greater after CON than in the NCON trial (ES = 0.97; ±0.55). The addition of physical contact to the movement demands of a simulated rugby league match increases many of the external and internal demands but also results in players’ slowing their peak running speed during sprints. These findings highlight the importance of including contacts in simulation protocols and training practices designed to replicate the demands of real match play.
Enhancing Change-of-Direction Speed in Soccer Players by Functional Inertial Eccentric Overload and Vibration Training
Authors: Tous-Fajardo Julio , Gonzalo-Skok Oliver , Arjol-Serrano José Luis , Tesch Per
Published: May 2015

Purpose:

To examine the effects of a novel isoinertial eccentric-overload and vibration training (EVT) paradigm on change-ofdirection (COD) speed and multiple performance tests applicable to soccer.

Methods:

Twenty-four young male players were assigned to an EVT (n = 12) or conventional combined (CONV, n = 12) group, once weekly for 11 wk. EVT consisted of 2 sets of 6–10 repetitions in 5 specific and 3 complementary exercises. CONV used comparable volume (2 sets of 6–10 reps in 3 sequences of 3 exercises) of conventional combined weight, plyometric, and linear speed exercises. Pre- and postintervention tests included 25-m sprint with 4 × 45° COD every 5th m (V-cut test), 10- and 30-m sprints, repeat-sprint ability, countermovement jump, and hopping (RJ5).

Results:

Group comparison showed very likely to likely better performance for EVT in the COD (effect size [ES] = 1.42), 30-m (ES = 0.98), 10-m (ES = 1.17), and average power (ES = 0.69) and jump height (ES = 0.69) during RJ5. There was a large (r = –.55) relationship between the increase in average hopping power and the reduced V-cut time.

Conclusions:

As EVT, not CONV, improved not only COD ability but also linear speed and reactive jumping, this “proof-of-principle” study suggests that this novel exercise paradigm performed once weekly could serve as a viable adjunct to improve performance tasks specific to soccer.
Effects of Static and Dynamic Stretching on Injury Prevention in High School Soccer Athletes: A Randomized Trial
Authors: Zakaria Alan A. , Kiningham Robert B. , Sen Ananda
Published: May 2015

Objective:

To determine if there is any benefit to static stretching after performing a dynamic warm-up in the prevention of injury in high school soccer athletes.

Design:

Prospective cluster randomized nonblinded study.

Setting:

12 high schools with varsity and junior varsity boys’ soccer teams (24 soccer teams) across the state of Michigan.

Participants:

Four hundred ninety-nine student-athletes were enrolled, and 465 completed the study. One high school dropped out of the study in the first week, leaving a total of 22 teams.

Interventions:

Dynamic stretching protocol vs dynamic + static (D+S) stretching protocol.

Main Outcome Measures:

Lower-extremity, core, or lower-back injuries per team.

Results:

Twelve teams performed the dynamic stretching protocol and 10 teams performed the D+S stretching protocol. There were 17 injuries (1.42 ± 1.49 injuries/team) among the teams that performed the dynamic stretching protocol and 20 injuries (2.0 ± 1.24 injuries/team) among the teams that performed the D+S protocol. There was no statistically significant difference in injuries between the 2 groups (P = .33).

Conclusions:

There is no difference between dynamic stretching and D+S stretching in the prevention of lower-extremity, core, and back injuries in high school male soccer athletes. Static stretching does not provide any added benefit to dynamic stretching in the prevention of injury in this population before exercise.
Reversible centriole depletion with an inhibitor of Polo-like kinase 4
Authors: Wong Yao Liang , Anzola John V. , Davis Robert L. , Yoon Michelle , Motamedi Amir , Kroll Ashley , Seo Chanmee P. , Hsia Judy E. , Kim Sun K. , Mitchell Jennifer W. , Mitchell Brian J. , Desai Arshad , Gahman Timothy C. , Shiau Andrew K. , Oegema Karen
Published: May 2015

Giving an old organelle the old heave-ho

Centrioles are ancient cellular organelles that build centrosomes, the major microtubule-organizing centers in animal cells. Duplication of centrioles is tightly controlled to ensure that each dividing cell has precisely two centrosomes. Human cancer cells often have extra centrosomes, which has been hypothesized to confer a proliferative advantage. Wong
et al.
developed small molecules (centrinones) that allowed them to reversibly “delete” centrioles from cells (see the Perspective by Stearns). Surprisingly, cancer cells continued to divide in the absence of centrosomes, whereas normal cells stopped dividing.

Science
, this issue p.
1155
; see also p.
1091
It's about time for neural crest
Authors: Hoppler Stefan , Wheeler Grant N.
Published: May 2015

The unusual pluripotency of neural crest cells is inherited from embryonic stem cells

[Also see Research Article by

Buitrago-Delgado
et al.

]
Genome Sequences of Three Strains of Lactobacillus paracasei of Different Origins and with Different Cholate Sensitivities
Authors: Shiwa Yuh , Atarashi Hotaka , Tanaka Naoto , Okada Sanae , Yoshikawa Hirofumi , Endo Akihito , Miyaji Tatsuro , Nakagawa Junichi
Published: May 2015

We report here the draft genome sequences of three strains of
Lactobacillus paracasei
(NRIC 0644, NRIC 1781, and NRIC 1917) isolated from different sources. The three genomes range from 2.95 to 3.15 Mb with a G+C content of 46% and contain approximately 2,700 protein coding sequences.
Metagenome Sequencing of a Coastal Marine Microbial Community from Monterey Bay, California
Authors: Mueller Ryan S. , Bryson Sam , Kieft Brandon , Li Zhou , Pett-Ridge Jennifer , Chavez Francisco , Hettich Robert L. , Pan Chongle , Mayali Xavier
Published: May 2015

Heterotrophic microbes are critical components of aquatic food webs. Linkages between populations and the substrates they utilize are not well defined. We present the metagenome of microbial communities from the coastal Pacific Ocean exposed to various nutrient additions in order to better understand substrate utilization and partitioning in this environment.
Ten‐minute chat
Authors: Smith Martin
Published: May 2015

Martin Smith is veterinary team manager for BPEX, which represents pig levy payers in England.
Field performance of in-service cast iron water reticulation pipe buried in reactive clay
Authors: Chan Derek , Gallage Chaminda Pathma Kumara , Rajeev Pathmanathan , Kodikara Jayantha
Published: May 2015

Field monitoring is an important means for understanding soil behaviour and its interaction with buried structures such as pipeline. This paper details the successful instrumentation of a section of an in-service cast iron water main buried in an area of reactive clay where frequent water pipe breakage has been observed. The instrumentation included measurement of pipe strain; pipe water pressure and temperature; soil pressure, temperature, moisture content, and matric suction; as well as the meteorological conditions on site. The data generally indicated that changes in soil temperature, suction, and moisture content were directly related to the local climatic variations. The suction and moisture content data indicated that the soil profile at the site down to around 700 mm, and probably down to 1000 mm, is affected by changes in surface weather, while soil conditions below this depth appear to be more stable. Analysis of pipe strain indicated that the pipe behaves like a cantilever beam, with the top experiencing predominantly tensile strains during summer. Subsequently, these trends reduce to compressive strains as soil swelling occurs because of the increase of moisture content with the onset of winter.
Functionalization of germanene by metal atoms adsorption: A first-principles study
Authors: Pang Qing , Li Long , Zhang Lin-li , Zhang Chun-ling , Song Yu-ling
Published: May 2015

First-principles calculations were performed to study the adsorption characteristics of 15 different metal atoms on germanene. For the alkali metal adatoms (Li, Na, and K) on germanene, the bonding is approximately ideal ionic and the semimetallic germanene finally becomes metallic with a small band gap opening at the Dirac point. The bonding of alkaline earth metal atoms (Be, Mg, and Ca) to germanene is a mixture of ionic and covalent. The Be and Mg adsorptions lead to semiconducting behavior in germanene, while similar to Li, Na, and K adsorptions, the Ca adsorbed germanene is metallic. For most transition metal adatoms, a strong covalent bonding behavior is found between the adatom and germanene layer, which causes much larger distortions in the germanene lattice. As a result of partially occupied d orbital, the transition metals show also diverse electronic structures when interacting with germanene, such as nonmagnetic metal, nonmagnetic semiconductor, ferromagnetic metal, ferromagnetic semiconductor, and more particularly, ferromagnetic half-metal. In addition, the analysis of the partial density of states indicates that the ferromagnetic property of the obtained transition metal – germanene systems mainly results from the spin-split of the adatom 3d states. The rich electronic and magnetic properties of metal–germanene systems may have potential applications for designing new nanoscale electronic and spintronic devices.
Controlling Dynamics of Hidden Attractors
Authors: Sharma Pooja Rani , Shrimali Manish Dev , Prasad Awadhesh , Kuznetsov N. V. , Leonov G. A.
Published: May 2015

Amplitude death (AD) in hidden attractors is attained with a scheme of linear augmentation. This linear control scheme is capable of stabilizing the system to a fixed point state even when the original system does not have any fixed point. Depending on the control parameter, different routes to AD such as boundary crises and Hopf bifurcation are observed. Lyapunov exponent and amplitude index are used to study the dynamical properties of the system.
Miocene tectonic evolution of the basins and fault systems, SE Korea: dextral, simple shear during the East Sea (Sea of Japan) opening
Authors: Son M. , Song C. W. , Kim M.-C. , Cheon Y. , Cho H. , Sohn Y. K.
Published: May 2015

Crustal deformation of SE Korea caused by back-arc opening of the East Sea (Sea of Japan) commenced locally in the Late Oligocene. Intense deformation occurred during the Early Miocene, accompanying extension of parallelogram-shaped pull-apart basins between NNW-striking principal displacement zones, clockwise rotation and northwestward tilting of blocks, and southwestward propagating rifting. At about 17 Ma, the crustal deformation suddenly expanded westward and northward owing to activation of the Yeonil Tectonic Line, resulting in a dramatic change of depositional environment and the subsidence of wedge-shaped pull-apart basins. The Yeonil Tectonic Line and western border faults of the Pohang Basin are the westernmost limit of the Miocene crustal deformation. All the features of crustal deformation in SE Korea support the pull-apart model for the East Sea opening. However, they indicate that the NNW-striking faults such as the Yeonil Tectonic Line acted as the principal displacement zones rather than the NNE-striking Yangsan Fault under a consistent dextral simple shear. At about 16 Ma, the collision of the Philippine Sea Plate with the Japanese Islands caused a tectonic inversion. This inversion resulted in a compositional change of basaltic magma at about 15 Ma and crustal uplift in SE Korea, which caused the cessation of sedimentation at about 10 Ma.
Zircon provenance of SW Caledonian phyllites reveals a distant Timanian sediment source
Authors: Slama Jiri , Pedersen Rolf B.
Published: May 2015

Cambrian to middle Ordovician schists and phyllites in southwestern Baltica, now exposed in the (par-)autochthon to Lower Allochthon nappes of the Scandinavian Caledonides in southern Norway, contain previously unrecognized far-travelled detrital zircons with ages in the intervals 0.47–0.8 and 1.85–3.2 Ga and ε
Hf
in the range −27 to +18. These ages are assigned to Timanian and Fennoscandian Shield sources respectively and contrast with the locally derived detritus with zircon ages of
c
. 0.9–1.8 Ga and ε
Hf
values
c
. −13 to +10. The far-travelled zircons provide evidence that a steady, long-haul, source-to-sink drainage system existed from the northeastern fringe of Baltica to the SW passive margin across the whole palaeocontinent (
c
. 2000 km) since
c
. 521 Ma, and that the Timanian orogen shed detritus across large distances towards both its foreland (Baltica) and hinterland (Arctica). There are several arguments against an Avalonian source for these zircons. Recycling of the detrital zircon from the Cambrian to middle Ordovician sediments is probably responsible for the presence of Cryogenian to Middle Ordovician zircon ages in younger sedimentary sequences of southwestern Baltica. The development of an ophiolitic mélange associated with Ordovician phyllites underlying the Jotun Nappe Complex seems to mark the change to an active continental margin in the middle Ordovician, heralding the Caledonian orogeny. The study demonstrates that detrital zircon-poor fine-grained (siltstone to mudstone) sediments are an extremely valuable indicator for distal sources and favourably complement zircon-rich coarser sandstone in provenance analysis.

Supplementary material:

Results of LA-ICP-MS and SIMS U–Pb–Hf analyses of zircons with details of analytical methods and the collection of CL images of the youngest (<500 Ma) detrital zircon grains are available at
http://www.geolsoc.org.uk/SUP18827
.
Energy Modeling of Software for a Hardware Multithreaded Embedded Microprocessor
Authors: Kerrison Steve , Eder Kerstin
Published: May 2015

This article examines a hardware multithreaded microprocessor and discusses the impact such an architecture has on existing software energy modeling techniques. A framework is constructed for analyzing the energy behavior of the XMOS XS1-L multithreaded processor and a variation on existing software energy models is proposed, based on analysis of collected energy data. It is shown that by combining execution statistics with sufficient data on the processor’s thread activity and instruction execution costs, a multithreaded software energy model used with Instruction Set Simulation can yield an average error margin of less than 7%.
Computing Education in Korea—Current Issues and Endeavors
Authors: Choi Jeongwon , An Sangjin , Lee Youngjun
Published: May 2015

Computer education has been provided for a long period of time in Korea. Starting as a vocational program, the content of computer education for students evolved to include content on computer literacy, Information Communication Technology (ICT) literacy, and brand-new computer science. While a new curriculum related to computer science was established in 2007, the range of computer education being provided in Korean schools has been repeatedly reduced. To identify the cause of this recent phenomenon, we review the computer education environment using the Darmstadt model, including educational systems, curricula, and teaching environments. Then we examine what factors affected the decline of computer education. The major causes of failure are found to be the absence of policy and a comprehensive evaluation method. These causes have led to a reduction in the selection ratio of computer-related subjects and in the number of students taking computer classes. Based on this understanding, we bring some fundamental message for establishing robust computer science education.
A Probabilistic Calculus for Probabilistic Real-Time Systems
Authors: Santinelli Luca , Cucu-Grosjean Liliana
Published: May 2015

Challenges within real-time research are mostly in terms of modeling and analyzing the complexity of actual real-time embedded systems. Probabilities are effective in both modeling and analyzing embedded systems by increasing the amount of information for the description of elements composing the system. Elements are tasks and applications that need resources, schedulers that execute tasks, and resource provisioning that satisfies the resource demand. In this work, we present a model that considers component-based real-time systems with component interfaces able to abstract both the functional and nonfunctional requirements of components and the system. Our model faces probabilities and probabilistic real-time systems unifying in the same framework probabilistic scheduling techniques and compositional guarantees varying from soft to hard real time. We provide an algebra to work with the probabilistic notation developed and form an analysis in terms of sufficient probabilistic schedulability conditions for task systems with either preemptive fixed-priority or earliest deadline first scheduling paradigms.
Virtual Platform-Based Design Space Exploration of Power-Efficient Distributed Embedded Applications
Authors: Sayyah Parinaz , Lazarescu Mihai T. , Bocchio Sara , Ebeid Emad , Palermo Gianluca , Quaglia Davide , Rosti Alberto , Lavagno Luciano
Published: May 2015

Networked embedded systems are essential building blocks of a broad variety of distributed applications ranging from agriculture to industrial automation to healthcare and more. These often require specific energy optimizations to increase the battery lifetime or to operate using energy harvested from the environment. Since a dominant portion of power consumption is determined and managed by software, the software development process must have access to the sophisticated power management mechanisms provided by state-of-the-art hardware platforms to achieve the best tradeoff between system availability and reactivity. Furthermore, internode communications must be considered to properly assess the energy consumption.

This article describes a design flow based on a SystemC virtual platform including both accurate power models of the hardware components and a fast abstract model of the wireless network. The platform allows both model-driven design of the application and the exploration of power and network management alternatives. These can be evaluated in different network scenarios, allowing one to exploit power optimization strategies without requiring expensive field trials. The effectiveness of the approach is demonstrated via experiments on a wireless body area network application.
Authentic Assessment Tasks: Students take a deep approach to learning
Authors: Adapa Sujana
Published: May 2015

This article presents the student-centered, deep approach to learning. The teaching resources developed for two strategic and services marketing courses have been integrated with several formative and summative assessment tasks. Authentic assessment tasks allowed for deeper engagement of students with the subject content, peers, and the course coordinator. A student-centered deeper approach to learning is evident through the creative thinking and problem solving demonstrated through the provision of solutions to real-life business problems.
More Than Pretty: A review of Visual Design Solutions
Authors: Tracey Ryan
Published: May 2015

Whether you realize it or not, you are a visual designer. But do not fear, because Connie Malamed's latest book will help you make your pictures more than pretty, by making them effective.
A Tale of Amalgamation of Three Permo-Triassic Collage Systems in Central Asia: Oroclines, Sutures, and Terminal Accretion
Authors: Xiao Wenjiao , Windley Brian F. , Sun Shu , Li Jiliang , Huang Baochun , Han Chunming , Yuan Chao , Sun Min , Chen Hanlin
Published: May 2015

The Central Asian Orogenic Belt records the accretion and convergence of three collage systems that were finally rotated into two major oroclines. The Mongolia collage system was a long, N–S-oriented composite ribbon that was rotated to its current orientation when the Mongol-Okhotsk orocline was formed. The components of the Kazakhstan collage system were welded together into a long, single composite arc that was bent to form the Kazakhstan orocline. The cratons of Tarim and North China were united and sutured by the Beishan orogen, which terminated with formation of the Solonker suture in northern China. All components of the three collage systems were generated by the Neoproterozoic and were amalgamated in the Permo-Triassic. The Central Asian Orogenic Belt evolved by multiple convergence and accretion of many orogenic components during multiple phases of amalgamation, followed by two phases of orocline rotation.
Advances in Skeletal Dysplasia Genetics
Authors: Geister Krista A. , Camper Sally A.
Published: May 2015

Skeletal dysplasias result from disruptions in normal skeletal growth and development and are a major contributor to severe short stature. They occur in approximately 1/5,000 births, and some are lethal. Since the most recent publication of the Nosology and Classification of Genetic Skeletal Disorders, genetic causes of 56 skeletal disorders have been uncovered. This remarkable rate of discovery is largely due to the expanded use of high-throughput genomic technologies. In this review, we discuss these recent discoveries and our understanding of the molecular mechanisms behind these skeletal dysplasia phenotypes. We also cover potential therapies, unusual genetic mechanisms, and novel skeletal syndromes both with and without known genetic causes. The acceleration of skeletal dysplasia genetics is truly spectacular, and these advances hold great promise for diagnostics, risk prediction, and therapeutic design.
Parity and Time-Reversal Violation in Atomic Systems
Authors: Roberts B.M. , Dzuba V.A. , Flambaum V.V.
Published: May 2015

Studying the violation of parity and time-reversal invariance in atomic systems has proven to be a very effective means of testing the electroweak theory at low energy and searching for physics beyond it. Recent developments in both atomic theory and experimental methods have led to the ability to make extremely precise theoretical calculations and experimental measurements of these effects. Such studies are complementary to direct high-energy searches, and can be performed for only a fraction of the cost. We review the recent progress in the field of parity and time-reversal violation in atoms, molecules, and nuclei, and examine the implications for physics beyond the Standard Model, with an emphasis on possible areas for development in the near future.
Playing on a Pathogen's Weakness: Using Evolution to Guide Sustainable Plant Disease Control Strategies
Authors: Zhan Jiasui , Thrall Peter H. , Papaïx Julien , Xie Lianhui , Burdon Jeremy J.
Published: May 2015

Wild plants and their associated pathogens are involved in ongoing interactions over millennia that have been modified by coevolutionary processes to limit the spatial extent and temporal duration of disease epidemics. These interactions are disrupted by modern agricultural practices and social activities, such as intensified monoculture using superior varieties and international trading of agricultural commodities. These activities, when supplemented with high resource inputs and the broad application of agrochemicals, create conditions uniquely conducive to widespread plant disease epidemics and rapid pathogen evolution. To be effective and durable, sustainable disease management requires a significant shift in emphasis to overtly include ecoevolutionary principles in the design of adaptive management programs aimed at minimizing the evolutionary potential of plant pathogens by reducing their genetic variation, stabilizing their evolutionary dynamics, and preventing dissemination of pathogen variants carrying new infectivity or resistance to agrochemicals.
STEM Education
Authors: Xie Yu , Fang Michael , Shauman Kimberlee
Published: May 2015

Improving science, technology, engineering, and mathematics (STEM) education, especially for traditionally disadvantaged groups, is widely recognized as pivotal to the United States's long-term economic growth and security. In this article, we review and discuss current research on STEM education in the United States, drawing on recent research in sociology and related fields. The reviewed literature shows that different social factors affect the two major components of STEM education attainment: (a) attainment of education in general, and (b) attainment of STEM education relative to non-STEM education conditional on educational attainment. Cognitive and social-psychological characteristics matter for both components, as do structural influences at the family, neighborhood, school, and broader cultural levels. However, whereas commonly used measures of socioeconomic status (SES) predict the attainment of general education, social-psychological factors are more important influences on participation and achievement in STEM versus non-STEM education. Domestically, disparities by family SES, race, and gender persist in STEM education. Internationally, American students lag behind those in some countries with fewer economic resources. Explanations for group disparities within the United States and the mediocre international ranking of US student performance require more research, a task that is best accomplished through interdisciplinary approaches.
Vanadium Oxide Polycrystalline Nanorods and Ion-Exchanged Nanotubes for Enhanced Lithium Intercalation
Authors: McNulty David , Buckley D. Noel , O'Dwyer Colm
Published: May 2015

In this work we investigate two alternative methods to remove amine molecules from as-synthesized vanadium oxide nanotubes (VONTs). Thermal treatment results in the formation of polycrystalline nanorods (poly-NRs) and ion exchange reactions with NaCl result in the formation of Na-VONTs. The removal of amine molecules is confirmed by monitoring the inorganic and organic phase changes and decomposition, respectively, using electron microscopy, IR spectroscopy and X-ray diffraction analyses. We compare the electrochemical performance of as-synthesized VONTs, poly-NRs and Na-VONTs. This work demonstrates that the presence of amine molecules within the layers of vanadium oxide impedes the intercalation of lithium ions, and that their removal results in a significant improvement in electrochemical characteristics. Out of the three vanadium oxide nanostructures investigated, poly- NRs exhibit the most promising results for practical use as a cathode material.
Influence of Convective Drying Parameters on Electrode Performance and Physical Electrode Properties
Authors: Westphal Bastian , Bockholt Henrike , Günther T , Haselrieder W , Kwade Arno
Published: May 2015

In the present work two of the various drying process parameters, air temperature and nozzle speed, are studied and their influence on the electrode’s physical properties is examined by different mechanical and electrical analyzes. It was found that elasticity, electrical volume resistivity and adhesion strength of the coating to the substrate, can be dependent on process parameters used for manufacturing. These properties are also influenced by the electrode’s mass loading and its recipe, as the total solvent content and therefore the drying time plays an important role. Assuming binder demixing during drying allows explaining the results, since evaporating solvent induces a temperature dependent compensational flow of solvent and solved binder. If immobilization occurs faster than compensational flow can cause significant demixing, no binder gradient emerges. The driving force counteracts the drying time, but increases demixing, so that optimum drying conditions exist for each mass loading and solid content.
Corrosion Inhibition of C38 Steel in 1M HCl Media by Alkaloidic Extract from Xylopia Frutescens Amazonian Tree
Authors: Chevalier Maxime , Roos Christophe , Tomi Felix , Sutour Sylvain , Lebrini Mounim
Published: May 2015

The use of Xylopia frutescens extract as a C38 steel corrosion inhibitor in 1 M HCl solution was investigated by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) methods. Potentiodynamic polarization curves indicated that Xylopia frutescens extract behaves as mixed-type inhibitor. Graphical methods are illustrated by synthetic data to determine the parameter of CPE (α, Q). The adsorption of the extract constituents was further discussed in view of Langmuir adsorption isotherm. The effect of temperature on the inhibition efficiency was investigated using EIS and potentiodynamic polarization. SEM and EDX observations confirmed the existence of protective inhibitor film on metal surface.
Investigating the Role of Electrolyte Composition and Oxide Structure in Galvanic Corrosion Susceptibility under Atmospheric Electrolytes
Authors: Hangarter Carlos M , Policastro Steven , Martin Farrel J
Published: May 2015

A mechanistic understanding of how electrolyte composition and metal oxide can influence corrosion kinetics in the electrolytes formed from atmospheric processes is investigated. Galvanic couples between aluminum alloys and titanium or stainless steel fasteners exposed to electrolytes formed from atmospheric processes lead to very different corrosion rates. The differences in cathodic current capacity for materials exposed to the same electrolyte at the same aeration level reinforces the fact that oxide microstructure plays a role in catalyzing reduction reactions, though the kinetics of the reaction rates may not be predicted from a simple galvanic series. Also of interest are the changes in reaction rates from acidification of the electrolyte. This suggests that the electrolyte is changing the oxide microstructure or that new reduction reactions are supported and that material loss rates can be orders of magnitude higher for acidified atmospheric electrolytes.
Controllable Fabrication of Nanostructured Sn-TiO2 Composite Films on Cu Sheets as Anode Materials for Lithium-Ion Battery
Authors: Kure-Chu Song-Zhu , Satoh Ayu , Miura Satoshi , Mizuhashi Mitsuru , Yashiro Hitoshi
Published: May 2015

Nanoporous Sn-TiO2 composite films with large surface areas were fabricated on Cu sheets by a hybrid electroplating method, i.e., electrodeposition and electrophoretic deposition, using an ethanol-water mixed bath containing SnCl2 and TiCl3. The Sn-TiO2 composite films, containing a large amount of oxygen and a small amount of TiO2 in 1–4 at%, composed of nano-crystals in forms of dendrites, needles, flakes or scales, which depended predominantly on the mole ratio of [Sn2+]/[Ti3+], the volume ratio of ethanol/water in plating baths, and the current density. The initial specific discharge capacities were 495, 1069, and 772 mAh g-1 for the nanoporous Sn-TiO2 composite films formed in plating baths with EtOH/H2O ratios of 9:1, 6:1, and 3:1, respectively. The enhanced discharge capacity and improved retention of composite films can be attributed to the nanoporous structure and the inclusion of TiO2, which mitigate the volume change during the lithiation and delithiation of Sn nanocrystals.
Influence of Deposition Parameters on Mechanical Stress and Magnetic Properties in Thick, Electroplated Co-Fe Flux Guides
Authors: Kruppe Rahel Maria , Rissing Lutz
Published: May 2015

A notable advantage of electroplated binary Co-Fe alloys in MEMS applications like sensors and actuators is the high saturation flux density BS, which may reach values of 2.4 T in a composition range of 50 – 70 wt% Fe. In contrast, there are certain disadvantages limiting the use of these alloys, e. g. high film stress, high corrosion sensitivity and high magnetostriction. The mechanical and magnetic properties of Co-Fe films influence each other strongly. They are determined by the films’ microstructure, given by film texture, grain size and morphology, structural defects and impurities. In this study, the effect of process conditions like current density, pulse duration, duty cycle, pH-value of the plating bath and application of a constant magnetic field parallel to the electrode surface on film stress, microstructure and magnetic properties are examined.
Electrochemical Studies of 9,10-Anthraquinone in Adiponitrile
Authors: Cheek Graham T.
Published: May 2015

The electrochemical reduction of 9,10-anthraquinone (AQ) has been found to occur in two reversible one-electron processes in the adiponitrile (ADN)/0.20 M TEA BF4 solvent system. Upon addition of aluminum(III) trifluoromethanesulfonate to the solution, the initial reduction process is shifted to a more positive potential due to complexation of the carbonyl oxygen by Al3+. As AQ is reduced, the Al3+ is also able to react with the AQ reduction products. Even at the 0.40 Al3+:1.00 AQ point, the initial reversible processes are entirely absent, implying that Al3+ is able to interact with, or complex, approximately three 9,10-anthraquinone dianion reduction products. This high degree of interaction is also reflected in the large 1.0 V separation between the potentials for reduction of the AQ(AlCl3) complex and the oxidation of the complexed AQ dianions.
Electrochemical Desulfurization of Dibenzothiophene Sulfone in Acetonitrile/Sodium Nitrate (aq)
Authors: González-Perea Mario , Dávila-Jiménez M. M. , Elizalde-González Ma. de la Paz , Ruíz-Gutiérrez P
Published: May 2015

Electrochemical techniques have attracted much attention in the last decade for oxidative and reductive desulfurization because they require less drastic conditions of temperature and pressure in comparison to other processes that are used for desulfurization. It is known that dibenzothiophene (DBT) can be oxidized progressively to dibenzothiophene sulfoxide (DBTO) and dibenzothiophene sulfone (DBTO2). However, it is interesting to know whether a more complete oxidation of DBTO2 is possible by electrochemical treatment in a liquid-liquid two-phase system.
Characterization and Electrochemical Determination of Diclofenac in the Presence of CTAB
Authors: Cid-Cerón Mireya Marlenne , Guzmán-Hernández Dafne Sarahia , Ramirez-Silva Maria Teresa , Rojas-Hernández Alberto , Palomar-Pardavé Manuel , Romero-Romo Mario A.
Published: May 2015

An electrochemical study is presented of the nonsteroidal anti inflammatory drug called Diclofenac at pH 1 and 7, where the protonated and anionic species predominated respectively. It was found that in the presence of CTAB an adsorption process was carried out for both the protonated and the anionic species, respectively. Also, the critical micelle concentration for the system was determined in an aqueous medium. The analytic parameters like the detection and quantification limits in aqueous medium, and the sensitivity for this molecule were determined.
Copper Electroless Process Optimization to Modify Boron Doped Diamond at Different Boron Levels
Authors: Pereira Carlos Felipe , Couto Andrea Boldarini , Baldan Mauricio Ribeiro , Ferreira Neidenei Gomes
Published: May 2015

The copper electroless deposition on semiconducting boron doped diamond (BDD) grown on Ti substrate was investigated. This study emphasizes the influence of the doping level on BDD in the Cu electroless process. In addition, the effect of some deposition parameters such as the pH solution and the deposition time, to obtain Cu/BDD composites were analyzed. Two kinds of BDD films were produced and named as lightly (E1) and highly (E2) BDD electrodes. For both Cu/BDD composites, the scanning electron microscopy showed the deposit morphologies composed by small grains distributed throughout the BDD surface when the electroless process was conducted at pH 12. On the other hand, no Cu deposit was verified at pH 8 and pH 10 for deposition times up to 180 s. However, in these conditions, low particle density was observed for deposition time of 2400 s. In general, the Cu deposit rate increased with increasing the deposition time, for both BDD films. The influence of doping level showed that for E2 electrode, the deposits presented higher density and better uniformity of Cu particle on its surface than those for E1 electrode. This behavior may be associated to the better conductivity of the E2 electrode due to its higher boron content enhancing the Cu deposition. According the X-ray diffraction data, the Cu metallic crystallographic form was obtained for all deposited particles.
Oxygen Electrocatalysis on High-Surface Area Non-Pt Metal Modified Carbon Catalysts
Authors: Härk Eneli , Jäger Rutha , Kasatkin Piia Ereth , Steinberg Vahur , Romann Thomas , Möller P , Kanarbik R , Aruväli J , Kirsimäe K , Lust Enn
Published: May 2015

Series of carbon supported non-noble d-metal Fe or d-metal-nitrogen (Fe-N- or Co-N-) nanocluster activated electrocatalysts have been synthesized by sodium borohydride reduction method. Synthesized d-metal-nitrogen carbon catalysts were studied using X-ray diffraction, scanning electron microscopy, time of flight secondary ion mass-spectrometry and Raman spectroscopy methods. The electrochemical parameters of synthesized catalysts were investigated in alkaline media using cyclic voltammetry and rotating disk electrode methods. The high catalytic activity toward oxygen electroreduction reaction was demonstrated and found to be increasing in the following order: Fe-Vulcan; Co-N-Vulcan; Co-N-C(Mo2C); Fe-N-C(Mo2C). The possibility to replace the Pt metal catalyst with non-noble metal–nitrogen carbon electrocatalyst has been discussed.
Graphitic Carbon Nitride Materials for Energy Applications
Authors: Jorge Sobrido Ana Belen , Dedigama I , Mansor Noramalina , Jervis Rhodri , Miller T S , Corà Furio , Shearing P , Gibbs Christopher , McMillan Paul F. , Brett Dan J.
Published: May 2015

Polymeric layered carbon nitrides were investigated for use as catalyst support materials for proton exchange membrane fuel cells (PEMFCs) and water electrolyzers (PEMWEs). Three different carbon nitride materials were prepared: a heptazine-based graphitic carbon nitride material (gCNM), poly (triazine) imide carbon nitride intercalated with LiCl component (PTI-Li+Cl-) and boron-doped graphitic carbon nitride (B-gCNM). Following accelerated corrosion testing, all graphitic carbon nitride materials were found to be more electrochemically stable compared to conventional carbon black (Vulcan XC-72R) with B-gCNM support showing the best stability. For the supported Pt, Pt/PTI-Li+Cl- exhibited the best durability with only 19% electrochemical surface area (ECSA) loss versus 36% for Pt/Vulcan. Superior methanol oxidation activity was observed for all gCNM supported Pt catalysts on the basis of the catalyst ECSA. Preliminary results on IrO2 supported on gCNM using a PEMWE cell revealed an enhancement in the charge-transfer resistance as the current density increases when compared to unsupported IrO2. This may be attributed to a higher active surface area of the catalyst nanoparticles on the gCNM support.
Mass Transfer in an Anode-Supported Honeycomb Solid Oxide Fuel Cell
Authors: Kotake Shota , Nakajima Hironori , Kitahara Tatsumi
Published: May 2015

An anode-supported honeycomb SOFC can achieve high volumetric power density and improve thermo-mechanical durability at high temperatures. We have so far fabricated the honeycomb cell with a cathode layer made of La0.7Sr0.3MnO3 (LSM) and an electrolyte layer of 8YSZ on a porous anode substrate in honeycomb form of Ni/8YSZ. In the present study, current-voltage characteristics of the cells having different porous substrate thicknesses and anode/cathode flow channel configurations are studied under different flow rates of fed hydrogen to clarify the effect of 3-dimensional fuel transport in the anode porous substrate on the cell performance. We also estimate the hydrogen mole fraction distributions in the honeycomb cell with different anode substrate thicknesses using the finite element method, and discuss appropriate porous anode substrate thickness.