bluuebunny/crossref_metadata_2025 huggingface dataset:
The mysterious cognitive abilities of bees: why models of visual processing need to consider experience and individual differences in animal performance
Authors: Dyer Adrian G.
Published: January 2012

Vision is one of the most important modalities for the remote perception of biologically important stimuli. Insects like honeybees and bumblebees use their colour and spatial vision to solve tasks, such as navigation, or to recognise rewarding flowers during foraging. Bee vision is one of the most intensively studied animal visual systems, and several models have been developed to describe its function. These models have largely assumed that bee vision is determined by mechanistic hard-wired circuits, with little or no consideration for behavioural plasticity or cognitive factors. However, recent work on both bee colour vision and spatial vision suggests that cognitive factors are indeed a very significant factor in determining what a bee sees. Individual bumblebees trade-off speed for accuracy, and will decide on which criteria to prioritise depending upon contextual information. With continued visual experience, honeybees can learn to use non-elemental processing, including configural mechanisms and rule learning, and can access top-down information to enhance learning of sophisticated, novel visual tasks. Honeybees can learn delayed-matching-to-sample tasks and the rules governing this decision making, and even transfer learned rules between different sensory modalities. Finally, bees can learn complex categorisation tasks and display numerical processing abilities for numbers up to and including four. Taken together, this evidence suggests that bees do have a capacity for sophisticated visual behaviours that fit a definition for cognition, and thus simple elemental models of bee vision need to take account of how a variety of factors may influence the type of results one may gain from animal behaviour experiments.
Long-term memory and response generalization in mushroom body extrinsic neurons in the honeybee Apis mellifera
Authors: Haehnel Melanie , Menzel Randolf
Published: January 2012

Honeybees learn to associate an odor with sucrose reward under conditions that allow the monitoring of neural activity by imaging Ca2+ transients in morphologically identified neurons. Here we report such recordings from mushroom body extrinsic neurons – which belong to a recurrent tract connecting the output of the mushroom body with its input, potentially providing inhibitory feedback – and other extrinsic neurons. The neurons' responses to the learned odor and two novel control odors were measured 24 h after learning. We found that calcium responses to the learned odor and an odor that was strongly generalized with it were enhanced compared with responses to a weakly generalized control. Thus, the physiological responses measured in these extrinsic neurons accurately reflect what is observed in behavior. We conclude that the recorded recurrent neurons feed information back to the mushroom body about the features of learned odor stimuli. Other extrinsic neurons may signal information about learned odors to different brain regions.
Independence of net water flux from paracellular permeability in the intestine ofFundulus heteroclitus, a euryhaline teleost
Authors: Wood Chris M. , Grosell Martin
Published: January 2012

Paracellular permeability and absorptive water flux across the intestine of the euryhaline killifish were investigated using in vitro gut sac preparations from seawater- and freshwater-acclimated animals. The permeability of polyethylene glycol (PEG), a well-established paracellular probe, was measured using trace amounts of radiolabelled oligomers of three different molecular sizes (PEG-400, PEG-900 and PEG-4000) at various times after satiation feeding. All three PEG molecules were absorbed, with permeability declining as a linear function of increasing hydrodynamic radius. Response patterns were similar in seawater and freshwater preparations, though water absorption and PEG-900 permeability were greater in the latter. Despite up to 4-fold variations in absorptive water flux associated with feeding and fasting (highest at 1–3 h, lowest at 12–24 h and intermediate at 1–2 weeks post-feeding), there were no changes in PEG permeability for any size oligomer. When PEG permeability was measured in the opposite direction (i.e. serosal to mucosal) from net water flux, it was again unchanged. HgCl2 (10–3 mol l–1), a putative blocker of aquaporins, eliminated absorptive water flux yet increased PEG-4000 permeability by 6- to 8-fold in both freshwater and seawater preparations. Experimentally raising the serosal osmolality by addition of 300 mmol l–1 mannitol increased the absorptive water flux rate 10-fold, but did not alter PEG permeability. Under these conditions, HgCl2 reduced absorptive water flux by 60% and again increased PEG permeability by 6- to 8-fold in both freshwater and seawater preparations. Clearly, there was no influence of solvent drag on PEG movement. The putative paracellular blocker 2,4,6-triaminopyrimidine (TAP, 20 mmol l–1) had no effect on net water flux or PEG permeability. We conclude that PEG and water move by separate pathways; absorptive water transport probably occurs via a transcellular route in the intestine of Fundulus heteroclitus.
Wake structures behind a swimming robotic lamprey with a passively flexible tail
Authors: Leftwich Megan C. , Tytell Eric D. , Cohen Avis H. , Smits Alexander J.
Published: January 2012

A robotic lamprey, based on the silver lamprey, Ichthyomyzon unicuspis, was used to investigate the influence of passive tail flexibility on the wake structure and thrust production during anguilliform swimming. A programmable microcomputer actuated 11 servomotors that produce a traveling wave along the length of the lamprey body. The waveform was based on kinematic studies of living lamprey, and the shape of the tail was taken from a computer tomography scan of the silver lamprey. The tail was constructed of flexible PVC gel, and nylon inserts were used to change its degree of flexibility. Particle image velocimetry measurements using three different levels of passive flexibility show that the large-scale structure of the wake is dominated by the formation of two pairs of vortices per shedding cycle, as seen in the case of a tail that flexed actively according to a pre-defined kinematic pattern, and did not bend in response to fluid forces. When the tail is passively flexible, however, the large structures are composed of a number of smaller vortices, and the wake loses coherence as the degree of flexibility increases. Momentum balance calculations indicate that, at a given tailbeat frequency, increasing the tail flexibility yields less net force, but changing the cycle frequency to match the resonant frequency of the tail increases the force production.
Kinematics of quadrupedal locomotion in sugar gliders (Petaurus breviceps): effects of age and substrate size
Authors: Shapiro Liza J. , Young Jesse W.
Published: January 2012

Arboreal mammals face unique challenges to locomotor stability. This is particularly true with respect to juveniles, who must navigate substrates similar to those traversed by adults, despite a reduced body size and neuromuscular immaturity. Kinematic differences exhibited by juveniles and adults on a given arboreal substrate could therefore be due to differences in body size relative to substrate size, to differences in neuromuscular development, or to both. We tested the effects of relative body size and age on quadrupedal kinematics in a small arboreal marsupial (the sugar glider, Petaurus breviceps; body mass range of our sample 33-97 g). Juvenile and adult P. breviceps were filmed moving across a flat board and three poles 2.5, 1.0 and 0.5 cm in diameter. Sugar gliders (regardless of age or relative speed) responded to relative decreases in substrate diameter with kinematic adjustments that promote stability; they increased duty factor, increased the average number of supporting limbs during a stride, increased relative stride length and decreased relative stride frequency. Limb phase increased when moving from the flat board to the poles, but not among poles. Compared with adults, juveniles (regardless of relative body size or speed) used lower limb phases, more pronounced limb flexion, and enhanced stability with higher duty factors and a higher average number of supporting limbs during a stride. We conclude that although substrate variation in an arboreal environment presents similar challenges to all individuals, regardless of age or absolute body size, neuromuscular immaturity confers unique problems to growing animals, requiring kinematic compensation.
Brain activation pattern depends on the strategy chosen by zebra finches to solve an orientation task
Authors: Mayer Uwe , Bischof Hans-Joachim
Published: January 2012

Zebra finches (Taeniopygia guttata) were trained to find food in one of four feeders on the floor of an aviary. This feeder was always in the same place during training and was additionally marked by a distinct pattern. In the test trial the distinctly patterned feeder was interchanged with one of the other feeders, so that the birds had to decide to use either the pattern or the original location for finding food. Half of the birds used one strategy and half used the other. According to the strategy applied, different brain areas were activated, as demonstrated by c-Fos immunohistochemistry. The hippocampus was activated when spatial cues were used, while in birds orienting using the pattern of the feeder, part of the collothalamic (tectofugal) visual system showed stronger activation. The visual wulst of the lemnothalamic (thalamofugal) visual system was activated with both strategies, indicating an involvement in both spatial and pattern-directed orientation. Because the experimental situation was the same for all zebra finches, the activation pattern was only dependent on the strategy that was voluntarily chosen by each of the birds.
Glycogen synthase kinase-3: cryoprotection and glycogen metabolism in the freeze-tolerant wood frog
Authors: Dieni Christopher A. , Bouffard Melanie C. , Storey Kenneth B.
Published: January 2012

The terrestrial anuran Rana sylvatica tolerates extended periods of whole-body freezing during the winter. Freezing survival is facilitated by extensive glycogen hydrolysis and distribution of high concentrations of the cryoprotectant glucose into blood and all tissues. As glycogenesis is both an energy-expensive process and counter-productive to maintaining sustained high cryoprotectant levels, we proposed that glycogen synthase kinase-3 (GSK-3) would be activated when wood frogs froze and would phosphorylate its downstream substrates to inactivate glycogen synthesis. Western blot analysis determined that the amount of phosphorylated (inactive) GSK-3 decreased in all five tissues tested in 24 h frozen frogs compared with unfrozen controls. Total GSK-3 protein levels did not change, with the exception of heart GSK-3, indicating that post-translational modification was the primary regulatory mechanism for this kinase. Kinetic properties of skeletal muscle GSK-3 from control and frozen frogs displayed differential responses to a temperature change (22 versus 4°C) and high glucose. For example, when assayed at 4°C, the Km for the GSK-3 substrate peptide was ∼44% lower for frozen frogs than the corresponding value in control frogs, indicating greater GSK-3 affinity for its substrates in the frozen state. This indicates that at temperatures similar to the environment encountered by frogs, GSK-3 in frozen frogs will phosphorylate its downstream targets more readily than in unfrozen controls. GSK-3 from skeletal muscle of control frogs was also allosterically regulated. AMP and phosphoenolpyruvate activated GSK-3 whereas inhibitors included glucose, glucose 6-phosphate, pyruvate, ATP, glutamate, glutamine, glycerol, NH4Cl, NaCl and KCl. The combination of phosphorylation and allosteric control argues for a regulatory role of GSK-3 in inactivating glycogenesis to preserve high glucose cryoprotectant levels throughout each freezing bout.
First evidence of epithelial transport in tardigrades: a comparative investigation of organic anion transport
Authors: Halberg Kenneth Agerlin , Møbjerg Nadja
Published: January 2012

We investigated transport of the organic anion Chlorophenol Red (CPR) in the tardigrade Halobiotus crispae using a new method for quantifying non-fluorescent dyes. We compared the results acquired from the tardigrade with CPR transport data obtained from Malpighian tubules of the desert locust Schistocerca gregaria. CPR accumulated in the midgut lumen of H. crispae, indicating that organic anion transport takes place here. Our results show that CPR transport is inhibited by the mitochondrial un-coupler DNP (1 mmol l–1; 81% reduction), the Na+/K+-ATPase inhibitor ouabain (10 mmol l–1; 21% reduction) and the vacuolar H+-ATPase inhibitor bafilomycin (5 μmol l–1; 21% reduction), and by the organic anions PAH (10 mmol l–1; 44% reduction) and probenecid (10 mmol l–1; 61% reduction, concentration-dependent inhibition). Transport by locust Malpighian tubules exhibits a similar pharmacological profile, albeit with markedly higher concentrations of CPR being reached in S. gregaria. Immunolocalization of the Na+/K+-ATPase α-subunit in S. gregaria revealed that this transporter is abundantly expressed and localized to the basal cell membranes. Immunolocalization data could not be obtained from H. crispae. Our results indicate that organic anion secretion by the tardigrade midgut is transporter mediated with likely candidates for the basolateral entry step being members of the Oat and/or Oatp transporter families. From our results, we cautiously suggest that apical H+ and possibly basal Na+/K+ pumps provide the driving force for the transport; the exact coupling between electrochemical gradients generated by the pumps and transport of ions, as well as the nature of the apical exit step, are unknown. This study is, to our knowledge, the first to show active epithelial transport in tardigrades.
Known and novel post-transcriptional regulatory sequences are conserved across plant families
Authors: Vaughn Justin N. , Ellingson Sally R. , Mignone Flavio , von Arnim Albrecht
Published: January 2012

The sequence elements that mediate post-transcriptional gene regulation often reside in the 5′ and 3′ untranslated regions (UTRs) of mRNAs. Using six different families of dicotyledonous plants, we developed a comparative transcriptomics pipeline for the identification and annotation of deeply conserved regulatory sequences in the 5′ and 3′ UTRs. Our approach was robust to confounding effects of poor UTR alignability and rampant paralogy in plants. In the 3′ UTR, motifs resembling PUMILIO-binding sites form a prominent group of conserved motifs. Additionally, Expansins, one of the few plant mRNA families known to be localized to specific subcellular sites, possess a core conserved RCCCGC motif. In the 5′ UTR, one major subset of motifs consists of purine-rich repeats. A distinct and substantial fraction possesses upstream AUG start codons. Half of the AUG containing motifs reveal hidden protein-coding potential in the 5′ UTR, while the other half point to a peptide-independent function related to translation. Among the former, we added four novel peptides to the small catalog of conserved-peptide uORFs. Among the latter, our case studies document patterns of uORF evolution that include gain and loss of uORFs, switches in uORF reading frame, and switches in uORF length and position. In summary, nearly three hundred post-transcriptional elements show evidence of purifying selection across the eudicot branch of flowering plants, indicating a regulatory function spanning at least 70 million years. Some of these sequences have experimental precedent, but many are novel and encourage further exploration.
Instrumental instruction in community bands from Bahia, Brazil
Authors: Barbosa Joel Luis
Published: January 2012

Community bands play an important role in Brazilian music education. Often the only point of musical access, they provide free instrumental teaching for thousands of people who cannot afford to pay. One challenge that needs to be continually addressed is the issue of attrition, especially
during the first stages of instruction. Considering this issue, this paper presents a pedagogical approach which concentrates on music-making through collective instruction. In conclusion, it is suggested that this approach is an effective way to teach instruments, motivate beginners, and
lower the cost of instrumental teaching, making quality instruction available to more people.
Community music as a part of higher education: Decisions from a department chair/researcher
Authors: Rohwer Debbie
Published: January 2012

The following article addresses the partners in the lifelong music cycle (school music, collegiate music and community music) and how these partners might approach music education for the benefit of music participants. While community groups have commonly tapped graduating students
from public schools to feed their groups, there is a need for universities to take part in this cycle by taking ownership of community music as a part of their college music programmes. Considerations are presented concerning the structure and specific content of the curricular topics that
may be needed in the preparation of future instructors and musicians in community music settings.
Community music knowledge exchange research in Scottish higher education
Authors: Moran Nikki , Loening Gica
Published: January 2012

This article examines the usefulness of Knowledge Exchange (KE) funding streams for higher education community music research projects, with a case study of one particular project that took place between February and April 2010. The project was funded via a KE stream, linking University
researchers with a well-established community music charity based in Edinburgh. In order to evaluate the particular value and utility of KE funding streams for community music research, we examine the case study's findings and consider the outcomes desired by the various partners in the project.
Lift every voice and sing: Constructing community through culturally relevant pedagogy in the University of Illinois Black Chorus
Authors: Chadwick Sheelagh
Published: January 2012

For Gloria Ladson-Billings, culturally relevant pedagogy is characterized by three criteria: academic success, cultural competence and critical consciousness. Those engaged in culturally relevant pedagogy are connected by how they see themselves as teachers and how they see their students,
how they view knowledge and how they structure social relations in their classroom. These threads are all evident in the University of Illinois' Black Chorus practice. This article shows how conductor Dr Ollie Watts Davis' culturally relevant practices with the choir generate and sustain a
unique community with strong social bonds that in turn create and reinforce musical excellence, inspiring the singers to do better, live better and sing better while embracing their African American cultural heritage and identity.
Community music and higher education: A marriage of convenience
Authors: Cole Bruce
Published: January 2012

An increasing number of higher education institutions in the United Kingdom are offering an element of community music in their courses, partly in response to changing needs in student training. However, the ethos of community arts, with roots in political activism and welfare, can
often sit uncomfortably in formal education. The need for multi-skilled practitioners presents a problem in higher education, which tends to foster specialism. Community art has also challenged and widened the traditional definition of excellence, which has implications for assessment, particularly
in the area of practical work in the community, which draws on social, healthcare and communication skills alongside the artistic content. There is a danger of 'short-termism' in community contact, and it is important for institutions to foster sustainable links.
When do Third-Party Product Reviews Affect Firm Value and what can Firms Do? The Case of Media Critics and Professional Movie Reviews
Authors: Chen Yubo , Liu Yong , Zhang Jurui
Published: January 2012

Third-party product reviews (TPRs) have become ubiquitous in many industries. Aided by communication technologies, particularly on the Internet, TPRs are widely available to consumers, managers, and investors. The authors examine whether and how TPRs of new products influence the financial value of firms introducing the products. An event study covering 14 major media and professional reviews of movies released by 21 studios shows that TPRs exert significant impact on stock returns in the direction of their valence. However, the impact comes from the valence of a review that is measured relative to other, previously published reviews and not from the absolute valence of the review itself. The authors further study the dynamics of TPR impact on firm value and find that the impact exists only for prerelease reviews and is the strongest on the product release date, though it disappears when sales information becomes available after product release. These results demonstrate that TPRs play significant roles as the investors update their expectation about new product sales potential. The authors also find that advertising spending increases the positive impact of TPRs on firm value and buffer the negative impact. Therefore, firms could strategically use marketing instruments such as advertising to moderate the impact of TPRs.
Diagnostic endoscopic ultrasonography in the gastrointestinal tract
Authors: Czakó László , Szepes Zoltán , Szepes Attila
Published: January 2012

Endoscopic ultrasonography is a relatively new technology that combines the use of flexible fiberoptic endoscopes with high-resolution ultrasound technology. It proved to be highly accurate and useful in the staging of gastrointestinal malignancies, as well as in characterizing the nature of subepithelial lesions and disorders of the pancreaticobiliary system. In this overview the variety of current evidence based diagnostic options of endoscopic ultrasonography are discussed. Orv. Hetil., 2012, 153, 93–101.
The characterization of Electronic state from Surface to Several Nanometer Region on MgO:Si Thin Film
Authors: Nishitani Mikihiko , Fukada Mutsumu , Morita Yukihiro , Terauchi Masaharu , Kurashiki Tessei , Tsuchiura Hiroki , Yamauchi Yasushi
Published: January 2012

We report the properties of MgO:Si film as a protective cathode material on the electrical discharge, and the electronic state of the outer-most surface on MgO:Si film characterized by helium Meta-stable De-excitation Spectroscopy (MDS) and that of several nanometer region from the surface evaluated by X-ray Photoelectron Spectroscopy (XPS). Both of the spectra are discussed focusing on the dependence upon the amount of Si in the MgO film for understanding discharge phenomena. The analyses of the experimental data imply that the discharge properties are not improved due to surface degradation with the increase of Si in MgO films. However, an in-situ discharge experiment, in which MgO:Si films are not exposed for the atmosphere after its deposition, shows that the introduction of Si up to about 1 atomic% has the potential to enhance the secondary electron emission coefficient.
Nanoporous Gold: A Biomaterial for Microfabricated Drug-Delivery Platforms
Authors: Seker Erkin , Berdichevsky Yevgeny , Staley Kevin J. , Yarmush Martin L.
Published: January 2012

Nanoporous gold (np-Au) is a promising nanostructured material with many desirable properties, including large surface area-to-volume ratio, corrosion resistance, high conductivity, and well-studied thiol-based surface chemistry. While np-Au has been used in a variety of applications, from fuel cells to electrochemical sensors, its interface with biology, where many of its exciting applications lie, is surprisingly non-existent. This paper reports on drug delivery from np-Au thin films for modifying cell proliferation in situ. We expect that establishing np-Au as a biomaterial with drug delivery capabilities will create new opportunities for engineering advanced BioMEMS devices that can monitor and modulate biological processes in both in vitro and in vivo settings.
Time-Resolved Emission Spectroscopy Of Electrically Heated Energetic Ni/Al Laminates
Authors: Morris Christopher J. , Wilkins Paul , May Chadd , Weihs Timothy P
Published: January 2012

The nickel-aluminum (Ni/Al) intermetallic system is useful for a variety of reactive material applications, and reaction characteristics are well studied at the normal self-heating rates of 103–106 K/s. Recent experiments at 1011–1012 K/s have measured the kinetic energy of material ejected from the reaction zone, indicating additional kinetic energy from the reactive system despite high heating rates. In order to better probe reaction phenomena at these time scales, and determine the presence of expected elements and their temperatures, we report on emission spectroscopy of electrically heated, patterned Ni/Al bridge wires, time resolved over 350 ns through the use of a streak camera. Unlike previous studies where emission was dominated by Ar and N from residual gasses in the vacuum test chamber, here we report on experiments with encapsulated laminates allowing better quantification of Al and Ni emission. We were able to identify all major spectral lines from the dominant elements present in the films, and found the multilayered Ni/Al laminates to exhibit a brighter and longer duration emission than either Al or Ni control samples. We also found the measured electrical energy absorption of the Ni/Al laminates to follow that of the Al samples up to 150 ns following the onset of emission, indicating that the exothermic mixing of vapor phase Ni and Al was the most likely source for the higher emission intensity. These results will be important for new, energetically enhanced, high efficiency bridge wire applications, where shock initiation of subsequent energetic reactions may be accomplished with less electrical energy than is currently required.
Influence of Gaseous Environment on Reaction Behavior and Phase Formation in Ti/2B Reactive Multilayer Foils
Authors: Reeves Robert V. , Rodriguez Mark A. , Jones Eric D. , Adams David P.
Published: January 2012

The effects of surrounding gaseous environment on the reaction behaviors and product formation for sputter-deposited Ti/2B reactive multilayers are reported. With the surrounding environment set to different air pressures, from atmospheric conditions to 10-4 Torr, Ti/2B samples were reacted in a self-propagating mode, and the average reaction wave velocities were determined through high-speed imaging. Propagation speeds for 3.0 μm-thick multilayers were in the range of 10.89 to 0.05 m/s depending on bilayer thickness (i.e., reactant layer periodicity) and ambient pressure. X-ray diffraction analysis showed that single-phase TiB2 forms within multilayers that have small bilayer thickness. Multilayers that have a large bilayer thickness developed a mixture of TiB2, TiB and TiO2.
Zinc Oxide and Copper Oxide Nanostructures: Fundamentals and Applications
Authors: Willander Magnus , Nur Omer , Amin Gul , Zainelabdin A. , Zaman S.
Published: January 2012

Copper oxide (CuO) and zinc oxide (ZnO) nanostructures complement each other since CuO is unintentional p-type and ZnO unintentional n-type. Using the low temperature chemical growth approach, the effect on morphology of varying the pH of the grown ZnO nanostructures and CuO micro structures is monitored. For both materials the variation of the pH was found to lead to a large variation on the morphology achieved. The grown ZnO NRs and CuO micro flowers material were used to fabricate devices. We demonstrate results from ZnO nanorods (NRs)/polymer p-n hybrid heterojunctions chemically grown on paper and using a process on paper for light emitting diodes (LEDs) applications as well as some large area light emitting diodes LEDs. The growth of CuO micro flowers indicated good quality material for sensing applications. The grown CuO micro flowers were employed as pH sensors. The results indicated a superior performance as expect due to the catalytic properties of this material.
Intercluster Interaction and Magnetic Interaction between Iron Core and Iron Oxide Shell in Core-Shell Nanoclusters
Authors: Kaur Maninder , Yao Qi , Qiang You
Published: January 2012

The intercluster interactions of iron/iron oxide core shell nanoclusters have been investigated, and their dependence on cluster size (d) has been discussed. A cluster deposition system is used to prepare core-shell nanoclusters with different d, varying from 9 to 14 nm.Transmission Electron Microscopy has been used for physical characterization, and Vibrating Sample Magnetometer for magnetic study. The cluster – cluster interactions have been investigated by field dependent isothermal remanent magnetization (IRM) and dc demagnetization (DCD) measurements at room temperature. Henkel plot shows more negative deviation from non- interacting case for bigger size nanoclusters than smaller size clusters.
A Detailed Study of a Novel Wafer Separation Method for Surface Sensitive MEMS Wafers
Authors: Malachowski K. , Severi S. , Van Hoof R. , Sangameswaran S. , Genda S. , Tabuchi T. , Uchiyama N. , Witvrouw A.
Published: January 2012

Abrasive blade dicing is the most common technique for die separation. In this work an alternative dry and non-abrasive die separation method, which is known as "Stealth dicing", is assessed for surface-sensitive MEMS (Micro Electro Mechanical Systems) wafers. The dicing performance and capability of the system is investigated on 200mm full thickness wafers with and without MEMS structures. The diced wafers are analyzed with respect to the silicon cutting quality, possible particle contamination, the condition of functional structures and their mechanical and electrical functionality. In addition the performance and limitations of two different Stealth Dicing Engine (SDE) types, SDE01 and SDE03, are compared to each other with respect to their performance on MEMS wafer dicing.

From this work design rules and proper dimensions of the scribe line can be determined. Process integration solutions, describing steps before and after the Stealth dicing process, including the contact-less dicing tape application to the wafer back side and the final die separation method by tape stretching, are presented. It was also found that the SDE03 laser with its outstanding performance in terms of process speed and separation quality can bring a breakthrough for applying this technology for MEMS wafers.
Harmonic Excitation of Surface Acoustic Waves on Gallium Nitride Thin Films for Biological and Chemical Sensor Applications
Authors: Justice J. , Rodak L. E. , Lee K. , Hornak L. A. , Korakakis D.
Published: January 2012

Gallium nitride (GaN) is a robust piezoelectric semiconductor with excellent thermal and chemical stability, making it an attractive material for surface acoustic wave (SAW) sensors operating in high temperature and harsh environments. The sensitivity of SAW devices is proportional to the square of the operating frequency. Therefore, high operating frequencies into the GHz regime are desirable for SAW sensors. For GaN, this requires sub-micron interdigital transducers (IDTs) when devices are designed to operate at the fundamental Rayleigh mode frequency. The necessity for sub-micron IDTs can increase fabrication costs and complexity. By designing SAW devices to operate at harmonic frequencies, GHz operation can be realized with relatively large IDTs, resulting in simpler and more cost effective solutions for GaN based SAW sensors. Devices have previously been designed to operate at the 5th and higher harmonics on lithium niobate, but there are no reports of using this technique on GaN in the literature. In this study, GaN thin films have been grown via metal organic vapor phase epitaxy on sapphire substrates. SAW devices designed to operate at the fundamental frequency and higher harmonics have been fabricated and measured. Operating frequencies greater than 2 GHz have been achieved using IDTs with 5 μm fingers. In addition, reduction of electromagnetic feedthrough around the 5th and 7th harmonic is demonstrated through varying ground electrode geometries.
Estimating survival rates with time series of standing age‐structure data
Authors: Udevitz Mark S. , Gogan Peter J. P.
Published: January 2012

It has long been recognized that age‐structure data contain useful information for assessing the status and dynamics of wildlife populations. For example, age‐specific survival rates can be estimated with just a single sample from the age distribution of a stable, stationary population. For a population that is not stable, age‐specific survival rates can be estimated using techniques such as inverse methods that combine time series of age‐structure data with other demographic data. However, estimation of survival rates using these methods typically requires numerical optimization, a relatively long time series of data, and smoothing or other constraints to provide useful estimates. We developed general models for possibly unstable populations that combine time series of age‐structure data with other demographic data to provide explicit maximum likelihood estimators of age‐specific survival rates with as few as two years of data. As an example, we applied these methods to estimate survival rates for female bison (Bison bison) in Yellowstone National Park, USA. This approach provides a simple tool for monitoring survival rates based on age‐structure data.
Microalgae Growth Using High‐Strength Wastewater Followed by Anaerobic Co‐Digestion
Authors: Yuan Xin , Wang Meng , Park Chul , Sahu Ashish K. , Ergas Sarina J.
Published: January 2012

Integration of algal biofuel production to wastewater anaerobic digestion infrastructure has the potential to increase biogas production, decrease high and variable internal nitrogen loads, and improve sludge digestibility and dewaterability. In this research, two species of microalgae, Spirulina platensis and Chlorella sp., were grown on sludge centrate and a centrate and nitrified wastewater effluent mixture. Harvested algae were co‐digested with waste activated sludge (WAS) at varying ratios. High‐growth (6.8 g m−2·d−1), nitrogen (36.5 g m−3·d−1), and phosphorus (6.5 g m−3·d−1) uptake rates were achieved with Chlorella on centrate. No growth was observed with S. platensis under the same conditions; however, both organisms grew well on the centrate and effluent mixture. Co‐digestion of algae with WAS improved volatile solids reduction. Although co‐digestion with S. platensis improved biosolids dewaterability, Chlorella had a slight negative effect on dewaterability compared to WAS alone. The efficiency of energy conversion from photons to biogas generated from Chlorella was estimated at 1.4%.
Microbiological and Performance Evaluation of Sequencing Batch Reactor for Textile Wastewater Treatment
Authors: Ogleni Nurtac , Damar Arifoglu Yasemin , Ileri Recep
Published: January 2012

This study focused on laboratory‐scaled and real‐scaled treatment plant performances and microbiological investigations for the optimum treatment of textile industry wastewater performed with sequencing batch reactor (SBR). As a result of experimental studies of laboratory‐scaled SBR treatment unit, optimum treatment efficiency was taken from 0.5 h filling to 1.5 h. reaction to 1.5 h. settlement to 0.5 h. discharge‐idle periods. Average chemical oxygen demand (COD) removal efficiency of SBR of laboratory‐scaled textile industry was 75%, whereas average turbidity and color removal (coloration number [RES, m−1] 586 nm) efficiencies were 90% and 75%, respectively. Optimum reaction and settlement periods were used in a real‐scaled plant, and plant efficiency was examined for parameters such as COD, phenol, pH, mixed liquor suspended solids (MLSS) and sludge volume index (SVI). In this study, optimum reaction and settlement periods for treatment of textile industry wastewater were determined within a SBR in a laboratory‐scaled plant. These reaction and settlement periods were verified with the measurement of COD, color, and turbidity parameters. Floc structure and protozoa‐metazoa species of activated sludge in a SBR were also determined. Optimum reaction and settlement times were used in a real‐scaled plant, and plant efficiency was examined for COD, Phenol, pH, MLSS, and SVI parameters. The corresponding values were found as appropriate, acceptable, and meaningful because of variance value of statistical analysis. Protozoa and metazoan in the activated sludge in the laboratory‐scaled plant were investigated. Peranema sp., Epistylis sp., Didinium sp., Chilodonella sp., Opercularia sp., Vorticella sp. as protozoa species and Habrotrocha sp., Philodina sp. as metazoa species were determined.
Impacts of Amount of Impregnated Iron in Granular Activated Carbon on Arsenate Adsorption Capacities and Kinetics
Authors: Chang Qigang , Lin Wei , Ying Wei‐Chi
Published: January 2012

Iron‐impregnated granular activated carbons (Fe‐GAC) can remove arsenic effectively from water. In this study, Fe‐GACs with iron content of 1.64 to 28.90% were synthesized using a new multi‐step procedure for the investigation of effects of iron amount on arsenic adsorption capacities and kinetics. Langmuir model satisfactorily fit arsenic adsorption on Fe‐GACs. The maximum arsenic adsorption capacity (qm) increased significantly with iron impregnation and reached 1,867 to 1,912 µg/g with iron content of 9.96 to 13.59%. Further increase of iron content (> 13.59%) caused gradual decrease of qm. It was found that the amount of impregnated iron showed little impact on the affinity for arsenate. Kinetic study showed that the amount of impregnated iron affected the arsenic intraparticle diffusion rate greatly. The pseudo‐second‐order kinetic model fit arsenic adsorption kinetics on Fe‐GACs better than the pseudo‐first‐order model. The arsenic adsorption rate increased with increasing of iron content from 1.64% to 13.59%, and then decreased with more impregnated iron (13.59 to 28.90%).
Combination of nondestructive evaluations for reliable assessment of bridge deck
Authors: Khalim A.R. , Sagar D. , Kumruzzaman M.D. , Hasan A.S.M.Z.
Published: January 2012

Non-destructive evaluation (NDE) has offered unprecedented utilize for bridge management body to monitor structural health. None of these evaluation methods can provide all the damage information (damage category, quantitative assessment) alone which is required for necessary repair activity and condition rating of structure. In most of the cases, the response of one evaluation method implies the presence of a defect among the multiple defects to which the evaluation method is sensitive. This paper is concerned with the combination of different non-destructive testing to find out the type of damage with the most efficient way. The different response (positive or negative) obtained from each combination and how it confirms the defect is shown through the mathematical set operation. Thus, this study would assist field investigator to ascertain the type of defect which subsequently aids to rate structure based on damage type.
Building constructions of stone cladded roofs in contemporary architecture
Authors: Dobszay Gergely
Published: January 2012

Stone roof coverings have existed for hundreds of years now, but their application in contemporary representative architecture is quite different than it was in former times, and accordingly the underlying constructional details are much more complicated. The main role of the roof in today's architecture is to emphasize the abstract building volume and its homogeneity. The design (visual appearance) has priority over constructional considerations, while at the same time requirements for thermal insulation and the watertight buildup of the building envelope are rising. This is a big challenge for the design of the constructional details, since traditional methods do not apply anymore: almost all of the water gets under this exterior cladding where a completely waterproof underlayer is needed. Therefore a new type of constructions is borne. In this article I try to present innovative constructional alternatives for stone cladded roofs and try to define guidelines for their planning. These alternatives were created and refined based on analysis of historical and contemporary examples, the examination of the specific conditions and requirements that affect cladded roofs, their expected performance over their life-span, the difficulties that arise under construction and my work experience. I created seven groups, according to the method for fixing the individual stone elements, since this is the detail that most affects the buildup of the underlying structure. A new approach is needed with these unconventional constructions, with a much more detailed inventory of every little feature of the building in question. But since these features vary violently with the architectural conception the exact constructional solutions are usually unique as well.
Usage of dynamic plans in civil engineering of Serbia
Authors: Zlatanovic Milorad , Matejevic Biljana
Published: January 2012

For a successful realization of a civil engineering project, it is necessary to possess good quality dynamic plans of construction works and of resource involvement. Depending on the type and size of the structure, appropriate type of dynamic plan ought to be used. The plan realization must constantly be observed and updated in order to ensure their full effectiveness. This paper presents the results of a research through a survey of dynamic plan implementation in our civil engineering practice. The results are based on the data processed from the responses to the questions asked in the survey of 45 construction enterprises in Serbia.
Seismic performance assessment based on damage of structures, Part 1: Theory
Authors: Ladjinovic Djordje , Radujkovic Aleksandra , Raseta Andrija
Published: January 2012

The paper presents methodology for safety assessment and design of earthquake resistant structures based on application of damage spectra. The damage spectrum can be used for seismic evaluation of vulnerability of structures with given properties and can provide information of damage potential of the recorded ground motions. Damage spectrum represents a variation of a damage index versus structural period for a single-degree-of-freedom system subjected to an earthquake ground motion. The improved damage index, based on plastic deformation and hysteretic energy dissipation, is applied. It depends on maximal plastic deformation, ductility capacity and function including cumulative damage effects. This function, besides the parameter including influence of deterioration, depends on the history of cyclic deformations and on both cyclic and accumulative ductility.
Application of discrete model in analyzes of built and tested composite bridge construction
Authors: Taric Mirsad , Sadovic Enis
Published: January 2012

Designing problem and theoretical analyses of steel-concrete composite structures are especially emphasized in bridge engineering. Method of modelling composite constructions developed and established by standards had been improved by use of finite element method and modern software. By this paper authors wanted to point out the importance of adequate structure modelling assuming all features of steel-concrete bond, and comparing results of experimental research with results of software calculation based on FEM and calculation based on plane theory approach with certain simplifications. Because of research tests necessities the bridge was loaded with four heavy test vehicles. Results, which are represented graphically and numerically were essence for suggestion of giving advantages to area element discretization of composite section over the other one.
Specific problems of media facade design
Authors: Cikic-Tovarovic Jasna , Sekularac Nenad , Ivanovic-Sekularac Jelena
Published: January 2012

During the last years we have been facing a growing need of involving architects into processes of modern city medialization. Transposing contemporary media logic into architecture must be accompanied by qualitative answers within architectural theory and practice. The field of media facade is interdisciplinary - not only does it involve research within architecture and urbanism, but also within some border areas of technology, urban design, art, culture, media and marketing. Media facade design process involves analyses of some specific design aspects.
Examination of bacteriological status of surface fresh waters using direct and cultivation methods
Authors: Ciric Slavica , Petrovic Olga , Ilic Zoran , Milosevic Bozidar , Spasic Zvonko
Published: January 2012

The number of bacteria in surface waters reflects the current state of waters
and their trophicity, and it is the first parameter that is affected by the
anthropogenic contamination. Traditionally, quantification of bacteria in
waters is performed using the cultivation methods. However, all these methods
detect only cultivable bacteria; the results depend on the incubation
conditions, and the results are obtained after several days. These
deficiencies are solved by using direct methods. This work is the first
bacteriological examination of the reservoir Celije and its tributaries by
using a direct method of quantification. Total of 343 samples of water from
the reservoir and its tributaries were processed. In each sample, the count
of aerobic mesophilic bacteria was determined using cultivation method was
involving involved inoculation of samples on high-nutrient PCA medium and on
low-nutrient R2A medium, and incubation for 7 days at room temperature. The
total number of bacteria was determined by epifluorescence microscopy
technique after filtration of samples previously stained with acridine
orange. Using the cultivation methods, the highest number of bacteria was
recorded in the river of Blatasnica on R2A medium (56,535 CFU/ml), and lowest
in the basin Vodozahvat on PCA medium (1,364 CFU/ml). According to the
results from R2A, water belonged to the class of water of poorer quality
compared to the results from the PCA. The results obtained by the direct
method were correlated with cultivation methods. The significantly highest
number of bacteria was obtained by epifluorescence microscopy, and the lowest
on PCA medium. If the application of direct method for some reason is not
possible, the real results of bacteriological state of surface waters can be
obtained by inoculation of samples on R2A medium with adequate incubation
conditions.